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Purpose of the study. To study the diagnostic informativeness of magnetic resonance imaging (MRI) with the assessment of diffusion- weighted images and the measured diffusion coefficient in the diagnosis of endometrial tumor lesions in polyineoplasias.Materials and methods. The article presents the results of a study of patients with synchronous and metachronous polyneoplasias who were in the AU "Republican clinical oncological dispensary" of the Ministry of health of the Chuvash Republic from 2014 to 2018. All were performed magnetic resonance imaging on Excelart Vantage Atlas (Toshiba, Japan, 1.5 T), ultrasound (Aplio, Xario and Nemio, Toshiba, Japan; Sono Scape, China), x-ray computed tomography on Light Speed VEX Plus and Light Speed RT 16 (GE, USA). All MRI results were compared with morphological data obtained afterhistomorphological examination of the postoperative material. The differences were considered significant at values p≤0.05.Results. 80 cases of endometrial tumor lesions in polyineoplasias (N1a) were detected, which was 44.7% of all cases of the main group (N1; n=179), of which metachronous polyineoplasias were found in 56 (70.0%), synchronous — in 11 (13.7%), combined — in 13 (16.3%) patients. The informative value of MRI in the diagnosis of malignant neoplasms with lesions of the endometrium when multiple neoplasias were: sensitivity of 91.3%, specificity — 82,4%, accuracy was 89.7% (pConclusions. Magnetic resonance imaging using the diffusion- weighted image Protocol with an assessment of the measured diffusion coefficient has shown high information both in the diagnosis of primary endometrial tumor lesions in primary multiple malignancies, and in establishing the stage of the tumor process and in the diagnosis of subsequent malignancies.

This scientific review assesses the current diagnostic capabilities of diffusion-weighted images used in the magnetic resonance imaging protocol for bladder cancer. It actualizes this impulse sequence employed within the framework of a multiparametric MRI study as one of the functional techniques. The review deals with the possibilities of diffusion-weighted images used in an independent version and in combination with T2-weighted images to visualize a tumor, postoperative changes, and associated pathology. It gives differential diagnostic criteria in identifying the extent of tumor invasion, including that with accuracy assessment according to the measured diffusion coefficient.The sources of the review are publications included in the peer-reviewed databases PubMed, Scopus, eLIBRARY and the open sources Google Scholar, Researchgate.

We present a case that was initially misdiagnosed as drug-related extrapyramidal side effect. However, after the suspected causative drugs were withdrawn, the patient’s condition did not improve. Neuroimaging revealed osmotic demyelination syndrome with a temporal pattern of change from extrapontine myelinolysis to central pontine myelinolysis. Given the limited literature on this rare condition, further research to support clinical diagnosis and treatment is needed.

Objective. To evaluate the efficiency of magnetic resonance spectroscopy in the diagnosis and prognosis of breast cancer (BC).Material and methods. Twenty-eight patients aged 37 to 80 years with established primary invasive BC were examined. Its grade was determined according to pathomorphological verification with immunohistochemical analysis. Breast MRI was performed using the standard protocol, by determining the measured diffusion coefficient (MDC), dynamic contrast enhancement (DCE). Proton magnetic resonance spectroscopy was carried out using the Breeze software package. The clinical and morphological findings and the results of radiation studies were compared to determine Nottingham prognostic index (NPI) scores. To identify the Spearman rank correlation coefficient between MRI findings (the type of pharmacokinetic curves, the total choline-containing (tCho) peak integral) and the values characterizing tumor size and grade.Results. NPI calculation showed that the scoring range was 2.4 to 6.76; the expected 5-year survival rates reached 93%. The mean MDC was 0.856×10-3 mm2/sec; type II pharmacokinetic curve prevailed (n=16; 57.1%). There was a statistically significant negative correlation between the values of MDC, the type of a contrast agent accumulation curve, the levels of HER2/neu and the proliferation marker Ki-67; there was a statistically significant strong positive correlation between the presence of 1H-MPC tCho peak and the indicators determining tumor malignancy (the levels of HER2/neu and Ki-67). Statistically significant differences between the type of a pharmacokinetic curve in DCE and the level of tCho in the prognostic groups defined when calculating NPI were determined in patients with moderate (n=4; 14.2%) and poor (n=10; 35.7%) prognosis.Conclusion. The capabilities of MR spectroscopy are superior in information content to the data obtained by determining the MDC, the nature of contrast medium accumulation in breast tumor, and are comparable with the data determining the type of a tumor (the presence of the HER2/neu gene, Ki-67 proliferation marker) in predicting BC cancer grade and 5-year survival rates.

