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Objects: Tectocerebellar dysraphism was first described by Padget and Lindenberg, together with occipital encephaloceles, cerebellar midline defects, tectal beaking, posterior kinked and displaced brainstem, and inverted cerebellum. We present a unique case of lipoencephalocele associated with tectocerebellar dysraphia and discuss the etiologies of both pathologies. The importance of the developmental comprehension of posterior fossa malformations is stressed. Case report: A 9-month-old girl in good health was referred for a huge occipital mass. On local examination, the patient had a rounded mass about 10×12cm in size, covered by alopecic skin, with a small eccentric dimple without any discharge. Magnetic resonance imaging revealed a lipoencephalocele with an intra- and an extracranial part, associated with tectocerebellar dysraphia with no aspect of inverted cerebellum as originally described in the tectocerebellar dysraphia. Resection of the extracranial part of the lipoma was performed for esthetic reasons. The intracranial part remained in situ. Conclusion: The association of lipoencephalocele and tectocerebellar dysraphia is extremely rare. The functional prognosis seems to be less severe for this combination than for the isolated tectocerebellar dysraphia. This association favors the dysraphic theory for the embryogenesis of the lipoma. It seems safe to restrict the surgery of this bizarre malformation to its external part

The four symptoms composing Gerstmann's syndrome were postulated to result from a common cognitive denominator (Grundstörung) by Gerstmann himself. He suggested that it is a disorder of the body schema restricted to the hand and fingers. The existence of a Grundstörung has since been contested. Here we suggest that a common psychoneurological factor does exist, but should be related to transformations of mental images rather than to the body schema. A patient (H.P.) was studied, who presented the four symptoms of Gerstmann's syndrome in the absence of any other neuropsychological disorders. MRI showed a focal ischaemic lesion, situated subcortically in the inferior part of the left angular gyrus and reaching the superior posterior region of T1. The cortical layers were spared and the lesion was seen to extend to the callosal fibres. On the basis of an extensive cognitive investigation, language, praxis, memory and intelligence disorders were excluded. The four remaining symptoms (finger agnosia, agraphia, right-left disorientation and dyscalculia) were investigated thoroughly with the aim of determining any characteristics that they might share. Detailed analyses of the tetrad showed that the impairment was consistently attributable to disorders of a spatial nature. Furthermore, cognitive tests necessitating mental rotation were equally shown to be impaired, confirming the essentially visuospatial origin of the disturbance. In the light of this report, the common cognitive denominator is hypothesized to be an impairment in mental manipulation of images and not in body schema.

Resume Objectifs La prise en charge des lesions traumatiques du plexus du brachial depend essentiellement de la localisation pre- (avulsion radiculaire) ou postganglionnaire (atteinte des troncs et faisceaux) des lesions. L'objectif de cette etude etait de determiner la valeur diagnostique et pronostique de l'IRM dans le bilan lesionnel du plexus brachial traumatique et de correler les resultats de l'imagerie aux donnees cliniques et electroneuromyographiques (ENMG) precoces et tardives. Materiel et methode Neuf patients presentant des lesions traumatiques du plexus brachial ont ete explores par IRM et ENMG a la phase aigue. Un controle a distance a egalement ete realise chez cinq patients. Le protocole IRM comprenait des sequences en FSE T2 et STIR. Les images ont ete interpretees independamment par deux radiologues seniors. Les resultats ont ensuite ete valides en concertation pluridisciplinaire entre chirurgiens, radiologues et neurologues afin de determiner la localisation exacte des lesions ainsi que le mecanisme en cause. L'apport et les limites de chaque technique ont egalement ete precises. Resultats Parmi les neuf patients, l'IRM etait jugee normale chez trois patients alors que l'ENMG montrait des lesions distales chez deux d'entre eux. Chez trois patients, les sequences STIR retrouvaient des hypersignaux etendus de C5 a T1 des troncs et des faisceaux avec persistance des anomalies de signal a trois mois chez un patient et regression partielle des anomalies chez les deux autres. Chez les trois derniers patients, les sequences 3DT2 montraient la presence d'avulsions radiculaires, en concordance avec les donnees de l'ENMG initiale. Conclusion L'IRM est l'examen de choix pour detecter les avulsions radiculaires. En revanche, l'IRM ne permet pas d'apprecier et de localiser les lesions tres distales du plexus contrairement a l'ENMG. La differenciation entre œdeme (atteinte reversible) et demyelinisation (atteinte irreversible) des lesions postganglionnaires necessite une IRM tardive ou des examens complementaires type ENMG.

