Guy Cosnard, Jean-Louis Dietemann, Frederic Lecouvet - Imagerie de la colonne vertebrale et de la moelle epiniere - Elsevier Masson 3e edition 2017 448 pages - Format : 170 x 240 mm - ISBN : 9782294747236 - Prix format Livre : 89,00 € - Prix format Kindle eBook Epub : 62.99 € Descriptif L'analyse du rachis osteo-discal, de la moelle epiniere, des espaces rachidiens et des racines nerveuses s'est beaucoup enrichie ces dernieres annees, grâce aux progres constants de l'IRM souvent devenue l'examen de (...)

Persistent stapedial artery, one of the rare arterial congenital anomalies of the middle ear, is important to know due to its possible clinical repercussions. Ignoring its existence may lead to complications during surgery of the middle ear (notably hemorrhage). Exploration of the vascular malformation is rendered possible via high-definition computed tomography (CT) imaging of the petrous bones, which reveals the frequent bilaterality of this anatomical variation as well as the presence of associated anomalies. We report on two cases of persistent stapedial artery discovered during CT scan explorations.

À l’occasion de la revue de grandes entités pathologiques : apprendre à adapter sa technique selon l’indication et à rechercher des lésions multifocales. En pathologie malformative, hernie médullaire transdurale et diastématomyélie peuvent être de découverte tardive. En pathologie vasculaire, la fistule artérioveineuse durale à drainage veineux périmédullaire est la malformation vasculaire la plus fréquente et source d’erreur diagnostique. Lors de la découverte d’une cavité médullaire : savoir banaliser les distensions focales du canal épendymaire et détecter une syringomyélie tumorale. En pathologie tumorale : connaître les caractéristiques des tumeurs fréquentes : astrocytome, épendymome, hémangioblastome, cavernome. En pathologie inflammatoire : savoir indiquer un examen cérébral. Face à des images d’allure tumorale : penser pseudo-tumoral et en particulier aux granulomatoses.

Purpose: To assess the performance of parameters used in conventional magnetic resonance imaging (MRI), perfusion-weighted MR imaging (PWI) and visual texture analysis, alone and in combination, to differentiate a single brain metastasis (MET) from glioblastoma multiforme (GBM).Patients and methods: In a retrospective study of 50 patients (41 GBM and 14 MET) who underwent T2/FLAIR/T1(post-contrast) imaging and PWI, morphological (circularity, surface area), perfusion (rCBV in the ring-like tumor area, rCBV in the peritumoral area, percentage of signal intensity recovery at the end of first pass) and texture parameters in the peritumoral area were estimated. Statistical differences and performances were assessed using Wilcoxon's test and receiver operating characteristic curves, respectively. Multiparametric classification of tumors was performed using k-means clustering.Results: Significant statistical differences in circularity, surface area, rCBVs, percentage of signal intensity recovery and texture parameters (energy, entropy, homogeneity, correlation, inverse differential moment, sum average) were observed between MET and GBM (P < 0.05). Moderate-to-good classification performances were found with these parameters. Clustering based on rCBV and texture parameters (contrast, sum average) differentiated MET from GBM with a sensitivity of 92% and a specificity of 71%.Conclusion: Combining perfusion and visual texture parameters within a statistical classifier significantly improved the differentiation of a single brain MET and GBM. (C) 2011 Published by Elsevier Masson SAS.

Locked-in syndrome as an unusual complication of acute otitis media. Background: A 32-year-old woman developed altered consciousness two days after initial symptoms of acute otitis media, with purulent discharge from the right ear. She was quadriplegic, with spontaneous eye opening, mild neck stiffness, and lacking vestibular-ocular reflexes. Methodology: Upon admission, the patient was subjected to brain computed tomography (CT), magnetic resonance imaging (MRI), and lumbar puncture. Results: CT was consistent with pansinusitis, right middle ear otitis, mastoiditis, and sphenoiditis. No brainstem lesion was evident; brain MRI demonstrated ischemic and secondary hemorrhagic lesions in the pons and cerebral peduncles. The dura mater in the petroclival space was intensely inflamed, and likely responsible for reduced basilar arterial blood flow. Lumbar puncture yielded clear cerebrospinal fluid; gram stain examination was negative and culture remained sterile. Streptococcus pneumoniae and Haemophilus influenzae were cultured from the purulent ear discharge. Conclusion: The final diagnosis was locked-in syndrome consecutive to inflammatory changes compressing the basilar artery.

