A case of methanol intoxication with optic neuropathy visualized on STIR sequence of MR images]

We report a 24-year-old man with severe methanol intoxication, who showed cerebral and optic nerve damages on MRI. He was admitted to our hospital with an acute onset of unconsciousness and severe metabolic acidosis, and was immediately treated by hemodialysis. His serum methanol concentration was 261.5 mg/dl. Although this methanol concentration was lethal, he was rescued by intensive care. Three days after admission, brain MRI was performed. Diffusion weighted images showed abnormal hyperintensities in bilateral putamina, subcortical white matter and cerebellar hemispheres. STIR sequence revealed bilateral optic nerve swelling with irregular hyperintense rims. These MRI features might reflect the optic nerve damages, mainly demyelination of the optic nerves caused by a myelinoclastic effect of formic acid, a metabolite of methanol.     

Cerebellar ataxia with hypogonadotropic hypogonadism]

A 38-year-old male began to develop progressive difficulty in speaking and walking in his early thirties. He was the younger of four siblings from the parents of consanguineous marriage. Allegedly, his brother had showed similar symptoms. On examination, he was sexually underdeveloped with absent facial and public hair as well as small firm testes. He showed typical eunuchoid habitus. Neurologically, his gait was markedly ataxic and speech was explosive. He was mildly demented (verbal IQ = 66) and eupholic. Generalized hyperreflexia and positive Babinski were observed. There were no signs of extrapyramidal, autonomic or peripheral nerve involvement. Laboratory data were remarkable for low level of serum gonadotropins and low level of HVA and 5-HIAA in CSF. Plasma long-chain fatty acids were normal and lysosomal enzymes in leukocyte including ASA showed no significant change. EEG showed diffuse slow activities with spikes on photic stimulation. The endocrinological studies including insulin-induced hypoglycemia and TRH test demonstrated hypothalamus-pituitary axis dysfunction. GH-RH test showed delayed response of GH secretion, suggesting the presence of hypothalamic disturbance. Brain CT showed cerebellar atrophy and symmetrical low density area in the cerebral white matter. On MRI, T2 weighed image showed diffuse and symmetrical high intensity area in the cerebral white matter. High signal intensities were also noted in the bilateral thalamus and pons. It is suggested that both hypogonadotropic hypogonadism and cerebellar ataxia in this disease may have a common underlying pathology of white matter.     

吸食海洛因致海绵状白质脑病的CT及MRI诊断

目的评价海洛因中毒所致的海绵状白质脑病的CT、MRI表现及诊断价值.方法搜集6例海洛因海绵状白质脑病的CT及MRI资料,全部患者均进行MRI检查,检查序列包括T1WI、T2WI、FLAIR序列,其中2例同时行颅脑CT扫描. 结果全部患者MRI显示对称性双侧小脑半球、大脑半球后部、内囊后肢、胼胝体压部、脑干等皮质下白质为主的多发性大片状长T1、长T2信号,加强后病灶无强化;2例行头颅CT检查显示两大脑半球皮质下白质、基底节及两侧小脑呈对称性广泛低密度灶,无占位效应.结论海洛因中毒所致的海绵状白质脑病具有特征性的MRI表现,MRI对本病的诊断具有重要价值.     

An autopsy case of drug‐induced diffuse cerebral axonopathic leukoencephalopathy: The pathogenesis in relation to reversible posterior leukoencephalopathy syndrome