Progressive multifocal leucoencephalopathy (PML), a demyelinating disease caused by the JC virus (JCV), occurs in immunosuppressed patients and carries a poor prognosis. A favourable outcome is reported in two patients with PML and dermatomyositis. Immunosuppressive drugs were stopped in patient 1 but could only be partially tapered in patient 2. The JCV-specific CD8+ T cell response was strong in patient 1 and weak in patient 2. Both were treated with cytosine-arabinoside, and patient 2 was also treated with mirtazapine, a 5HT2A receptor antagonist. Combination of these drugs might be helpful to treat HIV-negative patients with PML.

Brain aging affects an increasing segment of the population and the role of chronic cerebrovascular disease is considered to be one of the main parameters involved. For this purpose we compared retrospectively MRI data with digitized subtraction angiography (DSA) data in a group of 50 patients focusing onto the watershed area of the carotid artery vascular territories. In order to evaluate the presence of white matter lesions (WML) in the hemispheric watershed areas, coronal fluid-attenuated inversion-recovery or axial T2 weighted MRI images of patients with symptomatic cerebrovascular insufficiency areas were compared with the capillary phase of DSA studies in anterior-posterior projection. Presence of cerebrovascular occlusive disease was evaluated on DSA using North American symptomatic carotid endarterectomy trial criteria and including evaluation of collateral vascular supply. Pathological MRI findings in the region of the watershed territories correlated overall in 66% of cases with a defect or delayed filling on DSA. In the case of asymmetrical MRI findings, there was a pathological finding of the capillary phase in the watershed area in 92% of DSA studies. Hypoperfusion in the capillary phase of the watershed area as seen on DSA correlated with the stenosis degree of the concerned carotid artery. Our findings suggest that asymmetrical findings of WML in the watershed areas as seen on MRI are caused by hemodynamic effect and a differentiation between small vessel disease and a consequence of distant stenosis may be possible under such conditions.

Because of its large spectrum of clinical manifestations, diagnosis of cerebral venous thrombosis may be very difficult. Since appropriate treatment influences prognosis, early recognition of this condition is extremely important. We report a subarachnoid hemorrhage as a rare initial manifestation of cerebral venous thrombosis. A 58-year-old woman was admitted with severe headache of sudden onset, neck stiffness, dysarthria, and ataxia. Computed tomography scan showed a subarachnoid hemorrhage in the right posterior fossa. Magnetic resonance imaging coupled with magnetic resonance angiography revealed right transverse/sigmoid sinus thrombosis with hemorrhagic infarction of the right cerebellar hemisphere leading to a pseudotumoral appearance and displacing the fourth ventricle. Anticoagulant treatment resulted in rapid clinical recovery and in resolution of the radiological signs of infarction and of the subarachnoid and subdural hemorrhages.

PURPOSE: To evaluate eight different diagnostic criteria to help detect neoplastic invasion of laryngeal cartilage at computed tomography (CT). MATERIALS AND METHODS: In a prospective series, 111 patients with carcinoma of the larynx or hypopharynx underwent thin-section, contrast material-enhanced CT before total or partial laryngectomy. The following CT criteria were evaluated: extralaryngeal tumor, sclerosis, tumor adjacent to nonossified cartilage, serpiginous contour, erosion or lysis, obliteration of marrow space, cartilaginous blowout, and bowing. Histologic findings were correlated with findings on CT scans obtained at each level. RESULTS: Histologically, 122 of 412 cartilages were invaded. Depending on the diagnostic criteria and each specific cartilage, there was great variation in sensitivity (7%-83%) and specificity (40%-100%). Sclerosis was the most sensitive criteria in all cartilages but often corresponded to reactive inflammation in the thyroid cartilage. Extralaryngeal tumor and erosion or lysis yielded the highest specificity. Tumor adjacent to nonossified cartilage, serpiginous contour, and obliteration of marrow space were specific although not sensitive signs of invasion in the arytenoid and cricoid cartilage and were nonspecific in the thyroid cartilage. Blowout and bowing were not useful. Selection of the appropriate combination of criteria enabled an overall sensitivity of 91% (associated specificity, 68%) or an overall specificity of 79% (associated sensitivity, 82%). CONCLUSION: Detection of neoplastic cartilage invasion with CT greatly depended on the appropriate use of individual and combined CT criteria.

