Showing papers on "Cerebral Revascularization published in 1981"

Reversal of focal "misery-perfusion syndrome" by extra-intracranial arterial bypass in hemodynamic cerebral ischemia. A case study with 15O positron emission tomography.

Abstract: Tomographic images of cerebral blood flow (CBF) and oxygen extraction fraction (OEF) using the 15O continuous inhalation technique, and positron emission tomography, were obtained from a patient with cerebral ischemia distal to an occluded left internal carotid artery. There was a focal mismatch between CBF and oxygen metabolism in the brain supplied by the middle cerebral artery where CBF was decreased and OEF increased ("misery-perfusion syndrome" as opposed to "luxury-perfusion syndrome"). These abnormalities were most marked in the parieto-occipital watershed area. After left superficial temporal to middle cerebral artery anastomosis, the clinical attacks ceased and a repeat study did not demonstrate the previous CBF and OEF abnormalities. This suggests that this pattern of abnormalities indicates potential viable tissue. The concept of "misery-perfusion" may be of some importance in the pathophysiological mechanisms of hemodynamic cerebral ischemia and serve as a rational basis for revascularization procedures.

Chronic common carotid occlusion.

Abstract: Twelve patients with chronic common carotid artery (CCA) occlusion were studied. There were 8 patients with TIAs (3 hemispheric and 5 vertebral-basilar), one with a completed stroke, and 3 were asymptomatic. The ipsilateral internal carotid artery (ICA) was confirmed patent in 6 patients at the time of operation, although angiograms had demonstrated patency in only two. The ipsilateral external carotid artery (ECA) was patent in all but one patient. Arterial reconstructions were done on 7 patients. The carotid bifurcation was revascularized by subclavian-to-carotid bypass grafts in 5 patients, 3 with vertebral-basilar (V-B) TIAs, one with hemispheric TIAs, and one with a completed stroke. Vertebral revascularization was done on 2 patients, one with V-B TIAs and one who was asymptomatic. All revascularized patients had satisfactory results. Symptomatic patients can be treated by cerebral revascularization through either the ICA, if patent, the ECA via the ophthalmic collaterals, or through the vertebrals when hypoperfused. The ICA is preferentially revascularized and exploration often reveals a patent ICA that was not visualized angiographically. Recently, directional Doppler studies have proved useful in determining ICA patency.

Recurrent retinal ischemia beyond cervical carotid occlusions Clinical-angiographic correlations and therapeutic implications

Abstract: Seventeen patients with persistent amaurosis fugax ipsilateral to angiographically documented internal carotid artery (ICA) occlusions in the neck have been treated by the authors over the past 5 years. Complete cerebral arteriography in each case demonstrated that the symptomatic ophthalmic artery was perfused exclusively by the ipsilateral external carotid artery (ECA), which invariably had an obstructive and/or ulcerative lesion and its origin, and/or an adjacent residual "stump" of the occluded ICA. In nine patients, retinal artery branch emboli were visible on funduscopy. One patient had angiographic evidence of intracranial embolization via the ophthalmic artery from the ECA. Although ipsilateral superficial temporal-muscle cerebral artery anastomosis in one patient, and endarterectomy of a contralateral carotid stenosis in another patient, failed to relieve symptoms, endarterectomy of the ECA with resection of the "stump" of the occluded ICA effectively terminated symptoms in 10 of 11 patients. Anticoagulant drug therapy promptly abolished symptoms in four nonsurgical patients as well as in two patients with failed operations. It is concluded that recurrent retinal ischemia beyond cervical carotid occlusions frequently results from microembolism via the ipsilateral ECA. Patients with this mechanism of postocclusion recurrent ischemia can be identified on the basis of clinical history, ophthalmological examinations, and complete cerebral arteriography. Termination of embolic phenomena should be the major treatment goal in these individuals, and ECA endarterectomy is recommended. Anticoagulant drugs are an effective alternative treatment in patients who are poor surgical risks.

Delayed thrombosis of synthetic microvascular bypass grafts.

Abstract: A 3-mm-diameter synthetic polytetrafluoroethylene (PTFE) cervical carotid bypass graft 20 cm in length was implanted in 30 dogs for the evaluation of blood flow, tissue response, and patency at intervals of 1 to 120 days. Although 4 of 5 grafts removed after 5 to 8 days were patent (80%), long term patency was observed in only 1 graft (10%). Aspirin treatment did not influence patency. Scanning electron microscopy demonstrated the lack of a neoendothelial layer upon the luminal surfaces of patent grafts, which were covered with a fibrin-blood cell lining. Subintimal fibrosis resulted in stenosis at sites of anastomosis in thrombosed grafts. The graft length, its small caliber, and a 40% decrease in blood flow after implantation may have contributed to thrombosis of the bypass graft in this model. Synthetic PTFE microvascular grafts may not be suitable for clinical use in extracranial-intracranial arterial bypass surgery.

