Perilesional gliosis around solitary cerebral parenchymal cysticerci and long-term seizure outcome: a prospective study using serial magnetization transfer imaging.

PURPOSE: Epilepsy following solitary cerebral cysticercosis (SCC) is possibly caused by perilesional gliosis, best visualized on magnetization transfer imaging (MTI).This study aims to describe development of gliosis around SCC by prospective serial MTI and to correlate this gliosis with long-term seizure outcome. METHODS: We randomized 123 patients with SCC and new-onset seizures to treatment with albendazole plus antiepileptics (treatment), or antiepileptics only (control), and performed magnetic resonance imaging (MRI) scans at 0, 3, 6, 12, and 24 months. Prospective follow-up data regarding seizure outcome up to 5 years later were collected. MRI studies were analyzed for lesion characteristics and perilesional magnetization transfer (MT) hyperintensity. KEY FINDINGS: Clinical and radiologic data of 77 patients were analyzed. Demographic and seizure characteristics were similar in treatment and control groups. Clinical data were available up to 64 months after enrollment. At 12 months, 89.5% patients were seizure-free. MTI is more sensitive than routine imaging for detection of perilesional gliosis. Albendazole treatment did not affect imaging or clinical outcome, including development of gliosis. Independent of duration of follow-up, gliosis was associated with more seizures, and with seizure recurrence at 12 months; duration of seizures and antiepileptic therapy was longer. Gliosis was not dependent on seizure type or stage of degeneration at enrollment or persistence/calcification of the lesion. SIGNIFICANCE: Perilesional gliosis around SCC helps prognosticate seizure outcome. Poorer outcome in patients with persistent lesions is likely to be related to mechanisms other than gliosis. The lack of effect of albendazole on seizure outcome may be due to its inability to decrease formation of gliosis.

Supratentorial and cerebellar liponeurocytomas: report of four cases with review of literature.

Liponeurocytoma is not exclusive to the cerebellar or fourth ventricular location. Since its inclusion in the central nervous system tumor classification in 2000, six cases with similar radiological, histomorphological and immunohistochemical features have also been described in the lateral ventricles. In the present study, we report clinical, radiological and pathological findings of three supratentorial and one cerebellar liponeurocytoma from our records, evaluated with an extensive panel of immunohistochemistry, and review published cases in the literature. The immunohistochemical pattern of supratentorial and infratentorial liponeurocytomas are almost identical, which indicates that these tumors are homologous.

Eccentric target sign in cerebral toxoplasmosis: neuropathological correlate to the imaging feature.

Cerebral toxoplasmosis remains one of the most common focal brain lesions in patients with acquired immune deficiency syndrome (AIDS). Diagnosis is a challenge because on cranial imaging it closely mimics central nervous system lymphoma, primary and metastatic central nervous system (CNS) tumors, or other intracranial infections like tuberculoma or abscesses. A magnetic resonance imaging (MRI) feature on postcontrast T1-weighted sequences considered pathognomonic of toxoplasmosis is the "eccentric target sign." The pathological correlate of this imaging sign has been speculative. Herein we correlate the underlying histopathology to the MR feature of eccentric target sign in a patient with autopsy-proven HIV/AIDS-related cerebral toxoplasmosis. The central enhancing core of the target seen on MRI was produced by a leash of inflamed vessels extending down the length of the sulcus that was surrounded by concentric zones of necrosis and a wall composed of histiocytes and proliferating blood vessels, with impaired permeability producing the peripheral enhancing rim.

Vocal cord paralysis after percutaneous embolization of a vagal paraganglioma--the role of intraoperative nerve monitoring.

The value of preoperative embolization is well established in the management of paragangliomas. Percutaneous direct intratumoral embolization has been described as a safe and effective technique to achieve devascularization of these tumors, thereby reducing intraoperative blood loss. However, the present article presents a case in which a patient developed vocal cord palsy after percutaneous embolization of a vagal paraganglioma. In view of the present findings, the possibility of intraoperative nerve monitoring needs to be explored to ensure safety of this procedure.

Randomized controlled trial of albendazole in new onset epilepsy and MRI confirmed solitary cerebral cysticercal lesion: effect on long-term seizure outcome.