This report describes techniques and protocols implemented at the Geneva Canton University Hospitals (HUG) for the combination of various biomedical imaging modalities and sensors including electromagnetic tomography, to study, assess, and localize neurological (dys) function. The interest for this combination stems from the broad variety of information brought out by (functional) magnetic resonance imaging, magnetic resonance spectroscopy, computed tomography, single-photon emission tomography, positron emission tomography, and electromagnetic tomography. Combining these data allows morphology, metabolism, and function to be studied simultaneously, the complementary nature of the information from these modalities becoming evident when studying pathologies reflected by metabolic or electrophysiologic dysfunctions. Compared with other current multimodality approaches, the one at the HUG is totally compatible with both clinical and research protocols, and efficiently addresses the multidimensional registration and visualization issues. It also smoothly integrates electrophysiology and related data as fully featured modalities.

The corpus callosum is the largest white matter structure in the brain, consisting of 200-250 million contralateral axonal projections and the major commissural pathway connecting the hemispheres of the human brain. The pathology of the corpus callosum includes a wide variety of entities that arise from different causes such as congenital, inflammatory, tumoural, degenerative, infectious, metabolic, traumatic, vascular and toxic agents. The corpus callosum, or a specific part of it, can be affected selectively. Numerous pathologies of the corpus callosum are encountered during CT and MRI. The aim of this study is to facilitate a better understanding and thus treatment of the pathological entities of the corpus callosum by categorising them according to their causes and their manifestations in MR and CT imaging. Familiarity with its anatomy and pathology is important to the radiologist in order to recognise its disease at an early stage and help the clinician establish the optimal therapeutic approach.

Patient de sexe masculin âge de 22 ans sans antecedent particulier, qui decrit avoir presente a plusieurs reprises depuis environ 6 jours avant l’hospitalisation, des cephalees au niveau occipital puis holocephaliques. Les douleurs sont nonpulsatiles, sans phono-photophobie avec des nausees et soulagement transitoire apres vomissement, sans fievre, ni frisson, ni raideur nucale et sans lateralisation ; toute cette symptomatologie est precedee de douleurs abdominales. Le patient ne presentait ni d’apraxie ni aphasie, etait oriente dans le temps et dans l’espace. La stereognosie et la graphesthesie etaient dans la norme. Il n’y avait pas de signe de Lhermitte. L’equilibre et la demarche etaient normale. Parmi les facteurs de risques cardiovasculaires nous pouvons citer le tabagisme et la consommation d’alcool reguliere. Un bilan de la coagulation a ete demande qui etait dans la norme ainsi qu’un Doppler pour detection d’embole qui demontre la presence d’un foramen ovale permeable. Vu la persistance de la symptomatologie, un angio CT cerebral est realise en urgence. Le scanner cerebral montrait une stenose segmentaire et importante du tiers moyen du tronc basilaire et de la partie distale de l’artere vertebrale droite, sans lesion atheromateuse associee ni autre anomalie (fig. 1a) . Une resonance magnetique cerebrale et des arteres renales a ete realisee comme complement du bilan un mois plus tard. La resonance magnetique cerebrale realisee comportait les sequences morphologiques habituelles (FSE T2 axiale, SE T1 axiale, FLAIR coronale, diffusion axiale) et des sequences angiographiques 3DTOF du polygone de Willis et 3D des troncs supra-aortiques apres injection d’un bolus de produit de contraste. Les deux sequences angiographiques (avec et sans produit de contraste) montraient une disparition de la stenose du tronc basilaire et de l’artere vertebrale (fig. 1b) , constatees sur l’angio CT, ce qui parlait en faveur d’une migraine basilaire associee a un vasospasme sans lesion ischemique.

