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Objective: The present study aimed to investigate the association between pituitary adenoma (PA) consistency and other measurable tumor characteristics, extent of resection (EOR), postoperative complications, and outcomes., Methods: In total, 507 PA resections were intraoperatively assigned a consistency grade from 1 (cystic/hemorrhagic tumors) to 5 (calcified tumors) based on intraoperative tumor characteristics. Tumor consistency was analyzed in tertiles (grades 1 and 2, grade 3, and grades 4 and 5) to determine associations with tumor characteristics, EOR, recurrence, postoperative outcomes, and complications., Results: The cohort in this study included primarily macroadenomas (93.3%) comprised mostly of nonfunctional PAs (NFPAs) (79.5%), with 77.1% showing suprasellar extension, 16.6% showing infrasellar invasion, and 46.4% showing cavernous sinus invasion (CSI). PA consistency grades were as follows: grade 1 or 2 (40.6%), grade 3 (39.3%), and grade 4 or 5 (20.1%). Compared with grade 1 or 2, higher-consistency PAs were more common in men (p = 0.001) and trended toward lower rates of gross-total resection (GTR) (67.6% vs 53.5%, p = 0.06). Higher PA consistency was predictive of any postoperative complication (OR 1.23, 95% CI 1.05-1.43; p = 0.009), specifically including transient diabetes insipidus (DI) (OR 1.45, 95% CI 1.12-1.85; p = 0.004) and cranial nerve (CN) paresis (OR 3.45, 95% CI 1.56-7.69; p = 0.002). Higher consistency was a strong predictor of CN palsy (OR 3.33, 95% CI 1.52-7.30; p = 0.004) for NFPAs. Higher-consistency PAs were more frequently adrenocorticotropic hormone-positive in both univariable (OR 1.33, 95% CI 1.11-1.60; p = 0.002) and multivariable (OR 1.38, 95% CI 1.11-1.69; p = 0.004) analyses. Higher consistency was associated with lower rates of GTR on stratification by CSI for Knosp grade 3 (p < 0.001) and grade 4 (p < 0.001) PAs, but not in low-grade (Knosp grades 1 and 2) PAs., Conclusions: Tumor consistency is an important consideration for the resection strategy, particularly for PAs with CSI, and a predictor of intraoperative CSF leaks and perioperative complications and outcomes, including EOR, CN paresis, and transient DI.

Objective: Tumor consistency, or fibrosity, affects the ability to optimally resect meningiomas, especially with recent trends evolving toward minimally invasive approaches. The authors' team previously validated a practical 5-point scale for intraoperative grading of meningioma consistency. The impact of meningioma consistency on surgical management and outcomes, however, has yet to be explored. This study aimed to determine associations between meningioma consistency and presenting symptoms, tumor characteristics, and postoperative outcomes., Methods: A total of 209 surgically resected meningiomas were intraoperatively assigned a consistency grade according to a previously validated 5-point scale, ranging from extremely soft, suctionable tumors (grade 1) to firm/calcified tumors (grade 5). Presenting symptoms, tumor characteristics, postoperative complications, and surgical outcomes for these patients were prospectively collected. Tumor consistency was analyzed in three categories (grades 1 and 2, grade 3, and grades 4 and 5), using ANOVA, chi-square or Fisher's exact tests, and univariable logistic regression to evaluate associations between consistency and perioperative characteristics., Results: The study cohort included 209 patients, of whom 48 (23%) were males with a mean age of 55.0 ± 13.7 years. Meningioma consistency distribution was as follows: grades 1 and 2 (n = 23, 11.0%), grade 3 (n = 88, 42.1%), and grades 4 and 5 (n = 98, 46.9%). The majority of meningiomas were skull base tumors (n = 144, 68.9%). Higher-consistency tumors were associated with lower rates of gross-total resection (OR 0.24, 95% CI 0.13-0.46; p < 0.001), increased invasiveness (OR 4.73, 95% CI 1.53-14.60; p = 0.007), tumor recurrence following resection (OR 3.30, 95% CI 1.25-8.66; p = 0.016), reoperation (OR 3.08, 95% CI 1.16-8.14; p = 0.024), and increased complication rates (OR 2.08, 95% CI 1.05-4.15; p = 0.037). No significant associations were identified with preoperative symptoms, tumor size (mean 4.04 ± 1.50 cm), or duration of surgery (mean 4.26 ± 1.60 hours) (all p > 0.05)., Conclusions: Tumor consistency is associated with important meningioma characteristics and perioperative outcomes. A prior knowledge pertaining to meningioma consistency and tumor characteristics using advanced imaging is a priority and may provide surgeons with meaningful data to guide resection strategy and anticipate postoperative outcomes and complications.

The translation of AI-generated brain metastases (BM) segmentation into clinical practice relies heavily on diverse, high-quality annotated medical imaging datasets. The BraTS-METS 2023 challenge has gained momentum for testing and benchmarking algorithms using rigorously annotated internationally compiled real-world datasets. This study presents the results of the segmentation challenge and characterizes the challenging cases that impacted the performance of the winning algorithms. Untreated brain metastases on standard anatomic MRI sequences (T1, T2, FLAIR, T1PG) from eight contributed international datasets were annotated in stepwise method: published UNET algorithms, student, neuroradiologist, final approver neuroradiologist. Segmentations were ranked based on lesion-wise Dice and Hausdorff distance (HD95) scores. False positives (FP) and false negatives (FN) were rigorously penalized, receiving a score of 0 for Dice and a fixed penalty of 374 for HD95. The mean scores for the teams were calculated. Eight datasets comprising 1303 studies were annotated, with 402 studies (3076 lesions) released on Synapse as publicly available datasets to challenge competitors. Additionally, 31 studies (139 lesions) were held out for validation, and 59 studies (218 lesions) were used for testing. Segmentation accuracy was measured as rank across subjects, with the winning team achieving a LesionWise mean score of 7.9. The Dice score for the winning team was 0.65 ± 0.25. Common errors among the leading teams included false negatives for small lesions and misregistration of masks in space. The Dice scores and lesion detection rates of all algorithms diminished with decreasing tumor size, particularly for tumors smaller than 100 mm3. In conclusion, algorithms for BM segmentation require further refinement to balance high sensitivity in lesion detection with the minimization of false positives and negatives. The BraTS-METS 2023 challenge successfully curated well-annotated, diverse datasets and identified common errors, facilitating the translation of BM segmentation across varied clinical environments and providing personalized volumetric reports to patients undergoing BM treatment., Competing Interests: Conflicts of Interest No conflicts of interest to disclose.

Radiographic assessment plays a crucial role in the management of patients with central nervous system (CNS) tumors, aiding in treatment planning and evaluation of therapeutic efficacy by quantifying response. Recently, an updated version of the Response Assessment in Neuro-Oncology (RANO) criteria (RANO 2.0) was developed to improve upon prior criteria and provide an updated, standardized framework for assessing treatment response in clinical trials for gliomas in adults. This article provides an overview of significant updates to the criteria including (1) the use of a unified set of criteria for high and low grade gliomas in adults; (2) the use of the post-radiotherapy MRI scan as the baseline for evaluation in newly diagnosed high-grade gliomas; (3) the option for the trial to mandate a confirmation scan to more reliably distinguish pseudoprogression from tumor progression; (4) the option of using volumetric tumor measurements; and (5) the removal of subjective non-enhancing tumor evaluations in predominantly enhancing gliomas (except for specific therapeutic modalities). Step-by-step pragmatic guidance is hereby provided for the neuroradiologist and imaging core lab involved in operationalization and technical execution of RANO 2.0 in clinical trials, including the display of representative cases and in-depth discussion of challenging scenarios., (© 2024 by American Journal of Neuroradiology.)

