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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. [ABSTRACT FROM AUTHOR]

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<0.001).Conclusion: We concluded that extratemporal lobe epilepsy in general is not associated with diminished volumes in the studied subcortical structures, which contrasts with findings in temporal lobe epilepsy patients. Thus, both entities differ both cortically and subcortically. However, we found that small putamen volume was bilaterally associated with absent or rare generalised tonic-clonic seizures, implicating the putamen in the control of the most disabling seizure type, independent of the site of neocortical focus. [ABSTRACT FROM AUTHOR]

Behçet 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-Behçet disease and once introduced should be maintained for a prolonged period of time. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Progressive multifocal leucoencephalopathy (PML), a demyelinating disease caused by the JC virus (JCY), 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Gangliogliomas are tumors of mixed glial and neuronal phenotype that usually have a benign clinical course. Rare cases display anaplastic features at the time of first presentation or progress to anaplastic gliomas over extended times. We report on a ganglioglioma of the spinal cord that recurred as a malignant glioma one and a half years after resection. The initial neoplasm was composed of a mixture of well-differentiated ganglionic and astrocytic cells. The recurrent tumor was an anaplastic small-cell glioma. The sole unusual aspect in the initial neoplasm was an abundance of small vessels with calcified walls., which mimicked a vascular malformation. [ABSTRACT FROM AUTHOR]

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<0.0001). [ABSTRACT FROM AUTHOR]

Abstract We carried out MRI on 16 male and three female comatose patients, aged 2 days to 79 years, with suspected cortical ischaemia referred from our intensive care units. Using a head coil, and following standard imaging, including coronal fluid-attenuated inversion-recovery images, we performed diffusion-weighted imaging (DWI) using a whole-brain multislice singleshot echo-planar sequence with b 0 and 1000 s/mm²: 5-mm slices covering the whole brain, TR 7000 TE 106 ms, 128×128 pixels, field of view 250 mm, one excitation. Maps of apparent diffusion coefficients (ADC) were generated automatically. DWI showed cortical, basal ganglia and watershed-area high signal in all cases, associated with a decrease in ADC to 60-80% of normal. DWI showed lesions not seen (40%) or underestimated (40%) on conventional T2-weighted imaging. Within 24 h of the onset of symptoms, DWI showed changes not readily detectable on T2-weighted images. The cortical high signal on DWI and the ADC changes, suggesting severe ischaemia rather than oedema, was found in areas known to be affected by cortical laminar necrosis. Extension to the brain stem and white matter was associated with a higher likelihood of [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the potential of high quality computed tomographic angiography (CTA) to replace digital subtraction angiography (DSA) in cases of ruptured saccular aneurysms and perform early surgical clipping or coiling on the basis of CTA alone. In a prospective study, 100 patients with aneurysmal subarachnoid haemorrhage (SAH) diagnosed by computed tomography underwent CTA. CTA revealed a total of 118 aneurysms including all ruptured aneurysms. A decision of direct surgical clipping, endovascular coiling or therapeutic abstention was made in 89 cases (89%) on the basis of CTA alone. Sixty-one direct surgical procedures were performed after CTA. Twenty-six cases underwent DSA for immediate endovascular treatment of the ruptured aneurysm. In 11 cases (11%), a DSA was performed prior to the therapeutic decision because of unclear aneurysm. Four cases were not treated because of initial poor clinical grade. The surgical findings were compared with CTA data and were considered accurate in all but one case. All patients underwent postoperative DSA within 10 days after SAH. The sensitivity and the specificity of CTA for the detection of all aneurysms, as compared with postoperative DSA, were 95.1 and 100%, respectively. A total of six unruptured aneurysms were missedinitially, but were visible retrospectively on CTA in all but one case and were found in patients with multiple aneurysms in whom the ruptured aneurysm was detected by CTA. Current quality CTA allows reliable pretreatment planning for the majority of cases of aneurysmal subarachnoid haemorrhage and diminishes the pretreatment evaluation time critically. Complementary pretreatment DSA is required in situations where CTA characteristics of the ruptured aneurysm is unsatisfactory. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The aim of this study was to describe the various MRI features, in correlation to surgical and pathological findings, in patients who presented with pituitary apoplexy (PA). Eleven patients presenting with PA, were evaluated with various MR protocols including spin-echo (SE) T1-weighted sequences in 9 of 11 patients, post gadolinium SE T1-weighted sequences in only 8 of 11 patients, and with T2-weighted SE sequences in 2 of 11 patients. All patients had transsphenoidal pituitary surgery after MR studies. The severity of presenting symptoms ranged from headaches to coma. Ten patients had pituitary macroadenoma; one had a non-hemorrhagic metastatic lesion into a non-adenomatous pituitary gland. Of the 11 patients, one was studied at the acute stage of PA (1 day after onset), 9 at the subacute period (3-15 days after onset), and one at the late stage (5 months after onset). Images compatible with intratumoral hemorrhage were found in all macroadenomas, whereas the metastatic pituitary lesion did not show evidence of bleeding. All gadolinium-enhanced studies showed partial tumoral enhancement. The SE T2-weighted studies demonstrated areas of low and high signal intensities in keeping with the presence of blood degradation contents. Pituitary apoplexy present with different MR features, including hemorrhagic and non-hemorrhagic characteristics on T1-weighted images. Gadolinium-enhanced images do not provide complementary diagnostic information when the presence of blood is assessed on plain images. [ABSTRACT FROM AUTHOR]

A method of CT sagittal reconstruction, by which the exact topography and extent of tumors in the posterior fossa can be demonstrated, is described. [ABSTRACT FROM AUTHOR]

Behçet 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} α 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. White 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-Behçet disease and once introduced should be maintained for a prolonged period of time. [ABSTRACT FROM AUTHOR]

A letter to the editor which offers a case of patient with Raymond's syndrome which is the combination of the sixth cranial nerve palsy and contralateral hemiparesis is presented.