“Reverse” superficial temporal artery-middle cerebral artery bypass

A new technical variant on the superficial temporal artery-middle cerebral artery anastomosis was performed in a patient with occlusions of both the left internal and external carotid arteries and persistent ischemic symptomatology. Instead of anastomosing the proximal segment of the superficial temporal artery to the middle cerebral artery as is conventionally done, the distal segment of the superficial temporal artery was anastomosed to a cortical branch of the left middle cerebral artery. Reconstituted flow of the left superficial temporal artery via right superficial temporal artey collateral branches proved adequate to relieve the patient's ischemic episodes. “Reverse” superficial temporal artery-middle cerebral artery anastomosis should be considered in those cases where occlusive disease of the external carotid circulation renders conventional bypass procedures ineffective in the treatment of ischemic symptomatology.     

A study of collateral circulation in acute stage of occlusion of the middle cerebral artery]

Collateral circulation of angiogram in occlusion of main trunk of the middle cerebral artery in acute stage was studied in detail, and compared with the extent of the low density area on CT. Territory of the middle cerebral artery in the lateral view of angiogram was divided into three regions. Collateral circulation time was measured with the period from the maximum filling of carotid siphon to the retrograde maximum filling of collateral circulation. With these studies, the following conclusions were obtained. 1) The degree of collateral circulation is classified into three types. One type with good collateral circulation is type I. Another type with moderate collateral circulation is type II. A further type with poor collateral circulation is type III. Angiographic circulation time in each branch of the middle cerebral artery is measured in each type. 2) There is a tendency that types with the better development of collateral circulation have the smaller low density area on CT. In type I, the smallest low density area on CT appears in the territory of basal ganglia or around corona radiata. In type II or III, the medium or large low density area on CT appears in cortical and/or subcortical territory of the middle cerebral artery. 3) There is a tendency that types with the worse development of collateral circulation have the later collateral circulation time in each region. If collateral circulation time is later than 4 seconds, it is impossible to avoid the appearance of the low density area on CT in C region. In the same way, in B region, it is later than 5 or 6 seconds, in A region, it is later than 7 seconds. But, in type II or III, there are a few cases in which it is impossible to avoid the appearance of the low density area on CT, even if collateral circulation time is earlier than those mentioned. As mentioned above, classifying of collateral circulation is possible to expect the extent of the low density area on CT, and measurement of collateral circulation time is able to estimate the appearance of the low density area on CT. In type I and II, superficial temporal artery to middle cerebral artery anastomosis is apt to make the low density area narrow on CT, and to prevent the appearance of hemorrhagic infarction.     

The Moyamoya syndrome and the neurosurgeon.

Three cases (two children, one adult) presenting the angiographic features of the Moyamoya syndrome are reported, and the variety of the arterial collateral system is described. If there is a progressive neurological deterioration as a consequence of an inadequate collateral circulation, the creation of a new collateral vascular channel by way of anastomosis between the superficial temporal artery and a branch of the middle cerebral artery is proposed.     

Superficial temporal artery to middle cerebral artery anastomosis. Intraoperative evaluation by fluorescein angiography and xenon-133 clearance.

Fluorescein angiography and xenon-133 (133Xe) clearance studies were performed during surgery on 15 patients who were undergoing superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis. Fourteen patients had occlusive disease of the internal carotid artery (ICA), and one patient had severe stenosis of the MCA. Before anastomosis, fluorescein angiography showed slow filling of the MCA branches through collateral channels. Focal areas of impaired microcirculatory filling and washout were seen in the territory of severely sclerotic cortical arteries. The findings of preanastomotic 133Xe clearance studies were variable and a uniform pattern of regional cerebral blood flow (rCBF) changes was not defined. In 55% of the patients, rCBF was reduced to 25 ml/100 gm/min or less at one or more detector sites. Fluorescein angiography provided an immediate assessment of anastomotic patency and clearly displayed the distribution of blood entering the epicerebral circulation through the STA. In 67% of patients, multiple MCA cortical branches filled with fluorescein, whereas in 33% filling was restricted to the receptor artery territory. An immediate, substantial (greater than or equal to 15 ml/100 gm/min) increase in rCBF was demonstrated in 73% of patients after anastomosis. The rCBF changes were consistently better in patients with donor and receptor arteries greater than 1 mm in diameter. Redistribution of collateral input acted to increase rCBF in areas distant from the anastomotic site. Some improvement in fluorescein circulation and rCBF also was seen in cortex supplied by sclerotic MCA branches.     