Purpose: To develop and validate a 3D turbo spin-echo (TSE)-compatible approach to enhancing black-blood (BB) effects while preserving T 1 weighting and overall SNR., Methods: Following the excitation RF pulse, a 180° RF pulse sandwiched by a pair of flow-sensitive dephasing (FSD) gradient pulses in the phase- (y) and partition-encoding (z) directions, respectively, is added. The polarity of FSD gradients in z direction is toggled every TR, achieving an interleaved FSD (iFSD) configuration in y-z plane. The technique was optimized and evaluated in 18 healthy volunteers and 32 patients with neurovascular disease or brain metastases. Comparisons were made among TSE with and without one of BB preparations: iFSD, delay alternating with nutation for tailored excitation, and motion-sensitized driven equilibrium., Results: iFSD-TSE achieved the best blood flow suppression indicated by venous sinus SNR and parenchyma-to-sinus contrast-to-noise ratio (CNR). iFSD-TSE yielded slightly lower white matter SNR (106.6 ± 32.9) and white-to-gray matter CNR (27.3 ± 8.1) compared to TSE (111.4 ± 31.5 and 28.6 ± 8.8), which were significantly higher than those of delay alternating with nutation for tailored excitation-prepared TSE (84.3 ± 25.0 and 16.8 ± 4.8) and motion-sensitized driven equilibrium-prepared TSE (77.3 ± 26.6 and 15.9 ± 5.3). At the neurovascular wall lesions, iFSD-TSE yielded the highest wall-to-lumen CNR among the three sequences with a BB preparation, all of which significantly outperformed TSE. iFSD-TSE effectively suppressed slow-flow artifacts that otherwise mimicked an atherosclerotic lesion or strongly contrast-enhancing vessel wall. In diagnosing brain metastases, iFSD allowed for highest inter-reader agreement (κ 0.75) and shortest reading time., Conclusion: iFSD is a promising approach compatible with 3D TSE for robust blood flow suppression and preserved T 1 weighting and overall SNR., (© 2024 The Author(s). Magnetic Resonance in Medicine published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.)

The dynamic susceptibility contrast (DSC) MRI measures of relative cerebral blood volume (rCBV) play a central role in monitoring therapeutic response and disease progression in patients with gliomas. Previous investigations have demonstrated promise of using rCBV in classifying tumor grade, elucidating tumor viability after therapy, and differentiating pseudoprogression and pseudoresponse. However, the quantification and reproducibility of rCBV measurements across patients, devices, and software remain a critical barrier to routine or clinical trial use of longitudinal DSC MRI in patients with gliomas. To address this limitation, the RSNA DSC MRI Biomarker Committee of the Quantitative Imaging Biomarkers Alliance developed a Profile that defines statistics-based claims for the precision of longitudinal measurements. Although rCBV is the clinical marker of interest, the Profile focused on the reproducibility of the measured quantitative imaging biomarker, which is the area under the contrast agent concentration-time curve (AUC) normalized by the mean value of normal-appearing contralateral white matter tissue (tissue-normalized AUC values). Based on previous reports of within-subject coefficient of variation (wCV) in the tissue-normalized AUC values for enhancing gliomas (wCV = 0.31), an increase of 182% or more with respect to the baseline tissue-normalized AUC value indicates that an increase has occurred with 95% confidence. In contrast, a decrease of 64% or more with respect to baseline suggests that a decrease has occurred with 95% confidence. Similarly, an increase of 399% or more in the tissue-normalized AUC values in normal brain gray matter tissue (wCV = 0.40) suggests that an increase has occurred with 95% confidence, whereas a decrease of 80% or more with respect to baseline suggests that a decrease has occurred with 95% confidence. This article provides the rationale for these claims and the compliance activities needed to achieve these claims. Potential updates to incorporate new data based on advances in technology and clinical care in the Profile are also discussed., (© RSNA, 2024 See also the editorial by Peters in this issue.)

All T1-weighted images are built upon one of two fundamental pulse sequences, spin-echo and gradient echo, each of which has distinct signal characteristics and clinical applications. Moreover, within each broadly defined category of T1-weighting, acquisition parameters can be modified to affect image quality, contrast, and scan duration; each tailored sequence has unique advantages, drawbacks, clinical indications, and potential artifacts. In this review, we describe key features that distinguish different types of T1-weighted sequences and discuss the utility of each sequence for specific clinical settings, including neuro-oncology, vasculopathy, and pediatric neuroradiology. In addition, we provide case examples from our institution that illustrate common artifacts and pitfalls associated with image interpretation. The findings described herein provide a framework to individualize the imaging protocol based on patient presentation and clinical indication., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.)

Background and Purpose: A national consensus recommendation for the collection of DSC (dynamic susceptibility contrast) MRI perfusion data, used to create maps of relative cerebral blood volume (rCBV), has been recently established for primary and metastatic brain tumors. The goal was to reduce inter-site variability and improve ease of comparison across time and sites, fostering widespread use of this informative measure. To translate this goal into practice the prospective collection of consensus DSC-MRI data and characterization of derived rCBV maps in brain metastases is needed. The purpose of this multi-site study was to determine rCBV in untreated brain metastases in comparison to glioblastoma and normal appearing brain using the national consensus protocol., Materials and Methods: Subjects from three sites with untreated enhancing brain metastases underwent DSC-MRI according to a recommended option that uses a mid-range flip angle, GRE-EPI acquisition and the administration of both a pre-load and 2 nd DSC-MRI dose of 0.1 mmol/kg GBCA. Quantitative maps of standardized rCBV (sRCBV) were generated and enhancing lesion ROIs determined from post-contrast T1-weighted images alone or calibrated difference maps, termed delta T1 (dT1) maps. Mean sRCBV for metastases were compared to normal appearing white matter (NAWM) and glioblastoma (GBM) from a previous study. Comparisons were performed using either the Wilcoxon signed-rank test for paired comparisons or the Mann-Whitney nonparametric test for unpaired comparisons., Results: 49 patients with a primary histology of lung (n=25), breast (n=6), squamous cell carcinoma (SCC) (n=1), melanoma (n=5), gastrointestinal (GI) (n=3) and genitourinary (GU) (n=9) were included in comparison to GBM (n=31). The mean sRCBV of all metastases (1.83+/-1.05) were significantly lower (p=0.0009) than mean sRCBV for GBM (2.67±1.34) with both statistically greater (p<0.0001) than NAWM (0.68 +/- 0.18). Histologically distinct metastases are each statistically greater than NAWM (p<0.0001) with lung (p=0.0002) and GU (p=.02) sRCBV being significantly different than GBM sRCBV., Conclusions: 49 patients with a primary histology of lung (n=25), breast (n=6), squamous cell carcinoma (SCC) (n=1), melanoma (n=5), gastrointestinal (GI) (n=3) and genitourinary (GU) (n=9) were included in comparison to GBM (n=31). The mean sRCBV of all metastases (1.83+/-1.05) were significantly lower (p=0.0009) than mean sRCBV for GBM (2.67+1.34) with both statistically greater (p<0.0001) than NAWM (0.68 +/- 0.18). Histologically distinct metastases are each statistically greater than NAWM (p<0.0001) with lung (p=0.0002) and GU (p=.02) sRCBV being significantly different than GBM sRCBV., Abbreviations: dT1=delta T1; GBCA=gadolinium-based contrast agent; NAWM=normal appearing white matter; normalized relative cerebral blood volume=nRCBV; relative cerebral blood volume=rCBV; standardized relative cerebral blood volume=sRCBV., Competing Interests: Precision Oncology Insights (co-founder L.S.H.); Imaging Biometrics LLC (medical advisory board L.S.H., financial interest (L.S.H., K.M.S.); IQ-AI Ltd. (ownership interest (L.S.H., K.M.S.)); Prism Clinical Imaging (ownership interest K.M.S., board membership K.M.S.). The remaining authors have no conflicts of interest to disclose., (© 2024 by American Journal of Neuroradiology.)

