63 results on '"John K. Hald"'
Search Results
2. Benign Sphenoid Wing Meningioma Presenting with an Acute Intracerebral Hemorrhage – A Case Report
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Radek Frič, John K. Hald, and Ellen-Ann Antal
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Neurology. Diseases of the nervous system ,RC346-429 - Published
- 2016
3. Radiotherapy for spinal metastases from breast cancer with emphasis on local disease control and pain response using repeated MRI
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Marta D. Switlyk, Øyvind S. Bruland, Sigmund Skjeldal, John K. Hald, Therese Seierstad, and Olga Zaikova
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Bone metastases ,Breast cancer ,MRI ,Pain response ,Radiotherapy ,Diseases of the musculoskeletal system ,RC925-935 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Aims: To evaluate metastatic lesions within the radiation field using repeated magnetic resonance imaging (MRI) and to compare the imaging findings with pain response following radiotherapy (RT) in patients with spinal metastases (SM) from breast cancer. Material and methods: 32 Patients with SM from breast cancer admitted for fractionated RT were included in this study. MRI examinations of the spine were scored for the extent of bone metastases, epidural disease and the presence and severity of vertebral fractures. Clinical response was defined according to the updated international consensus on palliative RT endpoints. Results: At 2 and 6 months after RT, 38% and 44% of the patients were classified as responders. None of the patients developed motor deficits. Importantly, a decrease in the intraspinal tumor volume after RT was reported in all patients. Only 6% of the patients showed bone metastases progression within the RT field, whereas 60% of the patients showed disease progression outside the RT portals. 5 Patients developed new fractures after RT, and fracture progression was observed in 21 of the 38 lesions (55%). The pain response to RT did not correlate with the presence of vertebral body fracture before RT, fracture progression or other recorded MRI features of metastatic lesions. Conclusion: RT provided excellent local tumor control in patients with SM. Most patients benefit from RT even in cases of progressive vertebral fracture. Pain response was not associated with imaging findings and MRI cannot be used to select patients at risk of not responding to RT.
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- 2014
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4. Risk of early failure of VP shunts implanted for hydrocephalus after craniotomies for brain tumors in adults
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Torstein R. Meling, John K. Hald, and Sayied Abdol Mohieb Hosainey
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VP shunt ,Adult ,medicine.medical_specialty ,Complications ,Survival ,medicine.medical_treatment ,Population ,Neurosurgery ,Brain tumor ,Ventriculoperitoneal Shunt ,medicine ,Humans ,Vp shunt ,education ,Craniotomy ,Retrospective Studies ,education.field_of_study ,Brain Neoplasms ,business.industry ,General Medicine ,medicine.disease ,ddc:616.8 ,Hydrocephalus ,Surgery ,Shunting ,Treatment Outcome ,Neurology (clinical) ,business ,Shunt (electrical) - Abstract
Risks and survival times of ventriculoperitoneal (VP) shunts implanted due to hydrocephalus after craniotomies for brain tumors are largely unknown. The purpose of this study was to determine the overall timing of VP shunting and its failure after craniotomy for brain tumors in adults. The authors also wished to explore risk factors for early VP shunt failure (within 90 days). A population-based consecutive patient cohort of all craniotomies for intracranial tumors leading to VP shunt dependency in adults (> 18 years) from 2004 to 2013 was studied. Patients with pre-existing VP shunts prior to craniotomy were excluded. The survival time of VP shunts, i.e., the shunt longevity, was calculated from the day of shunt insertion post-craniotomy for a brain tumor until the day of shunt revision requiring replacement or removal of the shunt system. Out of 4774 craniotomies, 85 patients became VP shunt-dependent (1.8% of craniotomies). Median time from craniotomy to VP shunting was 1.9 months. Patients with hydrocephalus prior to tumor resection (N = 39) had significantly shorter time to shunt insertion than those without (N = 46) (p
- Published
- 2022
5. The Impact of MRI Features and Observer Confidence on the Treatment Decision-Making for Patients with Untreated Glioma
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Kyrre E. Emblem, Inge Rasmus Groote, Atle Bjørnerud, Otto Rapalino, Marco C. Pinho, Paulina Due-Tønnessen, Masafumi Kanoto, John K. Hald, Andreas Abildgaard, and Donatas Sederevicius
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Adult ,Male ,medicine.medical_specialty ,Cancer therapy ,Radiography ,Clinical Decision-Making ,lcsh:Medicine ,Predictive markers ,Article ,030218 nuclear medicine & medical imaging ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Text mining ,Glioma ,Biopsy ,medicine ,Humans ,Sampling (medicine) ,Author Correction ,lcsh:Science ,Pathological ,Aged ,Proportional Hazards Models ,Aged, 80 and over ,Multidisciplinary ,medicine.diagnostic_test ,Brain Neoplasms ,business.industry ,lcsh:R ,Hazard ratio ,Magnetic resonance imaging ,Diagnostic markers ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,3. Good health ,Female ,lcsh:Q ,Cancer imaging ,Radiology ,Neoplasm Grading ,business ,030217 neurology & neurosurgery - Abstract
In a blind, dual-center, multi-observer setting, we here identify the pre-treatment radiologic features by Magnetic Resonance Imaging (MRI) associated with subsequent treatment options in patients with glioma. Study included 220 previously untreated adult patients from two institutions (94 + 126 patients) with a histopathologically confirmed diagnosis of glioma after surgery. Using a blind, cross-institutional and randomized setup, four expert neuroradiologists recorded radiologic features, suggested glioma grade and corresponding confidence. The radiologic features were scored using the Visually AcceSAble Rembrandt Images (VASARI) standard. Results were retrospectively compared to patient treatment outcomes. Our findings show that patients receiving a biopsy or a subtotal resection were more likely to have a tumor with pathological MRI-signal (by T2-weighted Fluid-Attenuated Inversion Recovery) crossing the midline (Hazard Ratio; HR = 1.30 [1.21–1.87], P P P = 0.002) and correlated with the use of a more comprehensive adjuvant treatment protocol (Spearman = 0.48, P
- Published
- 2019
6. The effect of tumor removal via craniotomies on preoperative hydrocephalus in adult patients with intracranial tumors
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Sayied Abdol Mohieb Hosainey, Eirik Helseth, John K. Hald, Benjamin Lassen, and Torstein R. Meling
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,medicine.medical_treatment ,Brain tumor ,Ventriculoperitoneal Shunt ,030218 nuclear medicine & medical imaging ,Young Adult ,03 medical and health sciences ,Postoperative Complications ,0302 clinical medicine ,Risk Factors ,medicine ,Humans ,Vp shunt ,Craniotomy ,Aged ,Retrospective Studies ,Aged, 80 and over ,Adult patients ,Brain Neoplasms ,business.industry ,Incidence ,Incidence (epidemiology) ,General Medicine ,Middle Aged ,medicine.disease ,Surgery ,Hydrocephalus ,Treatment Outcome ,Female ,Neurology (clinical) ,Tumor removal ,Neurosurgery ,business ,030217 neurology & neurosurgery - Abstract
The efficacy of tumor removal via craniotomies on preoperative hydrocephalus (HC) in adult patients with intracranial tumors is largely unknown. Therefore, we sought to evaluate the effect of tumor resection in patients with preoperative HC and identify the incidence and risk factors for postoperative VP shunt dependency. All craniotomies for intracranial tumors at Oslo University Hospital in patients ≥ 18 years old during a 10-year period (2004–2013) were reviewed. Patients with radiologically confirmed HC requiring surgery and subsequent development of shunt dependency were identified by cross-linking our prospectively collected tumor database to surgical procedure codes for hydrocephalus treatment (AAF). Patients with preexisting ventriculoperitoneal (VP) shunts (N = 41) were excluded. From 4774 craniotomies performed on 4204 patients, a total of 373 patients (7.8%) with HC preoperatively were identified. Median age was 54.4 years (range 18.1–83.9 years). None were lost to follow-up. Of these, 10.5% (39/373) required permanent CSF shunting due to persisting postoperative HC. The risk of becoming VP shunt dependent in patients with preexisting HC was 7.0% (26/373) within 30 days and 8.9% (33/373) within 90 days. Only secondary (repeat) surgery was a significant risk factor for VP shunt dependency. In this large, contemporary, single-institution consecutive series, 10.5% of intracranial tumor patients with preoperative HC became shunt-dependent post-craniotomy, yielding a surgical cure rate for HC of 89.5%. To the best of our knowledge, this is the first and largest study regarding postoperative shunt dependency after craniotomies for intracranial tumors, and can serve as benchmark for future studies.
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- 2018
7. Author Correction: The Impact of MRI Features and Observer Confidence on the Treatment Decision-Making for Patients with Untreated Glioma
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Kyrre E. Emblem, Paulina Due-Tønnessen, Otto Rapalino, Marco C. Pinho, Andreas Abildgaard, Atle Bjørnerud, Inge Rasmus Groote, John K. Hald, Masafumi Kanoto, and Donatas Sederevicius
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medicine.medical_specialty ,Multidisciplinary ,Observer (quantum physics) ,business.industry ,Science ,MEDLINE ,medicine.disease ,Glioma ,medicine ,Medicine ,Radiology ,Treatment decision making ,business - Published
- 2021
8. Minimally Invasive Microsurgical Resection of Primary, Intradural Spinal Tumors is Feasible and Safe: A Consecutive Series of 83 Patients
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Charlotte Marie Halvorsen, Iver A. Langmoen, David Scheie, Bjarne Lied, Hege Linnerud Fredø, Daniel Dahlberg, John K. Hald, Eirik Helseth, Maja Formo, and Tor Brommeland
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Adult ,Male ,Ependymoma ,medicine.medical_specialty ,medicine.medical_treatment ,Deep vein ,Neurosurgical Procedures ,Laminoplasty ,Meningioma ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Minimally Invasive Surgical Procedures ,Spinal Cord Neoplasms ,030212 general & internal medicine ,Aged ,Retrospective Studies ,Aged, 80 and over ,Cerebrospinal fluid leak ,business.industry ,Laminectomy ,Middle Aged ,Microsurgery ,medicine.disease ,Surgery ,Pseudomeningocele ,Treatment Outcome ,medicine.anatomical_structure ,Feasibility Studies ,Female ,Neurology (clinical) ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
Background To date, the traditional approach to intraspinal tumors has been open laminectomy or laminoplasty followed by microsurgical tumor resection. Recently, however, minimally invasive approaches have been attempted by some. Objective To investigate the feasibility and safety of minimally invasive surgery (MIS) for primary intradural spinal tumors. Methods Medical charts of 83 consecutive patients treated with MIS for intradural spinal tumors were reviewed. Patients were followed up during the study year, 2015, by either routine history/physical examination or by telephone consultation, with a focus on tumor status and surgery-related complications. Results Mean age at surgery was 53.7 yr and 52% were female. There were 49 schwannomas, 18 meningeomas, 10 ependymomas, 2 hemangioblastomas, 1 neurofibroma, 1 paraganglioma, 1 epidermoid cyst, and 1 hemangiopericytoma. The surgical mortality was 0%. In 87% of cases, gross total resection was achieved. The complication rate was 11%, including 2 cerebrospinal fluid leakages, 1 asymptomatic pseudomeningocele, 2 superficial surgical site infections, 1 sinus vein thrombosis, and 4 cases of neurological deterioration. There were no postoperative hematomas, and no cases of deep vein thrombosis or pulmonary embolism. Ninety-three percent of patients were ambulatory and able to work at the time of follow-up. Conclusion This study both demonstrates that it is feasible and safe to remove select, primary intradural spinal tumors using MIS, and augments the previous literature in favor of MIS for these tumors.
