Neuroimaging in epilepsy.

Epilepsy is a common neurological disorder with diverse etiologies. Neuroimaging plays an important role in workup of patients with epilepsy. It helps to identify brain pathologies that require specific treatment; and also in formulating syndromic and etiological diagnoses so as to give patients and their relatives an accurate prognosis. Magnetic resonance imaging, specially the 3 tesla MRI is the imaging of choice because of its ability to detect small lesions like mesial temporal sclerosis, cortical dysplasias, small tumors, etc that are not detected by conventional MR or CT scan of brain. Identification of these lesions often helps in managing refractory epilepsies more effectively. However, cost and non-availability of MR in large part of the country necessitate the use of CT as an alternative. CT is often the initial investigation and also useful in acute situations. Functional imagings are used for pre-surgical work-up of refractory epilepsy cases with an aim to identify the epileptogenic focus and to delineate functional areas nearing the focus.

Burden among stroke caregivers: results of a community-based study from Kolkata, India.

BACKGROUND AND PURPOSE: Stroke causes significant caregiver (CG) stress, which is under-reported in India. This study assesses the financial, physical, psychological, and family burden on CG of stroke patients in an urban community. METHODS: Cross-sectional survey of stroke patients and CG were selected from a community-based registry using validated scales through face-to-face interviews. RESULTS: Data were available from 199 stroke survivors and a similar number of CG. Increased workload, related anxiety and depression, and sleep disturbance were reported by 70%, 76%, and 43% of CG, respectively, whereas >80% reported financial worry, which was greater among slum dwellers and less educated families. CG of patients with dementia and depression experienced greater stress. Female CG received more appreciation and family bonding was well-maintained. CONCLUSIONS: Financial stress was prominent and common among the socioeconomically weaker section. Psychological stress is similar to that of other studies. Women CG received greater appreciation. Family bonding was well-preserved in contrast to that of a western report.

A longitudinal study of epilepsy in Kolkata, India.

PURPOSE: This study aimed to determine the prevalence, incidence, and mortality rates of epilepsy in the city of Kolkata, India. This is the first such longitudinal study in a heterogeneous urban Indian population. METHODS: A two-stage door-to-door survey of a stratified random sample was undertaken within the municipal limits of Kolkata. Trained field workers detected and interviewed the cases using a simple screening questionnaire, and the detailed follow-up was done by neurologists. The survey was conducted annually for five consecutive years from March 2003 through February 2008. RESULTS: A total of 52,377 (52.74% men) individuals were screened. There were 309 prevalent and 66 incident cases of active epilepsy. The prevalence and average annual incidence rate (AAIR) with 95% confidence interval (CI), age-standardized to World Standard Population, were 572.8 (509.79-641.54) per 100,000 and 27.27 (21.03-34.80) per 100,000 per year, respectively. The age-specific incidence rates of epilepsy showed bimodal distribution. During the 5-year period, 20 cases of active epilepsy died. The average annual mortality rate (AAMR) was 7.63 (95% CI 4.45-11.26) per 100,000 population per year. Compared to the general population of Kolkata, the all-cause standardized mortality ratio (SMR) for persons with epilepsy was 2.58 overall (men 3.67; women 1.77). There was no significant difference between slum and nonslum dwellers in epidemiologic parameters. CONCLUSIONS: The AAIR of epilepsy is comparable to that observed in developed countries, but AAMR is higher. The all-cause SMR for epilepsy relative to the general population is, however, similar to that of developed nations.

Multifacctorial origin and clinical presentations of epilepsy in west Bengal.

Epilepsy is a brain dysfunction characterised by unpredictable occurrence of seizures. There are various causes and presentations of epilepsy but in many cases no definite cause is found. In the present work an effort has been made to search different causes and presentations of epilepsy in West Bengal. In this respect 66 subjects of different age groups suffering from epilepsy were chosen during a period of 1 1/2 years (June 2003 to November 2004). They were closely followed with thorough history taking, clinical examination and relevant investigations. Partial seizures comparised 57.6% cases whereas generalised seizure accounted for rest 42.4% cases. Idiopathic epilepsy was found to be highest in number (59.0%) followed by infective (15.2%) and and post-traumatic (7.6%). Positive family history was obtained in 35.9% cases, history of birth asphyxia in 25.6% cases and history of febrile convulsion in 20.5% cases of idiopathic epilepsy. In a certain percentage of idiopathic cases various psychosocial factors were found to be associated with epilepsy.