Highlights • LRD medical image fusion algorithm can be used for glioma grading. • We can use the LRD fusion algorithm with MRI image for glioma grading. • Fusing of DWI (b50) and T1 enhancement (T1Gd) by LRD, have highest diagnostic value for glioma grading., Background Grade of brain tumor is thought to be the most significant and crucial component in treatment management. Recent development in medical imaging techniques have led to the introduce non-invasive methods for brain tumor grading such as different magnetic resonance imaging (MRI) protocols. Combination of different MRI protocols with fusion algorithms for tumor grading is used to increase diagnostic improvement. This paper investigated the efficiency of the Laplacian Re-decomposition (LRD) fusion algorithms for glioma grading. Procedures In this study, 69 patients were examined with MRI. The T1 post enhancement (T1Gd) and diffusion-weighted images (DWI) were obtained. To evaluated LRD performance for glioma grading, we compared the parameters of the receiver operating characteristic (ROC) curves. Findings We found that the average Relative Signal Contrast (RSC) for high-grade gliomas is greater than RSCs for low-grade gliomas in T1Gd images and all fused images. No significant difference in RSCs of DWI images was observed between low-grade and high-grade gliomas. However, a significant RSCs difference was detected between grade III and IV in the T1Gd, b50, and all fussed images. Conclusions This research suggests that T1Gd images are an appropriate imaging protocol for separating low-grade and high-grade gliomas. According to the findings of this study, we may use the LRD fusion algorithm to increase the diagnostic value of T1Gd and DWI picture for grades III and IV glioma distinction. In conclusion, this article has emphasized the significance of the LRD fusion algorithm as a tool for differentiating grade III and IV gliomas.

Creutzfeld-Jakob disease (CJD) is a rare neurodegenerative condition characterized by rapid progression and fatal outcomes. Patients with progressive dementia and associated atypical features should be investigated, especially with the MRI brain for CJD. Cortical ribboning on diffusion-weighted MRI images is a very crucial diagnostic sign for CJD. Here we present a case of a 52-year-old woman admitted to the hospital after a seizure episode and two-month history of altered mental status. She presented with a 40-minute episode of status epilepticus, necessitating admission to the intensive care unit. Head CT showed no acute intracranial abnormalities, and MRI showed generalized brain atrophy. Electroencephalography (EEG) demonstrated an intermittent slowing of the left hemisphere. Two weeks after admission, she got discharged. Four days later, she presented to the hospital after being found disoriented in a park. MRI showed ventricular dilation and a questionable focus of restricted diffusion in the left thalamus posteriorly. CJD protein panel was collected. Three days after discharge, she was brought to the hospital, and CJD protein testing revealed the presence of 14-3-3 protein, elevated T-tau, and negative real-time quaking-induced conversion (RT-QuIC). The National Prion Disease Surveillance Center reviewed her case, and the CJD diagnosis was confirmed.

Cerebral fat embolism (CFE) syndrome is relatively rare in clinical practice. Currently, there is no uniform standard of magnetic resonance imaging for the diagnosis of the disease. In this report, we present head computed tomography and magnetic resonance images (T2-weighted images, fluid-attenuated inversion recovery images, diffusion-weighted images, and susceptibility-weighted images) in a case of CFE. This report explains the imaging characteristics of CFE and improves the clinician’s understanding of this disease and its etiology.

Применение МРТ с модальностью ДВИ успешно может быть использовано для оптимизации ранней диагностики и прогнозирования развития возможной ХПН у пациентов на ранних стадиях ПКР до проведения оперативного лечения при отсутствии лучевой нагрузки на пациента.В результате проведенной работы было установлено, что на ранних стадиях ПКР в 38,23% случаев до проведения хирургического лечения наблюдалось снижение ИКД интактного участка коры пораженной опухолевым процессом почки на диффузионно-взвешенных изображениях МРТ по сравнению со значением ИКД нормальной почечной коры (контрольная группа). Также была получена прямая корреляция между значениями ИКД интактного участка коры пораженной опухолью почки на диффузионно-взвешенных изображениях МРТ до операции и показателями СКФ через 12 месяцев после резекции почки в той же группе пациентов. Важным моментом являлось то, что в ходе исследования было установлено, что использование ИКД диффузионно-взвешенных изображений МРТ в дооперационном периоде позволяет прогнозировать снижение СКФ интактного участка коры пораженной опухолью почки в послеоперационном периоде у пациентов со II стадией ПКР после ее резекции, что является важным для прогнозирования появления и метафилактики развития ХПН у данной категории пациентов., The use of MRI with DWI modality can be successfully used to optimize early diagnosis and predict the development of possible chronic renal failure in patients at early stages of RCC before surgical treatment in the absence of radiation exposure.As a result of the work, it was found that in patients at the early stages of RCC in 38.23% of cases, before surgical treatment, there was the decrease in the ADC of the intact cortex of the tumor- affected kidney in diffusion-weighted MRI images, if compared with the value of the ADC of the normal renal cortex (control group).There was also obtained a direct correlation between the ADC values of the intact cortex of the affected tumor in the diffusion-weighted MRI images before surgery and GFR values in 12 months after kidney resection in the same group of patients. During the study, it was found that the use of ADC of diffusion-weighted MRI in the preoperative period lets to predict the decrease in GFR of the intact cortex of the affected tumor in the postoperative period in patients with the stage II of RCC after its resection, which is important for predicting the appearance and metaphylaxis of the development of chronic renal failure in this category of patients., Евразийский онкологический журнал, Выпуск 2 2020