Among 504 cases of AIDS diagnosed between 1983 and 1990, there were 86 patients (17%) with toxoplasma encephalitis (TE). All were symptomatic at the time of diagnosis. General signs such as fever, neck stiffness, or headache were present in 87.2%, and 75.6% had focal signs. The primary means of diagnosis was computerized tomographic scanning, revealing 169 lesions of which 80% were immediately contrast-enhancing. All patients had IgG antibodies against Toxoplasma gondii either before (74 of 75 evaluable patients) or at the time of diagnosis of TE (73 of 75). Elevated antibody titers were present in 44% of evaluable patients, compared to 11% of patients with AIDS and other opportunistic infections. Initial treatment was pyrimethamine plus sulfonamides in 65 patients, and pyrimethamine plus clindamycin in 12 patients, with other combinations or no treatment accounting for the remainder. Life-table analysis of the time to discontinuation of treatment because of suspected side effects suggested that sulfadiazine was significantly more toxic, with 48% of patients experiencing an interruption in treatment after 30 days, than pyrimethamine (12%) or clindamycin (24%). The 30-day mortality rate was 12%, and median survival was 310 days after diagnosis, 530 in patients treated with zidovudine and 190 days in those not so treated. Of 82 evaluable patients, 16 relapsed once and 4 of these more than once. The risk of relapse was 27% 1 year after diagnosis of a first episode of TE.

Introduction: The objective of this study was to assess the feasibility and potential clinical applications of diffusion tensor imaging (DTI) and tractography in the normal and pathologic brachial plexus prospectively. Methods: Six asymptomatic volunteers and 12 patients with symptoms related to the brachial plexus underwent DTI on a 1.5T system in addition to the routine anatomic plexus imaging protocol. Maps of the apparent diffusion coefficient (ADC) and of fractional anisotropy (FA), as well as tractography of the brachial plexus were obtained. Images were evaluated by two experienced neuroradiologists in a prospective fashion. Three patients underwent surgery, and nine patients underwent conservative medical treatment. Results: Reconstructed DTI (17/18) were of good quality (one case could not be reconstructed due to artifacts). In all volunteers and in 11 patients, the roots and the trunks were clearly delineated with tractography. Mean FA and mean ADC values were as follows: 0.30 ± 0.079 and 1.70 ± 0.35mm2/s in normal fibers, 0.22 ± 0.04 and 1.49 ± 0.49mm2/s in benign neurogenic tumors, and 0.24 ± 0.08 and 1.51 ± 0.52mm2/s in malignant tumors, respectively. Although there was no statistically significant difference in FA and ADC values of normal fibers and fibers at the level of pathology, tractography revealed major differences regarding fiber architecture. In benign neurogenic tumors (n = 4), tractography revealed fiber displacement alone (n = 2) or fiber displacement and encasement by the tumor (n = 2), whereas in the malignant tumors, either fiber disruption/destruction with complete disorganization (n = 6) or fiber displacement (n = 1) were seen. In patients with fiber displacement alone, surgery confirmed the tractography findings, and excision was successful without sequelae. Conclusion: Our preliminary data suggest that DTI with tractography is feasible in a clinical routine setting. DTI may demonstrate normal tracts, tract displacement, deformation, infiltration, disruption, and disorganization of fibers due to tumors located within or along the brachial plexus, therefore, yielding additional information to the current standard anatomic imaging protocols

OBJECTIVE: To evaluate the prognostic accuracy of combining perfusion CT (PCT) and thrombolysis in brain ischemia (TIBI) ultrasonographic grade in the triage of stroke patients who will benefit from thrombolysis and in predicting the clinical outcome. METHODS: We conducted a prospective study of all consecutive stroke patients admitted to our hospital from March 2003 to July 2007, presenting with signs of acute stroke within the therapeutic window, who had undergone either intravenous or combined intravenous and intra-arterial thrombolysis. All patients were evaluated by a complete stroke CT protocol, transcranial color-coded duplex sonographic monitoring, follow-up imaging (CT or MRI) and clinical outcome at 3 months, as assessed by the modified Rankin scale (mRS). RESULTS: A total of 34 patients were included with a mean NIHSS on admission of 14.2. This study revealed that PCT had 95% sensitivity and 71% specificity in the evaluation of therapy benefit as well as 75% sensitivity and 39% specificity in predicting clinical outcome. The extent of ischemic tissue according to PCT and TIBI grade were significantly correlated (p2) in 18 patients. CONCLUSION: PCT was the most accurate predictor of both thrombolytic therapy benefit and clinical outcome. The TIBI score was useful for determining whether or not to perform intravenous therapy alone or as a combined therapy.

Major progress has recently been made in the neuro-imaging of stroke as a result of improvements in imaging hardware and software. Imaging may be based on either magnetic resonance imaging (MRI) or computed tomography (CT) techniques. Imaging should provide information on the entire vascular cervical and intracranial network, from the aortic arch to the circle of Willis. Equally, it should also give information on the viability of brain tissue and brain hemodynamics. CT has the advantage in the detection of acute hemorrhage whereas MRI offers more accurate pathophysiological information in the follow-up of patients.