We present a short and comprehensive report of our 39-month experience using a 3.0 T intra-operative magnetic resonance imaging (ioMRI) neurosurgical-MR twin room, including a description of the problems encountered and the associated time-delays. Forty-seven problems were experienced during the 189 ioMRI procedures (two ioMRI were performed in five of the 184 surgical procedures) performed in the 39-month period, including a blocked transfer table, failure of anesthetic monitoring material, and specific MRI-related problems, such as head and coil positioning difficulties, artefacts, coil malfunctions and other technical difficulties. None of these problems prevented the ioMRI procedure from taking place or affected image interpretation, but they sometimes caused a significant delay. Fifteen (32%) of these problems occurred during the initial learning curve period. The mean duration of the ioMRI procedure was 75 min, which decreased slightly with experience, although an average waiting-for-access time of 24 min could not be avoided. These results illustrate that although performing ioMRI at 3.0 T with the dual room is a challenging procedure, it remains safe and feasible and associated with only minor dysfunctions while offering optimal image quality and standard surgical conditions.

Hemiballism-hemichorea is characterized by non-patterned and involuntary unilateral movements. It is a rare clinical sign unmasking type 2 diabetes mellitus, mostly in elderly patients. We report the clinical and neuroimaging findings of a patient admitted for hemiballism-hemichorea of the right upper limb, leading to the diagnosis of type 2 diabetes. We hereby describe clinical and neuroimaging findings. After initiation of treatment and restoration of euglycaemia, we note a complete remission of the initial neurological symptoms.

We present the case of a 35-year-old patient suffering from nasal obstruction and headache for 3 years. The patient was hospitalized for a recent and progressive decline of vision of the right eye associated with afferent pupillary deficit and inferior altitudinal hemianopsia. He was diagnosed with systemic sarcoidosis involving the central nervous system as illustrated by magnetic resonance imaging (MRI) scans showing different type diffuse lesions of meningo-encephalitis. Our case is characterized by severe cerebral pachyleptomeningeal lesions complicated by optic nerve compression and cervical spinal cord damage. MRI value of diagnosis for systemic neurosarcoidosis was supported by histological examination of a biopsy of the sphenoid sinus lesions that showed epithelioid granulomas presence without caseous necrosis. Thus, MRI of the brain and spinal cord is a powerful tool method in monitoring and diagnosing asymptomatic and symptomatic neurosarcoiodosis. MRI is also a powerful tool in monitoring the neurosarcoidosis during therapeutic treatments.

A 46-year-old woman presented with tetraplegia contrasting with a relatively preserved consciousness following aneurysmal subarachnoid hemorrhage (SAH). Multiple ischemic lesions were detected by magnetic resonance imaging (MRI), in the absence of vasospasm or signs of increased intracranial pressure. During the weeks before SAH, the patient had repeatedly used a nasal decongestant containing phenylephrine. After coiling of the aneurysm harboured by the right posterior cerebral artery, symptomatic vasospasm developed in the territory of the right middle cerebral artery and required aggressive therapy by intra-arterial infusion of milrinone followed by continuous intravenous administration. Follow-up MRI did not reveal new ischemic lesions. Echocardiography had demonstrated the presence of a patent foramen ovale. At 3 months follow-up, a major motor deficit persisted with akinetic mutism. The mechanisms of multiple early infarction following aneurysmal SAH are still debated, as vasospasm is usually not seen on the first imaging. Among precipitating factors of microvascular vasospasm, vasoactive substances like phenylephrine, may play a significant role.

superficial siderosis is characterized by the accumulation of hemosiderin all around the central nervous system. the cause is a chronic bleeding in the subarachnoid space, with preferential localisation around the cerebellum and the eighth cranial nerves that explains the typical clinical manifestations: cerebellar ataxia and sensorineural hearing deficits (1). the best diagnosis method is cerebral Mri which demonstrates the presence of a pathognomonic t2 or t2*-hyposignal rim at the brain surface. dural pathology represents the most frequent aetiology, followed by tumours and vascular malformations (2). However, in one third of the cases, aetiology remains elusive. Currently, no treatment is able to reduce the toxicity of hemosiderin. the only treatment is the eradication of the source of bleeding, to prevent detrimental evolution towards debilitating end-stage disease.