Highlights • Estimation of the corticospinal tract in patients with gliomas based on diffusion kurtosis tensor imaging using a 1.5T magnetic field showed similar proprieties as the tracts reconstructed using diffusion tensor tractography., Tractography studies for pre-surgical planning of primary brain tumors is typically done using diffusion tensor imaging (DTI), which cannot resolve crossing, kissing or highly angulated fibres. Tractography based on the estimation of the diffusion kurtosis (DK) tensor was recently demonstrated to enable tackling these limitations. However, its use in the clinical context at low 1.5T field has not yet been reported. Purpose To evaluate if the estimation of whole-brain tractography using the DK tensor is feasible for pre-surgical investigation of patients with brain tumors at 1.5T. Methods Eight healthy subjects and 3 patients with brain tumors were scanned at 1.5T using a 12-channel head coil. Diffusion-weighted images were acquired with repetition/echo times of 5800/107 ms, 82 × 82 resolution, 3 × 3 × 3 mm3 voxel size, b-values of 0, 1000, 2000 s/mm2 and 64 gradient sensitising directions. Whole-brain tractography was estimated using the DK tensor and corticospinal tracts (CST) were isolated using regions-of-interest placed at the cerebral peduncles and motor gyrus. Tract size, DK metrics and CST deviation index (highest curvature point) were compared between healthy subjects and patients. Results Tract sizes did not differ between groups. The CST deviation index was significantly higher in patients compared to healthy subjects. Fractional anisotropy was significantly lower in patients, with higher mean kurtosis asymmetry index at the highest curvature point in patients. Conclusions Corticospinal fibre bundles estimated using DK tensor in a 1.5T scanner presented similar properties in patients with brain gliomas as those reported in the literature using DTI-based tractography.

Acquired ear canal stenosis can be caused by trauma, inflammation, postoperative scar formation, or tumors. There is a risk of cholesteatoma formation because of keratinized deposits in the closed space, with a reduction in quality of life because of conductive hearing loss. A cholesteatoma that has grown in a closed external auditory canal is difficult to find because of its location and the original hearing loss because of ear canal stenosis. Regarding imaging for cholesteatoma, CT absorption values are nonspecific, but MRIs are said to be effective. In an MRI, diffusion-weighted images are useful for distinguishing cholesteatoma. In surgery for ear canal stenosis, it is important to adopt strategies that will prevent post-operative restenosis and re-closure. If a cholesteatoma is also present, besides excising it, the ear canal should be enlarged. It is also important to follow-up patients with traumatic ear canal stenosis. We present a case of cholesteatoma associated with traumatic ear canal stenosis discovered 50 years after injury. Here, the cholesteatoma was diagnosed by MRI, and the external ear canal was enlarged during surgery. No postoperative recurrence was observed during follow-up.

The aim is to evaluate the diagnostic potential of the diffusion-weighted MRI sequences (DW-MRI) as compared with multi-spiral computed tomography (MSCT) for staging of ovarian malignancies (OVM).Materials and Methods. The study was conducted (from February to December 2016) on 73 patients with suspected ovarian malignancies who underwent preoperative examination, including abdominal / pelvic MSCT and DW-MRI, using a 1.5T scanner with b-factors of 0.1000 s/mm2 and the calculation of apparent diffusion coefficient (ADC). Using the obtained data, the peritoneal cancer index (PCI) was calculated and ROC curves for DW-MRI vs MSCT were created. The imaging-based diagnoses were then compared with surgical staging and histopathological examination.Results. The following stages of OVM were determined: 5 (6.8%) IV; 35 (47.9%) IIIC; 23 (31.5%) IIIB; 10 (13.6%) IIIA. The overall sensitivity was 55% for MSCT and 77% for DW-MRI. For example, DW-MRI was markedly superior to MSCT in detecting a tumor implantation into the large intestine mesentery (83.8% and 37.8%, respectively), into the small intestine serosa (77.8% and 28.9%), and the para-aortic lymph nodes (71.4 and 35.7%). The specificity of the compared imaging modalities was similar (79.6% – DW-MRI and 81% – MSCT). The peritoneal cancer index (PCI) calculated from the DW-MRI results correlated with the surgical staging data better than the PCI based on MSCT (r=0.706 for DW-MRI, r=0.544 for MSCT). Based on the obtained data, the ROC curves were plotted to show the areas under the curves of 0.913 and 0.655 for DW-MRI and MSCT, respectively. A decrease in the ADC values was found in secondary tumor foci (1.120±0.25 for the ovaries, 0.820±0.23 for the omentum, 0.790±0.19Ч10-3 mm2/s for peritoneal implants).Conclusion. For the assessment of ovar-ian cancer spread, DW-MRI is significantly more sensitive than MSCT.

