Search PubMed⌕ Search

Biomedical subjects

D F Fisher

Publications and source records attributed to D F Fisher.

31 records · Page 2Linked to original sources
PubMed1985

Bright-light amaurosis fugax: an unusual symptom of retinal hypoperfusion corrected by external carotid revascularization.

The eye often serves as an important monitor of carotid artery disease by manifesting visual disturbances before cerebral events. The most typical ocular symptom complex is amaurosis fugax characterized by loss of vision in one eye that occurs suddenly and clears within seconds to minutes. This symptom is a hallmark of carotid artery disease and is usually caused by an embolic event. Although monocular visual disturbance on a hemodynamic basis is a more unusual manifestation of carotid artery disease, significant stenosis in combination with a low-flow state can cause transient, unilateral telescoping of vision. This report describes another visual disturbance associated with carotid artery disease in which unilateral visual loss occurred upon exposure to bright light. We term this syndrome bright-light amaurosis fugax and document successful treatment by external carotid artery revascularization in two patients.

Arteriosclerosis↗
PubMed1984

Dilemmas in dealing with the blue toe syndrome: aortic versus peripheral source.

Six patients with unilateral blue toe syndrome presented a diagnostic dilemma with regard to the source of embolization: central aortic versus peripheral. Two patients had moderately severe aortoiliac atherosclerosis associated with focal stenoses in the superficial femoral arteries, and four patients had mild aortoiliac disease associated with localized plaques confined to either the superficial femoral or popliteal arteries. In all patients, it was elected to explore the peripheral lesions first. At operation, ulcerated plaques or focal stenoses were found, and all lesions had adherent white thrombi on their surfaces. All patients were treated either by localized thromboendarterectomy or short reversed saphenous vein grafting. There was no morbidity or mortality. Recurrent embolization did not occur during a follow-up of 8 to 24 months. Distal atherosclerotic lesions should be sought to explain distal embolization before more complex aortoiliac disease is incriminated. In the presence of concomitant aortoiliac disease, it is mandatory to directly explore the peripheral lesion, open the artery, and carefully examine the lesion in situ. Thrombus adherent to the surface of an ulcerated plaque is evidence of an embolizing source. This approach is associated with minimal morbidity and may be curative. If these findings are not present, it would be appropriate to proceed with staged correction of aortoiliac disease.

Aged↗
PubMed1984

Mandibular subluxation for high carotid exposure.

Twenty-four patients with internal carotid artery lesions extending above the second cervical vertebra underwent mandibular subluxation for additional exposure. The original technique of bilateral arch bar wiring requiring 90 minutes for application has evolved into a circummandibular/transnasal wiring technique requiring approximately 10 minutes. Subluxation of the mandibular condyle 10 to 15 mm anteriorly results in displacement of the mandibular ramus 20 to 30 mm anteriorly. This technique provides a marked increase in exposure of the internal carotid artery up to the base of the skull by transforming a triangular operating field into a rectangular field. The technique is quick, easy to perform, and not associated with objective or subjective temporomandibular joint dysfunction.

Adult↗
PubMed1983

Preoperative disseminated intravascular coagulation associated with aortic aneurysms. A prospective study of 76 cases.

A prospective study of 76 preoperative patients with aortic aneurysms was undertaken to determine the true incidence of associated disseminated intravascular coagulation (DIC). Although 39% of the patients showed a notable elevation of the fibrin split products level, only three had thrombocytopenia and a clinical bleeding diathesis, as well. Thus, clinically overt DIC occurred preoperatively in only 4% of the patients. All three patients had extensive aneurysms that involved the thoracoabdominal aorta. Preoperative fibrinogen levels in this series tended to be high-normal or elevated and were not good indicators of underlying excessive fibrinolysis. Hemostatic abnormalities, such as ecchymoses and petechiae, may be the key to the clinical diagnosis of DIC in preoperative patients with aortic aneurysms.

Aged↗
PubMed1978

Visual recognition memory for binary pictures: another look.

Recognition memory for matrices of 0s and 1s was examined as a function of the number of elements (complexity) and density of those elements within the matrix. It was found that with greater density and lesser complexity, recognition performance improved. This result contradicts an earlier finding of Green and Purohit, who concluded that the more complicated matrices led to better performance. The present study suggests that their conclusion was erroneous and stemmed from failure to control the physical parameters of density and number of elements in the matrix. Implications for the general problem of recognition memory and eye movements are discussed.

Eye Movements↗