Language development at 2 years is correlated to brain microstructure in the left superior temporal gyrus at term equivalent age: a diffusion tensor imaging study.

This study aims at testing the hypothesis that neurodevelopmental abilities at age 2 years are related with local brain microstructure of preterm infants at term equivalent age. Forty-one preterm infants underwent brain MRI with diffusion tensor imaging sequences to measure mean diffusivity (MD), fractional anisotropy (FA), longitudinal and transverse diffusivity (λ// and λ[perpendicular]) at term equivalent age. Neurodevelopment was assessed at 2 years corrected age using the Bayley III scale. A voxel-based analysis approach, statistical parametric mapping (SPM8), was used to correlate changes of the Bayley III scores with the regional distribution of MD, FA, λ// and λ[perpendicular]. We found that language abilities are negatively correlated to MD, λ// and λ[perpendicular] in the left superior temporal gyrus in preterm infants. These findings suggest that higher MD, λ// and λ[perpendicular] values at term-equivalent age in the left superior temporal gyrus are associated with poorer language scores in later childhood. Consequently, it highlights the key role of the left superior temporal gyrus for the development of language abilities in children. Further studies are needed to assess on an individual basis and on the long term the prognostic value of brain DTI at term equivalent age for the development of language.

Nonlinear microstructural changes in the right superior temporal sulcus and lateral occipitotemporal gyrus between 35 and 43 weeks in the preterm brain.

Using diffusion tensor imaging (DTI), we explored microstructural brain maturation in a population of 65 preterm neonates who underwent magnetic resonance imaging between 35 and 43 weeks of corrected gestational age. A voxel-based analysis approach, statistical parametric mapping (SPM8), was used to evidence the nonlinear changes with the corrected gestational age in the regional distribution of mean diffusivity (MD), fractional anisotropy (FA), longitudinal and transverse diffusivities (λ//and λ⊥). We found that FA changes nonlinearly with age around the right superior temporal sulcus and in the right lateral occipitotemporal gyrus, with FA decrease between 34 and 39 weeks followed by FA increase from 40 weeks to 43 weeks. Considering the key role of these brain areas in verbal and non-verbal communicative behaviors, the effect of these microstructural changes in terms of early social network functional maturation needs to be assessed by joint functional and anatomical studies.

Brain regional glucose uptake changes in isolated cerebellar cortical dysplasia: qualitative assessment using coregistrated FDG-PET/MRI.

We aimed to assess brain regional glucose uptake (rGlcU) changes in children with isolated cerebellar cortical dysplasia (CCD) using 18-fluoro-deoxy-glucose positron emission tomography (FDG-PET). Six children aged 9 months to 11 years at the time of diagnosis, carrying isolated CCD (with no other associated posterior fossa or supratentorial malformation) underwent a brain FDG-PET and a subsequent 3DT1-weighted MRI for coregistration. The MRIs acquired previously at the time of diagnosis were reviewed to record the cerebellar dysplastic features and classify the patients as having minor, moderate, or severe CCD. The individual rGlcU was assessed qualitatively on coregistrated FDG maps. Clinical data from birth, including neurological and neuropsychological (verbal and motor skills) disturbances, were recorded. We found rGlcU changes within the cerebellum of four patients matching with the location and extent of structural abnormalities: hypometabolism in three patients with severe CCD involving the vermis and both cerebellar hemispheres and focal hypermetabolism in one patient with moderate CCD associated with a nodular heterotopic gray matter. No obvious rGlcU changes were found in the two patients with minor CCD involving the vermis only. Supratentorial rGlcU changes found commonly involved the basal ganglia bilaterally. Coregistrated FDG-PET/MRI technique is useful in detecting cerebellar cell dysfunction associated with isolated CCD. Our results enhance the need for multimodal and quantitative studies to better evaluate local and remote functional disturbances caused by CCD.

Structural asymmetries in motor and language networks in a population of healthy preterm neonates at term equivalent age: a diffusion tensor imaging and probabilistic tractography study.

