Biomedical subjects
Publications and source records attributed to G Rao.
CT has proved a useful adjunct to the clinical examination in the differential diagnosis of chorea in adults. The CT abnormalities in cases of Huntington's disease are compared with those of a pathologically verified case of Huntington's disease cut in the CT scan plane of tomography. Relative measurements of caudate atrophy on CT agree well with atrophic processes noted neuropathologically.
The role of contrast-enhanced computed tomography (CT) was evaluated in three nonhuman primates with a severe cerebrovascular insult and resulting elevated intracranial pressure and diffuse circulatory arrest. In all three animals the brain vasculature did not opacify after the bolus intravenous injection of iodinated contrast media. In addition, the brain substance did not enhance although the arterial blood enhanced normally after inhalation of a high concentration of xenon. Xenon-enhanced CT scanning, like 133Xe radionuclide scanning, may be used to define the absence of generalized cerebral perfusion.
Patients with major hematologic disorders who have hypersplenism and alterations in their immune mechanism are subject to a higher incidence of bacteremia after embolization procedures. In certain instances, these infectious complications can be fatal. Medical splenectomy for hematologic disorders is sometimes complicated by massive splenic infarction and spontaneous rupture; spontaneous rupture appears to be a function of both infarct size and underlying infectious complications. Prophylactic measures can be employed to avoid these complications after interventional splenic embolization.
A method of automatic exposure termination (AET) for xeromammography has been devised, significantly reducing the rate of repeat exposures due to poor choice of manual exposure factors. AET images are of good quality and are reliably produced. The concept of AET is based on the existence of an optimal transmitted exposure to the selenium plate, which is easily determined experimentally. In routine clinical xeromammography, a repeat rate of 20% was eliminated by the use of AET.
Superior vena cava syndrome developed in 4 of 1,000 patients in whom a transvenous pacemaker had been implanted. In all cases, endocardial leads were inserted through the cephalic vein and positioned at the apex of the right ventricle. The classical signs and symptoms of superior vena cava hypertension were observed from two weeks to one year after implantation, and the diagnosis was confirmed by cavography. Symptoms resolved following heparin therapy and long-term anticoagulation.
The effect of a mixture of nitroblue tetrazolium (NBT) and vitamin E on the metabolism and ultrastructure of polymorphonuclear leukocytes (PMN) from normal subjects or patients with chronic granulomatous disease (CGD) was determined in vitro. Increasing concentrations of NBT and vitamin E progressively decreased rates of oxygen consumption and 1-14C-glucose oxidation by normal PMN stimulated with particulates to a degree that exceeded either agent alone. NBT-vitamin-E also inhibited vacuole formation and the cytochemical release of myeloperoxidase-positive granules. The depressed oxidative metabolism and degranulation of NBT-vitamin-E-treated control PMN closely approximated the blunted responses of CGD PMN which were similar alone or in the presence of NBT-vitamin-E. In contrast to these effects, the highest concentration of NBT-vitamin-E used in the study did not damage, decrease rates of unstimulated oxidative metabolism of, or impair ingestion of particulates by control or CGD PMN. NBT and vitamin E impose a state on normal PMN which is remarkably similar to that observed in PMN from patients with CGD.
The case report of an atrial septal defect with right-to-left shunting in an adult following blunt chest trauma is presented. To our knowledge a successfully repaired traumatic atrial septal defect has not been previously reported in the English-language literature.
Improved angiographic techniques have proved that therapeutic embolization is effective in controlling massive hemorrhage in selected sites of the gastrointestinal tract and central nervous system. We have controlled massive hemoptysis in five cases with use of our improved techniques and bronchial artery embolization. Because mortality due to massive hemoptysis in both benign and malignant disease is high, therapeutic bronchial artery embolization is the preferable approach in some cases.
Explore the source record for details and available documents.
Keratomalacia occurred in two cachectic hospitalized patients, each with severe vitamin A-protein deficiency secondary to a lethal disease. Prompt therapy with parenteral and topical vitamin A, protein supplementation, and a soft contact lens restored corneal integrity and prevented visual loss in one patient. Keratinization of the conjunctiva did not occur in either patient. Patients with severe protein deficiency may develop keratomalacia in the absence of a severely decreased serum level of vitamin A.
A controlled clinical study was carried out to decide whether the pericardium should be left open or closed after open-heart operations. One hundred patients had the pericardium closed with interrupted silk, another 100 had the pericardium left open. Complications were alike except for the more frequent occurrence of a pericardial rub in the closed group (14 vs 3 patients), though the incidence of post-pericardiotomy syndrome was equal. There was no late tamponade. Two early reexplorations for bleeding were done in the open group, none in the closed. There were no postoperative deaths. In the patients who consented to postoperative angiography following revascularization procedures, the incidence of graft failure was equal in both groups. The pericardium should be closed after an open-heart operation. Morbidity and mortality are unchanged, and repeat cardiac exploration is safer.
The pattern of peripheral vascular disease in India was studied in 89 patients undergoing amputation for vascular insufficiency. A control group of 26 limbs was studied for aging changes. Clinically, cases were classified into TAO (25), ASO (54) and thrombo-embolic disease (10). Angiographic, macroscopic and microscopic study of dissected vascular tree was done in view of clinical diagnosis. No significant difference was noted in the frequency and extent of involvement of limb arteries in TAO and ASO. Histologically angiitis was noted in 4 cases of TAO and one of ASO but these did not form a distinct clinical group. Primary thrombotic occlusion was seen in 21 cases of TAO and 23 cases of ASO. Atheroma with and without thrombosis was found in 26 cases. In 4 cases the arterial tree was normal. Atheromatous lesions were not seen in control group. In the groups under study they were thought to represent old thrombi rather than degenerative lesions predisposing to thrombosis. In view of these findings it was felt that Buerger's disease was primarily a thrombotic disorder. Angiitis was rare and was probably secondary. The two clinical groups TAO and ASO are not pathologically distinct as very high percentage of the latter showed primary thrombosis. The genesis of thrombosis in two groups however may be different.
Fatal pulmonary embolism is a common complication of any major surgery, especially in high risk patients. Experimental work in animals showed definite impairment of myocardial function after inferior vena caval ligation, but no changes after clipping. During the last four years, we have used concomitant vena caval clipping as a prophylactic measure in major abdominal vascular procedures. No added mortality or morbidity has occurred because of clipping per se and no deaths were due to pulmonary embolism. We recommend concomitant prophylactic clipping as an adjunctive procedure for all laparotomy patients who are prone to pulmonary embolism.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.