Double-insurance bypass for internal carotid artery aneurysm surgery

OBJECTIVE: The aim of this article is to present the usefulness of a double-bypass method in the surgical treatment of complex internal carotid artery (ICA) aneurysms. For patients with clippable but complex aneurysms of the ICA having poor collateral circulation, bypass surgery is needed before temporary occlusion of the ICA. We propose a double bypass for safety. METHODS: The superficial temporal artery was anastomosed to the distal cortical branch of the middle cerebral artery (MCA), followed by anastomosis between the radial artery and the inferior trunk of the MCA. For patients with clippable ICA aneurysms, the radial artery was temporarily anastomosed to the inferior trunk of the MCA by raising the ipsilateral forearm to the head after the radial artery was harvested. After the aneurysm had been clipped, the anastomosed radial artery was cut close to the anastomosed site and repositioned back to the original arm. RESULTS: This double-bypass procedure was performed in two patients, and no ischemic complications related to revascularization were observed. Temporary occlusion times of the MCA for superficial temporal artery-to-MCA anastomosis and radial artery-to-MCA anastomosis were 30 and 46 minutes in one patient and 28 and 55 minutes in another. CONCLUSION: This surgical procedure, which we called "double-insurance bypass," can reduce the risk of ischemic complications associated with revascularization of the ICA.     

The usefulnessof STA-MCA anastomosis in trapping vascular disorder (author's transl)

Huge aneurysm taking place within the cavernous sinus or at the junction of the internal carotid artery with the ophthalmic artery must be treated by intra- and extracranial ligation of the internal carotid artery because of its anatomical specificity, if it is to be radically treated. Carotid-cavernous fistula which cannot be cured by embolization must also be treated by ligation of the internal carotid artery. However, if there is only a poor collateral circulation over the area distal to ligated portion, the operation surely incurs severe neurological deficit, so that trapping must be abandoned in such cases. Nevertheless, by establishing a bypass through anastomosis between the superficial temporal artery and the middle cerebral artery, the operation can be done safely. Further, even in cases of aneurysm taking place on the cerebral main vessel in which the aneurysm must be extirpated despite the presence of an important branch shooting-off from the aneurysm, or in some other cases (sphenoidal ridge meningioma, for instance) in which total extirpation of the tumor must necessarily be associated with sacrifice of the main vessel because it is involved in the brain tumor, we think that the operation can be performed rather safely through anastomosis with the vessel to be sacrificed. Some representative examples of such cases are described, and the usefulness of anastomosis between the superficial temporal artery and the middle cerebral artery in trapping of vascular disorders.     

Moyamoya disease: pathophysiology and anesthetic management

Moyamoya disease, an ischemic cerebrovascular disease, is characterized by a slowly increasing bilateral occlusion of the internal carotid circulation. Although collateral pathways are formed, therapy is aimed at further increasing blood flow by surgical anastomosis before ischemic events and fixed neurologic defects occur. This disease remains one of the few indications for performance of the operation of superficial temporal artery to middle cerebral artery anastomosis. Anesthetic considerations involve increasing substrate supply and decreasing demand for its use. Two cases of moyamoya disease are described, noteworthy not only because of the rarity of the disease but because of its occurrence in the Hispanic race rather than the traditional appearance in those only of Japanese descent. The anesthetic management is outlined and the literature reviewed.     