In this MRI study, we aimed to provide new in vivo structural markers of asymmetry in motor and language networks in a population of healthy preterm neonates scanned at term equivalent age. Using diffusion tensor imaging and probabilistic tractography, we showed that, besides volume and microstructural asymmetries in the parieto-temporal part of the superior longitudinal fasciculus (SLF) and a trend towards microstructural asymmetry in the corticospinal tract (CST), volume asymmetry in the motor part of the superior thalamic radiations (STR) and a trend towards volume asymmetry in the CST are already present in the neonatal period. No asymmetry was found in the sensory part of the STR, the anterior thalamic radiations (ATR), and posterior thalamic radiations (PTR) neither in the fronto-parietal part of the SLF. These results suggest that structural asymmetries in the motor and language networks are present in healthy preterm neonates at term equivalent age, well before the development of speech and hand preference.

Selective embolization of unruptured intracranial aneurysms is associated with low retreatment rate.

INTRODUCTION: To report long-term imaging findings of 101 patients with 129 unruptured intracranial aneurysms (UIA) treated by embolization. METHODS: A retrospective review of our prospectively maintained database identified all patients with an UIA treated by embolization with coils only and with a minimal 12-month imaging follow-up. The clinical charts, procedural data, and angiographic results were reviewed. RESULTS: Between March 2004 and June 2009, 101 patients with 129 UIA were identified (71 women/30 men, mean age = 51.4 years). Ninety-four aneurysms (73%) were large (10-25 mm), and 35 (27%) were small (<10 mm). Aneurysms mean size was 10.7 mm (median, 9 mm; range 3-22 mm); 87 UIA (67.5%) had a small neck (<4 mm or neck/sac ratio < 0.7), and 42 (32.5%) had a wide neck (> or =4 mm or neck/sac ratio > or = 0.7). Selective coiling with bare/coated coils was performed in 125 cases and four cases, respectively. The balloon-assisted technique was used in 47 cases (36.4%). Only one patient experienced a symptomatic complication (thromboembolism) and kept a slight hemiparesis. Immediate results included 77 complete occlusions (59.7%), 45 neck remnants (34.9%), and 7 incomplete occlusions (5.4%). Mean imaging follow-up of 32 months showed 104 stable occlusions (80.6%), 12 further thrombosis (9.3%), 7 major recanalizations (5.4%), and 6 minor recanalizations (4.7%). Retreatment was required in seven wide-necked and/or large aneurysms including four treated with coated coils. No bleeding occurred during follow-up. CONCLUSION: Selective embolization of UIA is associated with stable long-term anatomical results and low retreatment rate.

Relationship Between White Matter Abnormalities and Neuropsychological Measures in Children With ADHD.

Objective: Using Diffusion Tensor Imaging (DTI), to investigate microstructural white matter differences between ADHD and typically developing children (TDC), and their association with inhibition and working memory performance usually impaired in ADHD. Method: Fractional anisotropy (FA) and mean diffusivity (MD) were estimated in 36 noncomorbid children with a Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.; DSM-IV-TR) diagnosis of combined type ADHD and 20 TDC. Correlations between FA/MD and Stop Signal Task and N-Back performance parameters were computed. Results: Working memory performance was significantly associated with MD in the superior longitudinal fasciculus (SLF) and the cingulum in the ADHD group. No between-group differences in FA/MD reached significance, after controlling for between-group head motion differences. Conclusion: The association between white matter integrity in the cingulum and the SLF and working memory performance confirms previous studies. Our results also show that when critical conditions are controlled (age, comorbidity, head motion), no ADHD-related structural abnormality (FA/MD) are observed, in line with prior suggestions.

Central diabetes insipidus and pituitary stalk thickening in adults: distinction of neoplastic from non-neoplastic lesions.

CONTEXT: Association of central diabetes insipidus (CDI) and pituitary stalk thickening (PST) may have several etiologies (including malignancies) and differential diagnosis remains often difficult. OBJECTIVE: The purpose of this study was to identify which clinical, biochemical or radiological features could help clinicians to make an etiological diagnosis, especially distinguishing neoplastic from non-neoplastic pituitary stalk lesions. DESIGNS AND METHODS: We retrospectively analyzed clinical, biochemical, radiological and histological data of 38 adult patients diagnosed with CDI and PST of proven etiology. RESULTS: Of the 38 pituitary stalk lesions included, 11 (29%) were neoplastic. A histopathological diagnosis was obtained in 22/38 (58%) patients. The three most frequently observed etiologies of PST were neuroinfundibulitis (34%), germinoma (21%) and histiocytosis (18%). Pituitary stalk thickness was larger for neoplastic lesions, particularly germinomas. Male gender and a very young age were statistically associated with a risk of germinoma. At least one anterior pituitary deficit was observed in nearly 60% of patients. Patients with neoplastic PST were more affected by multiple anterior pituitary dysfunction than patients with benign PST. A high serum prolactin level was individually the best predictor of a neoplastic origin (90% sensitivity and 60% specificity for a serum prolactin level 1.27-fold above the normal upper limit (ULN)). CONCLUSION: We confirm a relatively high risk of malignancy in adult patients presenting with the association of CDI and PST. Young age, male gender, a very large thickening of the stalk, multiple anterior pituitary deficits and prolactin above 1.3× ULN increase the likelihood of a neoplastic origin.