Neurological disorders in children and adolescents.

OBJECTIVE: To ascertain the prevalence of active epilepsy, febrile seizures (FS), cerebral palsy (CP) and tic disorders (TD) in aged 19 years or less. METHODS: This was a cross-sectional observational study conducted as a two-stage door-to-door survey of a stratified randomly selected population in 2003-04. Trained field workers screened the population followed by case examination by the field neurologist. RESULTS: A total of 16979 (male 8898, female 8081) subjects aged

Identification of neuroanatomical substrates of set-shifting ability: evidence from patients with focal brain lesions.

This work concerns the investigation of executive functions in patients with focal brain lesion. In order to identify the underlying substrates for executive functions, 54 patients with focal cortical (n=30), subcortical (n=13) and cerebellar damage (n=10) (M=9; F=1) in the age range of 24-65 years with a minimum of Class V education have been investigated. The patients were admitted to the Department of Neuromedicine of Bangur Institute of Neurology, Calcutta. Each patient with focal lesion was matched with a healthy normal subject controlling for age and education. The socio-economic background was also taken into consideration. Controls were selected from the families of other patients admitted to the institution and also from individuals who volunteered to act as controls. Here too, rigid criteria have been followed to select the normals. Mini Mental State Examination (MMSE) and General Health Questionnaire (GHQ) were administered to screen out the neurological and psychiatric abnormalities in selection of normal control and Wisconsin Card Sorting Test (WCST) was administered to find out the executive function, in terms of set-shifting ability. Since standard anatomical groupings can obscure more specific brain-behavior relations, group-comparison design does not always allow determination of the effective lesion responsible for a particular deficit (Godefroy et al., 1998). The Classification and Regression Tree (CART) analysis has been used to determine the brain-behavior relationships. The result reveals that the frontal lobes are essential determinants of set-shifting capacity. However, for optimal execution of set-shifting function, the frontal lobes require participation of other cortical, subcortical and cerebellar regions. The result has been discussed in the light of the existing theories and research reports.

Community survey of primary dystonia in the city of Kolkata, India.

An epidemiological study on dystonia has not been reported from India. As part of a major study to find out the prevalence of major neurological disorders in the large urban city of Kolkata, Eastern India, we planned to determine the prevalence of primary dystonia. The study design was a cross-sectional study of a sample population obtained through stratified random selection and conducted in a two-stage procedure of screening by a nonprofessional team followed by confirmation of screened positive cases by the study neurologist. A total population of 52,377 was screened, and 29 subjects with dystonia were diagnosed. Out of them 23 subjects had primary dystonias [crude prevalence rate (CPR), 43.91/100,000; 95% confidence interval (CI), 28.41-64.81; age-standardized rates to world standard population, 49.06 (95% CI,31.74-72.41)] and all cases were focal type and predominantly of limb dystonia variety. Mean onset of dystonias were earlier in women (43.5 years) as compared to men (46.6 years). Thus our study on primary dystonia shows higher prevalence when compared with that of many studies globally, predominantly of focal type, earlier onset among women, and more cases of limb dystonias when compared with more prominent blepharospasm and cervical dystonias in western reports.

A prospective community-based study of stroke in Kolkata, India.

BACKGROUND AND PURPOSE: Information on essential stroke parameters are lacking in India. This population-based study on stroke disorder was undertaken in the city of Kolkata, India, to determine the subtypes, prevalence, incidence, and case fatality rates of stroke. METHODS: This was a longitudinal descriptive study comprising 2-stage door-to-door survey of a stratified randomly selected sample of the city population, conducted twice per year for 2 successive years from March 2003 to February 2005. RESULTS: Out of the screened population of 52,377 (27 626 men, 24 751 women), the age standardized prevalence rate of stroke to world standard population is 545.10 (95% CI, 479.86 to 617.05) per 100,000 persons. The age standardized average annual incidence rate to world standard population of first-ever-in-a-lifetime stroke is 145.30 (95% CI, 120.39 to 174.74) per 100,000 persons per year. Thirty-day case fatality rate is 41.08% (95% CI, 30.66 to 53.80). Women have higher incidence and case fatality rates. Despite divergence on socioeconomic status between the slum and nonslum dwellers, stroke parameters were not significantly different. CONCLUSIONS: The age standardized prevalence and incidence rates of stroke in this study are similar to or higher than many Western nations. The overall case fatality rate is among the highest category of stroke fatality in the world. The women have higher incidence and case fatality rates compared with men.