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- 2017
9. Risk factors for new-onset shunt-dependency after craniotomies for intracranial tumors in adult patients
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Torstein R. Meling, Benjamin Lassen, Sayied Abdol Mohieb Hosainey, Eirik Helseth, and John K. Hald
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Adult ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Brain tumor ,Brain Neoplasms/surgery ,Ventriculoperitoneal Shunt ,New onset ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Risk Factors ,medicine ,Humans ,Craniotomy/adverse effects ,Craniotomy ,Aged ,Aged, 80 and over ,Hydrocephalus/etiology/surgery ,Adult patients ,Brain Neoplasms ,business.industry ,General Medicine ,Middle Aged ,medicine.disease ,ddc:616.8 ,Hydrocephalus ,Surgery ,Radiation therapy ,030220 oncology & carcinogenesis ,Female ,Choroid plexus ,Neurology (clinical) ,Neurosurgery ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
The risk of developing a de novo shunt-dependent hydrocephalus (HC) after undergoing a craniotomy for brain tumor in adult patients is largely unknown. All craniotomies for intracranial tumors at Oslo University Hospital in adult patients ≥18 years of age during a 10-year period (2004-2013) were included. None were lost to follow-up. Patients who developed a shunt-dependent HC were identified by cross-linking our prospectively collected tumor database to patients with a NCSP surgical procedure code of hydrocephalus (AAF). Patients with pre-existing HC or ventriculoperitoneal (VP) shunts were excluded from the study. A total of 4401 craniotomies were performed. Of these, 46 patients (1.0%) developed de novo postoperative HC requiring a VP shunt after a median of 93 days (mean 115 days, range 6-442). Median age was 62.0 years (mean 58.9 years, range 27.3-80.9) at time of VP shunt surgery. Patients without pre-existing HC had a 0.2% (n = 8/4401) risk of becoming VP shunt dependent within 30 days and 0.5% (n = 22/4401) within 90 days. Age, sex, tumor location, primary/secondary surgery, and radiotherapy were not associated with VP shunt dependency. Choroid plexus tumors and craniopharyngiomas had increased risk of VP shunt dependency. In this large, contemporary, single-institution consecutive series, the risk of postoperative shunt-dependency after craniotomies for brain tumors without pre-existing HC was very low. This is the largest study with regards to de novo postoperative shunt-dependency after craniotomies for patients with intracranial tumors and can serve as a benchmark for future studies.
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- 2017
10. Seizure outcomes of temporal lobe epilepsy surgery in patients with normal MRI and without specific histopathology
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Kristin Å. Alfstad, Jugoslav Ivanovic, Ylva Østby, J G Fjeld, Arild Egge, Pål G. Larsson, Bård Krossnes, Milo Stanišić, John K. Hald, and Are Hugo Pripp
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Adult ,Male ,0301 basic medicine ,Drug Resistant Epilepsy ,medicine.medical_specialty ,Neurology ,Adolescent ,Prognostic factors ,Temporal lobe ,Young Adult ,03 medical and health sciences ,Epilepsy ,0302 clinical medicine ,Epilepsy surgery ,Outcome Assessment, Health Care ,Normal or non-specific histopathology ,Humans ,Medicine ,Ictal ,Temporal lobe epilepsy ,Neuroradiology ,medicine.diagnostic_test ,business.industry ,Normal MRI ,Magnetic resonance imaging ,Middle Aged ,Postsurgical seizure outcomes ,medicine.disease ,Surgery ,030104 developmental biology ,Epilepsy, Temporal Lobe ,Female ,Neurology (clinical) ,Neurosurgery ,Original Article - Functional ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
Background Seizure outcome following surgery in pharmacoresistant temporal lobe epilepsy patients with normal magnetic resonance imaging and normal or non-specific histopathology is not sufficiently presented in the literature. Methods In a retrospective design, we reviewed data of 263 patients who had undergone temporal lobe epilepsy surgery and identified 26 (9.9%) who met the inclusion criteria. Seizure outcomes were determined at 2-year follow-up. Potential predictors of Engel class I (satisfactory outcome) were identified by logistic regression analyses. Results Engel class I outcome was achieved in 61.5% of patients, 50% being completely seizure free (Engel class IA outcome). The strongest predictors of satisfactory outcome were typical ictal seizure semiology (p = 0.048) and localised ictal discharges on scalp EEG (p = 0.036). Conclusion Surgery might be an effective treatment choice for the majority of these patients, although outcomes are less favourable than in patients with magnetic resonance imaging-defined lesional temporal lobe epilepsy. Typical ictal seizure semiology and localised ictal discharges on scalp EEG were predictors of Engel class I outcome.
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- 2017
11. Benign Sphenoid Wing Meningioma Presenting with an Acute Intracerebral Hemorrhage – A Case Report
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Ellen-Ann Antal, Radek Frič, and John K. Hald
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sphenoid wing ,medicine.medical_specialty ,Case Report ,intracranial meningioma ,Meningothelial Meningioma ,lcsh:RC346-429 ,03 medical and health sciences ,0302 clinical medicine ,Hematoma ,medicine ,lcsh:Neurology. Diseases of the nervous system ,Intracerebral hemorrhage ,Coma ,Sphenoid wing meningioma ,medicine.diagnostic_test ,business.industry ,Cancer ,medicine.disease ,intracerebral hemorrhage ,Angiography ,brain tumors ,030211 gastroenterology & hepatology ,Radiology ,medicine.symptom ,Presentation (obstetrics) ,business ,030217 neurology & neurosurgery ,Biomedical engineering - Abstract
Background and Study Object We report an unusual case of a benign lateral sphenoid wing meningioma that presented with, and was masked by, an acute intracerebral hemorrhage. Case Report A 68-year-old woman was admitted after sudden onset of coma. Computed tomography (CT) revealed an intracerebral hemorrhage, without any underlying vascular pathology on CT angiography. During the surgery, we found a lateral sphenoid wing meningioma with intratumoral bleeding that extended into the surrounding brain parenchyma. Results We removed the hematoma and resected the tumor completely in the same session. The histopathological classification of the tumor was a WHO grade I meningothelial meningioma. The patient recovered very well after surgery, without significant neurological sequelae. Conclusions Having reviewed the relevant references from the medical literature, we consider this event as an extremely rare presentation of a benign sphenoid wing meningioma in a patient without any predisposing medical factors. The possible mechanisms of bleeding from this tumor type are discussed.
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- 2016
12. A Generic Support Vector Machine Model for Preoperative Glioma Survival Associations
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Paulina Due-Tønnessen, Kyrre E. Emblem, Frank G. Zöllner, Otto Rapalino, Atle Bjørnerud, John K. Hald, Torstein R. Meling, Lothar R. Schad, and Marco Da Cunha Pinho
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Adult ,Male ,Oncology ,medicine.medical_specialty ,Support Vector Machine ,Adolescent ,MEDLINE ,Contrast Media ,Magnetic Resonance Imaging/methods ,Computer-Assisted ,Text mining ,Glioma ,Internal medicine ,Image Interpretation, Computer-Assisted ,80 and over ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Radiation treatment planning ,Image Interpretation ,Glioma/mortality/pathology ,Survival analysis ,Aged ,Retrospective Studies ,Aged, 80 and over ,Brain Neoplasms ,business.industry ,Retrospective cohort study ,Middle Aged ,Brain Neoplasms/mortality/pathology ,medicine.disease ,Magnetic Resonance Imaging ,Survival Analysis ,Mr imaging ,ddc:616.8 ,Surgery ,Support vector machine ,Female ,business - Abstract
To develop a generic support vector machine (SVM) model by using magnetic resonance (MR) imaging-based blood volume distribution data for preoperative glioma survival associations and to prospectively evaluate the diagnostic effectiveness of this model in autonomous patient data.Institutional and regional medical ethics committees approved the study, and all patients signed a consent form. Two hundred thirty-five preoperative adult patients from two institutions with a subsequent histologically confirmed diagnosis of glioma after surgery were included retrospectively. An SVM learning technique was applied to MR imaging-based whole-tumor relative cerebral blood volume (rCBV) histograms. SVM models with the highest diagnostic accuracy for 6-month and 1-, 2-, and 3-year survival associations were trained on 101 patients from the first institution. With Cox survival analysis, the diagnostic effectiveness of the SVM models was tested on independent data from 134 patients at the second institution.were adjusted for known survival predictors, including patient age, tumor size, neurologic status, and postsurgery treatment, and were compared with survival associations from an expert reader.Compared with total qualitative assessment by an expert reader, the whole-tumor rCBV-based SVM model was the strongest parameter associated with 6-month and 1-, 2-, and 3-year survival in the independent patient data (area under the receiver operating characteristic curve, 0.794-0.851; hazard ratio, 5.4-21.2).Machine learning by means of SVM in combination with whole-tumor rCBV histogram analysis can be used to identify early patient survival in aggressive gliomas. The SVM model returned higher diagnostic accuracy values than an expert reader, and the model appears to be insensitive to patient, observer, and institutional variations.
- Published
- 2015
13. Imaging spectrum of central nervous system complications of hematopoietic stem cell and solid organ transplantation
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Francesc Graus, John K. Hald, Andres Server, Jon Sponheim, Núria Bargalló, and Yngvar Fløisand
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medicine.medical_specialty ,Neurology ,medicine.medical_treatment ,Hematopoietic stem cell transplantation ,03 medical and health sciences ,0302 clinical medicine ,Postoperative Complications ,Central Nervous System Diseases ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Neuroradiology ,business.industry ,Hematopoietic Stem Cell Transplantation ,Hematopoietic stem cell ,Organ Transplantation ,Surgery ,Transplantation ,surgical procedures, operative ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Etiology ,Neurology (clinical) ,Neurosurgery ,Stem cell ,Cardiology and Cardiovascular Medicine ,business ,030217 neurology & neurosurgery - Abstract
Neurologic complications are common after hematopoietic stem cell transplantation (HSCT) and solid organ transplantation (SOT) and affect 30-60% of transplant recipients. The aim of this article is to provide a practical imaging approach based on the timeline and etiology of CNS abnormalities, and neurologic complications related to transplantation of specific organs. The lesions will be classified based upon the interval from HSCT procedure: pre-engraftment period30 days, early post-engraftment period 30-100 days, late post-engraftment period100 days, and the interval from SOT procedure: postoperative phase 1-4 weeks, early posttransplant syndromes 1-6 months, late posttransplant syndromes6 months. Further differentiation will be based on etiology: infections, drug toxicity, metabolic derangements, cerebrovascular complications, and posttransplantation malignancies. In addition, differentiation will be based on complications specific to the type of transplantation: allogeneic and autologous hematopoietic stem cells (HSC), heart, lung, kidney, pancreas, and liver. Thus, in this article we emphasize the strategic role of neuroradiology in the diagnosis and response to treatment by utilizing a methodical approach in the work up of patients with neurologic complications after transplantation.
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- 2017
14. Estimation of Chronic Subdural Hematoma Size Using CT Imaging; a Comparison of In-Plane Thickness to 3D Volumetry
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Are Hugo Pripp, Inge Rasmuss Groote, Milo Stanišić, and John K. Hald
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medicine.medical_specialty ,business.industry ,Lesion volume ,Common method ,medicine.disease ,Lesion ,In plane ,Hematoma ,Chronic subdural hematoma ,medicine ,Tomography ,Radiology ,medicine.symptom ,Ct imaging ,business - Abstract
Backgrounds: Pre- and postoperative chronic subdural hematoma (CSDH) sizes have been used in clinical trials to predict the risk of postoperative recurrence. Commonly, dimensions of the pre- and postoperative lesions have been assessed by computerized tomography (CT) scans using maximum thickness as a linear measurement. Our goal was to characterize this common method for quantification of pre- and postoperative lesion sizes and to assess its estimation validity compared to estimation by hematoma volumetry. Methods: We prospectively investigated pre- and 1st postoperative day CT scans of 107 adult surgical patients with uni- or bilateral CSDH. Pre- and postoperative thickness of CSDH was determined and then compared to pre- and postoperative lesion volume measured with 3D hematoma volumetry. Results: Pearson correlation coefficients between mean pre- and postoperative lesion thickness and mean pre- and postoperative lesion volume in the unilateral subgroup were 0.491 and 0.498, respectively; in the bilateral subgroup 0.505 and 0.579, respectively; and in the whole series 0.653 and 0.472, respectively. Conclusions: Pre- and postoperative thickness of CSDH does not offer reasonable approximations of the pre- and postoperative lesion size when compared with results from 3D volumetry in the unilateral subgroup, bilateral subgroup or overall.
- Published
- 2014
15. Volume and densities of chronic subdural haematoma obtained from CT imaging as predictors of postoperative recurrence: a prospective study of 107 operated patients
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Mark Züchner, Milo Stanišić, John K. Hald, Inge Rasmussen, Jarle Sundseth, Frode Kolstad, Are Hugo Pripp, Jugoslav Ivanovic, and Karl-Fredrik Lindegaard
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Adult ,Male ,medicine.medical_specialty ,Neurology ,Clinical Neurology ,Risk Assessment ,Chronic subdural haematoma ,Computerised tomography ,Recurrence ,Predictive Value of Tests ,medicine ,Humans ,Prospective Studies ,Prospective cohort study ,Therapeutic Irrigation ,Densities ,Neuroradiology ,Aged ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Volume ,Interventional radiology ,Middle Aged ,Surgery ,Treatment Outcome ,Clinical Article - Brain Injury ,Hematoma, Subdural, Chronic ,Multiple regression ,Drainage ,Regression Analysis ,Female ,Neurology (clinical) ,Neurosurgery ,Radiology ,Tomography ,Ct imaging ,business ,Tomography, X-Ray Computed ,Craniotomy - Abstract
Background Chronic subdural haematoma (CSDH) is a common entity in neurosurgery with a considerable postoperative recurrence rate. Computerised tomography (CT) scanning remains the most important diagnostic test for this disorder. The aim of this study was to characterise the relationship between the recurrence of CSDH after treatment with burr-hole irrigation and closed-system drainage technique and CT scan features of these lesions to assess whether CT findings can be used to predict recurrence. Methods We investigated preoperative and postoperative CT scan features and recurrence rate of 107 consecutive adult surgical cases of CSDH and assessed any relationship with univariate and multivariate regression analyses. Results Seventeen patients (15.9 %) experienced recurrence of CSDH. The preoperative haematoma volume, the isodense, hyperdense, laminar and separated CT densities and the residual total haematoma cavity volume on the 1st postoperative day after removal of the drainage were identified as radiological predictors of recurrence. If the preoperative haematoma volume was under 115 ml and the residual total haematoma cavity volume postoperatively was under 80 ml, the probability of no recurrence was very high (94.4 % and 97.4 % respectively). Conclusions These findings from CT imaging may help to identify patients at risk for postoperative recurrence.