Objective. We aim to develop a Multi-modal Fusion and Feature Enhancement U-Net (MFFE U-Net) coupling with stem cell niche proximity estimation to improve voxel-wise Glioblastoma (GBM) recurrence prediction. Approach. 57 patients with pre- and post-surgery magnetic resonance (MR) scans were retrospectively solicited from 4 databases. Post-surgery MR scans included two months before the clinical diagnosis of recurrence and the day of the radiologicaly confirmed recurrence. The recurrences were manually annotated on the T1ce. The high-risk recurrence region was first determined. Then, a sparse multi-modal feature fusion U-Net was developed. The 50 patients from 3 databases were divided into 70% training, 10% validation, and 20% testing. 7 patients from the 4th institution were used as external testing with transfer learning. Model performance was evaluated by recall, precision, F1-score, and Hausdorff Distance at the 95% percentile (HD95). The proposed MFFE U-Net was compared to the support vector machine (SVM) model and two state-of-the-art neural networks. An ablation study was performed. Main results. The MFFE U-Net achieved a precision of 0.79 ± 0.08, a recall of 0.85 ± 0.11, and an F1-score of 0.82 ± 0.09. Statistically significant improvement was observed when comparing MFFE U-Net with proximity estimation couple SVM (SVM PE ), mU-Net, and Deeplabv3. The HD95 was 2.75 ± 0.44 mm and 3.91 ± 0.83 mm for the 10 patients used in the model construction and 7 patients used for external testing, respectively. The ablation test showed that all five MR sequences contributed to the performance of the final model, with T1ce contributing the most. Convergence analysis, time efficiency analysis, and visualization of the intermediate results further discovered the characteristics of the proposed method. Significance . We present an advanced MFFE learning framework, MFFE U-Net, for effective voxel-wise GBM recurrence prediction. MFFE U-Net performs significantly better than the state-of-the-art networks and can potentially guide early RT intervention of the disease recurrence., (© 2024 Institute of Physics and Engineering in Medicine.)

Compartment models are widely used to quantify blood flow and transport in dynamic contrast-enhanced magnetic resonance imaging. These models analyze the time course of the contrast agent concentration, providing diagnostic and prognostic value for many biological systems. Thus, ensuring accuracy and repeatability of the model parameter estimation is a fundamental concern. In this work, we analyze the structural and practical identifiability of a class of nested compartment models pervasively used in analysis of MRI data. We combine artificial and real data to study the role of noise in model parameter estimation. We observe that although all the models are structurally identifiable, practical identifiability strongly depends on the data characteristics. We analyze the impact of increasing data noise on parameter identifiability and show how the latter can be recovered with increased data quality. To complete the analysis, we show that the results do not depend on specific tissue characteristics or the type of enhancement patterns of contrast agent signal.

Background: Dynamic contrast-enhanced MRI (DCE-MRI) parameters have been shown to be biomarkers for treatment response in glioblastoma (GBM). However, variations in analysis and measurement methodology complicate determination of biological changes measured via DCE. The aim of this study is to quantify DCE-MRI variations attributable to analysis methodology and image quality in GBM patients., Methods: The Extended Tofts model (eTM) and Leaky Tracer Kinetic Model (LTKM), with manually and automatically segmented vascular input functions (VIFs), were used to calculate perfusion kinetic parameters from 29 GBM patients with double-baseline DCE-MRI data. DCE-MRI images were acquired 2-5 days apart with no change in treatment. Repeatability of kinetic parameters was quantified with Bland-Altman and percent repeatability coefficient (%RC) analysis., Results: The perfusion parameter with the least RC was the plasma volume fraction ( v p ), with a %RC of 53%. The extra-cellular extra-vascular volume fraction ( v e ) %RC was 82% and 81%, for extended Tofts-Kety Model (eTM) and LTKM respectively. The %RC of the volume transfer rate constant ( K trans ) was 72% for the eTM, and 82% for the LTKM, respectively. Using an automatic VIF resulted in smaller %RCs for all model parameters, as compared to manual VIF., Conclusions: As much as 72% change in K trans (eTM, autoVIF) can be attributable to non-biological changes in the 2-5 days between double-baseline imaging. Poor K trans repeatability may result from inferior temporal resolution and short image acquisition time. This variation suggests DCE-MRI repeatability studies should be performed institutionally, using an automatic VIF method and following quantitative imaging biomarkers alliance guidelines., (© The Author(s) 2021. Published by Oxford University Press, the Society for Neuro-Oncology and the European Association of Neuro-Oncology.)

Objective: Aneurysmal subarachnoid hemorrhage (aSAH)-induced vasospasm is linked to increased inflammatory cell trafficking across a permeable blood-brain barrier (BBB). Elevations in serum levels of matrix metalloprotease 9 (MMP9), a BBB structural protein, have been implicated in the pathogenesis of vasospasm onset. Minocycline is a potent inhibitor of MMP9. The authors sought to detect an effect of minocycline on BBB permeability following aSAH., Methods: Patients presenting within 24 hours of symptom onset with imaging confirmed aSAH (Fisher grade 3 or 4) were randomized to high-dose (10 mg/kg) minocycline or placebo. The primary outcome of interest was BBB permeability as quantitated by contrast signal intensity ratios in vascular regions of interest on postbleed day (PBD) 5 magnetic resonance permeability imaging. Secondary outcomes included serum MMP9 levels and radiographic and clinical evidence of vasospasm., Results: A total of 11 patients were randomized to minocycline (n = 6) or control (n = 5) groups. No adverse events or complications attributable to minocycline were reported. High-dose minocycline administration was associated with significantly lower permeability indices on imaging analysis (p < 0.01). There was no significant difference with respect to serum MMP9 levels between groups, although concentrations trended upward in both cohorts. Radiographic vasospasm was noted in 6 patients (minocycline = 3, control = 3), with only 1 patient developing symptoms of clinical vasospasm in the minocycline cohort. There was no difference between cohorts with respect to Lindegaard ratios, transcranial Doppler values, or onset of vasospasm., Conclusions: Minocycline at high doses is well tolerated in the ruptured cerebral aneurysm population. Minocycline curtails breakdown of the BBB following aSAH as evidenced by lower permeability indices, though minocycline did not significantly alter serum MMP9 levels. Larger randomized clinical trials are needed to assess minocycline as a neuroprotectant against aSAH-induced vasospasm. Clinical trial registration no.: NCT04876638 (clinicaltrials.gov).

