Extensive myelitis associated with anti-NMDA receptor antibodies.

International audienceBACKGROUND: Encephalitis with anti-N-methyl-D-aspartate receptor antibodies (anti-NMDAR-Ab) is a rapid-onset encephalitis including psychosis, seizures, various movement disorders and autonomic system disturbances. CASE PRESENTATION: We report a very unusual case of extensive myelitis associated with anti-NMDAR-Ab. MRI also revealed a hyperintense T2 lesion, non-suggestive of MS, which progressively extended, associated with periventricular gadolinium enhancement visualized on brain MRI. Ophthalmological evaluation showed subclinical right optic neuritis. The absence of anti-AQP4 antibody argued against neuromyelitis optica spectrum disorder. A slight psychomotor slowing prompted us to search for various causes of autoimmune encephalitis. Anti-NMDAR-Ab was found in cerebrospinal fluid. CONCLUSION: In patients with extensive myelitis who are seronegative for anti-AQP4 antibodies, and after other classical causes have been excluded, the hypothesis of atypical anti-NMDAR-Ab encephalitis should also be considered

Volumetric relief map for the cortical subarachnoid space analysis

Purpose: Medical image visualization is an important step in the medical diagnosis of hydrocephalus. In this paper, we present planar representations called volumetric relief maps that are generated from three-dimensional images of the cerebrospinal fluid within the cortical subarachnoid space. Such maps are visually interpreted at once and allow to automatically characterize fluid distributions. Consequently, they help specialists to provide a diagnosis and to monitor patients instantly. Methods: Volumetric relief maps are generated by enclosing the cortical subarachnoid space with a hemisphere, and using a ray tracing method and a map projection technique from a hemisphere to a plane. Results: Visualization of maps indicates that healthy adults have more balanced fluid distributions with well-filled sulci, unlike hydrocephalus patients who have more or less large fluid depletions in the posterior regions of the brain. We showed that a moment-based approach allows to efficiently characterize such fluid distributions from maps. In particular, the center of mass of a distribution is an efficient discriminant factor to distinguish between healthy adults and hydrocephalus patients, with resulting sensitivity and specificity of 100%. In addition, we have noted that asymmetry of the fluid distribution increases with depletion for hydrocephalus patients; such asymmetry is generally oriented towards the frontal part of the fissura longitudinalis cerebri. Conclusions: This paper describes an innovative visualization tool used to analyze fluid distribution within the cortical subarachnoid space. It allows to efficiently discriminate between healthy adults and pathological cases, and to monitor patients before and after surgery

Volumetric relief map for intracranial cerebrospinal fluid distribution analysis

International audienceCerebrospinal fluid imaging plays a significant role in the clinical diagnosis of brain disorders, such as hydrocephalus and Alzheimer's disease. While three-dimensional images of cerebrospinal fluid are very detailed, the complex structures they contain can be time-consuming and laborious to interpret. This paper presents a simple technique that represents the intracranial cerebrospinal fluid distribution as a two-dimensional image in such a way that the total fluid volume is preserved. We call this a volumetric relief map, and show its effectiveness in a characterization and analysis of fluid distributions and networks in hydrocephalus patients and healthy adults

Characteristics of Moyamoya Syndrome in Sickle-Cell Disease by Magnetic Resonance Angiography: An Adult-Cohort Study

Background: Sickle cell disease (SCD) can be complicated by moyamoya syndrome. Brain magnetic resonance angiography (MRA) is a non-invasive method to diagnose this syndrome and, steno-occlusion and moyamoya vessels (MMV) scores have been proposed to evaluate its severity. Previous studies of SCD moyamoya syndrome did not evaluate the severity according to MRA scores. The objective was to assess the characteristics of moyamoya syndrome in an adult cohort of SCD using these MRA scores.Methods: Twenty-five SCD patients with moyamoya syndrome were included using MRA with 3D time of flight technique. We evaluate steno-occlusion score for each hemisphere (range 0–10) from: steno-occlusion severity of internal carotid (ICA) (0–3), anterior cerebral (ACA) (0–3), middle cerebral (MCA) (0–2), and posterior cerebral (PCA) (0–2) arteries. MMV score for each hemisphere (range 0–5) depended from 5 MMV areas: (1) anterior communicating artery (2) basal ganglia (3) ICA/MCA (4) posterior communicating artery/PCA (5) basilar artery.Results: Eight patients (32%) showed unilateral moyamoya syndrome. ICA steno-occlusion was involved in 22 patients (88%), MCA in 23 patients (92%), ACA in 9 patients (36%), and PCA in 3 patients (12%). MMV involved ACoA area in 10 patients (40%), basal ganglia in 13 patients (52%), PCoA/PCA in 10 patients (40%), MCA/ICA in 7 patients (28%), and BA in 1 patient (4%). Steno-occlusion and MMV mean hemisphere scores were 3.4/10 (± 1.42) and 1.6/5 (± 0.71), respectively.Conclusion: Frequent unilateral moyamoya syndrome, uncommon PCA involvement and, moderate steno-occlusion and MMV scores seem to be features of SCD moyamoya syndrome. In future studies, MRA scores could be collected to assess the follow-up in these patients