Pre- and intraoperative methods of controlling cerebral circulation in giant aneurysm surgery

The surgical treatment of giant aneurysms usually requires temporary clipping of the aneurysmatic vessel. In planning the surgical approach and in applying temporary clips, the surgeon must consider collateral circulations. The functional integrity of the collateral vessels frequently decides the patient's outcome.In 8 patients with internal carotid artery giant aneurysm, measurements of blood flow velocities in the ipsilateral middle cerebral artery were performed preoperatively with transcranial Doppler ultrasound (TCD) during manual occlusion of the carotid artery at the neck. Three different perfusion patterns were established, and each collateral capacity was rated as insufficient, temporarily sufficient, or long-term unproblematic. Surgical strategies were conceived. In one patient with giant aneurysm of the middle cerebral artery the temporary occlusion test was not carried out preoperatively.Intraoperatively, collateral circulation was controlled using microvascular Doppler sonography (MVD). In 8 cases cortical blood flow (CoBF) was monitored by thermal diffusion flow probe and/or laser Doppler. In some cases, the complex pathological anatomy required a change in surgical strategy and a new MVD determination of collateral capacity. Despite these precautions 2 patients suffered ischemia of the basal ganglia and the white matter.     

Trauma to the high cervical carotid artery

An alternative approach to the treatment of distal extracranial nonoccluding internal carotid artery penetrating injuries is described in which internal carotid artery ligation is followed expectantly. A warning transient neurologic deficit prompted an unsuccessful attempt at revascularization via a superficial temporal artery to middle cerebral artery anastomosis. The failure of the anastomosis was thought to be secondary to a postinjury hypercoagulable state and a diminished demand for intracranial blood flow secondary to an unexpected, impressive development of collateral blood supply.     

Giant pediatric aneurysm treated with ligation of the middle cerebral artery with the Drake tourniquet and extracranial-intracranial bypass

Saccular intracranial aneurysms occur infrequently in children, and the incidence of pediatric giant aneurysms is statistically in the same proportion as in adults. The management of these giant aneurysms can be treacherous. This paper presents a case of a 9-year-old boy with a giant aneurysm of the right middle cerebral artery that was successfully managed by ligation of the middle cerebral artery using a Drake tourniquet with the patient awake and by augmentation of the middle cerebral artery circulation with superficial temporal artery-middle cerebral artery anastomosis without excision of the lesion.     

Patch angioplasty to repair the arteriotomy defect in the wall of the middle cerebral artery after failure of superficial temporal artery-middle cerebral artery anastomosis in moyamoya disease--case report

A 65-year-old woman presented with moyamoya disease associated with a saccular aneurysm of the posterior cerebral artery. The surgical plan required superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis to be conducted before neck clipping of the aneurysm to provide collateral flow via the STA to prevent ischemia if temporary occlusion of the parent artery of the aneurysm was needed. However, the anastomotic procedure failed because the STA was occluded at the site of temporary clip application. End-to-end anastomosis of the STA was planned after excising the occluded site of the STA, but end-to-end anastomosis could not be performed because the donor artery was too short for anastomosis to the branch of the MCA. Therefore, patch grafting using a piece of wall of the STA was performed to repair the arteriotomy defect in the wall of the MCA, followed by neck clipping of the saccular aneurysm in the posterior circulation via the subtemporal approach. Vascular reconstruction can be recommended if arterial anastomosis between a superficial skin artery and a branch of the MCA is impossible due to an intraoperative accident or technical difficulty and reperfusion is necessary.     

Assessment of the cortical artery using computed tomography angiography for bypass surgery in moyamoya disease

Computed tomography angiography (CTA) is often used to assess the vascular status in moyamoya disease. The purpose of the study is to identify the characteristics of cortical arteries (M4) of moyamoya disease on CTA; the clinical significance of which is also discussed. A total of 38 hemispheric sides of 27 patients with moyamoya disease were included in this study. The number of M4 was visualized on CTA using cortical surface imaging and compared between the moyamoya disease group and the non-moyamoya disease group or the control group. Then, the clinical and radiological factors associated with the number of M4, the distribution of M4, and collateral circulation were examined. The number of M4 was lower in the moyamoya disease group than in the non-moyamoya disease group and in the control group (p < 0.05). There are few predictive clinical factors of the number of M4 except male sex. The prefrontal artery, precentral artery, central artery, and angular artery had a significantly higher prevalence in moyamoya disease (p < 0.05). The durocortical and periventricular anastomosis had a significantly higher prevalence in moyamoya disease (p < 0.05). The prevalence and distribution pattern of cortical arteries in moyamoya disease differed from that of the non-moyamoya disease group, and the distribution patterns of M4 might be influenced by collateral circulation. It is thus essential to recognize M4 to assess the recipient artery so as to ensure superficial temporal artery–middle cerebral artery bypass.     

