PubMed Health⌕ Search

Biomedical subjects

W Ballinger

Publications and source records attributed to W Ballinger.

11 recordsLinked to original sources
PubMed1986

Small particle polyvinyl alcohol embolization of cranial lesions with minimal arteriolar-capillary barriers.

Polyvinyl alcohol foam, prepared as small particles measuring 70-150 micron when injected in intracerebral arteries of the rat, adhere to the vascular endothelium, allowing the particles to be captured without necessarily wedging intraluminally. Based on this observation, small particle microembolization was performed in a series of patients who had hypervascular cranial lesions, whose matrices angiographically appeared to have at best minimal arteriolar-capillary barriers. Each case was associated with intracranial dural sinus or cerebral venous drainage. In addition, several lesions had either venous ectasia or venous aneurysms. Symptomatic improvement occurred in all cases without apparent neurologic or pulmonary complications. These examples demonstrate the ability of very small polyvinyl alcohol foam particles to remain within the interstices of vascular lesions that display evidence of only minimal arteriolar-capillary barriers.

Adult↗
PubMed1983

The effect of peripheral lymphoid cells on the incidence of lethal graft versus host disease following allogeneic mouse bone marrow transplantation.

Experiments were performed to study the role of circulating lymphoid cells in the incidence of lethal graft versus host disease (GVHD) in radiation-induced fully allogeneic mouse chimeras. The incidence of GVHD was reduced significantly in BALB/c leads to C57BL/6 radiation chimeras if bone marrow donors were exsanguinated immediately prior to marrow harvest. Chimeras resulting from the injection of bone marrow from bled donors exhibited only donor cells in spleen, bone marrow and peripheral blood and normal levels of Thy 1+ and Ia+ cells were found in each of these lymphoid compartments. The addition of as few as 3 X 10(4) peripheral mononuclear cells to the marrow from exsanguinated donors uniformly led to lethal GVHD. 51Cr-labeled cell traffic studies revealed that prior exsanguination of marrow donors led to about a 70% reduction in the number of circulating mononuclear cells contaminating the bone marrow at the time of marrow harvest. This decrease in contaminating peripheral cells was calculated to be in the appropriate range to account for the decreased GVHD seen when marrow from exsanguinated donors was used. It thus appears that peripheral cells contaminating marrow can be an important factor in causing lethal GVHD in allogeneic radiation chimeras. These results raise the possibility that the fulminant GVHD seen in human marrow transplantation is in part due to the major contamination of bone marrow with peripheral blood that results from the techniques currently used for human bone marrow harvest.

Animals↗
PubMed1983

Hemorrhage into pituitary adenomas.

The clinical and pathologic features of pituitary apoplexy were evaluated within the last 100 consecutive pituitary tumors surgically treated at this institution. From this group, ten tumor specimens exhibited pathologically verifiable hemorrhagic necrosis, including six with classic apoplectic onset; the hemorrhage in four patients was asymmetric. The tumors of symptomatic patients were large, with suprasellar and parasellar extension readily identifiable by neuroradiologic examination. All tumors within this group were chromophobic adenomas by light microscopy, and each of these tumors microscopically exhibited a sinusoidal arrangement with very prominent vascularity. Comparatively, those tumors with asymptomatic hemorrhage were all intrasellar and were encountered in younger patients who had exhibited prior endocrine disturbances. By light microscopy, two of these asymptomatic lesions were chromophobic and two were acidophilic adenomas. In contrast with larger tumors, however, increased vascularity or sinusoidal patterns were not a prominent feature within this group. Our experience suggests hemorrhage within pituitary tumors is a common event, but symptomatic bleeding generally occurs in older patients whose larger tumors contain a pathologic vascular predisposition. Urgent surgical decompression (usually transsphenoidal) in symptomatic patients produced great neurologic improvement in each case.

Adenoma↗
PubMedDate not supplied

Latex vascular occlusion balloons: histopathologic evaluation in a high-flow aortocaval fistula model.

The treatment of carotid-cavernous fistulae with intravascular, detachable latex balloons has become an accepted method. However, the histologic changes associated with such balloon embolization in a high-flow fistula state have not been described. This study evaluated the microscopic findings in a series of 12 rats studied over a 3-month period using an aortocaval fistula model. Small latex balloons were introduced into the venae cavae of rats in whom aortocaval fistulae had been surgically created 3 weeks earlier. The histopathologic changes associated with treatment of these fistulae were examined at 1, 2, 4, 6, 8, and 12 weeks. These changes can be characterized by an acute phase with thrombus formation and acute inflammation, followed by intermediate (or subacute) and chronic phases with diminishing inflammation and progressively increasing fibrosis of the fistula site. The latex balloon became encased by the fibrotic reaction but remained nonadherent and was easily removed at every study interval. No abscess formation or persistent vasculitis was apparent, and foreign-body giant cell reaction was minimal. Closure of the high-flow fistula site required the balloon to remain inflated for at least 7-9 days.

Animals↗
PubMedDate not supplied

High-flow, aortocaval fistulae: radiologic and histopathologic evaluation in a rat model.

An animal model for a high-flow, aorta-to-vena cava fistula has been developed using microsurgical techniques in the rat. This model provides a means for histopathologic and angiographic evaluation of the natural evolution of major vessel, artery to vein fistulae. Data obtained from such a model may have relevance to the successful treatment of high-flow, head and neck fistulae using detachable intraarterial occlusive balloons. This microsurgical technique is unique, since it requires no intervening sutures or graft material that would alter the histopathologic process. After a series of such aortocaval fistulae were created, serial histologic and angiographic features were elucidated for intervals between 1 day and 6 months. Three stages of evolution are noted including: an initial hemorrhagic dissection phase; a subacute phase where organization of the thrombus and actual formation of a fistulous tract occurs; and a chronic phase characterized by pseudoaneurysm formation, arterialization of the vena cava, and proximal vasodilatation of the aorta.

Animals↗