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At least 19 recordsLinked to original sources
PubMed1978

Cerebral revascularization.

Cerebral vascular insufficiency due to occlusive lesions regarded as inaccessible is a common problem. The degree of cerebral dysfunction associated with such lesions is dependent in part on the amount of collateral circulation present. By anastomosing the superficial temporal artery to a branch of the middle cerebral artery an increase in collateral circulation is provided to the affected hemisphere. This report describes the results of twenty such procedures. Postoperative angiography demonstrates a 90% patency rate. There is frequent neurological improvement following surgery, and the rate of new TIA's or strokes seems less than would be expected. The most damaging complication of the procedure ist intracerebral haemorrhage. The indications for, and the complications of, such procedures are discussed.

Adult↗
PubMed2001

Cerebral revascularization for cerebral ischemia and stroke prevention in patients with atherosclerotic occlusive disease: defining the population that benefits.

The decision to perform a revascularization procedure on a patient who may or may not benefit from it must be based on an understanding of the impact of spontaneous or therapeutic vascular occlusion on the physiologic, by which the cerebral circulation compensates for vascular occlusions. This impact is patient specific and requires examination of a number of possible physiologic parameters.

Arterial Occlusive Diseases↗
PubMed1979

Acute cerebral revascularization after regional cerebral ischemia in the dog. Part 2: Clinicopathological correlation.

The efficacy of cerebral revascularization by anastomosis of the superficial temporal artery (STA) to the middle cerebral artery (MCA), performed 4 and 24 hours after a regional MCA infarction had been produced by combined occlusion of the MCA and internal carotid artery, was tested in 12 dogs. To control possible intercurrent variables, seven other dogs remained untreated and five had a sham operation. Clinical and pathological changes were recorded and analyzed. An incidence of 85% infarction was obtained in the untreated control group. The severity of the clinical deficits and pathological changes for the anastomosed groups were greater than those seen in the untreated control group. The extent of the infarction was significantly greater (p less than 0.05) in the anastomosed groups than in the sham-operated and control groups. Hemorrhagic infarcts occurred in most of the dogs in the anastomosed groups, but were not present in either control group (p less than 0.05). Two dogs in the 4-hour and one in the 24-hour group improved more than any control dog, but the difference was not statistically significant (p greater than 0.05). In two dogs with occluded anastomosis the clinical deficits and the pathological changes were less than those seen in animals with patent anastomosis. The severity of the pathological and clinical changes correlated well with the reestablishment of flow in the MCA territory. It is proposed that cerebral revascularization at 4 and 24 hours following a regional MCA infarct in the dog is followed by an exacerbation of the microcirculatory obstruction, cerebral edema, and infarction. From improvement noted in three animals the authors suggest that under special conditions the revascularization could benefit some cases following acute cerebral infarction.

Animals↗
PubMed1981

Acute cerebral revascularization: Part 3. Cerebral blood flow.

The efficacy of cerebral revascularization by a superficial temporal-middle cerebral artery anastomosis done 4 and 24 hours following combined occlusion of the middle cerebral and internal carotid arteries (MCA/ICA) was tested in 15 dogs. An untreated and a sham-operated group of 8 and 5 dogs, respectively, controlled possible intercurrent variables. Regional cerebral blood flow (rCBF) was measured by the hydrogen clearance method. Values of normal and preocclusion blood flow under basal conditions and following inhalation of 5% CO2 were similar to values reported by other researchers. Combined MCA/ICA occlusion produced a significant drop in rCBF in the ipsilateral hemisphere (p less than 0.01). The rCBF returned to normal following revascularization in 4 and 24 hours, and after the sham procedure. The rCBF response to inhalation of 5% CO2 was normal in the revascularized group, but was reversed (p less than 0.01) in the sham group. The reversal of flow in the sham group suggested that loss of cerebral autoregulation and steal of blood flow in the infarcted area occurred.

Animals↗
PubMed1999

Hemodynamic and metabolic changes following cerebral revascularization in patients with cerebral occlusive diseases.