Surgical treatment of moyamoya disease in pediatric patients--comparison between the results of indirect and direct revascularization procedures.

Either encephaloduroarteriosynangiosis (EDAS) or superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis combined with encephalomyosynangiosis (EMS) has been performed on most of the children with moyamoya disease in our department. EDAS alone was done in the parietal region of 13 sides in 10 patients, and STA-MCA anastomosis with EMS in the parietal region was done on 7 sides in 6 patients. The surgical results of these two different procedures were then compared. Postoperative collateral formation was observed on external carotid angiograms, and the improvement of clinical symptoms was monitored for 1 year after the bypass procedure. STA-MCA anastomosis with EMS was found to be superior to EDAS in both the development of collateral circulation (P less than 0.05) and postoperative clinical improvement (P less than 0.01). EDAS can be done easily and safely on small children with moyamoya disease, but STA-MCA anastomosis with EMS is considered to be more appropriate, whenever possible.     

Superficial temporal-middle cerebral artery bypass: clinical pre- and postoperative angiographic correlation

Between 1974 and 1982, an anastomosis between a pedicle of the superficial temporal artery (STA) and a cortical branch of the middle cerebral artery (MCA) was performed in 163 carotid systems in 157 patients for internal carotid artery occlusion in whom postoperative angiograms were available for analysis. The angiographic opacification of the arterial system was correlated with the patient's preoperative neurological function and stroke in the follow-up period. From this analysis, the following observations were made: 1) 96% of bypasses were patent; 2) 80% of bypasses achieved a high or medium MCA filling score; 3) there was hypertrophy of the STA in 70% of the cases; 4) greater bypass filling occurred in hemispheres with nonvisualized preoperative collateral circulation than in those with readily visualized collateral flow; 5) a meaningful correlation between angiographically assessed postoperative bypass function and stroke rate was not possible because only four patients suffered an ipsilateral hemispheric stroke in the 8-year follow-up period; and 6) patients who were neurologically unstable before the procedure were at greatest risk for a stroke in the follow-up period. It is apparent that objective analysis of the effectiveness of an STA-MCA bypass, or any other form of extracranial bypass, must await the development of new diagnostic studies in which high-resolution three-dimensional quantification of cerebral blood flow is possible. These studies will necessarily be correlated with preoperative and follow-up clinical data.     

Venous Reddening as a Possible Sign of Hyperperfusion after Superficial Temporal Artery-Middle Cerebral Artery Anastomosis for Moyamoya Disease: Case Report

Here we report a case of moyamoya disease in which cortical veins reddened after superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis, following postoperative hyperperfusion. A 37-year-old man with moyamoya disease suffered cerebral infarction in his right hemisphere. Single photon emission computed tomography (SPECT) showed impaired cerebral blood flow (CBF) in both cerebral hemispheres. The patient underwent STA-MCA anastomosis in the right cerebral hemisphere. During operation, soon after declamping the STA, cortical veins near the anastomosis site changed its color from blue to red. This change was repeatable by clamping and declamping of the STA. Postoperative SPECT and computed tomography (CT) demonstrated increased CBF and subarachnoid hemorrhage at the anastomosis site, suggesting the occurrence of postoperative hyperperfusion. By strictly controlling the patient''s blood pressure, the syndrome resolved 1 week after the operation. We propose that the venous reddening after STA-MCA anastomosis may be a sign of postoperative hyperperfusion.     

Pseudoaneurysm complicating superficial temporal artery-superior cerebellar artery bypass

A 60-year-old man with vertebrobasilar ischemia unrelieved by anticoagulation was found to have a midbasilar stenosis with an inadequate basilar collateral circulation. He underwent a right superficial temporal-superior cerebellar artery bypass. Following this operation he had a subarachnoid hemorrhage and right third nerve palsy that was due to formation of a pseudoaneurysm at the site of the anastomosis. This aneurysm was managed by ligation of the right superficial temporal artery. Subsequently it became necessary to perform a left superficial temporal artery-superior cerebellar artery bypass because of severe posterior circulation ischemic symptoms.     