Currently, malignant tumors of ovaries take the third place in the structure of oncogynecological diseases, being a leading cause of death among pathology of female reproductive system. Due to the lack of effective screening programs and asymptomatic course of the disease in its early stages, in the majority of cases ovarian cancer (OC) is detected in form of disseminated process, what greatly reduces the effectiveness of primary treatment and has a negative impact on the further prognosis. In connection with the above, timely diagnosis and organization of OC screening, as well as monitoring of its recurrence is a major problem for oncologists around the world. In the present literature review the opportunities of magnetic — resonance imaging (MRI) in detection of primary ovarian cancer and its recurrence are considered, the analysis of the method diagnostic efficiency based on the use of various techniques is done. The opportunities of MRI show a lot of information necessary for the characterization of detected ovarian formations, estimates of the prevalence of primary ovarian cancer and its recurrence. However, the analysis of performed literature revealed a significant lack of materials devoted to the definition of the diagnostic capabilities of various MRI techniques, including diffusion — weighted imaging (DWI), what indicates the necessity for further studies in this direction.

Background: White matter hyperintensities (WMH) are a common finding in aged individuals affected by carotid artery disease and are a risk factor for first-ever and recurrent stroke. We investigated if white matter damage increases the risk of brain microembolism during carotid artery stenting (CAS), as evaluated by the appearance of new areas of restricted diffusion on diffusion-weighted images (DWI). Methods: We evaluated 47 patients with severe internal carotid artery (ICA) stenosis undergoing CAS, comparing preprocedural clinical, ultrasound and radiological characteristics. WMH volume was computed on FLAIR images before CAS. After CAS, the DWI scan was looked over for areas of restricted diffusion (DWI lesions). A first univariate analysis was adopted to compare groups according to the occurrence of DWI lesions. Then, the variable DWI lesion was modelled by means of a logistic regression model. Results: Seventeen patients developed at least 1 DWI lesion after CAS. Compared with non-DWI, DWI patients were more commonly treated in the left ICA (p = 0.007) and had a more severe WMH damage (p = 0.027). Indeed, the risk of a DWI lesion was higher in left versus right stenosis (OR = 9.0, 95% CI 1.9-42.7, p = 0.005) and increased for each log-unit of WMH lesion load (OR = 7.05, 95% CI 1.07-46.49, p = 0.042). A WMH lesion load of at least 5.25 cm3 had a 50% probability of occurrence of a new DWI lesion. Conclusions: Treated side and preexisting white matter damage are risk conditions for brain microembolism during CAS. This should be taken into account to optimize severe carotid artery disease management.

Purpose High-resolution isotropic T-2 mapping of the human brain with multi-echo spin-echo (MESE) acquisitions is challenging. When using a 2D sequence, the resolution is limited by the slice thickness. If used as a 3D acquisition, specific absorption rate limits are easily exceeded due to the high power deposition of nonselective refocusing pulses. A method to reconstruct 1-mm(3) isotropic T-2 maps is proposed based on multiple 2D MESE acquisitions. Data were undersampled (10-fold) to compensate for the prolonged scan time stemming from the super-resolution acquisition. Theory and Methods The proposed method integrates a classical super-resolution with an iterative model-based approach to reconstruct quantitative maps from a set of undersampled low-resolution data. The method was tested on numerical and multipurpose phantoms, and in vivo data. T-2 values were assessed with a region-of-interest analysis using a single-slice spin-echo and a fully sampled MESE acquisition in a phantom, and a MESE acquisition in healthy volunteers. Results Numerical simulations showed that the best trade-off between acceleration and number of low-resolution datasets is 10-fold acceleration with 4 acquisitions (acquisition time = 18 min). The proposed approach showed improved resolution over low-resolution images for both phantom and brain. Region-of-interest analysis of the phantom compartments revealed that at shorter T-2, the proposed method was comparable with the fully sampled MESE. For the volunteer data, the T-2 values found in the brain structures were consistent across subjects (8.5-13.1 ms standard deviation). Conclusion The proposed method addresses the inherent limitations associated with high-resolution T-2 mapping and enables the reconstruction of 1 mm(3) isotropic relaxation maps with a 10 times faster acquisition.