Changes in cerebral hemodynamics and metabolism following cerebral revascularization were evaluated using positron emission tomography (PET). Ten patients who had received nonsurgical treatment for 3-6 months for minor completed stroke underwent superficial temporal artery to middle cerebral artery (STA-MCA) bypass surgery. All patients showed no extensive infarction on MR, and responsible vascular lesions were detected in the anterior circulation. A PET study of cerebral blood flow (CBF), oxygen extraction fraction (OEF), cerebral metabolic rate for oxygen (CMRO2), and cerebral metabolic rate for glucose (CMRGlu) measurements was performed before and 1.5 months after surgery using a steady state technique. Angiographically, anastomotic sites were patent in all patients. Seven patients showed neurological improvement after surgery and the others showed no improvement. The decreases in CBF, CMRO2 and CMRGlu recovered to some extent not only on the lesion side but also on the contralateral side after surgery. The increase in OEF values on the lesion side subsequently decreased after surgery. CMRO2 and CMRGlu showed parallel changes. It is concluded that the metabolic improvement afforded by the cerebral revascularization resulted in the neurological improvement, and that PET study is a powerful method for evaluating patients with cerebral occlusive diseases.

Aged↗
PubMed1979

Acute cerebral revascularization: part I. Cerebral ischemia experimental animal model.

Thirty-two mongrel dogs divided into two groups were subjected to a transorbital occlusion of the middle cerebral artery (MCA) or a combined transorbital MCA and cervical internal carotid artery (ICA) occlusion. Clinically apparent deficits were present in the MCA group in 18% of cases and in 73% of MCA/ICA cases. Pathologically, 55% of MCA cases and 73% of MCA/ICA cases had demonstrable areas of infarction. The incidence and severity of clinical deficits as well as the location and extent of pathological infarction were significantly greater (p less than 0.05) with the MCA/ICA group than in the MCA group. The mortality rate and frequency of pathologically apparent infarcts were not statistically different p greater than 0.05. No hemorrhagic infarctions were seen in any case.

Animals↗
PubMed2005

Assessing success after cerebral revascularization for ischemia.

Cerebral revascularization continues to evolve as an option in the setting of ischemia. The potential to favorably influence stroke risk and the natural history of cerebrovascular occlusive disease is being evaluated by the ongoing Carotid Occlusion Surgery Study and the Japanese Extracranial-Intracranial Bypass Trial. For those patients who undergo bypass in the setting of ischemia, four key areas of follow-up include functional neurological status, neurocognitive status, bypass patency, and status of cerebral blood flow and perfusion. Several stroke scales that can be used to assess functional status include the National Institutes of Health Stroke Scale, Bathel Index, Modified Rankin Scale, and Stroke Specific Quality of Life. Neurocognition can be checked using the Repeatable Battery for the Assessment of Neuropsychological Status, among other tests. Bypass patency is checked intraoperatively using various flow probes and postoperatively using magnetic resonance angiography (MRA) or computed tomographic angiography (CTA). Cerebral blood flow and perfusion can be assessed using a host of modalities that include positron emission tomography (PET), xenon CT, single photon emission computed tomography (SPECT), transcranial Doppler (TCD), CT, and MR. Paired blood flow studies after a cerebral vasodilatory stimulus using one of these modalities can determine the state of autoregulatory vasodilation (Stage 1 hemodynamic compromise). However, only PET with oxygen extraction fraction measurements can reliably assess for Stage 2 compromise (misery perfusion). This article discusses the various clinical, neuropsychological, and radiographic techniques available to assess a patient's clinical state and cerebral blood flow before and after cerebral revascularization.

Journal Article↗
PubMed1978

Planned extra-anatomic cerebral revascularization for carotid artery ligation.

Cerebral revascularization, using extra-anatomic bypass grafts of autologous saphenous vein, was performed in three patients to prevent or to compensate for ischemic effects of emergency ligation of a carotid artery. These ligations were required after spontaneous disruption of common carotid arteries in patients with previous irradiation and radical head and neck surgery. External-carotid-to-external-carotid cross-over (submandibular) bypass graft was performed once, and ipsilateral axillointernal carotid bypass grafts twice. The role of infection in carotid artery rupture, the unpredictable nature and different mechanisms of cerebral malfunctions after carotid ligation, technical details of extra-anatomic bypass grafts, and anatomic considerations in the prevention of recurrent infection and bleeding are discussed. A planned approach of cerebral revascularization at the time of ligation appears to be preferable to a fortuitous outcome. Neurological disability and death from cerebral ischemia can be prevented by using extraanatomic bypass vein grafts.

