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Biomedical subjects

R H Patterson

Publications and source records attributed to R H Patterson.

At least 55 records · Page 3Linked to original sources
PubMed1981

Role of platelets in vasogenic brain edema. I. Significance of thrombus formation in the damaged vessels.

In an investigation of the role of platelets in vasogenic edema in cats, direct observation of the cortex revealed that within several minutes after cold injury, platelet thrombi formed in small veins at the point where the veins emerged from the depths of the brain. Later, edema fluid extravasated from the veins at this same point. Pretreatment with a platelet inhibitor, RA-233, abolished the formation of platelet thrombi and remarkably enhanced the leakage of edema fluid. The microcirculation was assessed by carbon black perfusion and was found to fill better in the cats that received the platelet inhibitor. The better filling may be ascribed to a decreased number of thrombi and consequent improved blood flow in small blood vessels. We conclude that platelet aggregates play a major role in controlling the leakage of edema fluid after cold injury.

Animals↗
PubMed1981

Role of platelets in vasogenic brain edema. II. Contribution of platelet serotonin in brain edema.

In this study of the function of platelets after CNS injury, platelets were treated with serotonin labeled with radioactive carbon (14C) in animals subjected to a freezing lesion of the cerebrum. The distribution of platelet serotonin was measured by counting the specific activity of 14C-labeled serotonin in tissue and by autoradiography. Some of the animals were treated with RA-233, which inhibits the formation of platelet plugs after endothelial damage and the release of serotonin from platelets. Platelet serotonin accumulated near the surface of the cortex at the site of injury in all animals. More cerebral edema developed in animals treated with the platelet inhibitor than in untreated animals, probably because platelet aggregates were inhibited from forming and were not available to plug leaks in the traumatized vessels. Serotonin did not appear to facilitate the spread of edema.

Animals↗
PubMed1981

Combined transoral and median labiomandibular glossotomy approach to the upper cervical spine.

A surgical approach to the clivus and anterior spine from C-1 to the upper part of C-5 is described. It is a direct approach that provides a wider and longer exposure than does the transoral approach. Despite the seemingly radical incision, the cosmetic deformity and functional loss are minimal. This approach is useful for the surgical treatment of a variety of processes that are situated ventral to the upper cervical spinal cord and the cervicomedullary junction.

Adult↗
PubMed1980

Subungual malignant melanoma: a clinical-pathologic study.

In a study of 66 cases of subungual malignant melanoma, a clinical misdiagnosis often delayed histologic diagnosis and proper treatment. Most subungual melanomas are deep lesions at the time of histologic examination. Female patients have a relatively good prognosis as opposed to the poor prognosis of male patients. Paradoxically, a few patients with relatively shallow tumors and low mitotic rates died with metastases and a few patients with deep aggressive-appearing melanomas are alive and well more than five years later. Metastases, however, may become evident many years after the primary tumor has been resected. Metastases to the regional lymph nodes may be found at the time of amputation but do not preclude a long survival. No difference in prognosis related to the extent of the amputation could be identified. A variety of histologic patterns may be present and the adjacent epidermis frequently shows changes of precancerous melanosis but the survival is not affected.

Adult↗
PubMed1980

Surgical removal of craniopharyngiomas by the transcranial approach through the lamina terminalis and sphenoid sinus.

We describe a method of attempting total removal of a craniopharyngioma using a subfrontal approach; dissection of the tumor from the brain stem, hypothalamus, and optic chiasm through the lamina terminalis; and then piecemeal removal of the tumor through the sphenoid sinus. Eleven patients treated by this approach are reported. In these patients, prior subfrontal operation did not affect outcome, but a prior transventricular operation or prior high dose radiation therapy made complete tumor removal less likely. We believe that this operation is one way to remove a craniopharyngioma that affords satisfactory exposure and reduces the chances of injury to the frontal lobes, hypothalamus, and optic pathways.

Adolescent↗
PubMed1976

Cerebrovascular blockade associated with thoracotomy and its prevention with a platelet inhibitor.

Dogs subjected to a thoracotomy in which a rib-spreading retractor was employed developed filling defects in the cerebral microcirculation attributable to obstruction by microemboli. These changes were not observed in control groups and could be prevented in the experimental group by pretreatment with RA233, a platelet inhibitor. It is possible that microembolic-related complications of operations and trauma, such as pulmonary insufficiency, might be ameliorated by the use of platelet inhibitors.

Animals↗
PubMed1976

Transitory cerebral microvascular blockade after cardiopulmonary bypass.

Dogs were submitted to cardiopulmonary bypass (CPB) carried out under conditions calculated to generate large numbers of microbubbles and microemboli. On the day following the procedure the dogs showed evidence of neurological damage including impaired consciousness and ataxia. These abnormalities largely cleared within a week. When the animals were sacrificed at intervals after the procedure, the cerebral microvasculature was demonstrated by injecting a suspension a lamp black into the carotid artery. This revealed that multiple filling defects were present in the microcirculation of the brain immmediately after CPB and for two days thereafter. However, by seven days the microvascular blockade had disappeared, and the vascular blockade had disappeared, and the vascular pattern of the brain had returned to normal. Neuropathological findings were sparse and restricted to the cerebellum. This study suggests that the transient neurological syndromes that sometimes follow cardiopulmonary bypass for heart surgery may be due to a transient microvascular blockade, perhaps by microbubbles and microparticles.

Animals↗
PubMed1976

Hemopericardium, anticoagulation, and an endocardial pacemaker. A case report with description of new auscultatory and radiographic signs.

A case of organizing hemopericardium and cardiac tamponade in a patient with a permanent endocardial pacemaker who was maintained on anticoagulation is presented. The hemopericardium is concluded as solely due to the anticoagulation. A new auscultatory finding attributable to an endocardial pacemaker and a helpful radiographic sign of pericardial effusion in patients with these pacemakers is described.

Cardiac Tamponade↗