Uterine myxoid leiomyosarcomas (MLMSs) are extremely rare. Here, we report a rare case of uterine MLMS with unique and bizarre magnetic resonance imaging (MRI) findings on diffusion-weighted images (DWIs) and dynamic contrast-enhanced (DCE) MRI scans. A 67-year-old woman presented with a uterine MLMS that had a multilocular cystic mass with a septum and solid components. The tumour demonstrated marked hyperintensity on T2-weighted images in a myxoid stroma with gradual partial contrast enhancement and diffusion restriction, which could be a characteristic feature suggestive of a myxoid malignant smooth muscle tumour of the uterus rather than a uterine leiomyoma with myxoid degeneration.

Objective: to determine whether the measurable diffusion coefficient (MIC) may be used to differentiate normal and lymphomatosisaltered lymph nodes (LNs) in patients with Hodgkin lymphoma (HL).Material and methods. Whole-body magnetic resonance (MR) imaging was used to compare the MICs of LNs in 27 apparently healthy individuals and 41 patients with a verified diagnosis of HL.Results. Construction of 95% confidence intervals showed that the MICs of normal LNs were in the range of 1.00 to 1.73× ×10-3 mm2/sec and significantly higher (p

Objective Conus medullaris teratomas are very rare tumors. Traditional preoperative diagnosis depended on the findings from magnetic resonance imaging (MRI). Tractography is a novel technique that has recently been utilized to diagnose spinal cord lesions. This case report shows that fiber tractography has great potential in preoperative diagnosis and postoperative follow-up of teratomas of the conus medullaris. Methods A 50-year-old man with a conus medullaris teratoma underwent tractography with the aim of visualizing the tumor in relation to the white matter tracts. The patient underwent a T12–L2 laminectomy, and the lesion was resected. The histopathology diagnosis was of a mature teratoma. Study Design Case report. Results Diffusion tensor imaging (DTI) and tractography provide more details about the white matter tracts in relation to space-occupying lesions that may be more sensitive than conventional MRI and have recently been utilized in spinal cord lesions. Fiber tracking has the ability to visualize the integrity of the white matter tracts at the level of the conus medullaris in relation to the lesion. The tracts appeared to be displaced by the lesion at the conus medullaris. Tractography also showed no white matter tracts within the lesion. Such findings are consistent with the characteristics of a benign lesion. Exploiting tractography in this case was helpful in predicting the nature of the lesion preoperatively and in planning the surgical intervention. Conclusions Conus medullaris teratomas mostly affect adults. Patients generally present with a long history of clinical symptoms prior to diagnosis. Surgery is required for diagnosis, and the goal should be complete tumor excision without sacrificing any neurologic functions. The use of DTI and tractography, in addition to conventional MRI, has the potential to be very valuable for the diagnosis, surgical planning, and follow-up of patients with conus medullaris teratomas.

Background: Mucoepidermoid carcinoma (MEC) is a rare tumor of the lung that accounts for 0.1–0.2% of all pulmonary tumors. To the best of our knowledge, brain metastasis from lung MEC is rare and magnetic resonance imaging (MRI) findings of this lesion have not been documented. Case Description: We herein report the case of a 72-year-old male. MRI revealed a left parietal tumor showing ring enhancement with medium gadolinium contrast and an evident high intensity area in the nonenhanced central portion on diffusion-weighted images (DWI) mimicking a brain abscess. Histologically, MEC is composed of a mixture of different cell types including mucin-secreting glandular cells and squamous cells. Accordingly, we suggest that the high DWI signal can be explained by the development of intracellular and intraluminal mucin, which have a high viscosity. Conclusion: Further accumulation of cases with brain metastasis from MEC is needed to establish the characteristic image findings, which would lead to prompt and adequate treatment.

Dengue is a common viral infection worldwide with presentation varying from clinically silent infection to dengue fever, dengue hemorrhagic fever, and severe fulminant dengue shock syndrome. Neurological manifestation usually results from multisystem dysfunction secondary to vascular leak. Presentation as hemorrhagic encephalitis is very rare. Here we present the case of a 13-year-old female admitted with generalized tonic clonic seizures. Plain computed tomography (CT) scan of head revealed hypodensities in bilateral deep gray matter nuclei and right posterior parietal lobe without any hemorrhage. Cerebrospinal fluid (CSF) and serology were positive for IgM and IgG antibodies to dengue viral antigen. Contrast-enhanced magnetic resonance imaging (MRI) revealed multifocal T2 and fluid attenuated inversion recovery (FLAIR) hyperintensities in bilateral cerebral parenchyma including basal ganglia. No hemorrhage was seen. She was managed with steroids. As her clinical condition deteriorated, after being stable for 2 days, repeat MRI was done which revealed development of hemorrhage within the lesions, and diagnosis of acute hemorrhagic encephalitis of dengue viral etiology was made.