Clinical, radiological and molecular characterization of intramedullary astrocytomas.

Intramedullary astrocytomas (IMAs) are rare tumors, and few studies specific to the molecular alterations of IMAs have been performed. Recently, KIAA1549-BRAF fusions and the H3F3A p.K27M mutation have been described in low-grade (LG) and high-grade (HG) IMAs, respectively. In the present study, we collected clinico-radiological data and performed targeted next-generation sequencing for 61 IMAs (26 grade I pilocytic, 17 grade II diffuse, 3 LG, 3 grade III and 12 grade IV) to identify KIAA1549-BRAF fusions and mutations in 33 genes commonly implicated in gliomas and the 1p/19q regions. One hundred seventeen brain astrocytomas were analyzed for comparison. While we did not observe a difference in clinico-radiological features between LG and HG IMAs, we observed significantly different overall survival (OS) and event-free survival (EFS). Multivariate analysis showed that the tumor grade was associated with better OS while EFS was strongly impacted by tumor grade and surgery, with higher rates of disease progression in cases in which only biopsy could be performed. For LG IMAs, EFS was only impacted by surgery and not by grade. The most common mutations found in IMAs involved TP53, H3F3A p.K27M and ATRX. As in the brain, grade I pilocytic IMAs frequently harbored KIAA1549-BRAF fusions but with different fusion types. Non-canonical IDH mutations were observed in only 2 grade II diffuse IMAs. No EGFR or TERT promoter alterations were found in IDH wild-type grade II diffuse IMAs. These latter tumors seem to have a good prognosis, and only 2 cases underwent anaplastic evolution. All of the HG IMAs presented at least one molecular alteration, with the most frequent one being the H3F3A p.K27M mutation. The H3F3A p.K27M mutation showed significant associations with OS and EFS after multivariate analysis. This study emphasizes that IMAs have distinct clinico-radiological, natural evolution and molecular landscapes from brain astrocytomas.

Stenting is improving and stabilizing anatomical results of coiled intracranial aneurysms.

INTRODUCTION: Stent-assisted coiling (SAC) is an alternative to surgical clipping for the treatment of wide-necked intracranial aneurysms (IA). However, little information is available concerning the long-term results of this treatment. The aim of this study was to report the long-term clinical and anatomical findings in 32 patients with 34 wide-necked IA treated by SAC. METHODS: A retrospective review of our prospectively maintained database identified all patients followed up for wide-necked IA treated by SAC. The clinical charts, procedural data, and angiographic results were reviewed. RESULTS: Thirty-two patients with 34 IA were identified including 25 asymptomatic patients, four with cranial nerve palsies, two with a subarachnoid hemorrhage, and one with transient ischemic attacks. Mean aneurysm size was 10.2 mm (range 3.5 to 26 mm). Embolization was successful in all patients and no procedure-related neurological morbidity or mortality was observed. Immediate anatomical results included nine complete occlusions (26.5%), two neck remnants (6%), and 23 incomplete occlusions (67.5%). Mean imaging follow-up of 20 months showed 18 further thrombosis (53%) and 16 stable results (47%). Finally, 27 aneurysms were completely occluded (79%), three had a neck remnant (9%), and four were incompletely occluded (12%). Asymptomatic and nonsignificant in-stent stenosis occurred in seven patients (22%). CONCLUSIONS: SAC is safe and effective for the treatment of wide-necked IA. Despite unsatisfying immediate aneurysm occlusion, the adjunctive effect of the stent is stabilizing or significantly improving long-term anatomical results.

Endovascular treatment of proximal anterior cerebral artery aneurysms.

