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Biomedical subjects

K Radhakrishnan

Publications and source records attributed to K Radhakrishnan.

At least 73 records · Page 4Linked to original sources

Idiopathic intracranial hypertension (pseudotumor cerebri). Descriptive epidemiology in Rochester, Minn, 1976 to 1990.

The medical records-linkage system of the Mayo Clinic was used to identify cases of idiopathic intracranial hypertension in the 15-year period, 1976 through 1990, among the population of Rochester, Minn. Nine patients (eight women and one man) were identified, corresponding to an average annual age-adjusted incidence rate per 100,000 of 0.9 for the total and 1.6 for the female population. In females aged 15 to 44 years, idiopathic intracranial hypertension occurred at a rate of 3.3 per 100,000 per year; for those defined as obese (body mass index > 26), the rate rose to 7.9. Median follow-up was 2.7 years (range, 5 months to 15 years). Three of 18 eyes developed visual impairment; this was mild in all cases.

Adolescent↗

Epidemiology of idiopathic intracranial hypertension: a prospective and case-control study.

An epidemiologic survey of idiopathic intracranial hypertension (IIH) in Benghazi, Libya, over a period from September 1982 through August 1989 ascertained 81 patients. The group was comprised of 76 females and 5 males. Ages ranged from 8 to 55 years; the mean +/- S.D. was 28.6 +/- 7.9 for women and 21.0 +/- 14.5 for men. The average crude annual incidence rates for IIH per 100,000 persons were 2.2 for the total and 4.3 for females for all ages (3.2 for the total and 5.9 for the females when adjusted to the 1980 United States population). In females aged 15-44 years, IIH occurred at a rate of 12.0 per 100,000 per year; for those defined as obese, the rate rose to 21.4. Moderate to severe visual loss occurred as a sequelae in 20% of our patients. The extent of visual loss did not correlate with age at diagnosis, duration of symptoms, degree of obesity, use of oral contraceptive pills, cerebrospinal fluid (CSF) opening pressure, steroid treatment, or recurrence. We found no correlation between CSF protein and opening pressure. We conducted a case-control study on 40 consecutive female incident IIH patients and 80 age-matched female control subjects. Obesity and recent weight gain occurred more frequently in patients. More patients were married and more had irregular menses. The incidence rate for IIH described in our study is three to four times higher than that reported from the United States.

Adolescent↗

Trauma and multiple sclerosis: a population-based cohort study from Olmsted County, Minnesota.

Utilizing the Olmsted County, Minnesota, population-based records-linkage resource at Mayo Clinic, we identified an incidence and a prevalence cohort with multiple sclerosis (MS), a head injury cohort, and a lumbar disk surgery cohort to evaluate the association between mechanical trauma and MS onset or exacerbation. The MS cohorts consisted of 225 incidence cases (1905 to 1991) and 164 prevalence cases (December 1, 1991) of definite MS in the population of Olmsted County. We assessed the effect of mechanical trauma in the form of spinal injury or extremity fracture with regard to precipitation of MS or exacerbation of an existing neurologic deficit. Fifty-four episodes of trauma, as defined, occurred among 39 MS prevalence cases; most occurred 10 years or more after the onset of disease and were associated with existing MS-related disability. We compared the final disability status of the groups with and without trauma. We found no correlation between the occurrence of peripheral fractures and the onset of MS, exacerbation of MS, or final disability due to MS in the prevalence cohort. In a cohort of 819 head injury cases from the Olmsted County population, none developed MS within 6 months of the trauma. In a lumber disk surgery cohort of 942 local residents, there were five with MS, but onset of MS had preceded the spinal surgery in four of the five. Thus, we found no association of head injury and spinal disk surgery with onset of MS.

Cohort Studies↗

Conjugal amyotrophic lateral sclerosis: report of a young married couple.

We report a 38-year-old nurse who developed amyotrophic lateral sclerosis (ALS) beginning in September 1990. In May 1991, her 38-year-old husband developed dysarthria, which progressed to typical ALS. This is the fourth report in the literature of conjugal ALS occurring outside of Guam. Although this event is most likely due to coincidence, exogenous agents should be considered in the etiology of ALS.

Adult↗

Mechanical trauma as a risk factor in classic amyotrophic lateral sclerosis: lack of epidemiologic evidence.