Background High-intensity focused ultrasound (HIFU) is an emerging technique for noninvasive ablative treatment. However, HIFU has rarely been performed for the treatment of soft-tissue tumors. Thus, we aimed to assess the feasibility and safety of performing extracorporeal HIFU for the treatment of soft-tissue tumor. The treatment response was assessed using functional magnetic resonance imaging (MRI) techniques. Materials and methods In the rabbit VX2 intramuscular tumor model, HIFU was performed using an extracorporeal HIFU device (YDME FEP-BY02) by varying the electric power from 50 to 400 W, with the other parameters being fixed. The HIFU beam was insonated to one layer of focal spots having a depth of 8 mm. The degree of ablation was evaluated by histological examination and functional MRI techniques including dynamic contrast-enhanced MRI (DCE-MRI) and apparent diffusion coefficient (ADC) map. The presence of skin burn was also evaluated. Results Applying HIFU with an electric power of 200 W discretely produced the ablation zone without skin burn as planned before treatment (maximal depth: 8–9 mm), which shows the suitability of using HIFU (with 200 W electric power) for the treatment of soft-tissue tumors. By contrast, HIFU with an electric power of 100 W produced an ill-marginated ablation zone with internal residual tumor foci, and HIFU with 300–400 W produced ablation zones with a maximum depth of 13–24 mm, which far exceeded the planned depth and caused skin burn. Perfusion maps of DCE-MRI demonstrated the devascularized ablation zone more conspicuously than conventional contrast-enhanced T1-weighted images, and ADC map demonstrated the surrounding edema or granulation tissue better than conventional T2-weighted images. Conclusion Extracorporeal HIFU treatment for soft-tissue tumor may be a feasible approach with adjustment of input energy level. For post-treatment assessment, functional MRI techniques including DCE-MRI and ADC map may be useful and complementary to conventional MRI.

Heroin has physical effects on many parts of the body, for example, respiratory and digestive system, muscles, and nervous system. Neurologic complications include brain abscess, neuropathy, transverse myelitis, and leukoencephalopathy.Magnetic resonance image is more sensitive in detecting lesions with low signal on T1W and high signal on T2W, and FLAIR images in the white matter and other areas of brain. Imaging findings are similar to other leukoencephalopathies (hereditary diseases, abnormal metabolic diseases, and intoxications).In the course of finding ways to differentiate heroin-induced spongiform leukoencephalopathy from other leukoencephalopathies, attention has been changed to diffusion magnetic resonance imaging in recent years.Nevertheless, studies do not verify that diffusion-weighted image is a valuable tool in establishing the diagnosis.

Purpose. Optimization of previously developed verification methods for the analysis of MRI data measured in healthy volunteers and patients. Analysis of axonal fiber tracking in the area of hemorrhagic stroke for better detection of damaged paths and areas in the brain. To indentify the correlation parameters with the severity of injury. Materials and methods. Axonal tractography was performed on a digital phantom with predetermined tracts trajectories and on volunteers and patients, measured on a clini-cal 1.5 T scanner with parameters specific to routine clinical measurements and on 3T ex-pert class scanner specially designed for the measurement of diffusion, which provides data with a higher spatial resolution and signal to noise ratio. Verification of the tractography results was based on proposed earlier methods of probability calculation and Shannon in-formation entropy along the paths. Results. It was found that the probability was better than the entropy in path direc-tion characterization and the entropy allowed determining the area of intersection and the branching of paths. A certain correlation was found between the degree of injury and the amount of entropy in the affected area. Conclusions. The combination of entropy and the probability of diffusion along the axonal tracts allows to estimate the probability of passage routes particular trajectory and thus can serve as a measure criterion of the reliability of the axonal tractography results. Entropy allows to evaluate the severity of the lesions, but this hypothesis needs further in-vestigation in more patients.

INTRODUCAO: Anormalidades transitorias de imagem, incluindo imagens de ressonância magnetica por difusao (DWI), podem ser vistas no status epilepticus. Essas anormalidades podem ser seguidas de esclerose hipocampal. RELATO DE CASO: Nos relatamos uma jovem de 15 anos com status focal nao convulsivo e lentificacao focal no EEG. DWI mostrava sinal hiperintenso em regioes temporais bilaterais e cortex insular. Apos 3 semanas, RM de encefalo mostrava atrofia localizada do hipocampo. CONCLUSAO: Os achados de RM indicam edema vasogenico e citotoxico durante as crises epilepticas com subsequente atrofia de parenquima cerebral.

