S. G. Srikanth

Pyruvate: an in vivo marker of cestodal infestation of the human brain on proton MR spectroscopy.

To study intracranial cestodal cysts using in vivo proton magnetic resonance spectroscopy (1H MRS) in an effort to identify metabolite(s) that may help in recognizing the parasitic etiology and, perhaps, viability of such tapeworm cysts. Cestodal infestations of the human central nervous system (CNS)—cysticercosis and hydatidosis—are not rare. Identification of a scolex is considered diagnostic of cysticercosis on imaging. In its absence, however, the features are non‐specific.

Clinicoradiological features of tuberculous meningitis in patients over 50 years of age

Background and aim: Tuberculous meningitis (TBM) is a debilitating form of CNS tuberculosis with a high morbidity and mortality in spite of treatment. The diagnosis is based on clinical, radiological and laboratory features. The classical CT features of basal exudates, hydrocephalus, infarcts and granulomas have been mostly reported in younger individuals. Our aim was to study imaging features of TB meningitis in adults over the age of 50 years. Materials and methods: Clinical, imaging and laboratory features of 53 adult patients over the age of 50 years (sixth to eighth decades) were studied retrospectively. Diagnosis of TBM was based on clinical and laboratory features. Results: Imaging features were the conspicuous absence of typical features of TBM (ie, basal meningeal enhancement, hydrocephalus, infarcts/granulomas were seen in only a minority of patients). Conclusions: CT features of TBM in elderly patients were few, atypical and non-contributory for diagnosis, probably because of age related immune senescence. Strong clinical suspicion and correlation with laboratory findings is necessary for early diagnosis.

Intracranial metastasis from a glandular variant of atrial myxoma

SummaryBackground. Intracranial metastases from atrial myxoma producing symptomatic mass lesions are very rare with only ten examples reported in the literature. We report a patient with multiple metastases from a cardiac myxoma which had an unusual histopathology mimicking an adenocarcinoma.Clinical presentation. A 35 year old man presented with left facio-brachial focal motor seizures unresponsive to antiepileptic drugs and these episodes preceded the symptoms of cardiac myxoma. The seizures worsened a year following resection of the cardiac myxoma. The MRI of the brain revealed multiple lesions of heterogeneous intensity, partly solid and cystic situated in the right fronto-parietal, left temporal and occipital lobes.Findings. Right fronto-parietal craniotomy revealed lesions with haemorrhagic, calcified areas and a large cystic component was decompressed. Histological examination of the lesions in the brain demonstrated prominent glandular differentiation, identical in morphology to the primary cardiac lesion of a glandular variant of atrial myxoma.Conclusion. This report highlights the rare presentation of atrial myxoma with intracranial metastases and reviews previously reported examples. This is only the second case report of a glandular variant of atrial myxoma with metastases to the brain. A pathologist, unaware of this unusual variant of primary atrial myxoma, may mistake the intracranial lesion for a metastatic adenocarcinoma.

Restricted diffusion in Canavan disease

IntroductionCanavan disease is a megalencephalic leukodystrophy due to deficiency of the enzyme aspartoacylase. Proton MR spectroscopy finding of elevated N-acetyl-l-aspartate is considered diagnostic of Canavan disease.Case reportWe report a case of Canavan disease, which showed restricted diffusion in diffusion-weighted imaging and discuss the cause of it.

Hypertrophic cranial pachymeningitis in countries endemic for tuberculosis: Diagnostic and therapeutic dilemmas

Hypertrophic cranial pachymeningitis (HCP) is an uncommon disorder with few studies correlating clinical, imaging and histopathological features. The aim of this study was to describe clinical and laboratory observations and therapeutic options of patients with HCP. Eleven patients with HCP (M:F 6:5; age range, 23-52 years) were evaluated over 10 years. Etiology was ascertained by MRI and laboratory tests and confirmed by biopsy of meninges and/or brain (7), nasal mucosa (1), mediastinal lymph node (1), muscle (2) or conjunctiva (2). Salient clinical features were headache (7), multiple cranial neuropathies (8), visual disturbances (6), seizures (2) and hemiparesis (2). Abnormal tests included: rapid erythrocyte sedimentation rate (3), positive serum venereal disease testing (1), chest CT abnormalities (4/6) and positive Mantoux test (2/5). Cerebrospinal fluid changes (10/11) revealed the following: cell count 0-47/mm(3); protein 14-95 mg/mL; and glucose of 44-79 mg/mL. Contrast MRI revealed a variable extent of thickened dura mater in all patients. Histopathology (n=11) confirmed chronic inflammation (100%) and provided specific etiology in six (vasculitis [2], sarcoidosis [2], tuberculosis [1], Wegeners granulomatosis [1]). Treatment included steroids only (4), anti-tubercular therapy with steroids (5), penicillin (1) and cyclophosphamide and plasmapheresis (1). During follow-up (27.0+/-26.3 months) there was significant recovery (9/9). On serial imaging (4), the lesion remained the same in three and resolved partially in one patient. HCP, despite frequently posing diagnostic and therapeutic challenges, has favorable outcome when treated appropriately.