An autopsy case of diffuse axonopathic leukoencephalopathy induced by drug treatment is reported. A 70‐year‐old woman with multiple myeloma developed encephalopathy several days after completing a course of intravenous human immunoglobulin (IVIg) and granulocyte‐colony stimulating factor (G‐CSF), and died within I month. T2‐weighted MRI demonstrated multifocal high‐signal areas in the bilateral cerebral white matter, especially in the right frontal lobe. Neuropathologically, multifocal hydropic axonal swelling with a poor glial reaction was recognized diffusely in the bilateral deep cerebral white matter, being especially marked in the frontal lobe. The cortex, subcortical U‐fibers, corpus callosum, and anterior commissure were spared. The cerebellar white matter also showed similar changes, albeit less marked, but the brainstem was spared. Microscopically, the myeloma involvement of the CNS was limited to the dura, and the cerebral arteries showed slight atherosclerosis, but neither thrombi nor angitis. This case, although ultimately fatal, neurologically and neuroradiologically resembled reversible posterior leukoencephalopathy syndrome (RPLS) induced by IVIg and/or G‐CSF, and the nature and selective distribution of the neuropathological changes suggested that the pathogenesis involved vasospasm of the bilateral internal carotid artery and the main trunks of the cerebral arteries, due to unknown cause, inducing ischemia in the deep white matter, which is supplied by long nutrient arteries.     

Bilateral wallerian degeneration of the middle cerebellar peduncles due to unilateral pontine infarction

We report the case of a patient with bilateral and symmetrical T2 hyperintensities of the middle cerebellar peduncles. She had a history of left pontine infarction 8 months before. This was attributed to bilateral Wallerian degeneration. MR Spectroscopy showed decreased N-acetyl aspartate/Creatine (NAA/Cr) ratio in the cerebellar peduncles as well as in the whole cerebellum. We hypothesize that this could reflect neuronal degeneration following a stroke.     

Dementia with leukoencephalopathy in systemic lupus erythematosus

Neurologic manifestations, afflicting up to 70% of SLE patients, include psychosis, seizures, chorea, neuropathies, and stroke. MRI is useful in evaluation of lupus patients and several reports have documented cerebral atrophy or focal hyperintensities. We report an unusual MRI appearance in a 56-year-old woman with SLE, diagnosed on the basis of pleuritis, lymphopenia, anti-DNA antibodies, and neurologic involvement. She reported recent onset of Raynaud's phenomenon and generalized macular rash. She presented after two months of gradual deterioration with memory loss, flattened affect, dysphagia, dysarthria, anomia, and somnolence, without focal neurologic signs. Investigations included elevated ESR, reduced complement, normal CSF without oligoclonal bands, negative viral serology, normal hormone and vitamin levels, normal renal and hepatic function. Neuropsychologic testing showed widespread impairment (WAIS-R: FSIQ-63; WMS-69; DRS-98; RCPM-14; WAB AQ-78.8). CT was normal but MRI showed strikingly symmetric, confluent hyperintensities extensively involving cerebral and cerebellar white matter on T1 and T2 weighted scans. Basal ganglia and subependymal and subcortical white matter were spared. Treated with prednisone, the patient made a gradual, but incomplete, recovery. These MRI findings may reflect widespread vasculopathy or direct immunologic brain insult with or without immunologic blood-brain barrier disruption.     

L-2-hydroxyglutaric aciduria in two siblings

Two Pakistani siblings with L-2-hydroxyglutaric aciduria are reported herein. A 6-year-old male and a 2-year-old female, born to consanguineous parents, had chronic slowly progressive neurodegenerative disorder with insidious onset after infancy. Mental regression and seizures were evident in both patients, whereas cerebellar dysfunction was the main motor handicap in the male and pyramidal symptoms were prominent in the female. Magnetic resonance imaging revealed bilateral symmetrical abnormal signal in the subcortical white matter, internal and external capsules, basal ganglia, and dentate nuclei. The underlying metabolic defect, which is likely inherited in an autosomal recessive mode, remains unknown in this disorder.     