Imaging of the trigeminal nerve requires a thorough understanding of its anatomy and function, clinical symptoms related to malfunction, and its key pathologies. Because of the nerve's long course from the brainstem nuclei to the peripheral branches, MR imaging and CT studies have to cover a large anatomic area while providing high-resolution images. Although MR imaging has almost completely replaced CT as the diagnostic modality of choice for investigating trigeminal neuropathy, CT still plays a role in the assessment of skull base foramina and facial skeleton. In this article, the clinical, radiologic, and pathologic features of the most common conditions causing trigeminal nerve dysfunction at each specific anatomic level are discussed.

Diffusion tensor imaging (DTI) can visualize the white matter tracts in vivo. The aim of this study was to assess the clinical utility of DTI in patients with diseases of the spinal cord. Fourteen subjects underwent magnetic resonance imaging of the spine at 1.5 T. Preliminary diagnosis of the patients suggested traumatic, tumorous, ischemic or inflammatory lesions of the spinal cord. In addition to T2-weighted images, DTI was performed with the gradients in 30 orthogonal directions. Maps of the apparent diffusion coefficient and of fractional anisotropy were reconstructed. Diffusion tensor imaging showed a clear displacement and deformation of the white matter tracts at the level of the pathological lesions in the spinal cord. This capability of diffusion tensor imaging to reliably display secondary alterations to the white matter tracts caused by the primary lesion has the potential to be of great utility for treatment planning and follow-up.

This technical note demonstrates the relevance of the isotropic 3D T2 turbo-spin-echo (TSE) sequence with short-term inversion recovery (STIR) and variable flip angle RF excitations (SPACE: Sampling Perfection with Application optimized Contrasts using different flip angle Evolutions) for high-resolution brachial plexus imaging. The sequence was used in 11 patients in the diagnosis of brachial plexus pathologies involving primary and secondary tumors, and in six volunteers. We show that 3D STIR imaging is not only a reliable alternative to 2D STIR imaging, but it also better evaluates the anatomy, nerve site compression and pathology of the plexus, especially to depict space-occupying tumors along its course. Finally, due to its appropriate contrast we describe how 3D-STIR can be used as a high-resolution mask to be fused with fraction of anisotropy (FA) maps calculated from diffusion tensor imaging (DTI) data of the plexus.

To report a retrospective series of 84 cerebral developmental venous anomalies (DVAs), focusing on associated parenchymal abnormalities within the drainage territory of the DVA. DVAs were identified during routine diagnostic radiological work-up based on magnetic resonance imaging (MRI) (60 cases), computed tomography (CT) (62 cases) or both (36 cases). Regional parenchymal modifications within the drainage territory of the DVA, such as cortical or subcortical atrophy, white matter density or signal alterations, dystrophic calcifications, presence of haemorrhage or a cavernous-like vascular malformation (CVM), were noted. A stenosis of the collecting vein of the DVA was also sought for. Brain abnormalities within the drainage territory of a DVA were encountered in 65.4% of the cases. Locoregional brain atrophy occurred in 29.7% of the cases, followed by white matter lesions in 28.3% of MRI investigations and 19.3% of CT investigations, CVMs in 13.3% of MRI investigations and dystrophic calcification in 9.6% of CT investigations. An intracranial haemorrhage possibly related to a DVA occurred in 2.4% cases, and a stenosis on the collecting vein was documented in 13.1% of cases. Parenchymal abnormalities were identified for all DVA sizes. Brain parenchymal abnormalities were associated with DVAs in close to two thirds of the cases evaluated. These abnormalities are thought to occur secondarily, likely during post-natal life, as a result of chronic venous hypertension. Outflow obstruction, progressive thickening of the walls of the DVA and their morphological organization into a venous convergence zone are thought to contribute to the development of venous hypertension in DVA.