INTRODUCTION: Aneurysms of the proximal segment of the anterior cerebral artery (A1A) are rare and challenging to treat. No information is available regarding their management by endovascular approach. The aim of this study was to report our experience with endovascular treatment (EVT) of A1As. PATIENTS AND METHODS: A retrospective review of our prospectively maintained database identified all A1As treated in our institution. The clinical charts, procedural data, and angiographic results were reviewed. RESULTS: From April 2004 to August 2008, eight patients were identified and presented with an unruptured A1A. All aneurysms but one were <3 mm in diameter and two aneurysms had a perforator at the neck. Surgery was performed in two patients with an aneurysm <2 mm. Six patients were treated by selective embolization including five patients with balloon-assisted coiling (BAC) and/or via a retrograde approach from the contralateral side through the anterior communicating artery. These adjunctive techniques were used to safely catheterize the sac or to protect a branch at the neck. All patients showed an excellent clinical outcome. A complete aneurysm occlusion was obtained in all but one patient. Follow-up imaging in four patients showed stable results. CONCLUSION: EVT of A1As is feasible and associated with good clinical and anatomical results. Because of their location, small size, and close relationship with perforators, EVT frequently requires the use of BAC and/or a retrograde approach. Our results suggest that EVT is an alternative therapeutic option to surgical clipping if the aneurysm size is compatible with selective embolization.

Dopamine transporter genotype modulates brain activity during a working memory task in children with ADHD.

Dopamine active transporter gene (DAT1) is a candidate gene associated with attention-deficit/hyperactivity disorder (ADHD). The DAT1 variable number tandem repeat (VNTR)-3' polymorphism is functional and 9R carriers have been shown to produce more DAT than 10R homozygotes. We used functional magnetic resonance imaging (fMRI) to investigate the effects of this polymorphism on the neural substrates of working memory (WM) in a small but selected population of children with ADHD, naïve of any psychotropic treatment and without comorbidity. MRI and genotype data were obtained for 36 children (mean age: 10,36 +/- 1,49 years) with combined-type ADHD (9R n = 15) and 25 typically developing children (TDC) (mean age: 9,55 +/- 1,25 years) (9R n = 12). WM performance was similar between conditions. We found a cross-over interaction effect between gene (9R vs. 10R) and diagnosis (TDC vs. ADHD) in the orbito-frontal gyrus, cerebellum and inferior temporal lobe. In these areas, WM-related activity was higher for 9R carriers in ADHD subjects and lower in TDC. In ADHD children only, 10R homozygotes exhibited higher WM-related activity than 9R carriers in a network encompassing the parietal and the temporal lobes, the ventral visual cortex, the orbito-frontal gyrus and the head of the caudate nucleus. There was no significant results in TDC group. Our preliminary findings suggest that DAT1 VNTR polymorphism can modulate WM-related brain activity ADHD children.

The Neural Basis of Speech Perception through Lipreading and Manual Cues: Evidence from Deaf Native Users of Cued Speech.

We present here the first neuroimaging data for perception of Cued Speech (CS) by deaf adults who are native users of CS. CS is a visual mode of communicating a spoken language through a set of manual cues which accompany lipreading and disambiguate it. With CS, sublexical units of the oral language are conveyed clearly and completely through the visual modality without requiring hearing. The comparison of neural processing of CS in deaf individuals with processing of audiovisual (AV) speech in normally hearing individuals represents a unique opportunity to explore the similarities and differences in neural processing of an oral language delivered in a visuo-manual vs. an AV modality. The study included deaf adult participants who were early CS users and native hearing users of French who process speech audiovisually. Words were presented in an event-related fMRI design. Three conditions were presented to each group of participants. The deaf participants saw CS words (manual + lipread), words presented as manual cues alone, and words presented to be lipread without manual cues. The hearing group saw AV spoken words, audio-alone and lipread-alone. Three findings are highlighted. First, the middle and superior temporal gyrus (excluding Heschl's gyrus) and left inferior frontal gyrus pars triangularis constituted a common, amodal neural basis for AV and CS perception. Second, integration was inferred in posterior parts of superior temporal sulcus for audio and lipread information in AV speech, but in the occipito-temporal junction, including MT/V5, for the manual cues and lipreading in CS. Third, the perception of manual cues showed a much greater overlap with the regions activated by CS (manual + lipreading) than lipreading alone did. This supports the notion that manual cues play a larger role than lipreading for CS processing. The present study contributes to a better understanding of the role of manual cues as support of visual speech perception in the framework of the multimodal nature of human communication.