- Published
- 2012
16. Multiparametric analysis of magnetic resonance images for glioma grading and patient survival time prediction
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Paulina Due-Tønnessen, Atle Bjørnerud, Benjamin Garzon, Terje Nome, Kyrre E. Emblem, Asta Håberg, Kim Mouridsen, John K. Hald, Baard Nedregaard, and Yngve Kvinnsland
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Adult ,Male ,Pathology ,medicine.medical_specialty ,Logistic regression ,Glioma ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,neoplasms ,Aged ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,Brain Neoplasms ,business.industry ,Multiparametric Analysis ,Magnetic resonance imaging ,General Medicine ,Middle Aged ,Stepwise regression ,equipment and supplies ,medicine.disease ,Magnetic Resonance Imaging ,Regression ,nervous system diseases ,Glioma grading ,Kurtosis ,Female ,Neoplasm Grading ,business ,Nuclear medicine ,human activities - Abstract
Background A systematic comparison of magnetic resonance imaging (MRI) options for glioma diagnosis is lacking. Purpose To investigate multiple MR-derived image features with respect to diagnostic accuracy in tumor grading and survival prediction in glioma patients. Material and Methods T1 pre- and post-contrast, T2 and dynamic susceptibility contrast scans of 74 glioma patients with histologically confirmed grade were acquired. For each patient, a set of statistical features was obtained from the parametric maps derived from the original images, in a region-of-interest encompassing the tumor volume. A forward stepwise selection procedure was used to find the best combinations of features for grade prediction with a cross-validated logistic model and survival time prediction with a cox proportional-hazards regression. Results Presence/absence of enhancement paired with kurtosis of the FM (first moment of the first-pass curve) was the feature combination that best predicted tumor grade (grade II vs. grade III-IV; median AUC = 0.96), with the main contribution being due to the first of the features. A lower predictive value (median AUC = 0.82) was obtained when grade IV tumors were excluded. Presence/absence of enhancement alone was the best predictor for survival time, and the regression was significant ( P < 0.0001). Conclusion Presence/absence of enhancement, reflecting transendothelial leakage, was the feature with highest predictive value for grade and survival time in glioma patients.
- Published
- 2011
17. CT of the hips in the investigation of protrusio acetabuli in Marfan syndrome. A case control study
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Eva Kirkhus, Svend Rand-Hendriksen, Hans-Jørgen Smith, Rigmor Lundby, John K. Hald, and Are Hugo Pripp
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musculoskeletal diseases ,Marfan syndrome ,Adult ,Male ,congenital, hereditary, and neonatal diseases and abnormalities ,medicine.medical_specialty ,Protrusio acetabuli ,Adult population ,Marfan Syndrome ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,skin and connective tissue diseases ,Hip joint ,Computed tomography (CT) ,Neuroradiology ,Aged ,Pelvic bones ,Connective tissue diseases ,Analysis of Variance ,Chi-Square Distribution ,business.industry ,Case-control study ,Acetabulum ,General Medicine ,Middle Aged ,medicine.disease ,Surgery ,Musculoskeletal Abnormalities ,Tomography x ray computed ,ROC Curve ,Radiology Nuclear Medicine and imaging ,Musculoskeletal ,Case-Control Studies ,Female ,Radiology ,business ,Tomography, X-Ray Computed - Abstract
Objectives To establish the prevalence of protrusio acetabuli (PA) in adults fulfilling the Ghent criteria for Marfan syndrome (MFS), and in a normal adult population. Methods 105 adults with probable MFS and 107 controls were included. CT of the hips was obtained. A qualitative assessment of PA was performed. A new method for estimating the degree of PA was introduced with measurement of the parameter CWD (circle-wall distance). Results were compared to an alternative method based on MRI [1]. Results 87 of the study group fulfilled the Ghent criteria of MFS (Ghent positives), and 18 did not (Ghent negatives). PA was diagnosed qualitatively in 74.7% of Ghent positive persons, in 27.8% of Ghent negative persons, and in 3.7% of the controls. CWD was significantly different between the three groups (p
- Published
- 2011
18. Long-term Outcome After Resection of Intraspinal Ependymomas: Report of 86 Consecutive Cases
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Bård Krossnes, John K. Hald, Bjarne Lied, Signe Spetalen, Frode Kolstad, Iver A. Langmoen, Eirik Helseth, Pål Rønning, Sigrun Skaar, Tom Børge Johannesen, and Charlotte Marie Halvorsen
- Subjects
Adult ,Male ,Ependymoma ,medicine.medical_specialty ,Neoplasm, Residual ,Adolescent ,medicine.medical_treatment ,Neurosurgery ,Physical examination ,Preoperative care ,Disease-Free Survival ,Young Adult ,medicine ,Humans ,Longitudinal Studies ,Progression-free survival ,Radical surgery ,Child ,Survival rate ,Aged ,Retrospective Studies ,Neurologic Examination ,Spinal Neoplasms ,medicine.diagnostic_test ,business.industry ,Retrospective cohort study ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Surgery ,Radiation therapy ,Treatment Outcome ,Female ,Radiotherapy, Adjuvant ,Neurology (clinical) ,business - Abstract
BACKGROUND: Objective: To evaluate progression-free survival, overall survival (OS) and long-term clinical outcome in a consecutive series of 86 patients with intraspinal ependymomas. METHODS: Medical charts were retrospectively reviewed. Surviving patients voluntarily participated in a clinical history and physical examination that focused on neurological function and current tumor status. RESULTS: Follow-up data are nearly 100% complete; mean follow-up time was 82 months. Eighty-five patients (99%) had surgery as a first-line treatment; 14 (17%) of these patients received adjuvant radiotherapy. Of the 85 patients who underwent primary surgery, gross total resection was performed in 60 patients (71 %) and subtotal resection in 25 patients (29%). Ten-year progression-free survival rate was 75%; 5-year OS, 97%; and 10-year OS, 91%. Reduced preoperative neurological function and older age at diagnosis were significantly associated with increased risk of death. At follow-up, spontaneous regression of residual tumor after primary surgery may have occurred in 7 of 19 patients (37%). More than 75% of patients had neurological function compatible with an independent life at follow-up. Good preoperative neurological function was significantly associated with favorable outcome. It was not possible to evaluate the effect of radiotherapy on progression-free survival and OS. CONCLUSION: Gross total resection remains the optimal treatment for patients with spinal ependymoma. Patients should be monitored with a clinical examination and magnetic resonance imaging at regular intervals up to 10 years after surgery.
- Published
- 2010
19. A piglet model for detection of hypoxic-ischemic brain injury with magnetic resonance imaging
- Author
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Berit H. Munkeby, John K. Hald, Grete A.B. Kro, Kyrre E. Emblem, Else Marit Løberg, Atle Bjørnerud, E. H. Winther-Larssen, Jannicke H Andresen, and C. De Lange
- Subjects
In vivo magnetic resonance spectroscopy ,Pathology ,medicine.medical_specialty ,Magnetic Resonance Spectroscopy ,Swine ,Ischemia ,MR diffusion/perfusion ,Creatine ,Basal Ganglia ,Choline ,chemistry.chemical_compound ,Fractional anisotropy ,Animals ,Medicine ,Effective diffusion coefficient ,Radiology, Nuclear Medicine and imaging ,Lactic Acid ,Animal investigations ,Brain Chemistry ,Aspartic Acid ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,business.industry ,brain/brainstem ,MR spectroscopy ,Brain ,Magnetic resonance imaging ,General Medicine ,medicine.disease ,Magnetic Resonance Imaging ,Disease Models, Animal ,Diffusion Magnetic Resonance Imaging ,Animals, Newborn ,chemistry ,Hypoxia-Ischemia, Brain ,Original Article ,CNS ,business ,Nuclear medicine ,Microtubule-Associated Proteins ,Perfusion ,MR imaging ,Diffusion MRI - Abstract
Munkeby BH, de Lange C, Emblem KE, Bjørnerud A, Kro GAB, Andresen J, Winther-Larssen EH, Løberg EM, Hald JK. A piglet model for detection of hypoxic-ischemic brain injury with magnetic resonance imaging. Acta Radiol 2008;49:1049–1057. Background Early detection of hypoxic-ischemic (HI) injury in the asphyxic newborn is important because present prognostic factors are inadequate. Furthermore, therapeutic interventions may have additional benefit if initiated in time. Purpose To assess whether the use of a combined protocol including conventional magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI), and proton MR spectroscopy (MRS) could detect pathological findings in a piglet model 7 hours after HI. Material and Methods Ten piglets were submitted to HI for 30 min followed by reoxygenation with 21% O2 for 7 hours. MRI at 1.5T was done prior to and 7 hours after the HI. Single-voxel proton MRS was performed, and apparent diffusion coefficient (ADC) and fractional anisotropy (FA) were measured in the basal ganglia. MRS identified N-acetylaspartate (NAA), choline (Cho), creatine (Cr), and lactate (Lac). Histology and microtubule-associated protein 2 (MAP-2) staining was performed in the basal ganglia at the end of the experiment. Results Compared to baseline, ADC, NAA/Cho, and NAA/Cr were significantly reduced after 7 hours (P < 0.001, P = 00.01, and P = 00.05, respectively) and FA values were increased (P
- Published
- 2008
20. Glioma Grading by Using Histogram Analysis of Blood Volume Heterogeneity from MR-derived Cerebral Blood Volume Maps
- Author
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David Scheie, Kyrre E. Emblem, Atle Bjørnerud, Milada Cvancarova, Terje Nome, Olivera Casar Borota, Paulina Due-Tønnessen, John K. Hald, and Baard Nedregaard
- Subjects
Adult ,Male ,Pathology ,medicine.medical_specialty ,Adolescent ,Contrast Media ,Diagnostic accuracy ,Blood volume ,Sensitivity and Specificity ,Statistics, Nonparametric ,Predictive Value of Tests ,Glioma ,Histogram ,Image Interpretation, Computer-Assisted ,Organometallic Compounds ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Aged ,Neoplasm Staging ,Retrospective Studies ,Alternative methods ,Blood Volume ,Brain Neoplasms ,business.industry ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,humanities ,body regions ,Logistic Models ,Cerebral blood volume ,Glioma grading ,Cerebrovascular Circulation ,Female ,Neoplasm staging ,Nuclear medicine ,business ,circulatory and respiratory physiology - Abstract
To retrospectively compare the diagnostic accuracy of an alternative method used to grade gliomas that is based on histogram analysis of normalized cerebral blood volume (CBV) values from the entire tumor volume (obtained with the histogram method) with that of the hot-spot method, with histologic analysis as the reference standard.The medical ethics committee approved this study, and all patients provided informed consent. Fifty-three patients (24 female, 29 male; mean age, 48 years; age range, 14-76 years) with histologically confirmed gliomas were examined with dynamic contrast material-enhanced 1.5-T magnetic resonance (MR) imaging. CBV maps were created and normalized to unaffected white matter (normalized CBV maps). Four neuroradiologists independently measured the distribution of whole-tumor normalized CBVs and analyzed this distribution by classifying the values into area-normalized bins. Glioma grading was performed by assessing the normalized peak height of the histogram distributions. Logistic regression analysis and interobserver agreement were used to compare the proposed method with a hot-spot method in which only the maximum normalized CBV was used.For the histogram method, diagnostic accuracy was independent of the observer. Interobserver agreement was almost perfect for the histogram method (kappa = 0.923) and moderate for the hot-spot method (kappa = 0.559). For all observers, sensitivity was higher with the histogram method (90%) than with the hot-spot method (55%-76%).Glioma grading based on histogram analysis of normalized CBV heterogeneity is an alternative to the established hot-spot method, as it offers increased diagnostic accuracy and interobserver agreement.