BACKGROUND: Transient imaging abnormalities, including changes on diffusion-weighted imaging (DWI), may be seen in status epilepticus. These abnormalities can be followed by hippocampal sclerosis. CASE REPORT: We report a 15-year-old lady with focal non convulsive status epilepticus (NCSE) and focal slowing on EEG. DWI exhibited abnormal hyperintense signals in bilateral temporal and insular cortices. After 3 weeks, MRI performed a localizated hippocampal atrophy. CONCLUSION: The MRI findings indicated vasogenic and cytotoxic edema during seizure activity and subsequent loss of brain parenchyma.INTRODUÇÃO: Anormalidades transitórias de imagem, incluindo imagens de ressonância magnética por difusão (DWI), podem ser vistas no status epilepticus. Essas anormalidades podem ser seguidas de esclerose hipocampal. RELATO DE CASO: Nós relatamos uma jovem de 15 anos com status focal não convulsivo e lentificação focal no EEG. DWI mostrava sinal hiperintenso em regiões temporais bilaterais e córtex insular. Após 3 semanas, RM de encéfalo mostrava atrofia localizada do hipocampo. CONCLUSÃO: Os achados de RM indicam edema vasogênico e citotóxico durante as crises epilépticas com subseqüente atrofia de parênquima cerebral.

The aim of this study was to verify the sensitivity and specificity of the hyperdense middle cerebral artery sign (HMCAS) obtained by multidetector computed tomography (CT) in predicting acute stroke, using diffusion-weighted (DW) magnetic resonance imaging (MRI) as a reference. The location of the HMCAS, the extension of the ischaemic lesion and its prognostic value were also assessed.The CT examinations of 654 patients with symptoms related to acute cerebral stroke were retrospectively reviewed. DW-MRI confirmed recent stroke in 175 patients. Two expert neuroradiologists analysed the CT examinations of these patients in four phases. Sensitivity, specificity and interobserver reliability was evaluated. Patients were divided into three groups according to the HMCAS site (M1-M2-M3) and the Alberta Stroke Program Early CT Score (ASPECTS) on DW-MRI was calculated. The ASPECTS average score was correlated with the National Institutes of Health Stroke Scale (NIHSS) and modified Rankin scale (mRS) at 3 months.In 41 patients, the presence of HMCAS was confirmed (71 % sensitivity; 100 % specificity; Interobserver reliability k, 84 %). An inverse correlation was found by comparing the ASPECTS and NIHSS scores (Rsq = -0.206). After logistic regression analysis, HMCAS was found to be independently associated with a poor outcome (mRS2) at 3 months after adjusting for age, NIHSS on admission, risk factors and aetiology of stroke.Our study demonstrated that HMCAS obtained with multidetector CT can be detected in more than 70 % of patients with large acute ischaemic lesion and it is an unfavourable prognostic sign.

Introduction: Corticobasal syndrome (CBS) has a heterogeneous clinical presentation with no specific pathologic substratum. Its accurate diagnosis is a challenge for neurologists; in order to establish CBS definitively, postmortem confirmation is required. Some clinical and radiological features can help to distinguish it from other neurodegenerative conditions, such as Creutzfeldt-Jakob disease (CJD). Clinical Case: A 74-year-old woman presented with language impairment, difficulty in walking and poor attentiveness that had begun 10 days before. Other symptoms, such as asymmetrical extra-pyramidal dysfunction, limb dystonia and ‘alien limb’ phenomena, were established over the next 2 months, with rapid progression. Death occurred 3 months after symptom onset. Laboratory results were normal. Initially, imaging only showed restricted diffusion with bilateral parieto-occipital gyri involvement on DWI-MRI, with unspecific EEG changes. An autopsy was performed. Brain neuropathology confirmed sporadic CJD (sCJD). Conclusions: CBS is a heterogeneous clinical syndrome whose differential diagnosis is extensive. CJD can occasionally present with clinical characteristics resembling CBS. MRI detection of abnormalities in some sequences (FLAIR, DWI), as previously reported, has high diagnostic utility for sCJD diagnosis – especially in early stages – when other tests can still appear normal. Abnormalities on DWI sequencing may not correlate with neuropathological findings, suggesting a functional basis to explain the changes found.