Brain↗
PubMed1985

Acute cerebral revascularization.

Fifteen patients evaluated for acute cerebral ischemia underwent acute cerebral revascularization between March, 1979, and May, 1983. Clinical presentation included crescendo transient ischemic attacks (TIA's) in eight cases, progressing neurological dysfunction in three cases, and completed nonfluctuating deficits in four cases. Nine patients received intravenous heparin but did not improve neurologically. The patients with crescendo TIA's were operated on within 4 hours of their last event; those with progressing deficits were operated on while the deficit was developing, and those with established deficits were operated on 4, 6, 9, and 12 hours, respectively, after the event began. The clinical picture for 10 patients had resolved within 10 hours after surgery. One patient with crescendo TIA's, two with progressing deficits, and two with established deficits had postoperative residual deficits, of which three were mild and two severe. One patient, who had a saphenous vein graft to the middle cerebral artery, developed an intracerebral hematoma. In this prospective noncontrolled nonrandomized study, acute cerebral revascularization was performed safely, had limited risks, and offered the potential to help some patients. Further controlled randomized studies are indicated.

Adult↗
PubMed1990

[Intravascular technics of cerebral revascularization].

Two techniques of cerebral revascularization have been developed: angioplasty of the brachiocephalic vessels (204 cases) and local intra-arterial fibrinolysis in the carotid region (26 cases). Angioplasty appears to be the treatment of choice for inflammatory and atherosclerotic stenoses of the main trunks arising from the aortic arch (82 cases). Stenoses of the origin of the vertebral artery are not often ulcerated and may also be treated by angioplasty (42 cases) as long as the stenosis has been recognized as the cause of vertebral insufficiency symptoms. Among the stenoses of the carotid bifurcation, recurrent postsurgical ones are rather easily treated by angioplasty, particularly when they are recognized early by Doppler examination. Postsurgical and inflammatory stenoses do not require cerebral protection during angioplasty. Conversely, cerebral protection is mandatory for treatment of atherosclerotic stenoses because of the risk of embolic detachment of particles in to brain circulation. A new triple coaxial catheter system has been designed which seems so far to be very efficient. Local intra-arterial fibrinolysis in the carotid region is selected on the basis of clinical signs, the delay after onset and results of CT and complete cerebral angiographic workup. A classification into three topographic groups is proposed. The group at highest risk of post-fibrinolysis hemorrhage is the one with occlusion of the lenticulostriate arteries. It would seem hazardous to undertake fibrinolysis in a patient of this group unless it can be started no later than 4 or 5 hours after clinical onset. Rapid transportation of stroke patients is recommended so that CT and complete arteriography may be performed before deciding whether to use fibrinolytics.

Angioplasty, Balloon↗
PubMed1983

Short vein grafts for cerebral revascularization.

Experience with the use of a short saphenous vein bypass graft for cerebral revascularization is reviewed. Twenty patients with symptomatic atherosclerotic occlusive disease underwent a total of 21 bypass procedures. Cerebral revascularization was performed using a short (5 to 10 cm) saphenous vein graft (SVG) extending from the superficial temporal artery (STA) trunk anterior to the ear in 19 bypasses, or from the occipital artery (OA) immediately behind the mastoid process to the posterior temporal or angular branch of the middle cerebral artery (MCA) in two bypasses. The early patency rate for the SVG bypasses was 90%. Two of the four patients with SVG occlusion were found to have substantial resolution of a severe inaccessible internal carotid artery stenosis that was present preoperatively. Filling of multiple major branches of the MCA through the SVG was seen in 90% of patients on late postoperative conventional angiography. The STA trunk or proximal OA was consistently found to be enlarged on the late studies. None of the patients had recurrence of cerebral transient ischemic attacks. The procedure may be useful as a primary means of cerebral revascularization or as an alternative approach when a scalp artery cannot be used because of its small size, severity of arteriosclerotic changes (a common occurrence), or damage during its dissection. Cerebral blood flow studies suggest that the use of a short SVG has a more favorable effect upon the cerebral circulation than the conventional bypass procedure.