Nouvelle méthode pour la reconstruction 3D de la voûte crânienne humaine à partir de CT-scans

peer reviewedaudience: researcher, professionalThis study presents a new method for the 3D reconstruction of the human cranial vault from routine Computed Tomography (CT) data. The reconstruction method was based on the conceptualization of the shape of the cranial vault with a parametric description. An initialization was first realized with the identification of anatomical landmarks and contours on Digitally Reconstructed Radiographs (DRR) in order to obtain a pre-personalized reconstruction. Then an optimization of the reconstruction was performed to segment the internal and external surfaces of the cranial vault for thickness computation. The method was validated by comparing final reconstructions issued from our approach and from a manual sliceby- slice segmentation method on ten CT-scans. Errors were comparable to the CT image resolution, and less than 2 min were dedicated to the operatordependant marking step. The reconstruction of internal and external surfaces of the cranial vault allows quantifying and visualizing of thickness throughout the cranial vault. This thickness mapping is useful for clinical purposes as additional pre-surgical information. Moreover, this study constitutes a first step in the personalized characterization of skull resistance directly from routine exams

Gliomatosis Cerebri Type 1 Mimicking an Ischemic Stroke and Progressing to a Type 2: a Case Study and Literature Review

Aims: To report a rare clinical case of gliomatosis cerebri, which presented with nonspecific clinical, laboratory, and radiological findings. We provide images and stress the importance of differential diagnosis based on imaging, especially magnetic resonance (MR) spectroscopy. Case Presentation: A 73-year-old woman developed a right hemiplegia suggestive of ischemic stroke. Cerebral magnetic resonance imaging (MRI) highlighted a diffuse tumor-related infiltration involving several lobes without contrast enhancement, corresponding to the specific description and definition of gliomatosis cerebri type 1. With the aid of MR spectroscopy, we correctly diagnosed the disease preoperatively, which was finally confirmed pathologically by stereotactic biopsy. During radiological follow-up, a contrast enhancement occurred on cerebral MRI, suggestive of progression to a gliomatosis cerebri type 2. Given a poor performance status, this elderly patient received palliative treatment. Discussion: Gliomatosis cerebri is a relatively rare but well-known entity, which affects mostly middle aged patients. It often presents with confounding clinical and imaging features, thus additional examinations such as MR spectroscopy are almost always necessary before reaching the correct diagnosis before biopsy. Conclusion: Contrast enhancement on cerebral MRI, which is usually absent, is found in case of transformation from type 1 gliomatosis cerebri to type 2. Some features on MR spectroscopy are helpful for gliomatosis cerebri diagnosis: N-acetylaspartate levels are diminished, levels of myoinositol are significantly elevated, but Cho/Cr ratio may be normal

Cerebrospinal fluid volume analysis for hydrocephalus diagnosis and clinical research

International audienceIn this paper we analyze volumes of the cerebrospinal fluid spaces for the diagnosis of hydrocephalus, which are served as reference values for future studies. We first present an automatic method to estimate those volumes from a new three-dimensional whole body magnetic resonance imaging sequence. This enables us to statistically analyze the fluid volumes, and to show that the ratio of subarachnoid volume to ventricular one is a proportionality constant for healthy adults (=10.73), while in range [0.63, 4.61] for hydrocephalus patients. This indicates that a robust distinction between pathological and healthy cases can be achieved by using this ratio as an index

Relief map of the upper cortical subarachnoid space

International audienceThis paper proposes a method to retrieve a two-dimensional relief map of the cerebrospinal fluid distribution in the upper cortical subarachnoid space from three-dimensional magnetic resonance images. This new representation provides both qualitative and quantitative information on the fluid distribution that surrounds the brain. Relief maps can efficiently be used for the diagnosis and the monitoring of hydrocephalus patients

Volume Assessment of the Cerebrospinal Fluid Spaces for Computer Aided Diagnosis

The present work aims to provide support in the diagnosis of hydrocephalus, which requires an assessment to the volumes of the cerebrospinal fluid (CSF) within its total, ventricular and subarachnoid spaces. In this paper we describe a fully automatic method to estimate the CSF volumes from a new 3D whole body MR imaging sequence. The method was developed using image properties as well as anatomical and geometrical features, completed with a topological assumption on the CSF shape. Experiments on phantoms and clinical data were performed and evaluated by comparing our assessments of volumes with those derived from a segmentation controlled by expert physicians. Then we show that a robust distinction between pathological cases and healthy adult people can be achieved by a linear discriminant analysis on volumes of the ventricular and intracranial subarachnoid spaces. We also find that healthy adults maintain a proportional relationship between these volumes