Role of neuroimaging in the diagnosis of hereditary cerebellar ataxias in childhood.

Hereditary ataxias are a heterogeneous group of neurodegenerative disorders, characterized by cerebellar ataxia as the main clinical feature, and a large spectrum of neurological-associated symptoms and possible multi-organ affection. Image-based approaches to hereditary ataxias in childhood have already been proposed. The aim of this review is to yield the main reports of neuroimaging patterns and diagnostic algorithms and compare them with the results from our study of 23 young patients addressed for ataxia, with subsequent genetic or metabolic diagnosis.

Mid-term clinical and angiographic results of cerebral aneurisms treated with matrix2(®) coils.

OBJECTIVE: To evaluate 1 year results of endovascular treatment (EVT) of intracranial aneurisms using Matrix second generation detachable coils (MSG(®)). PATIENTS AND METHODS: Between January and December 2006, 32 patients with 32 intracranial aneurisms were treated by coiling using MSG(®), with a minimum follow-up of 1 year. Data were acquired prospectively. Exclusion criteria were: permanent adjunctive device, less than 50% MSG(®) length, and additional bioactive or coated coils. All procedures were carried out in a single institution. Six months and 1 year follow-up were performed with magnetic resonance angiography and digital subtraction angiography, respectively. We assessed radiological and clinical results using the modified Raymond classification, a 3-level longitudinal grading scale (LGS), Glasgow outcome and Rankin scales. RESULTS: Thirteen (40.6%) male and 19 (59.4%) female underwent EVT using MSG(®) with a mean follow-up of 16.6 months. Ruptured aneurisms (75%) outnumbered unruptured. Immediate radiological results showed 15 complete occlusions (46.9%), 12 (37.5%) neck remnant, and five (15.6%) residual sac. In the mean time, six patients (18.7%) needed to be retreated due to insufficient initial packing or early recanalization. Using the LGS, a stable occlusion was observed in 40.7%, a progressive thrombosis in 25%, and 34.3% of the cases evolved unfavorably. Thirty-one patients had stable or improved clinical status, while one patient died from a thromboembolic event 1 month after retreatment (3.1% overall mortality). CONCLUSION: At 1 year follow-up, MSG(®) demonstrated similar angiographic results compared to Matrix first generation coils and didn't suggest advantage over platinum coils.

Association Between Vision and Brain Cortical Thickness in a Community-Dwelling Elderly Cohort.

Purpose: Visual impairment is a major cause of disability and impairment of cognitive function in older people. Brain structural changes associated with visual function impairment are not well understood. The objective of this study was to assess the association between visual function and cortical thickness in older adults. Methods: Participants were selected from the French population-based ESPRIT cohort of 2259 community-dwelling adults ≥65 years old enrolled between 1999 and 2001. We considered visual function and brain MRI images at the 12-year follow-up in participants who were right-handed and free of dementia and/or stroke, randomly selected from the whole cohort. High-resolution structural T1-weighted brain scans acquired with a 3-Tesla scanner. Regional reconstruction and segmentation involved using the FreeSurfer image-analysis suite. Results: A total of 215 participants were included (mean [SD] age 81.8 [3.7] years; 53.0% women): 30 (14.0%) had central vision loss and 185 (86.0%) normal central vision. Vision loss was associated with thinner cortical thickness in the right insula (within the lateral sulcus of the brain) as compared with the control group (mean thickness 2.38 [0.04] vs 2.50 [0.03] mm, 4.8% thinning, pcorrected= 0.04) after adjustment for age, sex, lifetime depression and cardiovascular disease. Conclusion: The present study describes a significant thinning of the right insular cortex in older adults with vision loss. The insula subserves a wide variety of functions in humans ranging from sensory and affective processing to high-level cognitive processing. Reduced insula thickness associated with vision loss may increase cognitive burden in the ageing brain.

Vessel wall MR imaging for the detection of intracranial inflammatory vasculopathies.