Arteriosclerosis↗
PubMed2001

Cerebral revascularization using radial artery grafts for the treatment of complex intracranial aneurysms: techniques and outcomes for 17 patients.

OBJECTIVE: The goal of this report is to illustrate the use of radial artery grafts as bypass conduits in the management of complex intracranial aneurysms and to describe a new "pressure distension technique" to eliminate postoperative vasospasm, which was a common problem early in our experience. METHODS: This study included a series of 17 patients who were surgically treated between 1994 and January 2001 for complex intracranial aneurysms. Five patients were surgically treated without the pressure distension technique; for 12 patients, the technique was used to reduce postoperative vasospasm. Fourteen of the patients had anterior circulation aneurysms, and three had posterior circulation aneurysms. Five of the patients had undergone previous attempts at direct clipping or excision and reconstruction of the aneurysm in question, and embolization had been performed for one patient with a carotid-cavernous fistula. Thirteen patients underwent permanent revascularization combined with proximal occlusion, trapping, or clipping, and four patients underwent temporary revascularization for cerebral protection during anticipated prolonged occlusion of the parent vessel during aneurysm dissection. Surgical techniques are described, with particular reference to vessel collection and bypass techniques. RESULTS: The outcomes for this group of patients, considering the complexity of the aneurysms and their "inoperability," with respect to direct clipping, were satisfactory. The aneurysms were completely obliterated for all patients, and the grafts were patent for all except one patient on postoperative angiograms. There were two deaths, one attributable to systemic sepsis and the other attributable to cardiac arrest during a transbronchial biopsy. The postoperative Glasgow Outcome Scale scores were either better or the same for all other patients, compared with their preoperative scores. Three of the five patients treated before the institution of the pressure distension technique experienced vasospasm of the graft, with two of those patients requiring angioplasty. For one of those patients, angioplasty led to rupture of the graft. Vasospasm was not observed for any of the 12 patients for whom the pressure distension technique was used. We observed no morbidity related to radial artery collection. CONCLUSION: Revascularization techniques are occasionally necessary for the surgical treatment of complicated intracranial aneurysms. The merits of the use of the radial artery as a bypass conduit are discussed. Radial artery grafts should be considered as alternatives to saphenous vein and superficial temporal artery grafts. The problem of vasospasm of the artery has been solved with the pressure distention technique.

Adult↗
PubMed2002

Cerebral revascularization for aneurysms and tumors.

OBJECTIVE: To discuss the indications, techniques, pitfalls, complication avoidance, and management of cerebral revascularization techniques for the treatment of aneurysms and cranial base tumors. METHODS: The indications for cerebral revascularization procedures included microsurgical occlusion of a parent vessel during the treatment of aneurysms and occlusion of a major vessel during the treatment of basal tumors. The techniques discussed include arterial patch grafting, end-to-end anastomosis, side-to-side anastomosis, arterial interposition grafting, and extracranial-to-intracranial bypass grafting, using radial artery grafts or saphenous vein grafts. RESULTS: During the 15-year period between 1985 and 2000, the senior author performed 24 radial artery grafts, 105 saphenous vein grafts, and 8 other revascularization procedures, among 50 patients with aneurysms and 83 patients with cranial base tumors. The overall patency rate was 95.6%. Twenty-three patients experienced a cerebral infarction; among those patients, 17 (12.5%) exhibited symptoms but the majority demonstrated considerable recovery during the follow-up period. One hundred one patients recovered to an excellent (Glasgow Outcome Scale score of 5) or good (Glasgow Outcome Scale score of 4) condition. Fifteen patients died as a result of recurrence or progression of tumors during the follow-up period. There were five perioperative deaths. For the last 35 patients, the surgical mortality rate was 0%, with all patients returning to an excellent or good condition. CONCLUSION: Although highly specialized, these sophisticated cerebral revascularization techniques should be learned and practiced by all neurosurgeons who wish to microsurgically treat intracranial aneurysms or cranial base tumors.