An interesting case of metabolic dystonia: L-2 hydroxyglutaric aciduria

L-2-hydroxyglutaric aciduria (L-2-HGA), a neurometabolic disorder caused by mutations in the L-2 hydroxyglutarate dehydrogenase (L-2-HGDH) gene, presents with psychomotor retardation, cerebellar ataxia, extrapyramidal symptoms, macrocephaly and seizures. Characteristic magnetic resonance imaging findings include subcortical cerebral white matter abnormalities with T2 hyperintensities of the dentate nucleus, globus pallidus, putamen and caudate nucleus. The diagnosis can be confirmed by elevated urinary L-2 hydroxyglutaric acid and mutational analysis of the L-2-HGDH gene. We report two siblings with dystonia diagnosed by classical neuroimaging findings with elevated urinary 2 hydroxyglutaric acid. Riboflavin therapy has shown promising results in a subset of cases, thus highlighting the importance of making the diagnosis in these patients.     

Quantitative magnetic resonance imaging differences between Alzheimer disease with and without subcortical lacunes

Previous reports showed that patients with Alzheimer disease (AD) frequently have coexisting vascular-related pathologies, such as cerebral infarcts and white matter lesions. The aim of this study was to determine the effects of subcortical lacunar infarcts on brain structure in patients with AD. Semi-automated tissue segmentation and volumetry of magnetic resonance imaging data were performed in 38 AD patients without lacunes (AD-L), 24 AD patients with subcortical lacunes (AD+L), and 40 age-matched cognitively healthy subjects without lacunes. The following tissue volumes were quantified, expressed as percentage of total intracranial volume: ventricular cerebrospinal fluid (CSF), sulcal CSF, cortical gray matter (GM), subcortical GM, white matter (WM), white matter signal hyperintensities (WMSH), lacunes, and hippocampus. There was no difference in the Mini-Mental State Examination between the two AD groups. AD+L patients compared with AD-L subjects had significantly greater volumes of WMSH and ventricular CSF spaces (as expected) but smaller sulcal CSF spaces and no significant increase in cortical GM atrophy (both unexpected). In the AD groups, ventricular CSF correlated inversely with cortical GM but not with WM; sulcal CSF correlated inversely with cortical GM and WM. Cognitive impairment was associated with sulcal CSF volume but not with volumes of WMSH or lacunes. In conclusion, the presence of subcortical lacunes in those with AD is associated with more WM lesions and ventriculomegaly but not with cortical atrophy.     

Clinical neuroimaging features and outcome in molybdenum cofactor deficiency

Molybdenum cofactor deficiency predominantly affects the central nervous system. There are limited data on long-term outcome or brain magnetic resonance imaging (MRI) features. We examined the clinical, brain MRI, biochemical, genetic, and electroencephalographic features and outcome in 8 children with a diagnosis of molybdenum cofactor deficiency observed in our institution over 10 years. Two modes of presentation were identified: early (classical) onset with predominantly epileptic encephalopathy in 6 neonates, and late (atypical) with global developmental impairment in 2 children. Children in both groups had varying degrees of motor, language, and visual impairment. There were no deaths. Brain MRI demonstrated cerebral infarction in all but one child in the atypical group. Distinctive features were best observed on early brain MRI: acute symmetrical involvement of the globus pallidi and subthalamic regions coexisting with older cerebral hemisphere infarction, chronic lesions suggestive of a prenatal insult, pontocerebellar hypoplasia with retrocerebellar cyst, and presence of a distinctive band at the cortical/subcortical white matter. Sequential imaging revealed progressive pontine atrophy and enlargement of retrocerebellar cyst. The brain MRI of one child with atypical presentation (verbal dyspraxia, lens dislocation) showed symmetrical cerebellar deep nuclei signal abnormality without cerebral infarction. Imaging pattern on early brain MRI (<1 week) may prompt the diagnosis, potentially allowing early treatment and disease modifications.     