Summary: Purpose: Clinically silent lesions localized in the splenium of the corpus callosum (SCC) are a rare finding in the magnetic resonance imaging (MRI) of patients receiving antiepileptic drugs (AEDs). They are usually of benign character but may induce unnecessary complementary examinations if their nature is unrecognized. So far, 22 cases have been described in the literature, for which different etiologies have been proposed. We describe two further cases and discuss the probable lesion etiology. Methods: We report two cases including a 25-year-old male patient and a 12-year-old female patient with a transient SCC lesion discovered in the context of a presurgical epilepsy evaluation. Results: Comprehensive MRIs, including diffusion tensor imaging–based fiber tracking of the lesion, revealed a cytotoxic edema not disrupting neuronal fibers. Serum arginine vasopressin (AVP) measurements revealed an altered secretion during the acute phase in one patient. Conclusions: On the basis of our results, we hypothesize that the lesion consists of a cytotoxic edema, possibly induced by abrupt AED concentration changes and associated to alterations of AVP secretion.

Summary: Purpose: The exact anatomic and neurophysiologic correlates of idiopathic generalized epilepsy (IGE) in humans are still not well understood, although the thalamus has frequently been invoked as the crucial structure in the generation of primary generalized seizures. The few in vivo magnetic resonance (MR)-based studies in IGE patients suggest an altered cortical/subcortical gray matter ratio, but with no evidence of structural alterations of the thalamus. In this study, we sought to determine the volumes of the other subcortical structures. Methods: The volumes of the caudate nucleus, putamen, pallidum as well as the thalamus were each determined in both hemispheres in 11 patients with various IGE syndromes, normalized for whole-brain volumes and then compared with 15 age-matched controls. Results: No differences were noted in thalamic volumes, confirming previous reports. However, smaller subcortical volumes were noted in the IGE patients (p < 0.009), mainly due to smaller putamen bilaterally (p ≤ 0.015). Conclusions: It is speculated that the presence of discrete frontal dysfunction, as noted in neuropsychological studies in IGE patients, indirectly supports our results because the putamen projects predominantly to the frontal cortex. Larger studies with more homogeneous patient populations are needed to determine the robustness of these findings and whether they are specific for particular IGE syndromes. Ke yW ords: MRI—Idiopathic generalized epilepsy—Volumetry—Human—Caudate nucleus— Thalamus—Pallidum—Putamen—Striatum—Basal ganglia.

Behcet disease is a chronic relapsing inflammatory condition, predominantly affecting young adults, characterised by recurrent bipolar aphtae and systemic manifestations for which tumour necrosis factor (TNF) alpha blockade has recently emerged as an effective treatment. We report the case of a patient presenting with mucocutaneous and ocular manifestations who in the course of his disease developed CNS parenchymal involvement. While being treated with pulsed cyclophosphamide and corticosteroids, he suffered a relapse of his CNS involvement that was efficaciously controlled by infliximab. No disease activity was observed during a full year of TNF blockade, associated with azathioprine, colchicine, and corticosteroids. However, 7 months after the last administration of infliximab and still under immunosuppressant agents, CNS lesions recurred. Infliximab was successfully reintroduced and since continued with no side effects. The sequence of events observed in this patient suggests that TNF blockade is efficacious in suppressing neuro-Behcet disease and once introduced should be maintained for a prolonged period of time.

CASE OF THE MONTH: ABSTRACT FEBRUARY 2004 COM. A 44-year old man presented with a 2-year history of epistaxis and a nodular lesion in the nasopharyngeal mucosa. Neuroimaging revealed a midline nasopharyngeal tumor extending through the skull base to the clivus. Following surgical resection, histological studies showed a paraganglioma, a tumor with a typical nesting pattern, abundant capillary network, and strong immunoreactivity for neuroendocrine markers. Paragangliomas of the head and neck are rare tumors, which may come to the neuropathologist's attention because of their propensity for intracranial spread. In particular, paragangliomas located in the nasopharynx may generate diagnostic difficulties, as they appear to have no connection with major paraganglia in the region. Morphologic criteria do not allow distinguishing between benign and malignant forms.

Background: Evidence from previous volumetric magnetic resonance studies has revealed that patients with chronic temporal lobe epilepsy show atrophy of distinct subcortical nuclei, predominantly ipsilateral to the focus side. We were interested to find out if there is also selective subcortical atrophy in patients suffering from long standing extratemporal lobe epilepsy. Methods: Thirty one patients in whom pre-surgical evaluation unambiguously localised an extratemporal focus were included in this study. Using high resolution magnetic resonance imaging, the volumes of the caudate nuclei, putamen, pallidum, and thalamus were measured bilaterally in both hemispheres and compared with measurements obtained in 15 healthy volunteers. Results: No significant difference in volumes was found between the two subject groups, or in any subgroup of extratemporal lobe epilepsy patients, nor was there any relation to clinical variables such as age of onset, overall seizure frequency, or disease duration. However, patients who had no or only rare generalised tonic–clonic seizures seemed to differ from the other patients and controls in that they had smaller putamen volumes bilaterally (p