[Cerebral arterial occlusive disease in children -- clinical aspects and surgical treatment (author's transl)].

Abstract: In the present study the pathology and treatment of occlusion of cerebral arteries in children were investigated in an attempt to find out an approach to the surgical treatment of cerebral arterial occlusive disease of childhood. We had a total of 55 children with cerebrovascular disorders seen at our Institute during the past 11 years. In this series there were 19 cases of cerebral arterial occlusive disease. The causes in 15 cases of cerebral arterial occlusive disease except for moyamoya disease were heart disease in 7 cases, trauma in 2 cases and unknown in 6 cases. The cerebral arterial occlusive disease had its onset at the age of less than 6 years in 12 of 15 cases. The disease began with hemiplegia of sudden onset. The disease onset was also attended frequently by a convulsive seizure, which distinguishes the condition from that in adults. In 10 of all 15 lesions the site of occlusion was in the distribution of the middle cerebral artery. One case in which there was occlusion of the basilar artery occurring in association with trauma was described in detail. In one instance the treatment consisted of STA-MCA anastomosis. Paroxysmal black out attacks, which had been of frequent occurrence in addition to hemiplegia were relieved postoperatively. In our opinion, STA-MCA anastomosis for cerebral arterial occlusive disease in children should be considered to be indicated only when 1) cerebral angiographic evidence of occlusion or stenosis of a trunk of cerebral artery is still present after the acute stage or 2) no extensive low density area is demonstrable on CT scan. Surgery is generally less indicated in those instances in which the occlusion is due to embolism. However since abscess may arise from such an arterial lesion, surgery should be considered, or at least its feasibility be evaluated, whenever 1) the underlying cardiac pathology well permits surgical intervention and 2) half a year has passed since an initial attack.

Extra-intracranial anastomosis using a venous graft.

Abstract: The authors describe a patient with ischaemic neurological incidents due to bilateral hypoplasia of the carotids. Because the use of the superficial temporal artery or the occipital artery was impossible, the extra-intracranial anastomosis was performed by a direct venous graft between the external carotid artery and the posterior temporal artery. The authors describe and illustrate the operation, emphasizing the particular difficulties due to differences in diameter of the arteries and the graft. Because postoperative control angiography demonstrated perfect permeability of the anastomosis, this technique is suggested for when a normal branch of sufficient diameter of the external carotid artery cannot be used.

Surgery for stroke.

Abstract: In spite of these criticisms the woman who has breast cancer is now more aware that breast reconstruction is a possibility after mastectomy. Only if the general surgeon and, when applicable, the radiotherapist give full consent should a woman be considered for reconstruction. Patients of widely varying clinical stages are considered suitable. Even women with disease beyond stage II have been referred by some protagonists for reconstruction on the basis that, although survival may be limited, the quality of survival for that particular patient can be enhanced by reconstruction a very personal stance that in the patient's interest is not unjustifiable. Preparation of the patient for breast reconstruction must occupy more time than is usually allotted in the outpatient department. Whether immediate or delayed reconstruction is planned, she should know what this implies in terms of scars and have an idea of the final results from photographs. Discussion with a woman who has completed the sort of reconstruction planned for the particular patient is the best solution (an added role of the Mastectomy Association). Any continuing reservations or doubts expressed by the patient should exclude her from reconstruction. Unless wholly committed, she is likely to be disheartened by the hospitalization and final result. Reconstruction of the breast after mastectomy is invaluable for certain patients whose quality of life is otherwise seriously diminished. Only by liaison between the general surgeon, the radiotherapist and the reconstructive surgeon, assisted, as appropriate, by the general practitioner and the psychiatrist, can these patients be properly helped and useful guidelines and prognostic features elucidated. Furthermore, it is possible that if the public were more completely informed, those women for whom the dread of mastectomy is greater than the fear of cancer itself would seek earlier treatment. eM Ward Consultant Plastic Surgeon West Middlesex Hospital. 1sleworth

The precise technique of end-to-side microvascular anastomosis with a suitable experimental model.

Abstract: In order to perform extracranial to intracranial microrevascularisation a good end-to-side microvascular anastomosis technique is the first essential. The rabbit femoral vessels are similar in size to the human cortical branches of the middle meningeal artery and superficial temporal artery and an easy technique of end-to-side anastomosis of these vessels is described. This pays particular attention to proof of patency until the last stitch is applied. Assessment of patency in all three directions is checked by the directional Doppler or the electromagnetic flow probe.