- Published
- 2008
21. Low Levels of Raf Kinase Inhibitory Protein in Growth Hormone-Secreting Pituitary Adenomas Correlate with Poor Response to Octreotide Treatment
- Author
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Jens Bollerslev, Terje Lund, Jon Ramm-Pettersen, Fahim Latif, Stine Lyngvi Fougner, Jens P. Berg, and John K. Hald
- Subjects
Adenoma ,Adult ,Male ,medicine.medical_specialty ,Antineoplastic Agents, Hormonal ,Somatotropic cell ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Octreotide ,Phosphatidylethanolamine Binding Protein ,Biology ,Biochemistry ,Endocrinology ,Internal medicine ,Acromegaly ,medicine ,Humans ,Somatostatin receptor 2 ,Receptors, Somatostatin ,G protein-coupled receptor ,Somatostatin receptor ,Biochemistry (medical) ,Pituitary tumors ,Middle Aged ,medicine.disease ,Somatostatin ,Female ,Growth Hormone-Secreting Pituitary Adenoma ,medicine.drug - Abstract
Excessive GH production by pituitary tumors causes acromegaly. Medical treatment of acromegaly with somatostatin analogs (SMSs), like octreotide, is well established, but the clinical effect is variable. One mechanism for octreotide effect is inhibition of the MAPK signaling pathway after binding to the G protein-coupled somatostatin receptor. Nonphosphorylated Raf kinase inhibitory protein (RKIP) binds to and inhibits Raf1 kinase, and thereby attenuates MAPK signaling, whereas phosphorylated RKIP inhibits G protein receptor internalization and degradation due to inhibition of G protein receptor kinase 2.Our objective was to study RKIP levels in pituitary somatotroph adenomas, and relate them to clinical characteristics and response to octreotide treatment in patients with acromegaly.RKIP level was analyzed by Western blot of proteins extracted from somatotroph tumors frozen a short time after surgery in 51 patients with active acromegaly. An acute somatostatin test was performed in 46 of the patients, and in 21 the IGF-I level before and 6 months after SMS treatment was available.The adenoma RKIP level correlated significantly to both the acute and the long-term octreotide responses on serum levels of GH and IGF-I, respectively. In multiple regression analyses, the RKIP level was a significant determinant for both the GH reduction in the acute test and the IGF-I reduction after approximately 6 months.The RKIP level in somatotroph adenomas seems to be important for the clinical effect of SMS treatment, in which low levels of RKIP correlate to poor clinical response to SMSs.
- Published
- 2008
22. From intracranial pressure to intracranial pressure wave-guided intensive care management of a patient with an aneurysmal subarachnoid haemorrhage
- Author
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Torstein R. Meling, Per Kristian Eide, Audun Stubhaug, Wilhelm Sorteberg, John K. Hald, and E. Jörum
- Subjects
Time Factors ,Subarachnoid hemorrhage ,Critical Care ,Intracranial Pressure ,Cerebrospinal fluid ,Intensive care ,medicine ,Humans ,cardiovascular diseases ,Aged ,Monitoring, Physiologic ,Intracranial pressure ,Coma ,integumentary system ,medicine.diagnostic_test ,business.industry ,musculoskeletal, neural, and ocular physiology ,Glasgow Coma Scale ,Brain ,Electroencephalography ,Intracranial Aneurysm ,Magnetic resonance imaging ,Recovery of Function ,General Medicine ,Subarachnoid Hemorrhage ,medicine.disease ,Magnetic Resonance Imaging ,humanities ,nervous system diseases ,Treatment Outcome ,Anesthesiology and Pain Medicine ,Anesthesia ,Evoked Potentials, Auditory ,Female ,medicine.symptom ,business ,External ventricular drain - Abstract
We report on a 65-year-old female with an aneurysmal subarachnoid hemorrhage (SAH) that was followed clinically, radiologically and electrophysiologically before and after converting from intracranial pressure (ICP)-guided to ICP wave-guided intensive care management. Intracranial pressure-guided management is aimed at keeping mean ICP < 15-20 mmHg, while ICP wave-guided management is aimed at keeping mean ICP wave amplitude < 5 mmHg. The aims of management were obtained by adjusting cerebrospinal fluid (CSF) draining volume from her external ventricular drain. No improvement was seen clinically or in cerebral magnetic resonance imaging (MRI) scans during the ICP-guided management. Clinical, MRI and neurophysiologic (electroencephalography and auditory evoked responses) improvements were obvious within 2 days after converting from ICP- to ICP wave-guided management. This case report describes how we used various ICP parameters to guide intensive care management of an aneurysmal SAH patient.
- Published
- 2007
23. The Long-term Outcome After Resection of Intraspinal Nerve Sheath Tumors: Report of 131 Consecutive Cases
- Author
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Sigrun Skaar Holme, Tom Børge Johannesen, Iver A. Langmoen, Frode Kolstad, Eirik Helseth, Pål Rønning, Charlotte Marie Halvorsen, Bjarne Lied, and John K. Hald
- Subjects
Adult ,Male ,medicine.medical_specialty ,Time Factors ,Adolescent ,Physical examination ,Malignant peripheral nerve sheath tumor ,Schwannoma ,Disease-Free Survival ,Nerve Sheath Neoplasms ,Young Adult ,medicine ,Neurofibroma ,Humans ,Progression-free survival ,Prospective Studies ,Neurofibromatosis ,Schwannomatosis ,Child ,Aged ,Retrospective Studies ,Aged, 80 and over ,Spinal Neoplasms ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Surgery ,Spinal Nerves ,Treatment Outcome ,Child, Preschool ,Disease Progression ,Female ,Neurology (clinical) ,Neoplasm Recurrence, Local ,business ,Follow-Up Studies - Abstract
BACKGROUND The existing literature on recurrence rates and long-term clinical outcome after resection of intraspinal nerve sheath tumors is limited. OBJECTIVE To evaluate progression-free survival, overall survival, and long-term clinical outcome in a consecutive series of 131 patients with symptomatic intraspinal nerve sheath tumors. METHODS Medical charts were retrospectively reviewed. Surviving patients voluntarily participated in a clinical history and physical examination that focused on neurological function and current tumor status. RESULTS Follow-up data are 100% complete; median follow-up time was 6.1 years. All patients (100%) had surgery as the first line of treatment; gross total resection was performed in 112 patients (85.5%) and subtotal resection in 19 patients (14.5%). Five-year progression-free survival was 89%. The following risk factors for recurrence were identified: neurofibroma, malignant peripheral nerve sheath tumor, subtotal resection, neurofibromatoses/schwannomatosis, and advancing age at diagnosis. More than 95% of patients had neurological function compatible with an independent life at follow-up. The rate of tumor recurrence in nonneurofibromatosis patients undergoing total resection of a single schwannoma was 3% (3/93), in comparison with a recurrence rate of 32% (12/38) in the remaining patients. CONCLUSION Gross total resection is the gold standard treatment for patients with intraspinal nerve sheath tumors. In a time of limited health care resources, we recommend that follow-up be focused on the subgroup of patients with a high risk of recurrence. The benefit of long-term, yearly magnetic resonance imaging follow-up with respect to recurrence in nonneurofibromatosis patients undergoing gross total resection of a single schwannoma is, in our opinion, questionable. 1NF2, neurofibromatosis 2NST, nerve sheath tumorOS, overall survivalPFS, progression-free survivalSTR, subtotal resectionWHO, World Health Organization.
- Published
- 2015
24. Seizure outcomes in relation to the extent of resection of the perifocal fluorodeoxyglucose and flumazenil PET abnormalities in anteromedial temporal lobectomy
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Torsten Danfors, Jugoslav Ivanovic, Marjan Makki Mikkelsen, Pål G. Larsson, Christopher Coello, Arild Egge, Are Hugo Pripp, Bård Krossnes, Milo Stanišić, John K. Hald, and Einar Heminghyt
- Subjects
Adult ,Flumazenil ,Male ,medicine.medical_specialty ,Neurology ,Adolescent ,Neurologi ,medicine.medical_treatment ,Clinical Neurology ,Temporal lobe ,18F-FDG-PET ,Epilepsy ,Fluorodeoxyglucose F18 ,Seizures ,medicine ,Humans ,Child ,Temporal lobe epilepsy ,Anterior temporal lobectomy ,Neuroradiology ,Fluorodeoxyglucose ,medicine.diagnostic_test ,business.industry ,Middle Aged ,Anterior Temporal Lobectomy ,medicine.disease ,Post-operative outcome ,Temporal Lobe ,C-11-FMZ-PET ,Epilepsy, Temporal Lobe ,Positron emission tomography ,Positron-Emission Tomography ,F-18-FDG-PET ,Female ,Surgery ,Neurology (clinical) ,Radiology ,Radiologi och bildbehandling ,Radiopharmaceuticals ,Clinical Article - Functional ,business ,Nuclear medicine ,11C-FMZ-PET ,medicine.drug ,Radiology, Nuclear Medicine and Medical Imaging - Abstract
Background The area of predominant perifocal [18F]fluorodeoxyglucose (18F-FDG) hypometabolism and reduced [11C]flumazenil (11C-FMZ) -binding on PET scans is currently considered to contain the epileptogenic zone and corresponds anatomically to the area localizing epileptogenicity in patients with temporal lobe epilepsy (TLE). The question is whether the volume of the perifocal pre-operative PET abnormalities, the extent of their resection, and the volume of the non-resected abnormalities affects the post-operative seizure outcome. Methods The sample group consisted of 32 patients with mesial temporal sclerosis who underwent anteromedial temporal lobe resection for refractory TLE. All patients had pathologic perifocal findings on both of the PET modalities as well as on the whole-brain MRI. The volumetric data of the PET and MRI abnormalities within the resected temporal lobe were estimated by automated quantitative voxel-based analysis. The obtained volumetric data were investigated in relation to the outcome subgroups of patients (Engel classification) determined at the 2-year post-operative follow-up. Results The mean volume of the pre-operative perifocal 18F-FDG- and 11C-FMZ PET abnormalities in the volumes of interest (VOI) of the epileptogenic temporal lobe, the mean resected volume of these PET abnormalities, the mean volume of the non-resected PET abnormalities, and the mean MRI-derived resected volume were not significantly related to the outcome subgroups and had a low prediction for individual freedom from seizures. Conclusions The extent of pre-surgical perifocal PET abnormalities, the extent of their resection, and the extent of non-resected abnormalities were not useful predictors of individual freedom from seizures in patients with TLE.
- Published
- 2015
25. An Injection From the Past: Fluoroscopic Evidence of Remote Injections of Radiopaque Substances
- Author
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John K. Hald, Scott M. Fishman, Carmen L. Dominguez, and Annu Navani
- Subjects
medicine.medical_specialty ,Contrast Media ,Injections, Epidural ,Lumbar vertebrae ,Degenerative disc disease ,Diagnosis, Differential ,Lumbar ,Adrenal Cortex Hormones ,Back pain ,Humans ,Medicine ,Radiculopathy ,Injections, Spinal ,Aged ,Lumbar Vertebrae ,medicine.diagnostic_test ,business.industry ,General Medicine ,medicine.disease ,Surgery ,Anesthesiology and Pain Medicine ,medicine.anatomical_structure ,Arachnoiditis ,Fluoroscopy ,Female ,Iohexol ,medicine.symptom ,Iophendylate ,business ,Myelography ,Intervertebral Disc Displacement ,Extravasation of Diagnostic and Therapeutic Materials ,medicine.drug - Abstract
Objective Although uncommon, residual effects from contrast agents used more than 2 decades ago are possible. This case report is to alert clinicians to the implications of residual oil-based ionic contrast agents in the intrathecal space. Case Report A 70-year-old female with evidence of degenerative disc disease underwent a series of lumbar epidural steroid injections. Fluoroscopy during the procedure revealed diffuse residual intrathecal iophendylate (Pantopaque) dye. We were able to demonstrate unrestricted epidural spread of 1 mL iohexol (Omnipaque 180) alongside the preexisting dye. Conclusions The goal of this case report is to highlight the potential of residual myelographic dye to complicate interventional procedures. Such residual dye can increase the level of difficulty in performing interventional pain treatments and perhaps the rate of complications associated with epidural injections, such as dural puncture. The presence of large amounts of residual oil-based intrathecal dye can lead to erroneous interpretations of the dye patterns as intraspinal lipoma or hemorrhage. As a consequence, the patient can be submitted to unnecessary diagnostic and therapeutic interventions. In addition, concerns of worsening oil-based dye-induced arachnoiditis with the use of epidural steroid injections can complicate the treatment of patients with back pain.