BACKGROUND: Transient imaging abnormalities, including changes on diffusion-weighted imaging (DWI), may be seen in status epilepticus. These abnormalities can be followed by hippocampal sclerosis. CASE REPORT: We report a 15-year-old lady with focal non convulsive status epilepticus (NCSE) and focal slowing on EEG. DWI exhibited abnormal hyperintense signals in bilateral temporal and insular cortices. After 3 weeks, MRI performed a localizated hippocampal atrophy. CONCLUSION: The MRI findings indicated vasogenic and cytotoxic edema during seizure activity and subsequent loss of brain parenchyma. INTRODUÇÃO: Anormalidades transitórias de imagem, incluindo imagens de ressonância magnética por difusão (DWI), podem ser vistas no status epilepticus. Essas anormalidades podem ser seguidas de esclerose hipocampal. RELATO DE CASO: Nós relatamos uma jovem de 15 anos com status focal não convulsivo e lentificação focal no EEG. DWI mostrava sinal hiperintenso em regiões temporais bilaterais e córtex insular. Após 3 semanas, RM de encéfalo mostrava atrofia localizada do hipocampo. CONCLUSÃO: Os achados de RM indicam edema vasogênico e citotóxico durante as crises epilépticas com subseqüente atrofia de parênquima cerebral.

In order to investigate epilepsy, that is one of the most common neurological disorders, in the last decades different animal models have been proposed. Prevention, diagnosis, treatment and basic knowledge have been improved by the mean of these models. Numerous animal models have been developed in epilepsy research, both for generalized and for simple/complex partial seizures. Animal models for generalized seizures include sensory (light, noise, movement, etc) or electrical stimulations and genetic models. Models for focal seizures include topical or systemic application of pro-convulsive compounds or electrical stimulation. Baboons, mice, rats, rabbits, and Fayoumi chicken have been extensively used in this regard. Since 1983, when magnetic resonance spectroscopy was used to evaluate for the first time in vivo alterations induced by status epilepticus in rabbit, an increasing interest for the neuroimaging perspective has led to new insights in the study of epileptic disorders. In the early 1990s experimental studies provided evidence for the feasibility of magnetic resonance imaging analysis and detection of tissue damage in kainic acid-induced epilepsy in rat. In the following years a wealth of data has been obtained by the mean of functional MRI and/or by diffusion-weighted images. The studies reported in the literature of the last decades indicate in vivo magnetic resonance of epilepsy model as valuable and extremely informative tool.

PurposeTo evaluate the diagnostic impact of echo planar DW imaging in distinguishing benign from malignant musculoskeletal soft-tissue masses using ADC mapping as a quantitative assessment tool.Patients and methodsWe evaluated 73 tumors (21 bone tumors and 52 soft-tissue tumors). MR examinations were performed with a 1.5-T system. Diffusion-weighted single-shot EPI images were obtained in all patients. Apparent diffusion coefficients (ADCs) were calculated by using b factors of 0 and 1000s/mm2. ADC value measurements were compared with the histopathological findings.ResultsThe average ADC of benign tumors was 1.86±0.67×10−3mm2/s, and that of malignant soft-tissue tumors was 0.97±0.35×10−3mm2/s. ADC value of malignant tumors was significantly lower than that of the benign tumor group (p

Indices derived from diffusion tensor imaging (DTI) data, including the mean diffusivity (MD) and fractional anisotropy (FA), are often used to better understand the microstructure of the brain. DTI, however, is susceptible to imaging artefacts, which can bias these indices. The most important sources of artefacts in DTI include eddy currents, nonuniformity and mis-calibration of gradients. We modelled these and other artefacts using a local perturbation field (LPF) approach. LPFs during the diffusion-weighting period describe the local mismatches between the effective and the expected diffusion gradients resulting in a spatially varying error in the diffusion weighting B matrix and diffusion tensor estimation. We introduced a model that makes use of phantom measurements to provide a robust estimation of the LPF in DTI without requiring any scanner-hardware-specific information or special MRI sequences. We derived an approximation of the perturbed diffusion tensor in the isotropic-diffusion limit that can be used to identify regions in any DTI index map that are affected by LPFs. Using these models, we simulated and measured LPFs and characterised their effect on human DTI for three different clinical scanners. The small FA values found in grey matter were biased towards greater anisotropy leading to lower grey-to-white matter contrast (up to 10%). Differences in head position due to e.g. repositioning produced errors of up to 10% in the MD, reducing comparability in multi-centre or longitudinal studies. We demonstrate the importance of the proposed correction by showing improved consistency across scanners, different head positions and an increased FA contrast between grey and white matter., Highlights ► Measurement of local perturbation fields (LPFs) on three different scanners. ► LPFs are, e.g., diffusion-gradient non-linearities/mis-calibration. ► LPFs bias fractional anisotropy (FA) and mean diffusivity (MD) maps. ► Correction improves accuracy, FA contrast and comparability between scanners. ► Relevant for group, longitudinal or multi-centre studies.