Up to two-thirds of stroke survivors experience persistent sensorimotor impairments. Recovery relies on the integrity of spared brain areas to compensate for damaged tissue. Deep grey matter structures play a critical role in the control and regulation of sensorimotor circuits. The goal of this work is to identify associations between volumes of spared subcortical nuclei and sensorimotor behaviour at different timepoints after stroke. We pooled high-resolution T 1 -weighted MRI brain scans and behavioural data in 828 individuals with unilateral stroke from 28 cohorts worldwide. Cross-sectional analyses using linear mixed-effects models related post-stroke sensorimotor behaviour to non-lesioned subcortical volumes (Bonferroni-corrected, P  < 0.004). We tested subacute (≤90 days) and chronic (≥180 days) stroke subgroups separately, with exploratory analyses in early stroke (≤21 days) and across all time. Sub-analyses in chronic stroke were also performed based on class of sensorimotor deficits (impairment, activity limitations) and side of lesioned hemisphere. Worse sensorimotor behaviour was associated with a smaller ipsilesional thalamic volume in both early ( n  = 179; d  =   0.68) and subacute ( n  = 274, d  =   0.46) stroke. In chronic stroke ( n  = 404), worse sensorimotor behaviour was associated with smaller ipsilesional putamen ( d  =   0.52) and nucleus accumbens ( d  =   0.39) volumes, and a larger ipsilesional lateral ventricle ( d  =   -0.42). Worse chronic sensorimotor impairment specifically (measured by the Fugl-Meyer Assessment; n  = 256) was associated with smaller ipsilesional putamen ( d  =   0.72) and larger lateral ventricle ( d  = -0.41) volumes, while several measures of activity limitations ( n  = 116) showed no significant relationships. In the full cohort across all time ( n  = 828), sensorimotor behaviour was associated with the volumes of the ipsilesional nucleus accumbens ( d  =   0.23), putamen ( d  =   0.33), thalamus ( d  =   0.33) and lateral ventricle ( d  = -0.23). We demonstrate significant relationships between post-stroke sensorimotor behaviour and reduced volumes of deep grey matter structures that were spared by stroke, which differ by time and class of sensorimotor measure. These findings provide additional insight into how different cortico-thalamo-striatal circuits support post-stroke sensorimotor outcomes., (© The Author(s) (2021). Published by Oxford University Press on behalf of the Guarantors of Brain.)

Objective: Given the anatomical complexity and frequently invasive growth of giant pituitary adenomas (GPAs), individually tailored approaches are required. The aim of this study was to assess the treatment strategies and outcomes in a large multicenter series of GPAs in the era of endoscopic transsphenoidal surgery (ETS)., Methods: This was a retrospective case-control series of 64 patients with GPAs treated at two tertiary care centers by surgeons with experience in ETS. GPAs were defined by a maximum diameter of ≥ 4 cm and a volume of ≥ 10 cm3 on preoperative isovoxel contrast-enhanced MRI., Results: The primary operation was ETS in all cases. Overall gross-total resection rates were 64% in round GPAs, 46% in dumbbell-shaped GPAs, and 8% in multilobular GPAs (p < 0.001). Postoperative outcomes were further stratified into two groups based on extent of resection: group A (gross-total resection or partial resection with intracavernous remnant; 21/64, 33%) and group B (partial resection with intracranial remnant; 43/64, 67%). Growth patterns of GPAs were mostly round (11/14, 79%) in group A and multilobular (33/37, 89%) in group B. In group A, no patients required a second operation, and 2/21 (9%) were treated with adjuvant radiosurgery. In group B, early transcranial reoperation was required in 6/43 (14%) cases due to hemorrhagic transformation of remnants. For the remaining group B patients with remnants, 5/43 (12%) underwent transcranial surgery and 12/43 (28%) underwent delayed second ETS. There were no deaths in this series. Severe complications included stroke (6%), meningitis (6%), hydrocephalus requiring shunting (6%), and loss or distinct worsening of vision (3%). At follow-up (mean 3 years, range 0.5-16 years), stable disease was achieved in 91% of cases., Conclusions: ETS as a primary treatment modality to relieve mass effect in GPAs and extent of resection are dependent on GPA morphology. The pattern of residual pituitary adenoma guides further treatment strategies, including early transcranial reoperation, delayed endoscopic transsphenoidal/transcranial reoperation, and adjuvant radiosurgery.

Background: The direct endoscopic endonasal approach (EEA) has become the primary technique used for resection of sellar pathology, meriting investigation into the risk factors for complications and predictors of postoperative outcomes after direct EEA., Methods: We retrospectively analyzed the patient and tumor characteristics from 404 patients who had undergone direct EEA for sellar pathology at the USC Pituitary Center from September 2011 to December 2019., Results: Of the 404 pathologic entities included, 349 (86%) were pituitary adenomas (PAs), 29 (7%) were Rathke cleft cysts, and 26 (6%) were other sellar lesions. The mean lesion diameter was 2.3 cm, with 34 microadenomas (10%) and 315 macroadenomas (90%). Cavernous sinus invasion was present in 39% of the PAs. No patient died. The surgical complications included internal carotid artery injury without neurological sequelae (0.2%), vision loss (0.7%), meningitis (0.7%), cerebrospinal fluid leak (4%), epistaxis (4%), sinusitis (1%), transient cranial nerve paresis (0.5%), and postoperative abscess (0.25%). New hypopituitarism developed in 3%. Gross total resection was achieved in 208 PA cases (58%). Clinical improvement of headaches and visual deficits were reported for 67% and 76% of cases, respectively. Hormonal remission was achieved in 82% of patients with functional PAs. The median hospital stay was 2 days, with 34 patients (8%) readmitted within 30 days and 10 (3%) undergoing early reoperation. Disease recurrence or progression developed in 10% and was less likely in the case of gross total resection and apoplexy., Conclusion: In the present, large, consecutive, mostly single-surgeon series, the patients experienced clinical improvement in most preoperative symptoms and had low rates of perioperative morbidity. We have demonstrated that direct EEA can be efficiently, safely, and successfully performed by a neurosurgical team., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Cushing's disease manifests as symptoms of glucocorticoid excess secondary to the increased secretion of corticotropin by a corticotroph adenoma in the pituitary gland. Unfortunately, magnetic resonance imaging (MRI) performed at conventional clinical field strengths of 1.5 or 3 Tesla has limited sensitivity for the detection of these pituitary tumors, and radiologic uncertainty often necessitates more invasive workup to confirm diagnosis and guide resection. It has been postulated that higher static magnetic field strengths may increase the adenoma detection rate and thus the utility of MRI for this clinical application. In this report, we describe our initial experience using ultra-high field 7 Tesla (7 T) MRI in patients with suspected Cushing's disease and negative or equivocal imaging at conventional field strengths. We performed contrast-enhanced 7 T pituitary MRI in 10 patients with up to three different T1-weighted sequences and correlated the imaging abnormalities identified with results of histologic evaluation in patients who subsequently underwent resection. We found that 7 T MRI enabled the identification of previously undetected areas of focal pituitary hypoenhancement in 9 patients (90%), of which 7 corresponded histologically to corticotroph adenomas. These early findings suggest an important adjunctive role for ultra-high field MR imaging in the noninvasive clinical workup of suspected Cushing's disease.