Normal aging, leukoaraiosis (LA) and vascular disease particularly involve the human frontal lobes. We decided to investigate a population of elderly patients referred for neuroimaging because of progressive minor cognitive deficits but no dementia. They underwent conventional Magnetic resonance imaging (MRI) using axial T1 and T2-weighted imaging as well as coronal FLAIR sequences in addition to the axial diffusion-weighted MRI. MRI allowed us to differentiate patients with leukoaraïosis (LA+) from those without it (LA-) and mapping of the apparent diffusion coefficient (ADC) to investigate local tissular water motion. We observed an increase in the ADC in all investigated patients with increasing age (r=0.326, p=0.002). This increase was observed in both patients groups (LA+ and LA-). In addition, the LA+ group had significant higher ADC values than the LA- group after controlling for age (p

Pallidal hyperintensity at magnetic resonance imaging (MRI) correlates to blood manganese (Mn) levels and parkinsonian signs in patients with cirrhosis. Similarly, metabolite changes in the basal ganglia (BG) at proton spectroscopy are related to these neurological signs. The evolution of these abnormalities after liver transplantation (OLT) is incompletely described. We evaluated 14 unselected consecutive patients with cirrhosis (minimal hepatic encephalopathy [HE] n=8, no HE n=6) before and 4 months after successful OLT for the evolution of parkinsonism using a validated scale (the United Parkinson's Disease Rating Scale, or UPDRS). Pallidal intensity at MRI, spectroscopic changes in the BG at magnetic resonance spectroscopy (MRS), and whole blood manganese concentrations were measured. After OLT in patients with preoperative minimal HE, the UPDRS scores improved, but mild parkinsonism persisted (16.1+/-3.6 to 6.2+/-4.8, P

A 74-year old man presented with horizontal diplopia of sudden onset, worsened by directing gaze to the left. His past medical history included arterial hypertension treated with an angiotensin conversion enzyme inhibitor, a 60pack-per-year smoking history and moderate alcohol consumption. Neurological examination showed moderate left VIth nerve paresis and slight paresis of the right arm and leg. Both spontaneous and voluntary facial movements were normal. Deep tendon reflexes were normal and symmetric. Cutaneous plantar response was flexor on both sides. There was no ataxia or sensory deficit. Gait was unremarkable. Laboratory examinations were normal except for slightly raised liver enzymes. Magnetic resonance imaging, performed 2 days after the onset of symptoms, showed a lesion in the left caudal ventral paramedian pons (Fig. 1a, b). Magnetic resonance angiography as well as extraand intracranial ultrasound with Doppler examination did not reveal any hemodynamically significant arterial stenosis. Heart rhythm remained regular during 24-h monitoring in the stroke unit. The patient was not handicapped by the slight hemiparesis; diplopia resolved partially over several days. Acetylsalicylic acid was introduced.

Purpose: Neurological impairment, mental dysfunction, and brain imaging changes caused by severe hypoxia have been described by several authors. However, the occurrence of transitory, long lasting, or permanent brain damage has been debated. Although climbing to 8000 m is reserved to a small number of climbers, there are hundreds of lowlanders spending relatively short holidays climbing peaks up to 6000 m in the Andes or in the Himalayas. They are usually not well acclimated and often suffer from acute mountain sickness (AMS). The aim of this study was to examine the effect of a single high altitude exposure on the changes in brain MRI and neuropsychological testing in climbers. Methods: Brain MRI, medical history, and a battery of neuropsychological tests were obtained in eight male climbers between 31 and 48 yr of age a few days before and between 5 and 10 d after returning to sea level following ascent to altitudes of over 6000 m without oxygen. Results: The mean AMS symptom score recorded at 5500 m was three in all climbers, headache being the predominant symptom. Conclusion: We did not observe the changes in brain imaging and in neuropsychological testing observed by other authors. The residual central nervous system impairment following return from high altitude was not observed in our study, and the good results in neuropsychological testing were well correlated with the unchanged brain MRI imaging.