No trials to date have focused on long-term seizure outcome in solitary cerebral cysticercal lesion (SCCL), which is believed to produce a relatively benign form of epilepsy. This is a prospective randomized controlled study to evaluate the effect of Albendazole on long-term seizure outcome in patients with MRI-confirmed solitary cerebral cysticercal lesion (SCCL). One hundred and twenty-three patients with new-onset seizures and SCCL on contrast MRI were randomized to treatment with albendazole and followed for up to five years with serial MRI and clinical evaluation. At final analysis 103 patients (M-54, F-49) with a mean age of 18.6+/-10.7 years and follow-up period more than 12 months were included. The mean follow-up duration was 31.4+/-14.8 months (12-64). At one month follow-up more patients receiving albendazole were seizure-free (62% versus 49% for controls). Subsequently there was no significant difference in overall seizure outcome between the two groups. There was no correlation between seizure semiology, albendazole therapy and long-term seizure outcome. Baseline MRI showed active lesions in all; 23% remained active at 12 months with no difference between the albendazole and control groups. Patients whose lesions resolved at 12 months showed better seizure outcome. Reduction in mean cyst area was greater in the albendazole group as compared to the controls and the difference at six months was significant (p<0.05). At three months follow-up perilesional edema also resolved faster in albendazole group (p<0.05). Thus, albendazole did not alter the long-term seizure outcome in patients with SCCL and epilepsy. However, albendazole hastened resolution of SCCL on MRI, but interestingly 23% of lesions were still active 12 months after treatment.

Marchiafava-Bignami disease: Two cases with magnetic resonance imaging and positron emission tomography scan findings.

We report two patients with Marchiafava-Bignami disease (MBD). A 38-year-old male with chronic alcohol abuse developed acute onset cerebellar ataxia and altered sensorium. He was diagnosed to have acute form (Type II) of MBD. Magnetic resonance imaging (MRI) showed extensive lesions involving the corpus callosum in its entire extent and also bilateral corona radiata and centrum semiovale. Corpus callosum had heterogeneous signal changes with ring enhancement. Positron emission tomography scan demonstrated reduced cerebral glucose metabolism diffusely over both the cerebral hemispheres. The second patient was 55-year-old male with chronic alcohol intake developed acute onset vomiting followed by behavioral abnormalities and altered sensorium. MRI showed diffuse lesion involving entire corpus callosum with suggestion of necrosis. Both the patients subsequently recovered, the first patient is back to his previous occupation and the second patient could be rehabilitated with some lighter work in his previous work place. Functional brain imaging may help to understand the pathogenesis of acute MBD and possibly the behavioral manifestations.

Neuropathology of viral infections of the central nervous system.

Many viral infections of the nervous system cause stereotyped pathologic features and overlapping clinical and imaging features. Neuroimaging usually offers neuroanatomical localization of the pathology, degree of involvement of the nervous system, and response to therapy during follow up in a few instances. Neuroimaging is a useful adjunct for diagnosis.

Case of fulminant-SSPE associated with measles genotype D7 from India: an autopsy study.

Subacute sclerosing panencephalitis (SSPE), a post-measles progressive neurological disorder is still common in India because of indifferent vaccination compliance. However, the acute fulminant form of SSPE is extremely rare. An unusual case of fulminant SSPE in an 18-year-old man from south India with an ultra-short course of 19 days presenting with hemiparesis in absence of myoclonus and progressive cognitive decline, is reported. MRI showed frontal and parieto-occipital demyelination extending to nuclear areas. Antimeasles antibodies were demonstrable in CSF and serum with oligoclonal bands in CSF despite normal CSF protein and cell count. At autopsy, unlike classical SSPE, oligodendroglia containing measles viral antigen was sparse despite florid necrotizing leukoencephalitis with acute demyelination. Measles virus was isolated from the brain with hypermutation in M gene confirming the diagnosis. Phylogenetic analysis of the viral genotype indicated that it belonged to D7 genotype which is considered rare in India.

Is total excision of spinal neurenteric cysts possible?

Spinal neurenteric cysts are intradural cystic lesions. These represent a part of the spectrum of developmental anomalies. These are rare lesions. Most of the data in literature is review of case reports. This made us evaluate our results of 23 cases and review the literature. This is a retrospective study of 23 patients managed at our institute over 20 years. The slides were retrieved and histopathological features studied. Twenty patients were less than 30 years old and 21 were males. Follow-up was available for 21 patients with mean duration of 71 months (range 2 months to 23 years). The typical presentation was backache with progressive neurological deficits pertaining to the level. Atypical presentations as acute onset, recurrent episodic events and aseptic meningitis were also noted. The cervicothoracic region was the most common site. 16 patients had cyst in intradural extramedullary plane and seven had intramedullary location. Associated vertebral anomalies as hemivertebrae, Klippel-Feil and spina bifida were noted in seven patients. There were two histological types of cysts with no correlation between the type of cysts and associated vertebral anomalies and extent of outcome. Partial excision though had higher risk of recurrence, was not associated with poorer outcome. Dorsal approach is an acceptable route with reasonably good results for this lesion. Spinal neurenteric cysts present at younger age with varied clinical presentations. These are commonly located intradurally ventral to the cord. Histological types have no effect on the outcome. Total excision is the choice of treatment. However, partial excision is a feasible option in intramedullary lesions and when significant adhesions occur. Although associated with higher risk of recurrence, the outcome is still good in these patients on re-excision.