- Published
- 2006
26. Cerebral Microbleeds
- Author
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Thomas Jeerakathil, Alexa S. Beiser, Charles DeCarli, Joseph M. Massaro, Rhoda Au, Carlos S. Kase, John K. Hald, and Philip A. Wolf
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Male ,Apolipoprotein E ,medicine.medical_specialty ,Pathology ,Blood Pressure ,Angiopathy ,Apolipoproteins E ,Sex Factors ,Framingham Heart Study ,Risk Factors ,Internal medicine ,Diabetes mellitus ,Humans ,Medicine ,Risk factor ,Stroke ,Aged ,Advanced and Specialized Nursing ,business.industry ,Microcirculation ,Microangiopathy ,Brain morphometry ,Age Factors ,Brain ,Middle Aged ,medicine.disease ,Lipids ,Magnetic Resonance Imaging ,Cardiovascular Diseases ,Cerebrovascular Circulation ,Cardiology ,Female ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,business ,Intracranial Hemorrhages - Abstract
Background and Purpose— Cerebral microbleeds (CMBs) are areas of low signal intensity on gradient echo T2*-weighted magnetic resonance imaging (T2*MRI) corresponding to hemosiderin deposits in the perivascular space. Microangiopathy from atherosclerosis or amyloid angiopathy might lead to the formation of these lesions; therefore, there may be associations between CMBs and cardiovascular risk factors, APOE allele status, and brain morphology. We examined these relationships in the Framingham Study (FHS). Methods— In 472 subjects from the FHS Offspring and Cohort, we related CMB status to age, sex, systolic blood pressure, total cholesterol and high-density lipoprotein cholesterol (HDL-C) levels, smoking, diabetes, total hemispheric brain volume, white matter hyperintensity volume (WMHV), and APOE allele status. Results— Overall prevalence of CMBs was 4.7%, but CMBs were more prevalent with advanced age and male sex. Blood pressure, brain volume, and WMHV were related to CMBs in crude analysis but not after adjustment for age and sex. There were no significant relationships demonstrated between CMBs and APOE allele status, cholesterol, smoking, or diabetes. Conclusions— There is a low prevalence of CMBs in the community and a strong relationship with increasing age and male sex. We found no independent relationships with cardiovascular risk factors, APOE status, brain volumes, or WMH.
- Published
- 2004
27. Delayed Diffusion-Weighted MR Abnormality In a Patient With an Extensive Acute Cerebral Hypoxic Injury. A case report
- Author
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John K. Hald, Arthur B. Dublin, James A. Brunberg, and Sandra L. Wootton-Gorges
- Subjects
Pathology ,medicine.medical_specialty ,Radiological and Ultrasound Technology ,Injury control ,Vascular disease ,business.industry ,Ischemia ,Poison control ,Autopsy ,General Medicine ,Hypoxia (medical) ,medicine.disease ,Mr imaging ,Surgery ,Central nervous system disease ,Brain ischemia ,Acute cerebral infarction ,Medicine ,Hypoxic brain injury ,Radiology, Nuclear Medicine and imaging ,Radiology ,medicine.symptom ,Abnormality ,business - Abstract
Diffusion-weighted (DW) MR imaging usually identifies acute cerebral infarction injury in symptomatic patients. We report a patient with severe hypoxic brain injury following suicide attempt by hanging, but with normal DW MR imaging 5–6 h after the event. Follow-up DW MR imaging 3 days after the event, and subsequent autopsy, revealed extensive cerebral anoxic injury.
- Published
- 2003
28. Prognostic factors in patients with symptomatic spinal metastases and normal neurological function
- Author
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Olga Zaikova, John K. Hald, Ulf E Kongsgaard, Knut Håkon Hole, M. D. Switlyk, Kjetil Knutstad, and Sigmund Skjeldal
- Subjects
Oncology ,Adult ,Male ,medicine.medical_specialty ,Multivariate analysis ,Lung Neoplasms ,medicine.medical_treatment ,Analgesic ,Breast Neoplasms ,Spinal canal stenosis ,Disease ,Internal medicine ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Neoplasm Metastasis ,Aged ,Aged, 80 and over ,Spinal Neoplasms ,medicine.diagnostic_test ,business.industry ,Albumin ,Prostatic Neoplasms ,Magnetic resonance imaging ,Middle Aged ,Prognosis ,Magnetic Resonance Imaging ,Survival Analysis ,Surgery ,Radiation therapy ,Female ,business ,Spinal metastases - Abstract
Aims To evaluate potential prognostic factors for predicting survival after radiotherapy in patients with painful spinal metastases and normal neurological function. Materials and methods In total, 173 patients were included. The following prognostic factors were assessed: primary cancer site, age, gender, albumin and haemoglobin levels, Karnofsky performance status (KPS), analgesic use, pain intensity, number of extraspinal bone metastases and visceral metastases, presence of tumour-conditioned spinal canal stenosis and metastatic spinal cord compression, and extension of spinal metastatic disease on magnetic resonance imaging (MRI). Ongoing systemic treatment, use of bisphosphonates and response to radiotherapy were also evaluated. A simple scoring system for predicting survival was used. Results The following predictive factors were found to be significant in multivariate analysis: primary cancer site, KPS, albumin level, number of visceral metastases and analgesic use. Three survival groups were proposed. The overall survival probabilities for groups 1–3 were 13, 46 and 94% at 6 months; 4, 28 and 79% at 12 months, respectively. The median survival times for groups 1–3 were 2.1, 5.5 and 24.9 months, respectively ( P Conclusion The pretreatment albumin level was a significant prognostic indicator for survival. Similarly, the primary cancer site, KPS and number of visceral metastases were associated with survival; these findings were consistent with the results of previous studies. The pretreatment analgesic use was significant using the univariate and multivariate analyses and this factor can be verified in future trials. Self-reported pain intensity, pain response to radiotherapy and MRI findings did not influence survival times.
- Published
- 2014
29. CTA IN PATIENTS WITH ACUTE SUBARACHNOID HAEMORRHAGE. A comparative study with selective, digital angiography and blinded, independent review
- Author
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H. K. Pedersen, Karl-Fredrik Lindegaard, I. M. Anke, Søren Jacob Bakke, Iver A. Langmoen, I. O. Skalpe, R. Sagsveen, John K. Hald, and P. H. Nakstad
- Subjects
medicine.medical_specialty ,Kappa value ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,Vascular disease ,Vascular anatomy ,business.industry ,musculoskeletal, neural, and ocular physiology ,Retrospective cohort study ,General Medicine ,Digital subtraction angiography ,Diagnostic evaluation ,medicine.disease ,Central nervous system disease ,Aneurysm ,Angiography ,medicine ,Radiology, Nuclear Medicine and imaging ,Subarachnoid haemorrhage ,Intra-arterial digital subtraction angiography ,In patient ,cardiovascular diseases ,Radiology ,business ,psychological phenomena and processes - Abstract
Purpose: Minimal- or non-invasive methods replacing intra-arterial digital subtraction angiography (IA-DSA) would be of great importance in patients suffering from acute subarachnoid haemorrhage (SAH). The aims of this study were to compare CTA with IA-DSA in patients with acute SAH, to compare CTA interpretations with those of blinded, independent reviewers and to evaluate improvement in CTA diagnostics after 1 year of experience with CTA. Material and Method: During 2 years 162 patients with SAH underwent CTA as well as IA-DSA. Independent blinded review of 77 patients was performed for 1 year. Results: Totally 144 aneurysms were demonstrated in 119 patients at IA-DSA, while 43 patients had normal intracranial arteries. Initially 131 aneurysms were detected at CTA while 2 normal, tortuous arteries were misinterpreted as aneurysms, giving a sensitivity of 91% and a specificity of 95%. At independent blinded review the observer agreement was 87% and the kappa value 0.68. Conclusion: CTA in SAH is of great value in demonstrating vascular anatomy and the exact size of an aneurysm. However, IA-DSA is still needed for diagnostic evaluation in aneurysms smaller than 5 mm in diameter, especially in those located near bony structures.
- Published
- 2001
30. Radiotherapy for spinal metastases from breast cancer with emphasis on local disease control and pain response using repeated MRI
- Author
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Marta D. Switlyk, John K. Hald, Øyvind S. Bruland, Olga Zaikova, Sigmund Skjeldal, and Therese Seierstad
- Subjects
medicine.medical_specialty ,Pathology ,lcsh:Diseases of the musculoskeletal system ,Metastatic lesions ,medicine.medical_treatment ,lcsh:RC254-282 ,Breast cancer ,Medicine ,In patient ,medicine.diagnostic_test ,Pain response ,Radiotherapy ,business.industry ,Radiation field ,Bone metastases ,Magnetic resonance imaging ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,medicine.disease ,Radiation therapy ,Oncology ,Local disease ,Radiology ,lcsh:RC925-935 ,business ,Spinal metastases ,Research Article ,MRI - Abstract
Aims: To evaluate metastatic lesions within the radiation field using repeated magnetic resonance imaging (MRI) and to compare the imaging findings with pain response following radiotherapy (RT) in patients with spinal metastases (SM) from breast cancer. Material and methods: 32 Patients with SM from breast cancer admitted for fractionated RT were included in this study. MRI examinations of the spine were scored for the extent of bone metastases, epidural disease and the presence and severity of vertebral fractures. Clinical response was defined according to the updated international consensus on palliative RT endpoints. Results: At 2 and 6 months after RT, 38% and 44% of the patients were classified as responders. None of the patients developed motor deficits. Importantly, a decrease in the intraspinal tumor volume after RT was reported in all patients. Only 6% of the patients showed bone metastases progression within the RT field, whereas 60% of the patients showed disease progression outside the RT portals. 5 Patients developed new fractures after RT, and fracture progression was observed in 21 of the 38 lesions (55%). The pain response to RT did not correlate with the presence of vertebral body fracture before RT, fracture progression or other recorded MRI features of metastatic lesions. Conclusion: RT provided excellent local tumor control in patients with SM. Most patients benefit from RT even in cases of progressive vertebral fracture. Pain response was not associated with imaging findings and MRI cannot be used to select patients at risk of not responding to RT.
- Published
- 2013
31. Improving postoperative MR imaging of pituitary macroadenomas: comparison of full and reduced dose of gadopentetate dimeglumine
- Author
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R. L. Dunn, P. H. Nakstad, H. K. Pedersen, John K. Hald, S. J. Bakke, and O. P. Eldevik
- Subjects
Adenoma ,Adult ,Gadolinium DTPA ,Male ,medicine.medical_specialty ,Contrast Media ,medicine ,Humans ,Pituitary Neoplasms ,Radiology, Nuclear Medicine and imaging ,Prospective Studies ,Prospective cohort study ,Aged ,Neuroradiology ,Aged, 80 and over ,Postoperative Care ,medicine.diagnostic_test ,business.industry ,Ultrasound ,Interventional radiology ,General Medicine ,Middle Aged ,Reduced dose ,Magnetic Resonance Imaging ,Mr imaging ,Coronal plane ,Total dose ,Female ,Radiology ,business ,Nuclear medicine - Abstract
The aim of this study was to evaluate the efficacy of contrast-medium (CM)-enhanced MR imaging of operated pituitary macroadenomas with reduced dose of gadopentetate dimeglumine. In a prospective study 18 patients were examined with coronal T1-weighted MR imaging prior to and following intravenous CM injections. Two sets of contrast-enhanced coronal images were obtained in each patient; the first set after 50 % of the recommended dose of 0.1 mmol/kg body weight (b. w.) had been administered, and the second set immediately after additional CM had been given to make up a total dose of 0.1 mmol/kg b. w. The images were evaluated by three neuroradiologists. The SIPAP classification system was used to evaluate tumour extension, whereas tumour margin conspicuity was scored using an arbitrary scale of 1–5 (1 = indistinct, 5 = well defined). Signal intensity measurements obtained from the most enhancing part of the adenomas demonstrated increased enhancement with increased CM dose. Tumour delineation scores were significantly better on the reduced- and full-dose images than on pre-CM injection images, but, with one exception, tumour extension was identified as the same on all imaging sequences. Postoperative MR imaging of large macroadenoma residues can routinely be performed without intravenous CM. When CM is indicated a reduced dose of gadopentetate dimeglumine should provide sufficient diagnostic information.