Acute disseminated encephalomyelitis associated with parainfluenza virus infection of childhood

Acute disseminated encephalomyelitis associated with the parainfluenza virus has rarely been reported in childhood. A 2.5-year-old girl with acute disseminated encephalomyelitis, who developed bilateral symmetrical lesions in the basal ganglion, thalamus, corpus callosum, cerebral subcortical white matter, and cerebellar medulla on brain magnetic resonance imaging is described. Serological confirmation of parainfluenza virus infection was made 2 weeks following the onset of neurological symptoms. Four months later, the patient had a full recovery. At present, 3 years later, no relapse has been reported and she is leading a normal life. Our case is of interest because of its rarity, the striking brain magnetic resonance imaging, and the good neurological outcome.     

Diffusion tensor imaging abnormalities in focal cortical dysplasia

PURPOSE: Focal cortical dysplasia (FCD) is one of the most common underlying pathologic substrates in patients with medically intractable epilepsy. While magnetic resonance imaging (MRI) evidence of FCD is an important predictor of good surgical outcome, conventional MRI is not sensitive enough to detect all lesions. Previous reports of diffusion tensor imaging (DTI) abnormalities in FCD suggest the potential of DTI in the detection of FCD. The purpose of this study was to study subcortical white matter underlying small lesions of FCD using DTI. METHODS: Five patients with medically intractable epilepsy and FCD were investigated. Diffusion tensor imaging images were acquired (20 contiguous 3 mm thick axial slices) with maps of fractional anisotropy (FA), trace apparent diffusion coefficient (trace/3 ADC), and principal eigenvalues (ADC parallel and ADC perpendicular to white matter tracts) being calculated for each slice. Region of interest analysis was used to compare subcortical white matter ipsilateral and contralateral to the lesion. RESULTS: Three subjects with FCD associated with underlying white matter hyperintensities on T2 weighted MRI were observed to have increased trace/3 ADC, reduced fractional anisotropy and increased perpendicular water diffusivity which was greater than the relative increase in the parallel diffusivity. No DTI abnormalities were identified in two patients with FCD without white matter hyperintensities on conventional T2-weighted MRI. CONCLUSIONS: While DTI abnormalities in FCD with obvious white matter involvement are consistent with micro-structural degradation of the underlying subcortical white matter, DTI changes were not identified in FCD lesions with normal appearing white matter.     

Portal‐systemic shunt encephalopathy presenting with diffuse cerebral white matter lesion: An autopsy case

We report herein an autopsy case of portal‐systemic encephalopathy (PSE) presenting with diffuse tissue rarefaction in the cerebral deep white matter. Clinically, the patient showed recurrent episodes of unconsciousness, abnormal behavior and urinary incontinence, as well as flapping tremor. Cognitive impairment and peripheral neuropathy developed following recurrent episodes. Although conventional arterial portography revealed a small portal‐systemic collateral vessel of a left gastro‐renal venous shunt, abdominal CT and liver biopsy showed no evidence of liver cirrhosis and serum ammonia level showed a mild increase. T2‐weighted MRI demonstrated symmetrical signal hyperintensities in the deep white matter. Neuropathological findings showed Alzheimer type II astrocytes in the deep layers of the cerebral cortices and severe tissue rarefaction with no or slight reactive astrocytosis in the subcortical and deep white matter. These white matter changes have been reported infrequently in patients with PSE. The present case suggests that chronic PSE without liver cirrhosis may develop diffuse white matter lesions.     

Neuroimaging of major depression in Parkinson's disease: Cortical thickness,cortical and subcortical volume,and spectroscopy findings

