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T V Holohan

Publications and source records attributed to T V Holohan.

9 recordsLinked to original sources

Extracranial-intracranial bypass to reduce the risk of ischemic stroke.

Extracranial-intracranial (EC-IC) bypass surgery is an operative procedure in which the superficial temporal artery is anastomosed to the middle cerebral artery. The operation, first described in 1969, was employed to circumvent otherwise surgically inaccessible atherosclerotic lesions high in the internal carotid system or in the middle cerebral artery. This assessment compares the findings from 13 surgical series of EC-IC bypass (1464 patients) with those reported in the only prospective, randomized, cooperative trial of this procedure (1377 patients). Analysis of the outcomes in the 1464 patients included in the surgical series produced insufficient evidence to support a conclusion that post-EC-IC bypass stroke rates were lower than the rates of either the medically or surgically treated groups in the controlled clinical trial. In the absence of reliable, objective evidence of the existence of a group of patients in whom surgical intervention is superior to medical treatment in reducing the frequency of stroke, the results of the single controlled clinical trial, which demonstrated no benefit of bypass, must be accepted as the best evidence currently available.

Brain Ischemia

Extracranial-intracranial bypass to reduce the risk of ischemic stroke.

Extracranial-intracranial bypass surgery is an operative procedure in which the superficial temporal artery is anastomosed to the middle cerebral artery. The operation, first described in 1969, was employed to circumvent otherwise surgically inaccessible atherosclerotic lesions high in the internal carotid system or in the middle cerebral artery. This assessment compares the findings from 13 surgical series of EC-IC (1,464 patients) with those reported in the only prospective, randomized, cooperative trial of this procedure (1,377 patients). Analysis of the outcomes in the 1,464 patients included in the surgical series produced insufficient evidence to support a conclusion that post-EC-IC bypass stroke rates were lower than the rates of either the medically or surgically treated groups in the controlled clinical trial. In the absence of reliable, objective evidence of the existence of a group of patients in whom surgical intervention is superior to medical treatment in reducing the frequency of stroke, the results of the single controlled clinical trial, which demonstrated no benefit of bypass, must be accepted as the best evidence currently available.

Brain Ischemia

A prospective randomized trial of HLA-matched versus mismatched single-donor platelet transfusions in cancer patients.

The use of histocompatability antigen (HLA)-matched platelets has been advocated for the support of thrombocytopenic cancer patients. We randomized 78 newly diagnosed cancer patients prospectively (before thrombocytopenia) to receive either HLA-matched or mismatched single-donor platelet transfusions. Three hundred forty-one platelet transfusions were given for 80 separate episodes of therapy-induced thrombocytopenia in 33 patients. Forty-five patients receiving intensive chemotherapy did not develop significant (less than 20,000 platelets/mm3) thrombocytopenia and did not receive a platelet transfusion. No marked difference was observed between the matched and mismatched groups in regard to number of total platelet transfusions per patient (median, 3 vs. 5, respectively; P = 0.076), number of platelet transfusions per episode (median, 3.0 vs. 3.5, respectively; P = 0.28), or days between transfusions (median, 2 vs. 2, respectively, P greater than 0.4). Bleeding episodes, although rare, tended to be of increased severity in the mismatched group. Febrile patients receiving mismatched platelets tended to have a lower posttransfusion increment increase than their nonfebrile counterparts (P = 0.068), although a similar trend could not be demonstrated between febrile and nonfebrile patients who received matched platelets (P = 0.22). Patients treated as outpatients had significantly higher posttransfusion increments than when transfused as inpatients when they were given mismatched platelets (P less than 0.0005). Development of antiplatelet antibody did not appear to affect response to platelet transfusions. Only one patient developed sustained high-level antibody titers. In patients where thrombocytopenia was significant, the transfusion of HLA-matched platelets did not appear to offer a significant advantage. However, HLA-matched platelet transfusions tended to be associated with higher posttransfusion increments in febrile patients and a trend toward fewer severe bleeding episodes. A multi-institution trial containing a large number of patients is needed to evaluate trends observed in this study.

Adolescent

High-performance affinity chromatography: a rapid technique for the isolation and quantitation of IgG from cerebral spinal fluid.

Standard techniques for the quantitative measurement of IgG in cerebral spinal fluid take up to 24 hs. This often delays diagnosis and treatment, critical in newborn infants. A high-performance affinity chromatography (HPAC) column, containing immobilized anti-IgG antibody, produced the same or better results in 1 h. The HPAC system gave a 98% correlation with the standard techniques at the normal-abnormal IgG level, but was more accurate at the extremely low IgG level.

Cephalometry