Superficial Temporal Artery to Middle Cerebral Artery Bypass

The superficial temporal artery to middle artery bypass is a technique that allows the blood supply from the extracranial carotid circulation to be routed to the distal middle cerebral artery branches. The procedure allows blood flow to bypass proximal lesions of the intracranial vasculature. The performance of this bypass requires specialized microvascular training and the use of microvascular techniques. The techniques involved in performing these procedures include microdissection of the superficial temporal artery in the scalp, microdissection of the recipient middle cerebral artery branches near the sylvian fissure, and anastomosis techniques using either microvascular sutures or a microanastomotic device. The successful completion of the bypass and subsequent patency requires meticulous attention to technical details.     

Hemodynamic effects of STA-MCA anastomosis on patients with occlusion of the main cerebral artery

PURPOSE: We studied cerebral circulation in patients with occlusion of the main cerebral artery and investigated the efficacy of STA-MCA anastomosis. PATIENTS AND METHODS: Thirty-six patients with occlusion of the main cerebral artery were studied. Twenty-three patients had occlusion of the internal carotid artery and 13 had occlusion of the middle cerebral artery. The mean age was 62 years. Cerebral blood flow (CBF) was measured in all patients and cerebrovascular reactivity (CVR) was examined in 11 patients by xenon enhanced CT. Intraoperatively, cortical arterial pressure and anastomotic flow were measured. RESULTS: There was no perioperative mortality or morbidity. There was no ipsilateral stroke recurrence during the follow-up period averaging 35.1 months. Patency of the anastomosis was verified in 91% of the patients by magnetic resonance angiography. Twenty-three (64%) patients showed decreased CBF before the operation and 57% of these patients showed improvement to the normal range after STA-MCA anastomosis. All of the eight patients with decreased CVR showed improvement after the operation. Anastomotic flow correlated significantly with the cortical arterial pressure. CONCLUSION: STA-MCA anastomosis could improve cerebral circulation of patients with low CBF or low CVR due to occlusion of the main cerebral arterial. It was concluded that STA-MCA anastomosis may contribute to the reduction of stroke recurrence, if perioperative complications are reduced.     

Carotid occlusive disease presenting with loss of consciousness

The authors report 9 patients who presented with loss of consciousness (syncope) due to occlusive carotid artery diseases. All patients were males, and their age ranged from 59 to 83 years. The attack was associated with dehydration or hypotension in 5 patients. MRI demonstrated fresh cerebral infarction in the watershed zone. Cerebral angiography revealed occlusion of the unilateral internal carotid artery (ICA) in 7 patients, severe stenosis of the bilateral ICA in one, and occlusion of the unilateral ICA and severe stenosis of the contralateral ICA in one. Single photon emission tomography (SPECT) or positron emission tomography (PET) suggested reduced cerebral perfusion reserve because of inappropriate development of collateral circulation in 4 out of 9 patients. These 4 patients underwent superficial temporal artery to middle cerebral artery anastomosis and/or carotid endarterectomy. Other 5 patients were medically treated. No further episode of syncope occurred in all 9 patients during follow-up periods. The results suggest that occlusive carotid artery diseases should be taken in considerations as a cause of syncope attack.     

Superficial temporal-middle cerebral artery anastomosis in Moyamoya disease

Summary A 41-year-old Libyan woman with Moyamoya disease and persisting post-stroke neurological deficits was treated by a superficial temporal-middle cerebral artery (STA-MCA) anastomosis. The postoperative angiograms revealed that the STA was rapidly irrigating the territory of the middle cerebral artery including those regions that had been filled preoperatively via different networks of collaterals. Furthermore prompt venous drainage was seen to occur postoperatively. Following surgery EEG analyses revealed considerable increase in the electrical brain activity, and neurological examinations showed reversal of neurological deficits. The dependence of the postoperative neurological improvement on the increased cerebral blood supply through the new collateral channel could be demonstrated by the effect of temporary occlusion of the STA on the electrical brain activity.