Depression is the most common psychiatric disorder in Parkinson's disease (PD). The aim of this study was to compare PD patients with current Major Depressive Disorder (MDD), lifetime MDD, and no MDD using three neuroimaging techniques. A total of 43 PD patients were selected and divided into three groups: (i) current MDD (n = 15), (ii) previous MDD without current MDD (n = 10); and (iii) control group (no current or lifetime MDD; n = 18). All participants underwent magnetic resonance imaging to evaluate cortical thickness, cortical and subcortical volume, and spectroscopy in the bilateral putamen and cingulate cortex. Volumetric analysis showed volume decreases in frontal and temporal areas, bilateral amygdala, and left cerebellar white matter in the lifetime MDD group compared to the control group. Furthermore, the volumes of the anterior cingulate cortex, right amygdala, and left cerebellar white matter were smaller in the group with current MDD compared to the control group. Regarding cortical thickness, the left rostral anterior cingulate gyrus of the group with previous MDD was thinner compared to the control group. There was a weak negative correlation between the NAA/Cre ratio in the right putamen and depressive symptoms. The results suggested current and lifetime MDD have a negative impact on the neurodegenerative process of PD, with decreased volume and/or reduction of cortical thickness in temporal and frontal areas, anterior cingulate cortex, amygdala, and cerebellar white matter.     

Cerebral hemodynamics and white matter hyperintensities in CADASIL.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary small-vessel disease caused by mutations in the NOTCH3 gene on chromosome 19. On magnetic resonance imaging (MRI), subcortical white matter hyperintensities and lacunar infarcts are visualized. It is unknown whether a decrease in cerebral blood flow or cerebrovascular reactivity is primarily responsible for the development of white matter hyperintensities and lacunar infarcts. The authors used phase-contrast MRI in 40 NOTCH3 mutation carriers (mean age 45 +/- 10 years) and 22 nonmutated family members (mean age 39 +/- 12 years), to assess baseline total cerebral blood flow (TCBF) and cerebrovascular reactivity after acetazolamide. Mean baseline TCBF was significantly decreased in NOTCH3 mutation carriers. In young subjects, baseline TCBF was significantly lower than in nonmutation carriers (mean difference 124 mL/min). Furthermore, baseline TCBF did not differ significantly between mutation carriers with minimal and mutation carriers with moderate or severe white matter hyperintensities. No significant difference in mean cerebrovascular reactivity was found between mutation carriers and nonmutation carriers. This study suggests that a decrease in baseline TCBF in NOTCH3 mutation carriers precedes the development of white matter hyperintensities.     

可逆性后部白质脑病综合征的临床及影像学特点

目的 探讨可逆性后部白质脑病综合征（PRES）的临床和影像学特点。方法 回顾性分析7例PRES患者临床及影像学资料。结果 本组继发于妊娠高血压综合征3例,肾功能衰竭3例,高血压1例。临床表现：7例均有头痛及视物模糊,伴有癫痫发作6例,恶心、呕吐4例,轻偏瘫、共济失调各1例。6例行头颅CT检查,3例枕叶低密度影,其中2例广泛脑白质水肿;1例多发小血肿;2例未发现异常。7例MRI检查显示枕叶均受累,同时伴小脑受累3例,脑干2例,额顶叶皮质下白质2例,尾状核、丘脑各1例。在脑叶呈脑回样、在其他部位呈斑片样异常信号;T1WI呈略低或等信号,T2WI和Fair像呈高信号。2例增强扫描1例无强化,1例呈脑回样、斑片样和环状强化。4例DWI扫描,2例呈略高信号,1例呈低信号,1例未见异常。结论 头痛、视觉障碍和癫痫发作是PRES主要临床表现,影像学特征主要为大脑后部白质对称性长T1、长T2信号。     

Giant Axonal Neuropathy: MRS Findings

Giant axonal neuropathy (GAN) is a rare genetic disease of childhood involving the central and peripheral nervous systems. Axonal loss with several giant axons filled with neurofilaments is the main histopathological feature of peripheral nerve biopsies in this disease. Routine neuroimaging studies reveal diffuse hyperintensities in cerebral and cerebellar white matter. In this case report, the authors present the brain magnetic resonance spectroscopic features (normal N-acetylaspartate/creatine and increased choline/creatine and myoinositol/creatine ratios), which might indicate the absence of neuroaxonal loss and the presence of significant demyelination and glial proliferation in white matter, of an 11-year-old boy diagnosed with GAN.     