- Published
- 2000
32. Limited utility of current MRI criteria for distinguishing multiple sclerosis from common mimickers: primary and secondary CNS vasculitis, lupus and Sjogren's syndrome
- Author
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John K. Hald, Wesley O. Johnson, David P. Richman, Mark A. Agius, and Susan S. Kim
- Subjects
Adult ,Male ,Pathology ,medicine.medical_specialty ,Multiple Sclerosis ,Adolescent ,Diagnosis, Differential ,Young Adult ,Image Interpretation, Computer-Assisted ,medicine ,Primary CNS Vasculitis ,Humans ,Lupus Erythematosus, Systemic ,In patient ,Vasculitis, Central Nervous System ,Aged ,Retrospective Studies ,Aged, 80 and over ,Systemic lupus erythematosus ,medicine.diagnostic_test ,business.industry ,Multiple sclerosis ,Magnetic resonance imaging ,Bayes Theorem ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Secondary CNS Vasculitis ,Sjogren's Syndrome ,Neurology ,Female ,Neurology (clinical) ,Sjogren s ,Vasculitis ,business - Abstract
Background: Magnetic resonance imaging (MRI) criteria play an important role in making an earlier diagnosis of multiple sclerosis (MS) in patients presenting with clinically isolated syndrome. Objective: The objective of this paper is to determine whether MRI criteria may be used to distinguish MS from primary and secondary central nervous system (CNS) vasculitis, lupus, and Sjogren’s syndrome. Methods: MRI criteria were applied retrospectively to images for patients with clinically definite MS (CDMS), primary CNS vasculitis, secondary CNS vasculitis, and autoimmune disorders including systemic lupus erythematosus (SLE) and Sjogren’s syndrome. Classical statistics and Bayesian analyses were performed. Results: Overall modified Barkhof’s MRI criteria were statistically significant in distinguishing CDMS (60%) from SLE/Sjogren’s syndrome (17%, p = 0.0173) but not in distinguishing CDMS from primary CNS vasculitis (50%, p = 0.7376) or secondary CNS vasculitis (58%, p = 1.0000). Four of the five other MRI criteria tested were demonstrated to be superior to modified Barkhof’s criteria in predicting MS: nine or more T2 lesions (a component of Barkhof’s criteria), one or more ovoid periventricular T2 lesions, one or more perpendicular periventricular T2 lesions, and one or more T2 lesions larger than 6 mm. Conclusions: MRI criteria, including the modified Barkhof’s criteria, were unsuccessful in distinguishing MS from primary CNS vasculitis or secondary CNS vasculitis and mildly successful in distinguishing MS from SLE/Sjogren’s syndrome.
- Published
- 2013
33. MRI and neurological findings in patients with spinal metastases
- Author
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Therese Seierstad, M. D. Switlyk, John K. Hald, K. Knutstad, Sigmund Skjeldal, Knut Håkon Hole, and O. Zaikova
- Subjects
Adult ,Epidural Space ,Male ,medicine.medical_specialty ,Motor Activity ,Severity of Illness Index ,Young Adult ,Metastatic spinal cord compression ,Severity of illness ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Neurological findings ,In patient ,Prospective Studies ,Prospective cohort study ,Aged ,Aged, 80 and over ,Neurologic Examination ,Spinal Neoplasms ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,General Medicine ,Middle Aged ,Magnetic Resonance Imaging ,Spine ,Surgery ,Investigation methods ,Female ,Radiology ,business ,Spinal metastases ,Spinal Canal ,Spinal Cord Compression - Abstract
Magnetic resonance imaging (MRI) is the recommended primary investigation method for metastatic spinal cord compression (MSCC). Initiating treatment before the development of motor deficits is essential to preserve neurological function. However, the relationship between MRI-assessed grades of spinal metastatic disease and neurological status has not been widely investigated.To analyze the association between neurological function and MRI-based assessment of the extent of spinal metastases using two different grading systems.A total of 284 patients admitted to our institution for initial radiotherapy or surgery for symptomatic spinal metastases were included in the study. Motor and sensory deficits were categorized according to the Frankel classification system. Pre-treatment MRI evaluations of the entire spine were scored for the extent of spinal metastases, presence and severity of spinal cord compression, and nerve root compression. Two MRI-based scales were used to evaluate the degree of cord compression and spinal canal narrowing and relate these findings to neurological function.Of the patients included in the study, 28 were non-ambulatory, 49 were ambulatory with minor motor deficits, and 207 had normal motor function. Spinal cord compression was present in all patients with Frankel scores of B or C, 23 of 35 patients with a Frankel score of D (66%), and 48 of 152 patients with a Frankel score of E (32%). The percentage of patients with severe spinal canal narrowing increased with increasing Frankel grades. The grading according to the scales showed a significant association with the symptoms according to the Frankel scale (P0.001).In patients with neurological dysfunction, the presence and severity of impairment was associated with the epidural tumor burden. A significant number of patients had radiological spinal cord compression and normal motor function (occult MSCC).
- Published
- 2012
34. Machine learning in preoperative glioma MRI: survival associations by perfusion-based support vector machine outperforms traditional MRI
- Author
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Kyrre E, Emblem, Paulina, Due-Tonnessen, John K, Hald, Atle, Bjornerud, Marco C, Pinho, David, Scheie, Lothar R, Schad, Torstein R, Meling, and Frank G, Zoellner
- Subjects
Adult ,Aged, 80 and over ,Male ,Support Vector Machine ,Brain Neoplasms ,Reproducibility of Results ,Glioma ,Middle Aged ,Image Enhancement ,Prognosis ,Sensitivity and Specificity ,Survival Rate ,Young Adult ,Treatment Outcome ,Image Interpretation, Computer-Assisted ,Preoperative Care ,Humans ,Female ,Algorithms ,Magnetic Resonance Angiography ,Aged ,Retrospective Studies - Abstract
To retrospectively evaluate the performance of an automatic support vector machine (SVM) routine in combination with perfusion-based dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) for preoperative survival associations in patients with gliomas and compare our results to traditional MRI.The study was approved by the Ethics Committee and informed consent was signed. Structural, diffusion- and perfusion-weighted MRI was performed at 1.5-T preoperatively in 94 adult patients (49 males, 45 females, 23-82 years; mean 51 years) later diagnosed with a primary glioma. Patients were randomly assigned in training and test datasets and the resulting DSC-based survival associations by SVM were compared to traditional MRI features including contrast-agent enhancement, perfusion- and diffusion-weighted imaging, tumor size, and location. The results were adjusted for age, neurological status, and postoperative factors associated with survival, including surgery and adjuvant therapy.For 1- (26/33 alive, 11/14 deceased), 2- (15/21, 21/26), 3- (12/16, 27/31) and 4- (12/15, 28/32) year survival associations in the test dataset (47 patients), the SVM routine was the only biomarker to consistently associate with survival (Cox; P0.001).The automatic machine learning routine presented in our study may provide the operator with a reliable instrument for assessing survival in patients with glioma.
- Published
- 2012
35. The pulmonary artery in patients with Marfan syndrome: a cross-sectional study
- Author
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Hans-Jørgen Smith, Rigmor Lundby, John K. Hald, Are Hugo Pripp, and Svend Rand-Hendriksen
- Subjects
Marfan syndrome ,Adult ,Male ,medicine.medical_specialty ,Aortic Diseases ,Pulmonary Artery ,Severity of Illness Index ,Marfan Syndrome ,Internal medicine ,medicine.artery ,Ascending aorta ,medicine ,Prevalence ,Humans ,Genetics (clinical) ,Aorta ,Body surface area ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Trunk ,Magnetic Resonance Imaging ,Sagittal plane ,medicine.anatomical_structure ,Cross-Sectional Studies ,ROC Curve ,Case-Control Studies ,Pulmonary artery ,Multivariate Analysis ,Cardiology ,Female ,Radiology ,business ,Tomography, X-Ray Computed ,Dilatation, Pathologic - Abstract
The objectives of this study were to establish the prevalence of pulmonary artery dilatation in Marfan syndrome using modern radiological methods and to correlate the diameter of the vessel with aortic disease. Magnetic resonance or computed tomography imaging of the pulmonary artery and aorta was performed in 87 patients with proven Marfan syndrome. Diameters of the root and trunk of the pulmonary artery and of the aortic root were measured perpendicular to the long axes of the vessels. Pulmonary artery diameters were measured on axial images, and aortic diameters were assessed on oblique sagittal images. As compared with normal values in the literature, 47 of the 87 patients (54%) had widening of the trunk of the pulmonary artery (≥30 mm). Of these 47, 15% had no sign of disease of the ascending aorta. The mean (SD) ratio between the diameters of the root and trunk of the pulmonary artery was 1.18 (0.155). Multivariate analysis showed that surgery of the ascending aorta and high body surface area were associated with dilatation of the trunk of the pulmonary artery. Pulmonary artery dilatation is present in a high proportion of patients with Marfan syndrome as assessed using cutoff values based on measurements in the normal population. Severe disease of the ascending aorta correlates significantly with pulmonary artery trunk dilatation in patients with Marfan syndrome. Genet Med 2012:14(11):922–927
- Published
- 2012
36. MR Imaging of Pituitary Region Lesions with Gadodiamide Injection
- Author
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Søren Jacob Bakke, John K. Hald, I. O. Skalpe, and P. H. Nakstad
- Subjects
Pituitary gland ,medicine.medical_specialty ,Diagnostic information ,Radiological and Ultrasound Technology ,business.industry ,Gadodiamide ,General Medicine ,Mr imaging ,T2 value ,Contrast medium ,medicine.anatomical_structure ,Precontrast ,medicine ,Radiology, Nuclear Medicine and imaging ,Radiology ,Mr images ,business ,Nuclear medicine ,medicine.drug - Abstract
Twelve patients with known or suspected pituitary lesions underwent MR imaging with gadodiamide injection at a dose of 0.1 (n = 5) or 0.3 (n = 7) mM/kg. Six of the patients were also studied with 0.1 mM/kg gadopentetate dimeglumine. Consistent with previous reports gadodiamide injection was found to be a safe and effective contrast medium for MR imaging of the pituitary region. No additional diagnostic information was obtained using 0.3 mM/kg gadodiamide injection compared to 0.1 mM/kg gadopentetate dimeglumine in the same patients. The high dose (0.3 mM/kg) gadodiamide injection in 7 patients did not shorten the T2 value sufficiently to overwhelm the T1 shortening and leave pathologic lesions hypointense compared to precontrast studies. With the comparable relaxivities of gadodiamide injection and gadopentetate dimeglumine, similarities in results have to be expected when using these media for MR image enhancement.
- Published
- 1994
37. Assessment of pituitary adenoma volumetric change using longitudinal MR image registration
- Author
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Atle Bjørnerud, John K. Hald, Anders M. Dale, Dominic Holland, Geir Ringstad, and Kyrre E. Emblem
- Subjects
Adenoma ,Adult ,Male ,medicine.medical_specialty ,Contrast Media ,Pituitary neoplasm ,Sensitivity and Specificity ,Statistics, Nonparametric ,McNemar's test ,Imaging, Three-Dimensional ,Pituitary adenoma ,Image Interpretation, Computer-Assisted ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Pituitary Neoplasms ,Longitudinal Studies ,Prospective Studies ,Neuroradiology ,Aged ,medicine.diagnostic_test ,business.industry ,Visual comparison ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,ROC Curve ,Area Under Curve ,Female ,Neurology (clinical) ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Change detection - Abstract
Change detection is a crucial factor in monitoring of slowly evolving pathologies. The objective of the study was to test a semi-automatic method applied on longitudinal MRI monitoring of volume change in pituitary macroadenomas. The proposed method is based on a visual comparison of geometrically corrected, co-registered, intensity-normalized contrast-enhanced (CE) 3D GRE T1-weighted images. Qualitative volume changes based on this applied method were compared with experts’ readings of conventional pre- and post-CE 2D T1-weighted images. Magnetic resonance (MR) imaging was performed two to four times in 13 patients with a total combination of 29 time points. Compared to conventional 2D MR readings, a diagnosis of tumor growth (yes/no) was changed in 5 of 13 patients (38%) at 9 of the 29 combinations of time points (31%) using the 3D-based semi-automatic method. With manual tumor tracings as reference, McNemar’s test showed a significant difference between the two methods. Visual comparison of geometrically corrected, intensity-normalized, and affine-aligned longitudinal 3D images may enable more accurate assessment of qualitative volumetric change in pituitary adenomas than conventional reading of 2D images.