Malformations of cortical development (MCDs) and epilepsy: Experience from a tertiary care center in south India

INTRODUCTION Malformations of cortical development (MCDs) are increasingly recognized as important cause of epilepsy, especially refractory epilepsy. In developing countries like India, where the facilities for sophisticated imaging are not easily accessible to all, the prevalence and the types of cortical malformations are largely unknown. Hence this preliminary study has been undertaken to examine the relation between epilepsy and malformations of cortical development in a resource-limited setting. AIMS To study various types of malformations of cortical development (MCDs) associated with epilepsy and to correlate with their clinical semiology. SETTINGS AND DESIGN The study was conducted in a tertiary care neurological center in south India. Cohort included all patients with epilepsy associated with cortical malformation on neuroimaging. METHODS AND MATERIALS Neuroimaging data of all patients with epilepsy were evaluated for a 5-year period from 1998 to 2003, for the presence of cortical malformations. The case records of those patients with cortical malformations were taken from the medical records department and the clinical and electrophysiological data were analyzed. RESULTS We are reporting 34 cases of MCDs evaluated during the 5-year period. The mean age of the cohort was 15.1 (+/-12.2) years, with a range from 3 months to 45 years and 52.9% were males. Mean age at seizure onset was 7.2 years (+/-7.8), with a mean duration of seizure of 8.1 years (+/-7.7). Delayed motor and mental milestones were present in 15 patients (44.1%) and positive family history of seizure/epilepsy was seen in 9 patients (26.5%). Cortical malformations were most often associated with partial seizures (19/34, 55.9%). The most common type of seizure was complex partial seizure, seen in 12 patients (35.3%). Majority had very frequent, uncontrolled seizures with 16 (47.1%) patients having a seizure frequency of more than one per day. Heterotopias were seen in 14 patients (41.2%), in isolation in 5 (14.7%) patients and in combination with other malformations in 9 (26.5%) patients. Pachygyria was present as an isolated anomaly in five (14.7%) patients and combined with other abnormalities in eight (23.5%) patients. Cortical dysplasia was seen in 5 (14.7%) patients, hemimegalencephaly in two patients, polymicrogyria in two patients, lissencephaly and schizencephaly were seen in one patient each. EEG demonstrated focal epileptiform discharges in 59.1%, while generalized epileptiform discharges were seen in 22.7% of patients. Twenty-seven out of 34 (79.4%) patients had refractory/difficult to treat epilepsy. CONCLUSIONS Malformations of cortical development are a heterogeneous group of disorders, associated with developmental delay and refractory seizures but seizures usually do not have pathognomonic semiologic features. Possibility of MCDs should be considered during the evaluation of refractory epilepsy cases.

Neurological manifestations of Ehlers-Danlos Syndrome.

Ehlers-Danlos Syndrome (EDS) is more identified for its cutaneous features but its neurological manifestations have not received the focused attention. Four patients of Ehlers-Danlos Syndrome (EDS) with neurological manifestations were evaluated for phenotypic data. These four men were from three families and two had consanguineous parentage. The mean age at onset and presentation of neurological symptoms were 10.5 years and 19 years respectively. Patient 1 presented with bilateral optic atrophy, sensorineural deafness, cerebellar ataxia and neuropathy. Patient 2 had marfanoid habitus, chorea and cerebellar ataxia. Patient 3 had action and percussion myotonia, wasting and weakness of sternocleidomastoid and distal limb muscles. Patient 4 had action myotonia, mirror movements of both hands and neuropathy. MRI of brain showed right parietal polymicrogyria. Neuroaxis involvement at multiple levels in EDS may have prognostic significance.

13-year-old boy with cerebellar cystic mass

A 13-year-old boy presented to the neurosurgical services with complaints of bifrontal headache for 1 year and progressive deterioration of vision in both eyes. The headache had worsened for the past 1 month, associated with vomiting at the height of headache. Fifteen days prior to admission to the hospital his visual acuity worsened to an extent just to perceive light. General systemic examination was normal. The neurological evaluation revealed visual acuity of only perception of light, bilateral secondary optic atrophy, right sixth cranial nerve paresis, and left cerebellar signs. On cranial CT scanning an oval, hypodense [Figure 1A) left cerebellar cystic mass was noted, nonenhancing with contrast [Figure 1B). Fourth ventricle was compressed with resultant hydrocephalus. With a clinical diagnosis of cystic cerebellar tumor, the cyst was excised by suboccipital craniectomy. The cyst ruptured during the surgery and was found to be lined by thin white membrane and filled with xanthochromic fluid.

A 30-year-old male with diffuse white matter lesions.

A 30-year-old male presented with fever and cough withexpectoration of 3-month duration. He was diagnosed to havepulmonary tuberculosis and antituberculous therapy was ini-tiated. He developed progressive lower limb weakness over1 month. He was detected to be HIV seropositive. At the timeof admission to the hospital, he was dull, withdrawn, and hadspastic paraparesis (Grade 4/5 power). Cerebrospinal fluid(CSF) studies revealed 120 cells/mm

Dysmyelinating neuropathy in benign form of megalencephalic leukoencephalopathy with subcortical cysts: a novel observation from south India.

A 37-year-old gentleman presented with macrocephaly since early childhood and progressive impairment of motor and cognitive functions. Magnetic resonance imaging revealed extensive white matter involvement and frontotemporal subcortical cysts. Absent ankle jerk and abnormal nerve conduction study raised a possibility of associated peripheral neuropathy. Sural nerve biopsy was suggestive of dysmyelinating neuropathy. This report serves to expand the clinical spectrum of this rare leukodystrophy.