A random sample survey for prevalence of major neurological disorders in Kolkata.

BACKGROUND & OBJECTIVES: Large scale epidemiological studies on neurological disorders are very few in India. We therefore planned to conduct a cross-sectional population-based epidemiological study on a stratified randomly selected sample from the city of Kolkata to study the prevalence of major neurological disorders such as epilepsy, stroke, dementia and Parkinsonism. METHODS: The method of case ascertainment was two- stage house-to-house survey; the first stage was undertaken by a field team consisting of four field workers and a neuropsychologist. Screening questionnaire based on National Institute of Mental Health and Neuro Sciences (NIMHANS) protocol was used. In the second stage a neurologist examined all the screened positive cases. RESULTS: A total of 52,377 subjects participated in the study. The crude prevalence rates (per 100,000 population) of major neurological disorders with 95 per cent confidence intervals (95% CI) and age adjusted rates (AAR) based on US 2000 population were 557.5 (95% CI 496.17-624.40 and AAR - 516.77) in epilepsy, 486.85 (95% CI 377.0 to 551.11 and AAR-765.68) in stroke, 87.82 (95% CI 64.02-117.50 and AAR-168.4) in dementia and 45.82 (95% CI 29.64-67.63 and AAR-71.64) in Parkinsonism. The weighted prevalence rates (per 100,000) of the whole population based on re-screening of 10 per cent of negative samples were 763.89 (95% CI 690.55- 842.57) in epilepsy, 624.32 (95% CI 555.64-699.24) in stroke and 139.37 (95% CI 108.71-176.06) in dementia. INTERPRETATION & CONCLUSION: A high rate of stroke and overall lower prevalence of Parkinsonism and dementia was recorded as compared to western studies. High prevalence rate of stroke emphasizes the need to study incidence, morbidity and mortality profile of stroke including its socio-economic impact and also case-control analysis to determine the underlying risk factors.

Spectrum of peripheral neuropathy in eastern India.

Peripheral neuropathies constitute an important group of disorders in neurological practice. Very few systematic studies on peripheral neuropathies are available from India. Hence we conducted a prospective study in two large hospitals from Kolkata, the biggest city of eastern India in order to find out the spectrum of peripheral neuropathy. This prospective study was carried out from June 1998 to January 2003 on admitted patients with symptoms and signs of peripheral neuropathy. Two hundred and twenty-five patients were evaluated (one hundred and twenty-five from an industrial hospital and one hundred from an academic tertiary care institution at Kolkata). Result showed that most of the cases of peripheral neuropathy belonged to fourth decade with men dominance. Common varieties of neuropathy were Guillain-Barré syndrome, diabetes mellitus, hereditary motor sensory neuropathy, chronic inflammatory demyelinating neuropathy, drugs and toxin related. Unusual varieties were Isaacs's syndrome and X-linked hereditary motor-sensory neuropathy. One case of neuropathy due to Plasmodium vivax has received intravenous immunoglobulin therapy. The type of peripheral neuropathy in hospital-based patients in eastern India was similar to other parts of country excepting some sporadic types due to infective or genetic causes and a large number of cases of undetermined aetiology exist despite detailed investigations.

Dementia in india--a critical appraisal.