Anastomosis, Surgical↗
PubMed2001

The role of cerebral revascularization in patients with intracranial aneurysms.

Cerebral revascularization offers an important adjunct to parent-vessel ligation in the treatment of large and otherwise inaccessible intracranial aneurysms. Good or excellent outcomes can be expected in approximately 80% of patients. Poor outcomes and ischemic complications were highest in posterior circulation lesions. Cranial neuropathies from mass effect associated with giant aneurysms of the cavernous and intradural internal carotid artery will improve and be cured in the majority of patients treated with universal revascularization approach. In combination with open parent vessel ligation or endovascular occlusion, durable protection from subarachnoid hemorrhage can be achieved.

Adolescent↗
PubMed1985

Preoperative estimation of cerebral blood flow autoregulation curve for control of cerebral circulation after cerebral revascularization.

In this report, the anesthetic management for cerebral revascularization in 3 patients with ischemic cerebral vascular disease was presented. Arterial pressure was maintained above their ordinary level before revascularization. To prevent cerebral hemorrhage or edema due to the breakthrough phenomenon, the arterial pressure was reduced to the lower limit pressure of cerebral blood flow (CBF) autoregulation which was measured preoperatively. The patients did not show any new neurological deficit after the operations.

Adult↗
PubMed2005

Microsurgical anatomy of cerebral revascularization. Part I: anterior circulation.

OBJECT: Revascularization is an important component of treatment for complex aneurysms that require parent vessel occlusion, skull base tumors that involve major vessels, and certain ischemic diseases. In this study, the authors examined the microsurgical anatomy of cerebral revascularization in the anterior circulation by demonstrating various procedures for bypass surgery. METHODS: Twenty-five adult cadaveric specimens were studied, using 3 to 40 magnification, after the arteries and veins had been perfused with colored silicone. The microsurgical anatomy of cerebral revascularization in the anterior circulation was examined with the focus on the donor, recipient, and graft vessels. The techniques discussed in this paper include the superficial temporal artery (STA)-middle cerebral artery (MCA), middle meningeal artery (MMA)-MCA, and side-to-side anastomoses; short arterial and venous interposition grafting; and external carotid artery/internal carotid artery (ICA)-M2 and ICA-ICA bypasses. Bypass procedures for cerebral revascularization are divided into two categories depending on their flow volume: low-flow and high-flow bypasses. A low-flow bypass, such as the STA-MCA anastomosis, is used to cover a relatively small area, whereas a high-flow bypass, such as the ICA-ICA anastomosis, is used for larger areas. Cerebral revascularization techniques are also divided into two types depending on the graft materials: pedicled arterial grafts, such as STA and occipital artery grafts, and free venous or arterial grafts, which are usually saphenous vein and radial artery grafts. Pedicled arterial grafts are mainly used for low-flow bypasses, whereas venous or arterial grafts are used for high-flow bypasses. CONCLUSIONS: It is important to understand the methods of bypass procedures and to consider indications in which cerebral revascularization is needed.

Anastomosis, Surgical↗
PubMed1982

Preoperative neurobehavioral impairment in cerebral revascularization candidates.

We examined level of performance in 40 candidates for cerebral revascularization and found substantial variability on general indices of neuropsychological performance. Patients differed by duration of their longest ischemic attack, by surgery type, but not by time since onset of their first ischemic attack. Duration of the longest ischemic attack correlated highly with neuropsychological summary scores. In contrast, symptom duration was unrelated to level of performance in 18 additional patients with histories consistent with cerebrovascular ischemia who did not undergo surgery subsequently. We concluded that initial status on neuropsychological tests is an important variable to consider in postoperative followup of patients undergoing cerebral revascularization. More detailed clinical history and finer grained analysis of neuropsychological data promised to reveal additional relationships among clinical symptoms, neurobehavioral data, and underlying neuropathology.

Brain Ischemia↗