Objective: Pituitary adenoma (PA) consistency, or texture, is an important intraoperative characteristic that may dictate operative dissection techniques and/or instruments used for tumor removal during endoscopic endonasal approaches (EEAs). The impact of PA consistency on surgical outcomes has yet to be elucidated., Methods: The authors developed an objective 5-point grading scale for PA consistency based on intraoperative characteristics, including ease of tumor debulking, manipulation, and instrument selection, ranging from cystic/hemorrhagic tumors (grade 1) to calcified tumors (grade 5). The proposed grading system was prospectively assessed in 306 consecutive patients who underwent an EEA for PAs, and who were subsequently analyzed for associations with surgical outcomes, including extent of resection (EOR) and complication profiles., Results: Institutional database review identified 306 patients who underwent intraoperative assessment of PA consistency, of which 96% were macroadenomas, 70% had suprasellar extension, and 44% had cavernous sinus invasion (CSI). There were 214 (69.9%) nonfunctional PAs and 92 functional PAs (31.1%). Distribution of scores included 15 grade 1 tumors (4.9%), 112 grade 2 tumors (36.6%), 125 grade 3 tumors (40.8%), 52 grade 4 tumors (17%), and 2 grade 5 tumors (0.7%). Compared to grade 1/2 and grade 3 PAs, grade 4/5 PAs were significantly larger (22.5 vs 26.6 vs 27.4 mm, p < 0.01), more likely to exhibit CSI (39% vs 42% vs 59%, p < 0.05), and trended toward nonfunctionality (67% vs 68% vs 82%, p = 0.086). Although there was no association between PA consistency and preoperative headaches or visual dysfunction, grade 4/5 PAs trended toward preoperative (p = 0.058) and postoperative panhypopituitarism (p = 0.066). Patients with preoperative visual dysfunction experienced greater improvement if they had a grade 1/2 PA (p < 0.05). Intraoperative CSF leaks were noted in 32% of cases and were more common with higher-consistency-grade tumors (p = 0.048), although this difference did not translate to postoperative CSF leaks. Gross-total resection (%) was more likely with lower PA consistency score as follows: grade 1/2 (60%), grade 3 (50%), grade 4/5 (44%; p = 0.045). Extracapsular techniques were almost exclusively performed in grade 4/5 PAs. Assignment of scores showed low variance and high reproducibility, with an intraclass correlation coefficient of 0.905 (95% CI 0.815-0.958), indicating excellent interrater reliability., Conclusions: These findings demonstrate clinical validity of the proposed intraoperative grading scale with respect to PA subtype, neuroimaging features, EOR, and endocrine complications. Future studies will assess the relation of PA consistency to preoperative MRI findings to accurately predict consistency, thereby allowing the surgeon to tailor the exposure and prepare for varying resection strategies.

Background: Rathke cleft cysts (RCCs) are benign sellar and suprasellar lesions commonly presenting as asymptomatic incidental findings. Rarely, RCCs hemorrhage and mimic pituitary apoplexy on presentation., Objective: To review a series of hemorrhagic RCCs for physicians encountering this rare presentation., Methods: A database review of >1700 transsphenoidal pituitary operations was performed at the USC Pituitary Center to identify patients with pathologically confirmed RCCs presenting with acute symptoms and evidence of hemorrhage at the time of surgery. Surgical treatment involved transsphenoidal RCC fenestration and drainage. Clinical, endocrine, and imaging outcomes were reviewed., Results: A total of 119 RCCs were identified, and 6 (5.0%) presented with hemorrhage mimicking pituitary apoplexy. Presenting symptoms included acute onset headaches (5/6), vision loss (2/6), and oculomotor nerve palsy (n = 1). Endocrine disturbances at presentation included pre-existing amenorrhea in all female patients (3/3), hypothyroidism (n = 2), panhypopituitarism (n = 2), and one with profound hyponatremia (Na 116 meq/L). All patients underwent endonasal transsphenoidal fenestration and drainage with no major complications. Over mean follow-up of 38.4 mo, 2/2 patients with vision loss reported improvement, and 2/5 patients with headaches reported improvement. Although all women resumed menses, patients with preoperative hypopituitarism did not experience pituitary axis improvement. Follow-up magnetic resonance imaging showed no instances of RCC recurrence with a mean imaging follow-up of 38.6 mo., Conclusion: RCCs occasionally present with hemorrhage and clinical symptoms that may be confused with apoplexy. Outcomes following hemorrhagic RCC treatment are excellent when treated at tertiary pituitary centers. Although hyperprolactinemia often improves following surgery, other pituitary axis deficits typically do not., (Copyright © 2019 by the Congress of Neurological Surgeons.)

Background: The management of pituitary apoplexy, caused by acute hemorrhage and/or infarction of a pituitary adenoma, is debated., Objective: To analyze clinical characteristics of patients undergoing endoscopic endonasal approaches (EEAs) for pituitary apoplexy., Methods: A retrospective review of patients at our institution from 2012 to 2018 undergoing EEA for pituitary apoplexy diagnosed clinically and with imaging/pathologic findings. Analysis included demographics, symptoms, neuroendocrine deficits, neuroimaging, complications, symptom resolution, and follow-up details., Results: Fifty patients (mean age, 53 years) were included. Preoperative symptoms included headache (86%), vision loss (62%), and cranial nerve paresis (40%). Mean tumor diameter was 2.7 cm and extrasellar extension was observed in 96% of tumors. Twenty-eight tumors were hemorrhagic (76%), 24 were necrotic (65%), and 13 (35%) had both features. Magnetic resonance imaging showed gross total resection in 58% of patients. Headache and vision loss improved in 87% and 86% of presenting patients. Cranial nerve paresis resolved in 72% of patients, partially improved in 11%, and remained unchanged in 17%. There were no deaths or carotid artery injuries. Surgical complications included postoperative cerebrospinal fluid leak (n = 4, 8%), epistaxis (n = 2, 4%), postoperative abscess (n = 1, 2%), and transient postoperative vision loss requiring reoperation (n = 1, 4%). Endocrinopathies improved in 21% of patients and panhypopituitarism persisted in 48% and developed in 6% of patients. Mean follow-up time was 26 months; 2 patients experienced recurrence., Conclusions: EEA for pituitary apoplexy is effective in rapidly improving headache and visual symptoms. Although neuro-ophthalmic deficits often improve over time, panhypopituitarism persists in most patients after surgical resection., (Copyright © 2020. Published by Elsevier Inc.)