We have examined the relationship between mechanical injuries and the subsequent development of classic amyotrophic lateral sclerosis (ALS) through a critical review of the literature. Only prospective evaluation of a large cohort of trauma victims can provide an unbiased answer to this controversy. However, such an evaluation would be prohibitively expensive, and the results would not be available in our lifetime. The results of retrospective case-control studies are conflicting in part because of biases in the selection of patients and controls, poor definition of the nature and extent of the trauma and its chronological relationship to the onset of ALS, and a non-uniform approach to the collection of antecedent information. More rigorously designed studies show no association of ALS to antecedent trauma. The existing data thus do not suggest that mechanical trauma is a risk factor for ALS. Future case-control studies should conform to a standardized methodology. The critical analysis presented here of the research on the purported connection between mechanical injury and ALS may serve as a model for the evaluation of the role of trauma in other chronic diseases. Application of these methodological principles may bring increased scientific rigor to assessing the frequently litigated question of what constitutes a true trauma sequela.

Adult↗

Clinical and computed tomography analysis of intracerebral haemorrhage.

The clinical records and computed tomography scans of 50 consecutive patients with intracerebral haemorrhage (ICH) were analysed. Putaminal (48%) and thalamic (16%) ICH comprised the largest group, followed by cerebellar haemorrhage (12%). Intraventricular haemorrhage was observed in 14 cases, a majority being secondary to parenchymal haemorrhage. Hypertension remained the most important risk factor, occurring in 64% of the whole group and 83% of those with putaminal ICH. No predisposing factors for the haemorrhage were identified in 28% of patients. Twenty-seven patients were comatose; the incidence of coma in association with intraventricular haemorrhage was 79%. At the third week, 13 patients had died, a mortality rate of 26%.

Adolescent↗

Fluorotic radiculomyelopathy in a Libyan male.

A middle-aged male resident of Benghazi, northeastern Libya, with radiological features of skeletal fluorosis associated with cervical radiculomyelopathy is reported. This is believed to be the first documentation of such a disorder from this non-tropical, non-endemic region.

Bone Diseases, Metabolic↗

Sickle cell trait and stroke in the young adult.

Two young patients with sickle cell trait (AS haemaglobinopathy) and ischaemic stroke are reported. The stroke involved the internal carotid artery territory in one and the brainstem in the other. A review of the literature is presented to suggest that the association of sickle cell trait and cerebral infarction is more than coincidental. Haemoglobin electrophoresis should be undertaken routinely in young subjects with ischaemic stroke.

Adolescent↗

Pyogenic cervical vertebral osteomyelitis.

A 54-year-old male with cervical spine osteomyelitis due to haematogenous spread of staphylococcal infection from an intravenous cannula is reported. A review of literature is presented to illustrate the diagnostic difficulties and neurological complications of pyogenic vertebral osteomyelitis.

Catheterization↗

Neuroleptic malignant syndrome in a girl without psychosis.

We report a successfully managed case of neuroleptic malignant syndrome in which the diagnosis was delayed by one week because of the absence of an established psychiatric disease. A high degree of clinical suspicion must be maintained if the diagnosis of this rare, curable but often fatal, complication of neuroleptic therapy is not to be missed.

Adolescent↗

Electrophysiologic evaluation for carpal tunnel syndrome in patients with angioaccess for haemodialysis.

The corrected distal motor latency along the median nerve in 50 upper limbs with the forearm Cimino-Brescia fistula for haemodialysis, when compared to that of the contralateral limb and the control value, showed no evidence of carpal tunnel syndrome (CTS) ascribed to angioaccess. Haemodialysis-associated CTS seems to be related to the predisposing factors, rather than the haemodynamic effects of the arteriovenous fistula or dialysis.

Adolescent↗

Conjugal motor neurone disease.

The occurrence of motor neurone disease (MND) in a Libyan couple who lived together for 40 years and in whom the disease developed within a 15-month period is reported. This is believed to be the second documentation of conjugal MND in the English literature.

Aged↗

A clinical, epidemiological and genetic study of hereditary motor neuropathies in Benghazi, Libya.