- Published
- 2011
38. A double-blind study to evaluate the efficacy and tolerability of a higher dose (0.3 mmol per kg bw) of gadodiamide injection as a contrast medium for MRI
- Author
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Søren Jacob Bakke, M. G. Svaland, I. O. Skalpe, and John K. Hald
- Subjects
Radiological and Ultrasound Technology ,medicine.diagnostic_test ,business.industry ,Gadodiamide ,Biophysics ,Magnetic resonance imaging ,Double blind study ,Contrast medium ,Blood chemistry ,Tolerability ,Mole ,medicine ,Radiology, Nuclear Medicine and imaging ,Adverse effect ,business ,Nuclear medicine ,medicine.drug - Abstract
Gadodiamide injection was administered intravenously to 48 patients with known or suspected central nervous system (CNS) lesions undergoing magnetic resonance imaging (MRI). Two parallel groups were examined to evaluate the efficacy and safety of single doses of 0.1 and 0.3mmol per kg bw. The principal measures of efficacy were diagnostic yield of MR images, the overall contrast enhancement and the contrast index (CI). Adverse events and serum bilirubin level were the main safety parameters. Nineteen patients in each dose group displayed contrast enhancement of the MR image (1.5 T Siemens Gyroscan MR unit;T1TR/TE=560−650/15−25 ms;T2:TR/TE=2200−3100/22−90 ms). The CI increased by 47.3% in the 0.1 mmol/kg bw group and by 86.5% in the 0.3 mmol per kg bw group compared to the pre-contrast scan. Four patients in the 0.1 mmol per kg bw group and seven in the 0.3 mmol per kg bw group had their management changed by new information from the post-contrast scan and four patients in each dose group had their diagnosis altered following the post-contrast scan. Two patients in the 0.3 mmol per kg bw group experienced injection-associated discomfort. There were no other adverse events reported during the 24 h follow-up period. No clinically significant changes in serum bilirubin or other parameters of blood chemistry or haematology were observed. The study demonstrates that the safety profile of gadodiamide injection 0.3 mmol per kg bw is similar to that of 0.1 mmol per kg bw and that, at both doses, gadodiamide injection is a safe and effective contrast medium for use in patients undergoing MRI on the CNS. Slightly more patients had an improvement in diagnostic yield with the 0.3 mmol per kg bw dose and the CI was increased to a greater extent in this group, showing that when greater contrast is required the higher dose of gadodiamide injection may be considered. Further studies in selected patient groups, and with the use of different doses in the same patient are necessary to evaluate the diagnostic value of higher doses.
- Published
- 1993
39. The expression of E-cadherin in somatotroph pituitary adenomas is related to tumor size, invasiveness, and somatostatin analog response
- Author
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Olivera Casar Borota, Stine Lyngvi Fougner, Jens P. Berg, Jens Bollerslev, Tove Lekva, and John K. Hald
- Subjects
Adult ,Male ,Pituitary gland ,medicine.medical_specialty ,Somatotropic cell ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Context (language use) ,Biochemistry ,Metastasis ,Endocrinology ,Translational Highlights from Jcem ,Pituitary adenoma ,Internal medicine ,medicine ,Humans ,Neoplasm Invasiveness ,Pituitary Neoplasms ,Insulin-Like Growth Factor I ,Molecular Biology ,Cadherin ,business.industry ,Biochemistry (medical) ,Adhesion ,General Medicine ,Middle Aged ,medicine.disease ,Cadherins ,Phenotype ,Immunohistochemistry ,Magnetic Resonance Imaging ,Peptide Fragments ,medicine.anatomical_structure ,Growth Hormone ,Acromegaly ,Female ,business ,Somatostatin - Abstract
Context: Appropriate cell-to-cell adhesion is fundamental for the epithelial phenotype of pituitary cells. Loss of the adhesion protein E-cadherin has been associated with invasiveness, metastasis, and poor prognosis in cancers of epithelial origin. In somatotroph adenomas, a variable and reduced expression of E-cadherin has been demonstrated. In addition, nuclear translocation of E-cadherin was found to correlate with pituitary tumor invasion. Objective: The objective was to examine the protein expression of E-cadherin in somatotroph pituitary adenomas in relation to adenoma size, invasiveness, and somatostatin analog (SMS) efficacy. Patients and Methods: Eighty-three patients were included, and 29 were treated preoperatively with SMS. Adenoma E-cadherin protein expression was analyzed by Western blot (61 patients) and immunohistochemistry (IHC) (80 patients) with antibodies directed against both extracellular and intracellular domains (IHC). The acute (direct surgery group) and long-term (preoperatively treated group) SMS responses were evaluated. Baseline tumor volume and invasiveness were measured on magnetic resonance imaging scans. Results: Membranous E-cadherin was lost in several adenomas. Nine of these were nuclear E-cadherin positive. The E-cadherin protein expression correlated negatively to tumor size and positively to acute SMS response. Low E-cadherin levels (preoperatively treated group only) and loss of membranous E-cadherin correlated to tumor invasiveness. The E-cadherin level correlated positively to tumor reduction after SMS treatment, and adenomas with nuclear E-cadherin staining had lower IGF-I reduction and tumor shrinkage. Preoperatively treated adenomas had reduced E-cadherin protein levels, but the IHC expression was unaltered. Conclusion: Reduced E-cadherin expression may correlate to a dedifferentiated phenotype in the somatotroph pituitary adenomas.
- Published
- 2010
40. Comparison of 12-Bit and 8-Bit Gray Scale Resolution in Mr Imaging of the CNS
- Author
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John K. Hald, Hans-Jørgen Smith, Andreas Abildgaard, G. Moen, Bjarne Smevik, B. Rudenhed, and Søren Jacob Bakke
- Subjects
Radiological and Ultrasound Technology ,Receiver operating characteristic ,business.industry ,Image quality ,Pattern recognition ,Image processing ,General Medicine ,Grayscale ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,Digital image ,0302 clinical medicine ,030220 oncology & carcinogenesis ,Color depth ,Medicine ,Radiology, Nuclear Medicine and imaging ,Screen reading ,Artificial intelligence ,Nuclear medicine ,business ,Image resolution - Abstract
A reduction in gray scale resolution of digital images from 12 to 8 bits per pixel usually means halving the storage space needed for the images. Theoretically, important diagnostic information may be lost in the process. We compared the sensitivity and specificity achieved by 4 radiologists in reading laser-printed films of original 12-bit MR images and cathode ray tube displays of the same images which had been compressed to 8 bits per pixel using a specially developed computer program. Receiver operating characteristic (ROC) curves showed no significant differences between film reading and screen reading. A paired 2-tailed t-test, applied on the data for actually positive cases, showed that the combined, average performance of the reviewers was significantly better at screen reading than at film reading. No such differences were found for actually negative cases. Some individual differences were found, but it is concluded that gray scale resolution of MR images may be reduced from 12 to 8 bits per pixel without any significant reduction in diagnostic information.
- Published
- 1992
41. Carotid-Cavernous Fistula Treated with Detachable Balloon during Bilateral Transcranial Doppler Monitoring of Middle Cerebral Arteries
- Author
-
P. H. Nakstad, W. Sorteberg, and John K. Hald
- Subjects
medicine.medical_specialty ,Radiological and Ultrasound Technology ,business.industry ,Fistula ,Cerebral arteries ,Arteriovenous fistula ,General Medicine ,medicine.disease ,Balloon ,Surgery ,Transcranial Doppler ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,030220 oncology & carcinogenesis ,Cavernous sinus ,medicine ,Balloon dilation ,cardiovascular system ,Radiology, Nuclear Medicine and imaging ,Radiology ,business ,Carotid-cavernous fistula - Abstract
A traumatic carotid-cavernous fistula was closed with a silicone detachable balloon. Prior to the closure of the fistula, clinical and transcranial Doppler testing was performed in order to evaluate the consequences of a possible occlusion of the carotid artery. A newly developed Doppler technique with bilateral simultaneous velocity recordings of the middle cerebral arteries was useful during the procedure. The detachable balloon was effective in closing the fistula, but collapse of the balloon and the development of an extradural aneurysm was found at control examinations.
- Published
- 1992
42. Embolization of intracranial arteriovenous malformations and fistulas with polyvinyl alcohol particles and platinum fibre coils
- Author
-
Søren Jacob Bakke, P. H. Nakstad, and John K. Hald
- Subjects
Adult ,Intracranial Arteriovenous Malformations ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Polyvinyl alcohol ,Embolic Agent ,chemistry.chemical_compound ,Dural arteriovenous fistulas ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Complication rate ,Embolization ,Cerebral Hemorrhage ,Neurologic Examination ,Epilepsy ,integumentary system ,business.industry ,Embolization Therapy ,Arteriovenous malformation ,Prostheses and Implants ,Middle Aged ,medicine.disease ,Embolization, Therapeutic ,Cerebral Angiography ,chemistry ,Polyvinyl Alcohol ,Arteriovenous Fistula ,Female ,Neurology (clinical) ,Radiology ,Cardiology and Cardiovascular Medicine ,business - Abstract
In order to reduce the recanalization rate of arteriovenous malformations and multiple dural arteriovenous fistulas, embolization was carried out with polyvinyl alcohol (PVA) particles combined with platinum fibre coils in 20 patients. The malformation was occluded more effectively than by PVA alone. Distal deposition of the emboli was obtained by improved steerable catheters (Tracker-18-unibody) and guidewires. The complication rate was lower than usually reported from studies using glue as embolic agent. It was concluded that the combination of PVA and fibre coils enhances the safety and effectiveness of embolization therapy and reduces the frequency of recanalization of intracranial AVMs.
- Published
- 1992
43. MR imaging of pituitary macroadenomas before and after transsphenoidal surgery
- Author
-
I. O. Skalpe, Søren Jacob Bakke, P. H. Nakstad, John K. Hald, and T. Kollevold
- Subjects
Transsphenoidal surgery ,medicine.medical_specialty ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,business.industry ,medicine.medical_treatment ,Sphenoid bone ,Magnetic resonance imaging ,General Medicine ,Pituitary neoplasm ,Mr imaging ,Sagittal plane ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Coronal plane ,Medicine ,Radiology, Nuclear Medicine and imaging ,Mr studies ,Radiology ,business - Abstract
MR findings before and after transsphenoidal surgery were evaluated in 6 cases. T1-weighted (TR/TE 600/20) sagittal and coronal images with 2 or 4 acquisitions were obtained, using 3-mm slice thickness and 0.3-mm interslice gaps. Of 18 MR examinations, 13 included coronal i.v. contrast medium enhanced images. Image quality, sinus cavernosus invasion, identification of normal pituitary tissue and tumor size were examined. All MR studies clearly demonstrated the macroadenomas whether 2 or 4 acquisitions were used, and whether i.v. contrast medium was administered or not. Surgically confirmed sinus cavernosus infiltration was seen in 4 patients. The pituitary stalk was identified separate from the tumor in 2 patients, and the gland in one. There was reduction in tumor size over time, indicating that final radiologic assessment after transsphenoidal surgery is best performed 4 to 6 months postoperatively. It should not be necessary to routinely include i.v. contrast medium injection in the postoperative evaluation of macroadenomas.
- Published
- 1992
44. Low frequency ofVHLgermline mutations in Norwegian patients presenting with isolated central nervous system hemangioblastomas â a population-based study
- Author
-
Thomas Schreiner, John K. Hald, Per Arne Andresen, Ketil Heimdal, Pål Rønning, Eirik Helseth, and David Scheie
- Subjects
Adult ,Male ,Pathology ,medicine.medical_specialty ,von Hippel-Lindau Disease ,endocrine system diseases ,DNA Mutational Analysis ,Population ,urologic and male genital diseases ,Central Nervous System Neoplasms ,Central nervous system disease ,Germline mutation ,Renal cell carcinoma ,Hemangioblastoma ,Genotype ,medicine ,Humans ,Genetic Testing ,Von Hippel–Lindau disease ,education ,neoplasms ,Germ-Line Mutation ,Genetic testing ,education.field_of_study ,medicine.diagnostic_test ,Norway ,business.industry ,Genetic Carrier Screening ,General Medicine ,Kidney Diseases, Cystic ,Middle Aged ,medicine.disease ,female genital diseases and pregnancy complications ,Cross-Sectional Studies ,Neurology ,Female ,Neurology (clinical) ,business - Abstract
Ronning P, Andresen PA, Hald JK, Heimdal K, Scheie D, Schreiner T, Helseth E. Low frequency of VHL germline mutations in Norwegian patients presenting with isolated central nervous system hemangioblastomas – a population-based study. Acta Neurol Scand: 2010: 122: 124–131. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objectives – Explore the genetic and clinical incidence of von Hippel–Lindau disease in patients presenting with isolated central nervous system hemangioblastomas. Results – We report a 3.2% (1/31) and 25% (8/32) incidence of genetic and clinical VHL, respectively. One patient tested positive for a VHL mutation that has not previously been reported. This genotype phenotypically predicts VHL type 2B. We had seven patients with renal cysts. In a total follow-up of 33 person years, none of these cysts progressed to renal cell carcinoma. Conclusion – von Hippel-Lindau disease anchored in germline mutations of the VHL gene is rare in the Norwegian population as opposed to clinical VHL disease, which appears to be relatively common in patients with apparently sporadic hemangioblastomas. There exists insufficient data regarding the natural history of patients with renal cysts, which makes it difficult to include or disregard these lesions as an entity of VHL disease.