This review summarizes the last decade of work by the ENIGMA (Enhancing NeuroImaging Genetics through Meta Analysis) Consortium, a global alliance of over 1400 scientists across 43 countries, studying the human brain in health and disease. Building on large-scale genetic studies that discovered the first robustly replicated genetic loci associated with brain metrics, ENIGMA has diversified into over 50 working groups (WGs), pooling worldwide data and expertise to answer fundamental questions in neuroscience, psychiatry, neurology, and genetics. Most ENIGMA WGs focus on specific psychiatric and neurological conditions, other WGs study normal variation due to sex and gender differences, or development and aging; still other WGs develop methodological pipelines and tools to facilitate harmonized analyses of "big data" (i.e., genetic and epigenetic data, multimodal MRI, and electroencephalography data). These international efforts have yielded the largest neuroimaging studies to date in schizophrenia, bipolar disorder, major depressive disorder, post-traumatic stress disorder, substance use disorders, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, autism spectrum disorders, epilepsy, and 22q11.2 deletion syndrome. More recent ENIGMA WGs have formed to study anxiety disorders, suicidal thoughts and behavior, sleep and insomnia, eating disorders, irritability, brain injury, antisocial personality and conduct disorder, and dissociative identity disorder. Here, we summarize the first decade of ENIGMA's activities and ongoing projects, and describe the successes and challenges encountered along the way. We highlight the advantages of collaborative large-scale coordinated data analyses for testing reproducibility and robustness of findings, offering the opportunity to identify brain systems involved in clinical syndromes across diverse samples and associated genetic, environmental, demographic, cognitive, and psychosocial factors.

Objective: Sociodemographic disparities in health outcomes are well documented, but the effects of such disparities on preoperative presentation of pituitary adenomas (PA) and surgical outcomes following resection are not completely understood. In this study the authors sought to compare the preoperative clinical characteristics and postoperative outcomes in patients undergoing PA resection at a private hospital (PH) versus a safety-net hospital (SNH)., Methods: The authors conducted a retrospective review over a 36-month period of patients with PAs who underwent endoscopic endonasal transsphenoidal surgery performed by the same attending neurosurgeon at either a PH or an SNH at a single academic medical institution., Results: A total of 92 PH patients and 69 SNH patients were included. SNH patients were more likely to be uninsured or have Medicaid (88.4% vs 10.9%, p < 0.0001). A larger percentage of SNH patients were Hispanic (98.7% vs 32.6% p < 0.0001), while PH patients were more likely to be non-Hispanic white (39.1% vs 4.3%, p < 0.0001). SNH patients had a larger mean PA diameter (26.2 vs 22.4 mm, p = 0.0347) and a higher rate of bilateral cavernous sinus invasion (13% vs 4.3%, p = 0.0451). SNH patients were more likely to present with headache (68.1% vs 45.7%, p = 0.0048), vision loss (63.8% vs 35.9%, p < 0.0005), panhypopituitarism (18.8% vs 4.3%, p = 0.0031), and pituitary apoplexy (18.8% vs 7.6%, p = 0.0334). Compared to PH patients, SNH patients were as likely to undergo gross-total resection (73.9% vs 76.1%, p = 0.7499) and had similar rates of postoperative improvement in headache (80% vs 89%, p = 0.14) and vision (82% vs 84%, p = 0.74), but had higher rates of postoperative panhypopituitarism (23% vs 10%, p = 0.04) driven by preoperative endocrinopathies. Although there were no differences in tumor recurrence or progression, loss to follow-up was seen in 7.6% of PH versus 18.6% (p = 0.04) of SNH patients., Conclusions: Patients presenting to the SNH were more often uninsured or on Medicaid and presented with larger, more advanced pituitary tumors. SNH patients were more likely to present with headaches, vision loss, and apoplexy, likely translating to greater improvements in headache and vision observed after surgery. These findings highlight the association between medically underserved populations and more advanced disease states at presentation, and underscore the likely role of academic tertiary multidisciplinary care teams and endoscopic PA resection in somewhat mitigating sociodemographic factors known to portend poorer outcomes, though longer-term follow-up is needed to confirm these findings.

Background: Cystic sellar masses (CSMs) pose diagnostic and therapeutic challenges associated with subtotal cyst wall resection, cerebrospinal fluid (CSF) leak repair, and disease recurrence. Current magnetic resonance imaging (MRI) interpretation often cannot reliably differentiate CSMs, mandating adaptable intraoperative strategies. We reviewed our diagnostic and therapeutic experience after endoscopic endonasal approaches (EEAs) for CSMs., Methods: A retrospective record review of patients with CSM managed via EEA at the University of Southern California from 2011 to 2018 was conducted. Patient demographics, preoperative characteristics, surgical details, pathologic findings, and postoperative outcomes were assessed., Results: Analysis included 47 patients (mean age, 43.2 years); of these, 78.7% were women. Preoperative symptoms included headache (76.6%) and vision loss (42.6%). Histologically verified sellar pathology included 27 Rathke cleft cysts (RCCs) (57.4%), 17 cystic pituitary adenomas (CPAs) (36.2%), 2 arachnoid cysts (4.3%), and 1 xanthogranuloma (2.1%). Twelve patients (70.6%) with CPAs underwent complete resection and 5 (29.4%) underwent subtotal resection. All 27 patients with RCC and 2 patients with arachnoid cyst underwent complete fenestration and drainage. One xanthogranuloma was completely resected. There were 14 intraoperative (29.8%) and 4 postoperative CSF leaks (8.5%). Headaches, vision, and endocrinopathy improved in 69.2%, 80.0%, and 33.3% of patients with CPA and 73.9%, 71.4%, and 40.9% of patients with RCC, respectively. There were 2 RCC recurrences and 1 CPA recurrence over the follow-up period., Conclusions: Surgeons must prepare for versatile management strategies of CSMs based on pretest probability associated with MRI and intraoperative findings. Outcomes after EEA for CSMs show low complication profiles and excellent rates of headache and visual improvement, albeit lower rates of endocrine normalization., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Headaches are exceedingly common, but most individuals who seek medical attention with headache will not have a serious underlying etiology such as a brain tumor. Brain tumors are uncommon; however, many patients with brain tumors do suffer from headaches. Generally these headaches are accompanied by other neurologic signs and symptoms. A careful clinical assessment for red flags should be undertaken when considering further work-up with neuroimaging to exclude a serious underlying condition., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Cushing's disease is caused by adrenocorticotrophic hormone (ACTH)-secreting pituitary adenomas, which are often difficult to identify on standard 1.5-T or 3-T MRI, including dynamic contrast imaging. Inferior petrosal and cavernous sinus sampling remains the gold standard for MRI-negative Cushing's disease.The authors report on a 27-year-old woman with Cushing's disease in whom the results of standard 1.5-T and 3-T MRI, including 1.5-T dynamic contrast imaging, were negative. Inferior petrosal sinus sampling showed a high central-to-peripheral ACTH ratio (148:1) as well as a right-to-left ACTH gradient (19:1), suggesting a right-sided pituitary microadenoma. The patient underwent 7-T MRI, which showed evidence of a right-sided pituitary lesion with focal hypoenhancement not visualized on 1.5-T or 3-T MRI. The patient underwent an endoscopic endonasal transsphenoidal operation, with resection of a right-sided pituitary mass. Postoperatively, she developed clinical symptoms suggestive of adrenal insufficiency and a nadir cortisol level of 1.6 μg/dl on postoperative day 3, and hydrocortisone therapy was initiated. Permanent histopathology specimens showed Crooke's hyaline change and ACTH-positive cells suggestive of an adenoma.MRI at 7 T may be beneficial in identifying pituitary microadenoma location in cases of standard 1.5-T and 3-T MRI-negative Cushing's disease. In the future, 7-T MRI may preempt inferior petrosal sinus sampling and help in cases of standard and dynamic contrast 1.5-T and 3-T MRI-negative Cushing's disease.