Nephrogenic diabetes insipidus: a rare cause of intracranial calcification in children.

Causes of intracranial calcification in children are numerous. This article describes an unusual cause of intracranial calcification and white matter changes in a child, namely, nephrogenic diabetes insipidus. A 4-year-old boy presented with history of polyuria, polydipsia, failure to thrive, and developmental delay. On examination, he had mild dysmorphic features and spastic paraparesis. Evaluation showed findings suggestive of nephrogenic diabetes insipidus. Computed tomography and magnetic resonance imaging revealed calcification and signal changes in the frontal and parietal subcortical white matter and gray white junction in the parietal and occipital lobes. The involvement of the white matter, in addition to the calcification in this disease, is stressed because it may predict the neurologic outcome.

Volumetric analysis of hippocampal sub-regions in late onset depression: a 3 tesla magnetic resonance imaging study.

BACKGROUND: While many studies have reported reduced volume of hippocampus in late onset depression (LOD), the status of hippocampus sub-regions (anterior/posterior) is yet to be explored. Evaluating hippocampal sub-regions might facilitate better elucidation of the neurobiological basis of LOD. METHODS: Twenty five elderly subjects with LOD (mean age=65.28yr, SD=5.73, 15 females) and 20 healthy controls (mean age=65.35yr, SD=5.67, 7 females) were examined using 3-tesla magnetic resonance imaging (MRI). They were also evaluated with Montgomery Asberg Depression Rating Scale (MADRS) and Hindi Mental State Examination (HMSE). We examined the difference in volume of Hippocampal sub-regions between the LOD group and control group controlling for the age, sex and intracranial volume. RESULTS: Left posterior hippocampus volume was significantly smaller in LOD group than the control group (1.01±0.19ml vs 1.16±0.25ml, F=7.50, p=0.009). There was a similar trend for the right posterior hippocampus (1.08±0.19ml vs 1.18±0.27ml, F=3.18, p=0.082). Depression severity (mean MADRS score=20.64±8.99) had a significant negative correlation with volumes of right posterior hippocampus (r=-0.37, p=0.012) and left posterior hippocampus (r=-0.46, p=0.001) in the LOD group. CONCLUSIONS: Specific reduction of posterior hippocampus volume and its relationship with depression severity indicates sub region specific hippocampal volumetric abnormalities in LOD. Future studies need to evaluate sub region specific hippocampal volume in LOD longitudinally for better understanding of the pathogenesis of LOD in view of the functional differences between anterior and posterior hippocampus.

Cryptococcal choroid plexitis as a mass lesion: MR imaging and histopathologic correlation.

Cryptococcosis is a relatively common mycotic infection of the CNS caused by a ubiquitous saprophytic fungus. We present an unusual case of CNS cryptococcosis in an immunocompetent patient. Florid choroid plexitis resulted in the formation of intraventricular enhancing mass lesions that filled the ventricles and were hyperintense to associated periventricular edema on T2-weighted MR images. We also noted lesions corresponding to microcystic, dilated Virchow-Robin spaces in the basal ganglia that were characteristic of cryptococcal infection.

Cerebral tubercular thrombophlebitis presenting as venous infarct: Magnetic resonance imaging and pathologic correlation.

Central nervous system involvement by tuberculosis to produce basal meningitis, hydrocephalus, arteritis and infarcts is well-known, the brunt of the pathology being borne by the arterial vasculature to produce neurological sequelae. However, tuberculous thrombophlebitis causing venous infarction is exceedingly rare. We present imaging and pathological features of two autopsy proven cases of tuberculous thrombophlebitis with venous infarcts involving superficial venous system in one and deep venous system in the other. This is the first study presenting radiopathologic correlation of this rare complication. Tuberculous thrombophlebitis should be suspected if basal exudates and multiple white matter T2 hyperintensities are seen on neuroimaging and the imaging protocol should include both magnetic resonance arteriogram and venogram.