Comparison of functional MR imaging guidance to electrical cortical mapping for targeting selective motor cortex areas in neuropathic pain: a study based on intraoperative stereotactic navigation.

PURPOSE: To assess the concordance between data from functional MR imaging (fMRI) guidance and the intraoperative electrical cortical mapping (iCM) in targeting selective motor cortex areas in refractory neuropathic pain. METHODS: Twenty-one patients (11 women and 10 men; mean age, 55.6 years) with refractory central (ischemic, 8 cases) and neuropathic pain (trigeminal neuropathy, 6 cases; syrinx/amputation/plexus trauma, 7 cases) underwent surgery for the implantation of an epidural electrode for chronic motor cortex stimulation (MCS) with general anesthesia and a frameless neuronavigation system used for the image-guided targeting procedure. All patients were studied by preoperative fMRI and epidural iCM with somatosensory evoked potentials and motor cortex stimulodetection. fMRI investigated systematically motor tasks of both hands and that related to the somatic area (foot or tongue) affected by pain. fMRI data were analyzed with the Statistical Parametric Mapping99 software (initial analysis threshold [AT] corresponding to P < .001), registered in the neuronavigation system and correlated intraoperatively with iCM. Matching of fMRI and iCM was specifically examined, focusing the study on hand mapping. RESULTS: Concordance between contours of fMRI activation area and iCM in precentral gyrus (mean distance, 3.8 mm) was found in 20/21 patients (95%). Because precision of iCM was suboptimal in 7 patients, concordance for more restrictive values of the AT (P < .0001) was found in only 13 of these 20 patients. Concordance was not found in one patient, as result of image distortion and residual motion artifact. CONCLUSIONS: In this study, fMRI guidance provides information that matches those of an independent functional method. These data illustrate the functional accuracy of fMRI guidance for the operative targeting of selective motor cortex areas in neuropathic pain.

Is volume transfer coefficient (K(trans)) related to histologic grade in human gliomas?

PURPOSE: The purpose of this study was to examine the relationship between contrast transfer coefficient [K(trans)] and grade in gliomas. MATERIAL AND METHODS: Median values of K(trans), CBV(T1), and of the 95th percentile (95%) of the distribution (K(trans) [95%] and CBV(T1) [95%]) were calculated in 39 patients with glioma. Group comparisons and post hoc pairwise comparisons were performed. The relationship between variables and grade used Spearman rho and canonical discriminant analysis. The separation of high- from low-grade tumors was separately assessed by using Mann-Whitney U tests and logistic regression. Receiver operator curve analysis was performed for high- and low-grade tumors and grade III and grade IV tumors. RESULTS: There were significant differences between grades for all variables (P < .001). Pairwise comparisons demonstrated significant differences between grades II and III and II and IV for all variables except K(trans), which did not show significance in the grade II and III comparison, and between III and IV for CBV(T1) and CBV(T1) (95%; P < .01). All variables correlated with grade (P < .01). Discriminant analysis showed independent relation between both CBV(T1) and K(trans) (95%) and grade, and the canonical function produced a total correct classification of 74.4% of cases. Logistic regression analysis for low- versus high-grade tumors showed K(trans) (95%) and CBV(T1) to be independent factors (P < .01 and P < .05). CONCLUSION: There are strong independent relationships between both CBV and K(trans) and histologic grade in gliomas. Both measurements show good discriminative power in distinguishing between low- and high-grade tumors with diagnostic sensitivity and specificity >90%.

Grey matter volume differences associated with gender in children with attention-deficit/hyperactivity disorder: A voxel-based morphometry study.

Female participants have been underrepresented in previous structural magnetic resonance imaging reports on attention-deficit/hyperactivity disorder (ADHD). In this study, we used optimized voxel-based morphometry to examine grey matter volumes in a sample of 33 never-medicated children with combined-type ADHD and 27 typically developing (TD) children. We found a gender-by-diagnosis interaction effect in the ventral anterior cingulate cortex (ACC), whereby boys with ADHD exhibited reduced volumes compared with TD boys, while girls with ADHD showed increased volumes when compared with TD girls. Considering the key role played by the ventral ACC in emotional regulation, we discuss the potential contribution of these alterations to gender-specific symptoms' profiles in ADHD.