Reduced cerebral glucose metabolism in subjects with incidental hyperintensities on magnetic resonance imaging

OBJECTIVE: To clarify the significance of incidental and asymptomatic hyperintensities on T(2)-weighted magnetic resonance images (MRI) in adults, we examined the relationship between a variety of these lesions and cerebral metabolism evaluated by positron emission tomography (PET) with (18)F-labeled fluorodeoxyglucose ([(18)F]FDG). SUBJECTS AND METHODS: Two hundred and thirty-one persons with hyperintensities on T(2)-weighted MRI but without overt neurological disease (mean age 60+/-9 years) were studied. MR hyperintensities were classified into deep and/or subcortical white matter hyperintensities (DSWMHs), periventricular hyperintensities (PVHs) and hyperintensities in the basal ganglia and/or thalamus (HBGTs). The relationship between these lesions and cerebral metabolic rate of glucose (CMRgl) measured by [(18)F]FDG-PET was investigated. RESULTS: The CMRgl values in white matter and cerebral cortex in the group with severe PVHs were lower than those in the group with mild PVHs (P<0.0001 and P<0.005). Although the severity of PVHs was associated with the numbers of DSWMHs and HBGTs, the results of multivariate analysis showed a significant relationship of PVHs to glucose metabolism in cerebral cortex and white matter. CONCLUSIONS: We conclude that increasing severity of MRI hyperintensities in adults is associated with a deterioration of cerebral metabolism. In particular, involvement of PVHs may be a marker of widespread deterioration of cortical metabolism.     

Major depressive disorder with anger attacks and subcortical MRI white matter hyperintensities

Previous reports of increased rates of cardiovascular risk factors in major depressive disorder (MDD) with anger attacks led the authors to hypothesize that MDD with anger attacks may be associated with brain vascular changes (magnetic resonance imaging white matter hyperintensities [WMHs]). Sixty-five subjects meeting DSM-III-R criteria for major depressive disorder were administered brain magnetic resonance imaging scans at 1.5T to detect T2 WMH. The severity of brain WMH was classified with the Fazekas scale. We used standardized scales to assess melancholic MDD, atypical MDD, and MDD with anger attacks. In logistic regression analyses, MDD with anger attacks was associated with higher severity of subcortical WMH and of total WMH, but not with periventricular WMH. Atypical and melancholic MDD subtypes were not significantly associated with brain WMH. In conclusion, subcortical brain vascular lesions may be more prevalent or severe in MDD with anger attacks.     

Late cognitive and radiographic changes related to radiotherapy: initial prospective findings

BACKGROUND: Assumptions about the damaging effects of radiotherapy (XRT) are based on studies in which total dose, dose fraction, treatment volume, degree of malignancy, chemotherapy, tumor recurrence, and neurologic comorbidity interact with XRT effects. This is a prospective, long-term study of XRT effects in adults, in which total dose and dose fraction were constrained and data related to tumor recurrence and neurologic comorbidity (e.g., hypertension) were excluded. METHODS: The effects of XRT on the cognitive and radiographic outcomes of 26 patients with low-grade, supratentorial, brain tumors yearly from baseline (6 weeks after surgery and immediately before XRT) and yearly to 6 years were examined. Radiographic findings were examined regionally. RESULTS: Selective cognitive declines (in visual memory) emerged only at 5 years, whereas ratings of clinical MRI (T2 images) showed mild accumulation of hyperintensities with post-treatment onset from 6 months to 3 years, with no further progression. White matter atrophy and total hyperintensities demonstrated this effect, with subcortical and deep white matter, corpus callosum, cerebellar structures, and pons accounting for these changes over time. About half of the patients demonstrated cognitive decline and treatment-related hyperintensities. CONCLUSIONS: There was no evidence of a general cognitive decline or progression of white matter changes after 3 years. Results argue for limited damage from XRT at this frequently used dose and volume in the absence of other clinical risk factors.