Background: Colorectal cancer is the second leading cause of cancer-specific death in the USA. Evidence suggests people with mental illness are less likely to receive preventive health services, including cancer screening. We hypothesized that mental illness is a risk factor for non-adherence to colorectal cancer-screening guidelines., Methods: We analyzed results of the 2007 California Health Interview Survey to test whether mental illness is a risk factor for non-adherence to colorectal cancer-screening recommendations among individuals age 50 or older (N = 15,535). This cross-sectional dataset is representative of California. Screening was defined as either fecal occult blood testing during the preceding year, sigmoidoscopy, or colonoscopy during the preceding 5 years. Mental illness was identified using the Kessler K6 screening tool. Associations were evaluated using weighted multivariate logistic regressions., Results: Mental illness was not associated with colorectal cancer-screening adherence (OR 0.89; 95% CI 0.63-1.25). Risk factors for non-adherence included being female (OR 1.25; 95% CI 1.09-1.44), delaying accessing health care during the previous year (OR 1.89; 95% CI 1.56-2.29)., Conclusion: Unlike previous studies, this study did not find a relationship between mental illness and colorectal cancer-screening adherence. This could be due to differences in study populations. State-specific healthcare policies involving care coordination for individuals with mental illness could also influence colorectal cancer-screening adherence in California.

Dynamic susceptibility contrast (DSC) MR imaging, a perfusion-weighted MR imaging technique typically used in neuro-oncologic applications for estimating the relative cerebral blood volume within brain tumors, has demonstrated much potential for determining prognosis, predicting therapeutic response, and assessing early treatment response of gliomas. This review highlights recent developments using DSC-MR imaging and emphasizes the need for technical standardization and validation in prospective studies in order for this technique to become incorporated into standard-of-care imaging for patients with brain tumors., (Copyright © 2016 Elsevier Inc. All rights reserved.)

This article provides an overview of the neuroimaging literature focused on preoperative prediction of meningioma consistency. A validated, noninvasive neuroimaging method to predict tumor consistency can provide valuable information regarding neurosurgical planning and patient counseling. Most of the neuroimaging literature indicates conventional MRI using T2-weighted imaging may be helpful to predict meningioma consistency; however, further rigorous validation is necessary. Much less is known about advanced MRI techniques, such as diffusion MRI, MR elastography (MRE), and MR spectroscopy. Of these methods, MRE and diffusion tensor imaging appear particularly promising., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Aside from bidimensional measurements from conventional contrast-enhanced MRI, there are no validated or FDA-qualified imaging biomarkers for high-grade gliomas. However, advanced functional MRI techniques, including perfusion- and diffusion-weighted MRI, have demonstrated much potential for determining prognosis, predicting therapeutic response, and assessing early treatment response. They may also prove useful for differentiating pseudoprogression from true progression after temozolomide chemoradiation and pseudoresponse from true response after anti-angiogenic therapy. This review will highlight recent developments using these techniques and emphasize the need for technical standardization and validation in prospective studies in order for these methods to become incorporated into standard-of-care imaging for brain tumor patients., (© The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Although typically not necessary for the diagnosis of intracranial meningiomas, advanced imaging techniques, including perfusion and diffusion imaging, spectroscopy, and nuclear medicine imaging, can help confirm the diagnosis of intracranial meningiomas, especially for meningiomas that do not exhibit the typical anatomic imaging findings. Advanced imaging techniques also have the potential to be able to differentiate between the subtypes of meningiomas, predict clinical aggressiveness of the tumor, and better characterize response to treatment. Although no advanced imaging technique has been able to definitively subclassify meningiomas, current results are encouraging and may be helpful in surgical planning., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Purpose: MRI has been used to identify multiple sclerosis (MS) lesions in brain and spinal cord visually. Integrating patient information into an electronic patient record system has become key for modern patient care in medicine in recent years. Clinically, it is also necessary to track patients' progress in longitudinal studies, in order to provide comprehensive understanding of disease progression and response to treatment. As the amount of required data increases, there exists a need for an efficient systematic solution to store and analyze MS patient data, disease profiles, and disease tracking for both clinical and research purposes., Method: An imaging informatics based system, called MS eFolder, has been developed as an integrated patient record system for data storage and analysis of MS patients. The eFolder system, with a DICOM-based database, includes a module for lesion contouring by radiologists, a MS lesion quantification tool to quantify MS lesion volume in 3D, brain parenchyma fraction analysis, and provide quantitative analysis and tracking of volume changes in longitudinal studies. Patient data, including MR images, have been collected retrospectively at University of Southern California Medical Center (USC) and Los Angeles County Hospital (LAC). The MS eFolder utilizes web-based components, such as browser-based graphical user interface (GUI) and web-based database. The eFolder database stores patient clinical data (demographics, MS disease history, family history, etc.), MR imaging-related data found in DICOM headers, and lesion quantification results. Lesion quantification results are derived from radiologists' contours on brain MRI studies and quantified into 3-dimensional volumes and locations. Quantified results of white matter lesions are integrated into a structured report based on DICOM-SR protocol and templates. The user interface displays patient clinical information, original MR images, and viewing structured reports of quantified results. The GUI also includes a data mining tool to handle unique search queries for MS. System workflow and dataflow steps has been designed based on the IHE post-processing workflow profile, including workflow process tracking, MS lesion contouring and quantification of MR images at a post-processing workstation, and storage of quantitative results as DICOM-SR in DICOM-based storage system. The web-based GUI is designed to display zero-footprint DICOM web-accessible data objects (WADO) and the SR objects., Summary: The MS eFolder system has been designed and developed as an integrated data storage and mining solution in both clinical and research environments, while providing unique features, such as quantitative lesion analysis and disease tracking over a longitudinal study. A comprehensive image and clinical data integrated database provided by MS eFolder provides a platform for treatment assessment, outcomes analysis and decision-support. The proposed system serves as a platform for future quantitative analysis derived automatically from CAD algorithms that can also be integrated within the system for individual disease tracking and future MS-related research. Ultimately the eFolder provides a decision-support infrastructure that can eventually be used as add-on value to the overall electronic medical record., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Introduction: The specific goal of this study was to determine whether the inclusion of MRS had a measureable and positive impact on the accuracy of pre-surgical MR examinations of untreated pediatric brain tumors over that of MRI alone in clinical practice., Methods: Final imaging reports of 120 pediatric patients with newly detected brain tumors who underwent combined MRI/MRS examinations were retrospectively reviewed. Final pathology was available in all cases. Group A comprised 60 subjects studied between June 2001 and January 2005, when MRS was considered exploratory and radiologists utilized only conventional MRI to arrive at a diagnosis. For group B, comprising 60 subjects studied between January 2005 and March 2008, the radiologists utilized information from both MRI and MRS. Furthermore, radiologists revisited group A (blind review, time lapse >4 years) to determine whether the additional information from MRS would have altered their interpretation., Results: Sixty-three percent of patients in group A were diagnosed correctly, whereas in 10% the report was partially correct with the final tumor type mentioned (but not mentioned as most likely tumor), while in 27% of cases the reports were wrong. For group B, the diagnoses were correct in 87%, partially correct in 5%, and incorrect in 8% of the cases, which is a significant improvement (p < 0.005). Re-review of combined MRI and MRS of group A resulted 87% correct, 7% partially correct, and 7% incorrect diagnoses, which is a significant improvement over the original diagnoses (p < 0.05)., Conclusion: Adding MRS to conventional MRI significantly improved diagnostic accuracy in preoperative pediatric patients with untreated brain tumors.