Comprehensive evaluation of cortical structure abnormalities in drug-naïve, adult patients with obsessive-compulsive disorder: a surface-based morphometry study.

The study objective was to comprehensively evaluate drug-naïve, adult patients with Obsessive Compulsive Disorder (OCD) for cortical structure abnormalities in comparison with healthy controls. In this cross-sectional study of case-control design, Magnetic Resonance Imaging (1-mm) was performed in drug-naïve OCD patients (N = 50) & age- sex-, education- and handedness-matched healthy controls (N = 40). We examined cortical volume, thickness, surface area & local Gyrification Index (LGI) through a completely automated surface-based morphometric analysis using FreeSurfer software. OCD symptoms and insight were assessed using Yale-Brown Obsessive Compulsive Symptom (Y-BOCS) check-list and severity scale. Illness severity was assessed using Clinical Global Impression Severity (CGI-S) Scale. OCD patients had significantly deficient volume, thickness and surface area of right anterior cingulate gyrus (ACG). Right lingual gyrus surface area was found to be significantly decreased in patients. Y-BOCS obsession score had significant negative correlation with left frontal pole volume. Y-BOCS compulsion score had significant negative correlations with right ACG volume and surface area and right lateral orbitofrontal cortex LGI. CGI-Severity score had significant negative correlations with right lingual gyrus volume, thickness and surface area as well as right lateral orbitofrontal area. Y-BOCS insight score showed a significant negative correlation with LGI of left medial OFC and left rostral ACG. Identification of novel deficits involving occipital brain regions and first-time observations of relevant correlations between various illness characteristics and cortical measures in OCD patients supports a network involving anterior cingulate, orbitofrontal and occipital brain regions in the pathogenesis of OCD.

Biotin-responsive basal ganglia disease: a treatable and reversible neurological disorder of childhood.

Biotin-responsive basal ganglia disease is a rare childhood neurological disorder of uncertain etiology that is treatable if suspected and diagnosed. Only few cases have been reported earlier in literature. We report a case of biotin-responsive basal ganglia disease suspected clinically, corroborated by neuroimaging and a dramatic response to biotin therapy.

Cranial MRI in acute hyperammonemic encephalopathy.

Cranial magnetic resonance imaging was performed in three cases of acute hyperammonemic encephalopathy with three diverse etiologies: infantile citrullinemia, acute hepatic encephalopathy, and proximal urea cycle disorder. All three patients exhibited diffuse extensive cortical signal changes and swelling. Neurologic outcome was poor in all three cases. Knowledge of the magnetic resonance imaging findings of hyperammonemic encephalopathy may help in early diagnosis and treatment and could influence the neurologic outcome.

Clinicopathological study of tuberculous brain abscess.

Central nervous system tuberculosis is still one of the leading causes of morbidity in the developing world, and tuberculous abscess is one of its uncommon manifesting forms. It closely mimics a pyogenic abscess clinically, radiologically, and histologically. An accurate diagnosis is imperative due to therapeutic implications. In this study, 21 cases of tuberculous abscesses encountered over a period of 13 years (1995-2007) were reviewed to study the clinical, radiological, and histopathological spectrum of the disease. The presence of palisading epithelioid cells and sheets of foamy histiocytes, enclosing a neutrophillic exudate rich in fibrin with nuclear debris, were clues as to suspicion of a tuberculous abscess. The demonstration of acid fast bacilli in the wall of the abscess or necrotic contents by microscopy or culture is essential to confirm the diagnosis of tuberculous abscess. A high index of clinical suspicion is necessary particularly in countries endemic for tuberculosis to ensure an accurate diagnosis and application of an appropriate therapy.

A variant form of mucolipidosis IV: report on 4 patients from the Indian subcontinent.

The clinical manifestations and histopathologic and neuroimaging findings in 4 Indian patients with a variant form of mucolipidosis IV are described. The presenting symptoms were psychomotor delay, spastic paraplegia, and mild mental retardation. One patient also had visual deterioration due to optic atrophy. None had corneal or retinal abnormalities. Magnetic resonance imaging in 3 patients showed a uniformly thin corpus callosum in all patients and white matter changes in 2 patients. Electron microscopic examination of skin biopsy specimens revealed storage bodies characteristic of mucolipidosis IV. These patients differ from previously described patients with this disorder in the absence of corneal abnormalities and in their presentation with spastic paraplegia during the second decade of life. Correct diagnosis is needed for genetic counseling, prognostication. and reduction of additional familial burden of this rare disease.