A 4-year-search for spinal muscular atrophies (hereditary motor neuropathies, HMN) in Benghazi, Libya, yielded a total of 24 patients, among whom 18 were index cases. This group comprised 6 acute infantile, 12 chronic childhood, and 3 each with adult-onset proximal, and distal forms of the disorder. Distal HMN constituted 12.5% of the total cases. The crude average annual incidence of acute infantile HMN was 0.3/100,000 total population and 1/12,500 births in Benghazi. The crude prevalence rates of chronic childhood, adult-onset proximal, and distal types of HMN were 2.3, 0.6, and 0.6/100,000 respectively. The segregation ratios, 0.26 for acute infantile HMN and 0.24 for chronic childhood HMN, suggested autosomal recessive inheritance. The consanguinity rates among parents of cases and the population did not differ significantly.

Acute Disease↗

Descriptive epidemiology of some rare neurological diseases in Benghazi, Libya.

During a 4-year study period, January 1983 to December 1986, 24 patients (18 index cases) with spinal muscular atrophy (hereditary motor neuropathy, HMN), 9 with myasthenia gravis (MG), 6 with progressive supranuclear palsy (PSP), and 5 with subacute sclerosing panencephalitis (SSPE) were diagnosed in Benghazi. The HMN group comprised 6 acute infantile, 12 chronic childhood, and 3 each with adult-onset proximal, and distal forms of the disease. The crude average annual incidence of acute infantile HMN was 0.3/100,000 total population and 1/12,500 births in Benghazi. The crude prevalence rates of chronic childhood, adult-onset proximal, and distal types of HMN were 2.3, 0.6 and 0.6/100,000, respectively. The larger family size and the high rate of consanguineous marriages contribute to the high frequency of HMN in the study area. Distal HMN constituted 12.5% of the total cases. The adjusted average incidence of MG was 4.4/million/year, 2.1 for males and 6.8 for females. The female:male incidence ratio was 3.2:1. The crude average annual incidence rates/million inhabitants for PSP asnd SSPE were 3 and 2.4, respectively. The frequency of occurrence of SSPE among the subtropical Arab community under investigation is comparable with other surveys from the Middle East and Mediterranean region.

Adolescent↗

Clinical and epidemiological study of Bell's palsy in Benghazi, Libya.

An intensive search for 2 years for patients with Bell's palsy, conducted through the polyclinics, university hospitals and physiotherapy centres in Benghazi, revealed a total of 242 cases. The average annual incidence per 100,000 population was 23.35 and the age-adjusted incidence 35.72. The incidence increased with age up to the sixth decade. Seasonal clustering was noted in the months of December and January. Hypertension and diabetes mellitus were associated in 4.1% and 7% of patients, respectively. Only four patients presented during pregnancy. Recurrent facial paralysis was encountered in 5.4% of patients and was characterized by male preponderance and a tendency to recur more frequently on the same side as the initial paralysis. Familial incidence and bilateral involvement were rare features. Twelve per cent of patients who were followed up had moderate to severe residual weakness.

Adolescent↗

Descriptive epidemiology of selected neuromuscular disorders in Benghazi, Libya.

A 3-year intensive search for selected neuromuscular disorders in Benghazi, yielded 34 patients with Duchenne's muscular dystrophy (25 index cases), 19 with limb-girdle muscular dystrophy (13 index cases), 4 with facioscapulohumeral muscular dystrophy (3 index cases), 3 with opthalmoplegia-plus (all index cases), 13 with polymyositis, 41 with hereditary motor and sensory neuropathy (HMSN) (17 index cases) and 27 with Guillain-Barré Syndrome (GBS). The age-adjusted prevalence rates, on 31 December 1985, per 100,000 population were 6 for Duchenne dystrophy, 3.7 for limb-girdle dystrophy, 0.8 for facioscapulohumeral dystrophy, 0.6 for opthalmoplegia-plus and 7.9 for HMSN (6.4 and 1.5 for Types I and II, respectively). The adjusted average annual incidence of polymyositis was 8.8/mill population; the peak incidence was observed in females in the age-group 20-40. A mean age-adjusted incidence rate for GBS of 1.7/100,000 population per year has been found. The peak age-specific incidence of GBS occurred in the third decade; the sex-dependent difference in the incidence was not significant. No indigenous forms of the disease were encountered and the clinical features differed little from the descriptions in literature. The large family size and high rate of consanguineous marriages contribute to the high frequency of familial disorders, especially those with autosomal recessive inheritance.

Adolescent↗