Intracranial vasculopathies are routinely investigated by lumen-based modalities such as magnetic resonance angiography (MRA), computed tomography angiography (CTA), and digital subtraction angiography (DSA). These techniques are useful to analyze the vessel lumen, allowing to detect vessel stenosis or occlusion. However, the primum movins of the disease, i.e., an abnormal thickening of the vessel wall, remains within the arterial wall. The vasculopathy can moreover be present without always narrowing the lumen or modifying its regularity. Hence, there is a need to detect directly and analyze vessel wall abnormalities. Development of 3D high-resolution black blood sequences for intracranial vessel wall MR imaging (VW-MRI) enabled routine clinical applications not only vasculitis, but also of intracranial atherosclerotic disease (ICAD), intracranial dissections, reversible intracranial dissections, reversible cerebral vasoconstriction syndrome (RCVS), Moyamoya disease, and intracranial aneurysms. This high-resolution intracranial VW- MRI approach is increasingly used on a clinical basis at many centers to solve diagnostic problems, especially in patients with ischemic stroke or intracranial hemorrhage. An expert consensus Guideline from the American Society of Neuroradiology provides recommendations for clinical implementation of intracranial vessel wall MRI. There are several technical aspects needed to be considered when implementing VW-MRI in intracranial vessels, including flow suppression, both in blood and cerebrospinal fluid (CSF), spatial resolution and signal-to-noise ratio (SNR). In this article, we review the technical aspects of VW-MRI, and recommend applications for vascular diseases including non-occlusive intracranial vasculopathies, Moyamoya disease, and identifying culprit plaques. We also give a focus on the utility of VW-MRI for determining stroke etiology in adults and in children and young adults.

Language reorganization after resection of low-grade gliomas: an fMRI task based connectivity study.

Few studies addressed the evolution of brain activity before and after brain tumor resection. Using a fMRI naming task, we evaluated possible underlying plasticity phenomena. Thirty-two patients with left low-grade gliomas (16 women; age = 38.6 ± 8.31 years) and 19 healthy controls (7 women; age = 42.4 ± 12.1) were included in the study. An overt picture-naming task (DO80) was performed pre and post (3 months) surgery, as well as within the MRI in a covert manner. Exams included an injected 3DT1, a T2FLAIR, a DTI and a GE-EPI (task) sequence. Activations maps were compared with picture naming score, FA and MD maps were estimated, a VLSM analysis was performed on tumor masks, and disconnectome maps were reconstructed. Pre-surgery, the left parahippocampal gyrus (LPH) was inversely associated with task performance. Increased pre-post surgery left lingual gyrus (LLG) activity was found related to decreased picture naming performance. The evolution of left lingual gyrus (LLG) activity was negatively associated with the evolution of picture naming performance. In controls, the LPH was functionally connected to the right precentral gyrus (RPCG) and slightly to the LLG. This was not clearly retrieved in the patient group. Preoperatively, the LLG was connected to the left planum temporale and to the right lingual gyrus. The same result was found for controls. Postoperatively, the LLG was only connected to the RPCG. No association was found between evolution of FA/MD and evolution of picture naming performance. There is not one unique pattern of pre- and postoperative plasticity concerning picture-naming performance in DLGG patients.

Endovascular treatment of 174 middle cerebral artery aneurysms: clinical outcome and radiologic results at long-term follow-up.

PURPOSE: To retrospectively evaluate the immediate safety and efficacy as well as the clinical outcome and long-term angiographic results of endovascular treatment (EVT) of middle cerebral artery (MCA) aneurysms. MATERIALS AND METHODS: This is a retrospective review of patients in whom coiling of MCA aneurysms was attempted over a 7-year period. Institutional review board approval and informed written consent were obtained. This study included 153 patients (90 women, 63 men; mean age, 49.5 years +/- 11.7 [standard deviation]) with 174 MCA aneurysms (71 unruptured, 103 ruptured). Complications of EVT, clinical outcome, and the results of either cerebral digital subtraction angiography (DSA) or magnetic resonance (MR) angiography were analyzed at initial, intermediate (6-18 months), and late (2-7 years) follow-up. RESULTS: Coiling was performed in 160 (92%) aneurysms in 141 patients. Periprocedural complications were observed in 31 (19.4%) procedures, including aneurysm perforations (n = 7, 4.4%) and thromboembolic events (n = 24, 15.0%). EVT induced permanent morbidity in eight (5.7%) patients, with severe neurologic impairment in three (2.1%) and two deaths (1.4%). Of 114 MCA aneurysms controlled by using DSA (n = 50) or MR angiography (n = 64) at 50 months +/- 14, 73 (64%) remained completely occluded, 31 (27.2%) recurred, and 12 (10.5%) major recurrences were retreated. A balloon remodeling technique allowed treatment of complex aneurysms (n = 63) but was associated with more recurrences in the long term (42.6%) than aneurysms treated without balloon assistance (16.4%; P = .016). CONCLUSION: EVT of MCA aneurysms was safe and long-term monitoring of patients showed a low rate of recurrence requiring retreatment. However, complex anatomy and long-term recurrences have to be addressed when considering EVT for MCA aneurysms.

