Biomedical subjects
Publications and source records attributed to V V Radhakrishnan.
A very unusual case of sellar-sphenoid sinus hemangioblastoma without stigmata of von Hippel-Lindau disease is presented. Subtotal excision of tumor was done via an extended frontobasal approach. Diagnostic controversies between hemangioblastoma and angioblastic meningioma are discussed and the relevant literature reviewed.
A 10-year-old girl underwent radical decompression of a right temporal tumour extending to the insular cortex which proved to be a differentiated ganglioglioma. One year later, she presented with a bleeding right frontal tumour extending to the insula, the histology of which showed it to be the anaplastic variant of ganglioglioma. She underwent postoperative radiotherapy but died 6 months after the second operation. Anaplastic ganglioglioma is a rare variant of ganglioglioma and progression of the latter to anaplastic ganglioglioma is an extremely rare occurrence. The literature regarding ganglioglioma is reviewed.
Mitochondrial myopathies are heterogeneous group of clinical disorders that can affect multiple systems besides skeletal muscles. The mitochondrial abnormalities in the skeletal muscles are morphologically identified by the presence of characteristic Ragged-red fibers (RRF) in the cryostat sections of the muscle stained with modified Gomori's trichrome stain. In this retrospective study, clinical and histopathological features in six patients with mitochondrial myopathies have been analysed. The utility of histochemical methods in confirming the diagnosis of mitochondrial myopathy has been emphasised.
The authors report a case of suprasellar meningioma that developed 16 years after surgery and radiation therapy for a pituitary adenoma. The patient had significant recovery of visual loss following excision of the meningioma. We believe that this tumor was induced by radiation received by the patient previously and we stress that tissue diagnosis should be obtained in patients who develop a recurrent tumor after a long period following initial radiotherapy. Radiation induced meningioma has to be considered in the differential diagnosis of any patient who has a recurrence after therapeutic radiation. This is especially essential in the absence of biochemical and clinical signs of a previously functioning pituitary adenoma and before the initiation of medical therapy for recurrent pituitary adenomas.
The EEG of a 12-year-old girl with stage II subacute sclerosing panencephalitis (SSPE), who had also suffered from a non-progressive mental retardation of unknown aetiology since early childhood, revealed periodic generalised stereotyped fast wave bursts synchronous with myoclonic jerks. The background activity was nearly normal. The diagnosis of SSPE was established by raised serum and measles antibody titres, raised CSF IgG, and brain biopsy. This rare type of periodic complex has only once been described in the literature, again in a mentally retarded child who had developed SSPE. We suggest a mechanism of origin of this type of periodic complex drawn from observations in these two cases, and discuss its significance.
Granular cell tumours of the neurohypophysis are uncommon and only 30 cases are documented in the literature till 1994. In this communication, the salient clinical and histomorphological features in two patients with granular-cell tumour of the neurohypophysis are described.
Dysembryoplastic neuroepithelial tumour (DNT) of the central nervous system is a recently recognized entity. We describe the clinical and characteristic histomorphological features in a patient with DNT. As this lesion carries a favourable prognosis, it becomes essential to make an accurate histopathological diagnosis.
In this study, clinical, histopathological and immunological profiles were analysed in ten patients with inflammatory myopathies. Polymyositis and dermatomyositis were more common than other forms of inflammatory myopathies. The pathogenetic mechanisms and distinguishing histopathological and immunological profiles between polymyositis and dermatomyositis have been highlighted.
We report three cases of enterogenous cyst, one craniospinal and two spinal manifesting with features of spinal cord compression. In one the cyst was intramedullary in location and in the other two it was intradural, extramedullary. The unusual clinical presentation, location and magnetic resonance imaging (MRI) characteristics are discussed. None of the three patients had any vertebral anomaly or other congenital malformation. All patients had excellent outcome following surgery.
In guinea-pigs, myocarditis was induced under experimental conditions by immunizing the animals with rabbit skeletal muscle myosin-beta. The salient histopathological features were foci of perivascular lymphonononuclear aggregates, necrosis, and degeneration of myocardial cells. Antimyosin-beta antibodies in the immune complexes were demonstrated in the sera of the guinea-pigs. An immune-complex-mediated tissue-injury is proposed in the pathogenesis of myocarditis.
Gangliogliomas are one of the uncommon tumours of central nervous system. Since these tumours have been associated with an indolent clinical course and benign biological behaviour, it is essential to make an accurate histopathological diagnosis of ganglioglioma. In this study the salient clinical and histopathological features in six patients with intracranial ganglioglioma are described.
Gliomatosis cerebri is a vary rare neoplastic lesion of the central nervous system. An intra-vitam diagnosis of gliomatosis cerebri can be suggested with a steleolactic biopsy of the lesion in conjunction with Magnetic Resonance Imaging (MRI) findings in the brain.
Explore the source record for details and available documents.
Antibodies to two mycobacterial antigens viz - culture filtrate antigen (CFA) and Mycobacterium tuberculosis antigen 5 were raised in rabbits. Enzyme-linked immuno sorbent assay (ELISA) and immunoblot methods were used for the evaluation of the specificity of the rabbit antibodies to M. tuberculosis. Immunoblot method is more sensitive than ELISA for the detection of antibodies to M. tuberculosis in the rabbit sera. It is being emphasised that characterisation of the mycobacterial antigens and evaluation of the specificity of the antimycobacterial antibodies are essential prior to their applications as an adjunct in the laboratory diagnosis of human mycobacterial disease.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
In this study, thirty-two non-functional and eighteen functional pituitary adenomas were analysed for the presence of argyrophilic nucleolar organizer regions (Ag-NORs) in paraffin sections, using an one-step silver-colloidal staining method. Differences in the mean Ag-NOR numbers of functional pituitary adenomas were statistically significant than those of non-functional pituitary adenomas. It is being emphasised that evaluation of Ag-NOR count is a more reliable index than the presence of mitotic figures in predicting the proliferative activity as well as possibility of recurrence in a patient with pituitary adenoma.
In order to define the mycobacterial antigens that may be specifically associated with human tuberculous infection, the cerebrospinal fluid (CSF) specimens of 30 patients with tuberculous meningitis (TBM) and of an equal number of patients with non-tuberculous meningitis (controls) were compared by means of an immunoblot method for detecting antibody to Mycobacterium tuberculosis. In the CSF of controls, mycobacterial antibody was either absent or, when present, was found to react with 27, 30 and 45 KDa antigens of M. tuberculosis. Among patients with TBM, the numbers as well as intensities of the immunostained bands in the nitrocellulose membranes (NCM) were greater than among controls. Furthermore, a unique disease-associated mycobacterial antigen, 35 KDa of M. tuberculosis, was found to react with a specific antibody in the CSF of patients with TBM but was not detected in the CSF of any of the controls. This 35 KDa antigen could be easily identified in the NCM. The immunoblot method showed 100% sensitivity in all the culture-positive patients with TBM. Because of the high degree of specificity as well as sensitivity of the immunoblot method, we consider that this method is of value for confirming the diagnosis of TBM.