Gliomas comprise 80% of primary brain neoplasms, with glioblastoma multiforme being the most commonly diagnosed glioma. The annual incidence is 5.26 per 100,000, or 17,000 newly diagnosed cases per year in the United States. The incidence increases with age, peaking between the 6th and 8th decades. Gliomas are more common among Caucasians and occur more often in men. They can be associated with certain rare hereditary syndromes including Cowden, Turcot, Li-Fraumeni, neurofibromatosis type 1 and type 2, tuberous sclerosis, and familial schwannomatosis. Known risk factors include a history of ionizing radiation, family history of glioma, and certain genetic susceptibility variants that are weakly associated with glioma. Preventative measures have not been shown to decrease the risk of later development. In addition, screening tests are unwarranted since early diagnosis and treatment have not been shown to improve outcome., (Copyright © 2014. Published by Elsevier Inc.)

Advancements in diffusion-weighted imaging during the past decade have led to the use of diffusion tensor imaging to further characterize the structural integrity of neural tissue and to noninvasively trace neuronal tracts in the brain and spine. This has led to many clinical applications that have aided in surgical planning for brain and spinal cord tumors and has increased the diagnostic potential of magnetic resonance imaging in disorders such as multiple sclerosis, Alzheimer disease, and traumatic brain injury., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Objective: This article addresses questions that radiologists frequently ask when planning, performing, processing, and interpreting MRI perfusion studies in CNS imaging., Conclusion: Perfusion MRI is a promising tool in assessing stroke, brain tumors, and neurodegenerative diseases. Most of the impediments that have limited the use of per-fusion MRI can be overcome to allow integration of these methods into modern neuroimaging protocols.

Although conventional contrast-enhanced MR imaging remains the standard-of-care imaging method in the posttreatment evaluation of gliomas, recent developments in therapeutic options such as chemoradiation and antiangiogenic agents have caused the neuro-oncology community to rethink traditional imaging criteria. This article highlights the latest recommendations. These recommendations should be viewed as works in progress. As more is learned about the pathophysiology of glioma treatment response, quantitative imaging biomarkers will be validated within this context. There will likely be further refinements to glioma response criteria, although the lack of technical standardization in image acquisition, postprocessing, and interpretation also need to be addressed., (Copyright © 2013 Elsevier Inc. All rights reserved.)

This article focuses on advanced magnetic resonance (MR) imaging techniques and how they can be used to help diagnose a specific tumor, suggest tumor grade and prognosis, follow tumor progression, evaluate tumor extension, suggest the ideal site for biopsy, and assess therapeutic response. Advanced MR imaging techniques may also help to distinguish between lesions that simulate brain tumors on conventional MR imaging studies., (Copyright © 2013. Published by Elsevier Inc.)

Objective: This and its companion article address the 10 most frequently asked questions that radiologists face when planning, performing, processing, and interpreting different MR perfusion studies in CNS imaging., Conclusion: Perfusion MRI is a promising tool in assessing stroke, brain tumors, and patients with neurodegenerative diseases. Most of the impediments that have limited the use of perfusion MRI can be overcome to allow integration of these methods into modern neuroimaging protocols.

Neurocysticercosis (NCC) is an infection of the central nervous system by the Taenia solium larvae, and is the most common cause of acquired epilepsy in endemic regions. The natural history of parenchymal NCC lesions can be divided into 4 stages with unique imaging and clinical features. Evaluation of cysticerci is challenging on conventional magnetic resonance (MR) imaging and computed tomography, and is significantly improved with MR cysternography techniques. Differentiation of NCC lesions from metastatic disease and pyogenic abscesses can be improved with advanced MR imaging including (1)H nuclear MR spectroscopy, diffusion-weighted imaging, and MR perfusion imaging., (Copyright © 2012 Elsevier Inc. All rights reserved.)

This article presents an overview of advanced magnetic resonance (MR) imaging techniques using contrast media in neuroimaging, focusing on T2*-weighted dynamic susceptibility contrast MR imaging and T1-weighted dynamic contrast-enhanced MR imaging. Image acquisition and data processing methods and their clinical application in brain tumors, stroke, dementia, and multiple sclerosis are discussed., (Copyright © 2012 Elsevier Inc. All rights reserved.)

One of the major pitfalls faced by physicians is a basic lack of understanding of the legal aspects of medical malpractice. It is the authors' hope that the brief review of the history of malpractice law provided here affords the radiologist insights that could prove helpful in understanding how one must conduct oneself in a radiology practice. There are several noteworthy points to consider. Vigilance and minimizing errors is always most desirable, but error-free neuroradiology is unattainable. Best medical judgment, although not error free, is at least defensible as noted in the case law discussed here., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Objective: The objective of our study was to evaluate the changes in quantitative diffusion tensor (DT) metrics and normalized T2-signal intensity (nT2-SI) values of normal-appearing cortical gray matter (CGM) and deep gray matter (DGM) in patients with multiple sclerosis (MS)., Methods: Fifty patients with MS and 25 patients with no MS matched on sex/age were selected as controls. Conventional magnetic resonance imaging and DT imaging were performed. Fractional anisotropy (FA)/mean diffusivity (MD) and nT2-SI values of CGM and DGM were measured. Analyses of variance between the 2 groups were analyzed; Pearson correlations between DT metrics and nT2-SI values and brain parenchymal fraction (BPF) and T2 lesion volumes (LVs) were used., Results: Patients with MS showed larger MD/smaller FA values in the CGM region compared with controls (P < 0.05). However, MD/FA values were not statistically significant in the DGM between MS and healthy control group. In DGM of MS patients, a significant decrease of nT2-SI values were observed when compared with controls (P < 0.05), but nT2-SI values in the CGM of MS patients showed no significant decrease. In CGM, only MD values of frontal lobes in MS patients were significantly (negatively) correlated with BPF(right: P = 0.009, left: P = 0.036) or T2 LVs (right: P = 0.002, left: P = 0.047). Normalized T2-SI values in all DGM regions of MS patients were significantly correlated with BPF (r = 0.282-0.504, P < 0.05) except for the left thalamus and bilateral red nucleus. There was no correlation between nT2-SI in all DGM regions and T2 LVs of MS patients., Conclusion: In CGM, the change in quantitative DT metrics of MS patients and the association with BPF and T2 LVs suggest the existence of microstructural destruction corresponding to inflammation, demyelination, or wallerian degeneration, but the changes in CGM were independent of the concomitant changes in BPF and T2 lesion. In DGM, a decrease of nT2-SI in MS patients and the correlation of nT2-SI values with BPF (brain atrophy) suggest excessive iron deposition related to chronic destruction. Our investigation indicates the possibility of different mechanism of pathological change in CGM and DGM.