Crossed aphasia elicited by intraoperative cortical and subcortical stimulation in awake patients.

OBJECT: Crossed aphasia (aphasia resulting from a right hemispheric lesion among right-handed patients) is rare. The authors describe for the first time transient crossed aphasia elicited by intraoperative electrostimulation of both cortex and white matter pathways in awake patients. METHODS: Three right-handed adults underwent surgery for a right-sided glioma. Because slight language disorders occurred during partial seizures or were identified on preoperative cognitive assessment, with right activations detected on language functional MR imaging in 1 patient, awake craniotomy was performed using intraoperative cortico-subcortical electrical functional mapping. RESULTS: Transient language disturbances were elicited by stimulating discrete cortical areas (inferior frontal gyrus and posterior part of the superior temporal gyrus) and white matter pathways (inferior frontooccipital fasciculus and arcuate fasciculus). A subtotal resection was achieved in all cases, according to functional boundaries. Postoperatively, 1 patient experienced a transient dysphasia, which resolved after speech rehabilitation, with no permanent deficit. CONCLUSIONS: These original findings highlight the possibility of finding crucial cortico-subcortical language networks in the right hemisphere in a subgroup of atypical right-handed patients. These findings provide new insights into the neural basis of language, by underlining the role of the right inferior occipitofrontal fasciculus in semantics and that of the right arcuate fasciculus in phonology, and by supporting the hypothesis of a mirror organization between the right and left hemispheres. The authors suggest that, in right-handed patients, if language disturbances are detected during seizures or on presurgical neuropsychological assessment, especially when right activations are observed on language functional MR imaging, awake craniotomy with intraoperative language mapping should be considered.

Endovascular treatment of symptomatic intracranial arterial stenosis: six-year experience in a single-center series of 42 consecutive patients with acute and mid-term results.

BACKGROUND: The limitations of the medical management of symptomatic intracranial arterial stenosis encourage the development of new therapeutic strategies such as intracranial stenting. OBJECTIVE: To report and analyze the results of a series of 42 patients treated with 3 different endovascular techniques: isolated angioplasty, balloon-expandable coronary stents, and the Wingspan self-expandable intracranial stent system. METHODS: Forty-two patients presenting with symptomatic intracranial arterial stenosis were treated with one of these techniques. Computed tomography angiography was performed 6 months after the procedure, and the clinical neurological statuses were categorized using the modified Rankin Scale and the National Institutes of Health Stroke Scale. RESULTS: A total of 42 lesions were treated: 9 with isolated angioplasty, 14 with balloon-expandable coronary stents, and 19 with Wingspan self-expandable intracranial stents. The mean patient age was 62.9 years, and the mean arterial diameter stenosis was 73.9%. Technical success was achieved in 97.6% of the patients. The overall incidence of procedural complications was 21.4%, and the postoperative permanent morbidity/mortality rate was 7.1%. There were 3 cases of in-stent thrombosis (1 fatal) and 5 cases of asymptomatic restenosis (11.9%), 3 in the isolated angioplasty group and 2 in the Wingspan self-expandable intracranial stent group (mean follow-up 20.4 months). The rate of restenosis was higher in the angioplasty group (33%) than in the coronary (0%) and Wingspan stent (10.5%) groups. CONCLUSION: Endovascular treatment of symptomatic intracranial stenosis has significant overall morbidity and mortality rates. Nevertheless, the very critical natural history of severe refractory lesions and the relatively favorable postoperative evolution suggest that it should be considered the first alternative strategy in cases in which medical therapy has failed.