Grey matter volumes in treatment naïve vs. chronically treated children with attention deficit/hyperactivity disorder: a combined approach.

Psychostimulants are the first-line treatment in attention deficit/hyperactivity disorder (ADHD), but their effects on brain development remain poorly understood. In particular, previous structural magnetic resonance imaging (sMRI) studies only investigated treatment effects on grey matter (GM) volumes in selected regions of interest (ROIs). In this study, voxel-based morphometry (VBM) was used to assess medication-related GM volume differences across the entire brain. Automated tracing measurements of selected ROIs were also obtained. Three groups (77 participants aged 7-to-13 year old) underwent MRI scans and were compared: never-medicated children with ADHD (n=33), medicated (methylphenidate) children with ADHD (n=20) and typically developing children (TD; n=24). Optimised VBM was used to investigate regional GM volumes, controlling for age and gender. Automated tracing procedures were also used to assess the average volume of the caudate nucleus, the amygdala and the nucleus accumbens. When compared to both medicated children with ADHD and TD children, never-medicated children with ADHD exhibited decreased GM volume in the insula and in the middle temporal gyrus. When compared to TD children, medicated children with ADHD had decreased GM volume in the middle frontal gyrus and in the precentral gyrus. Finally, ROI analyses revealed a significant association between duration of treatment and GM volume of the left nucleus accumbens in medicated children with ADHD. In conclusion, this study documents potential methylphenidate-related GM volume normalization and deviation in previously unexplored brain structures, and reports a positive association between treatment history and GM volume in the nucleus accumbens, a key region for reward-processing.

Structural correlates of COMT Val158Met polymorphism in childhood ADHD: a voxel-based morphometry study.

OBJECTIVES: The Val158-allele of the catechol-O-methyltransferase (COMT) Val158Met (rs4680) functional polymorphism has been identified as a risk factor for antisocial behaviour in attention-deficit/hyperactivity disorder (ADHD). Here, we used voxel-based morphometry to investigate the effects of Val158Met polymorphism on grey matter (GM) volumes in a sample of 7-13-year-old children. METHODS: MRI and genotype data were obtained for 38 children with combined-type ADHD and 24 typically developing (TD) children. Four regions of interest were identified: striatum, cerebellum, temporal lobe and inferior frontal gyrus (IFG). RESULTS: When compared to TD children, those with ADHD had a significant decrease of GM volume in the IFG. Volume in this region was negatively correlated with ratings of hyperactivity/impulsivity symptoms. Furthermore, the smaller GM volume in the IFG was attributed to the presence of the Met158-allele, as only children with ADHD carrying a Met158-allele exhibited such decrease in the IFG. Children with ADHD homozygotes for the Val158-allele presented increased GM volume in the caudate nucleus when compared with TD children. CONCLUSIONS: This study provides the first evidence of a modulation of ADHD-related GM volume alterations by Val158Met in two key regions, possibly mediating the relationship between Val158Met polymorphism and antisocial behaviour in children with ADHD.

An unusual cause of visual loss: involvement of bilateral lateral geniculate bodies.

We report the clinical and radiologic features of a 31-year-old woman who suffered incongruous binasal and bitemporal visual field defects and severe sudden visual loss due to hypoperfusion of bilateral lateral geniculate bodies following anaphylactic shock induced by 500 mg amoxicillin per os. Complete neuroophthalmologic examinations were performed regularly for visual acuity, color vision, pupillary reflexes, and visual fields. Additional testing was performed by means of MR imaging of the brain and CSF analysis. Follow-up was performed for 12 months. Vision loss was acute and severe, its onset bilateral and simultaneous. The patient recovered visual acuity of 1.0 within 7 weeks. Color vision was abnormal in both eyes but gradually improved to normal. Visual fields were characterized by incongruous binasal and bitemporal defects, but they reduced progressively. Cerebral MR imaging confirmed the presence of symmetrical lesions confined exclusively within both lateral geniculate bodies. These lesions were best seen on T1-weighted and fluid-attenuated inversion recovery images as high-signal-intensity areas suggestive of hemorrhagic ischemia. CSF analysis was normal and aseptic. Blood tests and cultures excluded any microbial infection. We conclude that shock may induce a bilateral isolated ischemia of the lateral geniculate bodies, resulting in incongruous binasal and bitemporal visual field defects and severe visual loss. MR imaging is the optimal imaging technique to confirm the diagnosis and for follow-up.