Dementia is a clinical syndrome characterised by acquired loss of cognitive and emotional abilities that interfere with activities of daily living. It is a disease of the older adults. The overall prevalence of dementia in developed countries has been reported to be between 5% and 10% after 60 or 65 years and older. India is the second largest populous country. The prevalence doubles with every five-year increase in age. Looking at some studies, it appears that the prevalence of dementia in India is lower as compared to developed countries and even from other developing countries. The probable reasons for lower prevalence in India are enumerated as: False negatives, low life expectancy, shorter survival and duration of disease, low age-specific incidence. Risk factors include greater age, female sex, less education, positive family history, Down's syndrome, stroke and its risk factors, head trauma with loss of conscionsness and thyroid diseases. Protective factors include higher education, APOE2 gene, intake of antioxidant substances, use of anti-inflammatory drugs, oestrogen supplements in women and also cigarette smoking (controversial). Alzheimer's disease has been found to be commonest cause of dementia. Patients of dementia require proper evaluation and management requires a multidisciplinary approach. The government and the social organisations should come forward and only a concerted effort of all people in every sphere of life will enable to tackle the new menace of this country.

Central nervous system fungal infection--a report of three cases.

Fungal infections of the central nervous system in three apparently immunocompetent patients are being reported. Two cases of cerebral aspergillosis presenting as intracranial granulomas such as rhinocerebral and intracranial forms, and one of cryptococcal meningitis could be successfully diagnosed by newer diagnostic modality such as antigen detection techniques. The case with cryptococcal infection had typical neuroimaging feature which helped to suspect the underlying diagnosis. Aspergillus galactomannan detection in the cerebrospinal fluid helped in the early diagnosis and appropriate therapy of one patient.

Epidemiological study of neurological disorders in a rural population of Eastern India.

The study was conducted to determine the prevalence of neurological diseases in a rural community in Eastern India through a community based survey with the help of trained doctors following on WHO protocol (1981) translated in local vernacular, among 20842 rural residents (male-11037, female-9805, census India-1991, the State of West Bengal in Eastern India) over a period of one yearfrom May 1992 to April 1993 in two phases. Professionals screened the patients by house to house survey in the first phase and later on they were examined in details in temporary clinics in second phase. A total of 606 patients were identified and classified according to well-defined diagnostic criteria. The commonest diseases per 100,000 were headache: 870, vertebral diseases with neurological involvement: 540, seizure disorders: 360, vertigo: 230, stroke: 147, movement disorders: 140, peripheral neuropathy: 80. The age and sex specific prevalence showed increasing frequency of neurological disorders with advancing age in both genders excepting slight dip in the fourth and fifth decades among females. In the present study prevalence of headache, epilepsy, stroke and Parkinson's disease was lower than that of in the Western countries. Different inclusion criteria, multiethnicity, different environmental factors, poor medical facility and insufficient number of aged population may be responsible for lower prevalence of chronic neurological disorders as compared to Western countries. Increase in the life expectancy in future will lead to increasing burden of chronic neurological diseases in absolute term in Indian society considering the one billion population at present.

Helicobacter pylori, gastric juice, and arterial ammonia levels in patients with cirrhosis.

Helicobacter pylori urease activity is a potential source of ammonia in the stomach of patients with cirrhosis. However, the possible role of H. pylori in the pathogenesis of hepatic encephalopathy deserves further investigations. The current study evaluates the relationship among H. pylori infection, gastric juice ammonia concentrations, and arterial ammonia levels in patients with cirrhosis. Overall, 14 patients with cirrhosis with overt hepatic encephalopathy, 19 with subclinical hepatic encephalopathy, and 13 without encephalopathy were enrolled. All patients underwent upper endoscopy, and gastric biopsy specimens were taken for H. pylori assessment (rapid urease test, histology, and culture). A gastric juice sample and an arterial blood sample were obtained for ammonia level assessment. Patients with overt encephalopathy had both higher arterial ammonia levels and a more severe hepatic impairment than the remaining patients, whereas gastric juice ammonia concentrations did not differ among the three groups. H. pylori prevalence was similar among groups. Patients with H. pylori infection had significantly higher gastric juice ammonia concentrations than those without infection (2.3 +/- 1.3 vs. 0.9 +/- 0.6 mmol/L, respectively; p = 0.003); however, no difference in arterial ammonia levels emerged between the two groups (37.7 +/- 18.6 vs. 37.6 +/- 18.8 micromol/L, respectively). No significant correlation was found between gastric juice ammonia concentrations and arterial ammonia levels. The data suggest that liver impairment remains crucial in ammonia disposal in patients with cirrhosis, whereas H. pylori infection does not seem to play a major role in the pathogenesis of hyperammonemia in these patients.