- Published
- 2009
45. Automatic glioma characterization from dynamic susceptibility contrast imaging: brain tumor segmentation using knowledge-based fuzzy clustering
- Author
-
Atle Bjørnerud, Paulina Due-Tønnessen, Terje Nome, John K. Hald, Baard Nedregaard, and Kyrre E. Emblem
- Subjects
Adult ,Male ,Fuzzy clustering ,Adolescent ,Contrast Media ,Sensitivity and Specificity ,Young Adult ,Text mining ,Imaging, Three-Dimensional ,Fuzzy Logic ,Risk Factors ,Histogram ,Glioma ,medicine ,Image Processing, Computer-Assisted ,Organometallic Compounds ,Humans ,Radiology, Nuclear Medicine and imaging ,Cluster analysis ,Survival analysis ,Aged ,Observer Variation ,Receiver operating characteristic ,business.industry ,Brain Neoplasms ,Echo-Planar Imaging ,Reproducibility of Results ,Middle Aged ,medicine.disease ,Image Enhancement ,Magnetic Resonance Imaging ,Survival Analysis ,Area Under Curve ,Female ,business ,Nuclear medicine ,Dynamic susceptibility - Abstract
Purpose To assess whether glioma volumes from knowledge-based fuzzy c-means (FCM) clustering of multiple MR image classes can provide similar diagnostic efficacy values as manually defined tumor volumes when characterizing gliomas from dynamic susceptibility contrast (DSC) imaging. Materials and Methods Fifty patients with newly diagnosed gliomas were imaged using DSC MR imaging at 1.5 Tesla. To compare our results with manual tumor definitions, glioma volumes were also defined independently by four neuroradiologists. Using a histogram analysis method, diagnostic efficacy values for glioma grade and expected patient survival were assessed. Results The areas under the receiver operator characteristics curves were similar when using manual and automated tumor volumes to grade gliomas (P = 0.576–0.970). When identifying a high-risk patient group (expected survival 2 years), a higher log-rank value from Kaplan-Meier survival analysis was observed when using automatic tumor volumes (14.403; P < 0.001) compared with the manual volumes (10.650–12.761; P = 0.001–0.002). Conclusion Our results suggest that knowledge-based FCM clustering of multiple MR image classes provides a completely automatic, user-independent approach to selecting the target region for presurgical glioma characterization J. Magn. Reson. Imaging 2009;30:1–10. © 2009 Wiley-Liss, Inc.
- Published
- 2009
46. Spindle cell oncocytoma of the adenohypophysis: report of a case with marked cellular atypia and recurrence despite adjuvant treatment
- Author
-
B.W. Scheithauer, Jens Bollerslev, Jon Ramm-Pettersen, S. Lyngvi Fougner, John K. Hald, and O. Casar Borota
- Subjects
Pathology ,medicine.medical_specialty ,medicine.medical_treatment ,Galectin 3 ,Vimentin ,Biology ,Pathology and Forensic Medicine ,Pituitary Gland, Anterior ,Adjuvant therapy ,medicine ,Adenoma, Oxyphilic ,Humans ,Pituitary Neoplasms ,Nuclear atypia ,Pituitary tumors ,Mucin-1 ,S100 Proteins ,General Medicine ,Middle Aged ,medicine.disease ,Immunohistochemistry ,Magnetic Resonance Imaging ,Radiation therapy ,Spindle cell oncocytoma ,Treatment Outcome ,Neurology ,biology.protein ,Female ,Radiotherapy, Adjuvant ,Neurology (clinical) ,Neoplasm Recurrence, Local ,Adjuvant - Abstract
Spindle cell oncocytoma (SCO) of the adenohypophysis is a recently defined pituitary tumor mimicking a non-functioning macroadenoma and composed of mitochondrion rich tumor cells, positive for S-100, vimentin, epithelial membrane antigen and galectin-3 but lacking cytokeratins, pituitary hormones, and neuroendocrine markers. Derivation from pituitary folliculostellate cells (FSCs) has been suggested based upon immunohistochemical and ultrastructural characteristics shared by SCO and FSCs. 10 cases of SCO have been reported to date; of these, 8 underwent a benign clinical course and 2 recurred. We report a case of SCO with typical histologic and immunohistochemical features in addition to marked cellular pleomorphism and nuclear atypia. It showed slow regrowth over a 30-month period of follow-up despite combined surgical and radiotherapy. Despite the benign course of most reported cases, additional experience with longer follow-up are needed to assess clinical, histopathologic, and proliferative indices and their relevance to optimal therapy for this rare pituitary tumor.
- Published
- 2009
47. Automatic vessel removal in gliomas from dynamic susceptibility contrast imaging
- Author
-
Atle Bjørnerud, John K. Hald, Paulina Due-Tønnessen, and Kyrre E. Emblem
- Subjects
Adult ,Male ,Vessel segmentation ,Contrast imaging ,Sensitivity and Specificity ,Pattern Recognition, Automated ,Young Adult ,Text mining ,Artificial Intelligence ,Histogram ,Glioma ,Image Interpretation, Computer-Assisted ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Segmentation ,Aged ,business.industry ,Brain Neoplasms ,Reproducibility of Results ,Middle Aged ,medicine.disease ,Image Enhancement ,Magnetic Resonance Imaging ,nervous system diseases ,Glioma grading ,cardiovascular system ,Female ,business ,Nuclear medicine ,Algorithms ,Dynamic susceptibility - Abstract
The presence of macroscopic vessels within the tumor region is a potential confounding factor in MR-based dynamic susceptibility contrast (DSC)-enhanced glioma grading. In order to distinguish between such vessels and the elevated cerebral blood volume (CBV) of brain tumors, we propose a vessel segmentation technique based on clustering of multiple parameters derived from the dynamic contrast-enhanced first-pass curve. A total of 77 adult patients with histologically-confirmed gliomas were imaged at 1.5T and glioma regions-of-interest (ROIs) were derived from the conventional MR images by a neuroradiologist. The diagnostic accuracy of applying vessel exclusion by segmentation of glioma ROIs with vessels included was assessed using a histogram analysis method and compared to glioma ROIs with vessels included. For all measures of diagnostic efficacy investigated, the highest values were observed when the glioma diagnosis was based on vessel segmentation in combination with an initial mean transit time (MTT) mask. Our results suggest that vessel segmentation based on DSC parameters may improve the diagnostic efficacy of glioma grading. The proposed vessel segmentation is attractive because it provides a mask that covers all pixels affected by the intravascular susceptibility effect. Magn Reson Med, 2009. © 2009 Wiley-Liss, Inc.
- Published
- 2009
48. Coronal MR Imaging of the Normal 3rd, 4th, and 5th Lumbar and 1st Sacral Nerve Roots
- Author
-
B. E. Hauglum, John K. Hald, and P. H. Nakstad
- Subjects
Nerve root ,Radiological and Ultrasound Technology ,business.industry ,Anatomy ,General Medicine ,Mr imaging ,Lumbar ,Coronal plane ,Healthy volunteers ,Sacral nerve ,Medicine ,Radiology, Nuclear Medicine and imaging ,Lumbar lordosis ,business ,Failed back surgery - Abstract
Seven healthy volunteers underwent coronal MR imaging at 1.5 tesla of the normal 3rd, 4th, and 5th lumbar, and 1st sacral nerve roots. Coronal slices, 3-mm-thick with a 0.3-mm gap between the slices were obtained (TR/TE 600/22) through the lumbar spinal canal. All the nerve roots were visible on at least one image. One can routinely expect to demonstrate the 3rd, 4th, and 5th lumbar, and 1st sacral nerve roots on T1-weighted, 3-mm-thick coronal MR scans. We found no correlation between the degree of lumbar lordosis and the lengths of the visible nerve roots. Five patients with one of the following spinal problems: anomaly, tumor, disk herniation, and failed back surgery syndrome were examined according to our protocol. In all these cases coronal MR imaging gave the correct diagnosis.
- Published
- 1991
49. Predictive modeling in glioma grading from MR perfusion images using support vector machines
- Author
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Kyrre E. Emblem, Atle Bjørnerud, David Scheie, Bjørn Tennøe, Paulina Due-Tønnessen, Terje Nome, John K. Hald, Baard Nedregaard, and Frank G. Zoellner
- Subjects
Adult ,Adolescent ,Computer science ,information science ,Sensitivity and Specificity ,Pattern Recognition, Automated ,Young Adult ,Text mining ,Artificial Intelligence ,Histogram ,Glioma ,Image Interpretation, Computer-Assisted ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Computer vision ,Child ,Aged ,Mr perfusion ,business.industry ,Brain Neoplasms ,Reproducibility of Results ,Middle Aged ,medicine.disease ,Image Enhancement ,Magnetic Resonance Imaging ,Support vector machine ,Glioma grading ,Sample size determination ,Female ,Artificial intelligence ,business ,Nuclear medicine ,Algorithms ,Dynamic susceptibility - Abstract
The advantages of predictive modeling in glioma grading from MR perfusion images have not yet been explored. The aim of the current study was to implement a predictive model based on support vector machines (SVM) for glioma grading using tumor blood volume histogram signatures derived from MR perfusion images and to assess the diagnostic accuracy of the model and the sensitivity to sample size. A total of 86 patients with histologically-confirmed gliomas were imaged using dynamic susceptibility contrast (DSC) MRI at 1.5T. Histogram signatures from 53 of the 86 patients were analyzed independently by four neuroradiologists and used as a basis for the predictive SVM model. The resulting SVM model was tested on the remaining 33 patients and analyzed by a fifth neuroradiologist. At optimal SVM parameters, the true positive rate (TPR) and true negative rate (TNR) of the SVM model on the 33 patients was 0.76 and 0.82, respectively. The interobserver agreement and the TPR increased significantly when the SVM model was based on an increasing sample size (P < 0.001). This result suggests that a predictive SVM model can aid in the diagnosis of glioma grade from MR perfusion images and that the model improves with increasing sample size. Magn Reson Med 60:945–952, 2008. © 2008 Wiley-Liss, Inc.
- Published
- 2008
50. Preoperative octreotide treatment in newly diagnosed acromegalic patients with macroadenomas increases cure short-term postoperative rates: a prospective, randomized trial
- Author
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Stine Lyngvi Fougner, Thomas Schreiner, Sylvi Aanderud, Jens Bollerslev, Morten Lund-Johansen, Johan Svartberg, John G. Cooper, Øivind Johannesen, John K. Hald, and Sven M. Carlsen
- Subjects
Adult ,Male ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Clinical Biochemistry ,Octreotide ,Context (language use) ,Pituitary neoplasm ,Biochemistry ,law.invention ,Endocrinology ,Postoperative Complications ,Randomized controlled trial ,law ,Internal medicine ,Acromegaly ,medicine ,Humans ,Pituitary Neoplasms ,Prospective Studies ,Insulin-Like Growth Factor I ,Prospective cohort study ,Aged ,Transsphenoidal surgery ,business.industry ,Biochemistry (medical) ,Glucose Tolerance Test ,Middle Aged ,medicine.disease ,Combined Modality Therapy ,Magnetic Resonance Imaging ,Surgery ,Clinical trial ,Female ,business ,medicine.drug - Abstract
Surgery is the primary treatment of acromegaly. However, it often fails to cure the patient. New strategies that improve surgical outcome are needed.Our objective was to investigate whether 6-month preoperative treatment with octreotide improves the surgical outcome in newly diagnosed acromegalic patients.During a 5-yr period (1999-2004), all newly diagnosed acromegalic patients between 18 and 80 yr of age in Norway were screened and invited to participate in the study. A total of 62 patients was included in the Preoperative Octreotide Treatment of Acromegaly study.After a baseline evaluation, patients were randomized directly to transsphenoidal surgery (n = 30) or pretreatment with octreotide (n = 32) 20 mg im every 28th day for 6 months before transsphenoidal surgery. Cure was evaluated 3 months postoperatively primarily by IGF-I levels.According to the IGF-I criteria, 14 of 31 (45%) pretreated patients vs. seven of 30 (23%) patients with direct surgery were cured by surgery (P = 0.11). In patients with microadenomas (or = 10 mm), one of five (20%) pretreated vs. three of five (60%) with direct surgery were cured (P = 0.52). In patients with macroadenomas, 13 of 26 (50%) pretreated vs. four of 25 (16%) with direct surgery were cured (P = 0.017).Six-month preoperative octreotide treatment might improve surgical cure rate in newly diagnosed acromegalic patients with macroadenomas. These results have to be confirmed in future studies.
- Published
- 2008
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