We present a new approach for non-invasive localization of focal epileptogenic discharges in patients considered for surgical treatment. EEG-triggered functional MR imaging (fMRI) and 3D EEG source localization were combined to map the primary electrical source with high spatial resolution. The method is illustrated by the case of a patient with medically intractable frontal lobe epilepsy. EEG obtained in the MRI system allowed triggering of the fMRI acquisition by the patient's habitual epileptogenic discharges. fMRI revealed multiple areas of signal enhancement. Three-dimensional EEG source localization identified the same active areas and provided evidence of onset in the left frontal lobe. Subsequent electrocorticography from subdural electrodes confirmed spike and seizure onset over this region. This approach, i.e. the combination of EEG-triggered fMRI and 3D EEG source analysis, represents a promising additional tool for presurgical epilepsy evaluation allowing precise non-invasive identification of the epileptic foci.

High-dose irradiation is an effective treatment for tumors in the head and neck. Radiation-induced complications are uncommon but may result in chronic, progressive symptoms months or years after therapy. In 19 (1%) of 1,950 patients who underwent successful high-dose irradiation of head and neck tumors over a 5-year period, delayed radiation-induced changes were documented with imaging. These changes can be categorized as soft-tissue, bone, and cartilage necrosis; fibrosis leading to functional disorders; arteriopathy; central nervous system reactions, delayed myelopathy, and cranial nerve palsies; and the development of meningiomas. Radiologic features of radiation-induced soft-tissue, bone, and cartilage necrosis include inflammatory swelling adjacent to the area of involvement; deep gas-containing ulcerations; sclerotic appearance of the involved cartilages; fragmentation and sloughing of necrotic bone or cartilage; and abscess and fistula formation. Masticator muscle fibrosis appears as an area of diffusely increased signal intensity on T2-weighted images and of enhancement on postcontrast T1-weighted images. Radiation arteriopathy may manifest as occlusion, subocclusive sclerotic or atheromatous plaque, localized mural thrombus, aneurysm, or, rarely, spontaneous rupture. In central nervous system reactions, imaging findings include demyelination foci in the white matter, focal radiation necrosis, and severe brain atrophy. Radiation-induced meningiomas display the same imaging features as non-radiation-induced meningiomas at computed tomography, magnetic resonance imaging, and angiography, although follow-up examinations may reveal their more aggressive biologic behavior. Knowledge of the radiologic appearance of radiation-induced changes may prevent misinterpretations and facilitate treatment.

A 45-year-old woman had complex partial seizures for 25 years with pharmacoresistance for 2 years. EEG showed right temporal epileptiform discharges. MRI revealed atrophy of the right temporal parenchyma (figure, A) herniating toward the pterygomaxillary fossa and the sphenoidal sinus (figure, C). CT demonstrated the bone …

Article abstract— Background: Various structural and functional changes, such as focal edema, blood flow, and metabolism, occur in the cerebral cortex after focal status epilepticus. These changes can be assessed noninvasively by means of MRI techniques, such as fluid-attenuated inversion recovery (FLAIR), EEG-triggered functional MRI (EEG-fMRI), and proton MR spectroscopy (MRS). Methods: The authors report on a 40-year-old patient with nonlesional partial epilepsy in the left posterior quadrant in whom these MRI techniques were applied in an active seizure focus and repeated during a follow-up of 1 year. Results: FLAIR imaging taken at the time of status epilepticus showed a signal hyperintensity in the occipital region. 1 H-MRS of this cortical region showed elevated lactate, decreased N -acetylaspartate (NAA), and elevated choline (Cho). In the same region, EEG-fMRI revealed an area of signal enhancement. After seizure control, recovery of lactate and Cho was observed, whereas the NAA level remained reduced. The structural abnormality demonstrated on FLAIR disappeared within 3 months. Conclusions: Repetitive MRI with sensitive sequences during clinically critical periods may disclose the structural correlate in a previously nonlesional epilepsy case. Corresponding to the clinical evolution, reversible and irreversible focally abnormal metabolism can be determined with 1 H-MRS, reflecting both increased neuronal activity and neuronal damage.

The authors present a patient in whom electrical cortical stimulation of the posterior temporal cortex induced speech arrest, comprehension deficits, and other language-related impairments. This area was ultimately resected because of persistence of a severe seizure disorder. No postoperative aphasia was observed despite the cortical stimulation results, and the patient is since seizure free. These findings question the well-established principle that corticography directly reflects local cortical functions in all patients.