Is Precise Targeting of the Recipient Artery in a Superficial Temporal Artery-Middle Cerebral Artery Anastomosis Crucial?

OBJECTIVE: To investigate the difference in treatment outcomes according to the method used to select the recipient artery in superficial temporal artery-middle cerebral artery (STA-MCA) anastomoses. METHODS: We retrospectively analyzed the cases of 35 patients who underwent an STA-MCA anastomosis for internal carotid artery/MCA occlusion or stenosis. Patients were divided into two groups based on whether the recipient artery was precisely targeted by single-photon emission computed tomography (SPECT group) or less precisely targeted by visual assessment (Visual group). Then the bypass results in both groups were evaluated postoperatively based on changes in the regional cerebral blood flow (rCBF) and clinical outcomes. RESULTS: The delineated recipient artery in magnetic resonance angiography (MRA) matched the intraoperatively selected artery in 87.6% of the SPECT group cases and 83.3% of the Visual group cases. The SPECT group's digital subtraction angiography (DSA) findings coincided with the intraoperative selection in 76.9% of cases, and the MRA findings corresponded with the DSA findings in 92.3%. The postoperative areas with increased rCBF matched the perfused areas of intraoperatively selected arteries in 80.0% of the SPECT group cases and 77.8% of the Visual group cases. Postoperatively increased rCBF areas matching totally or partially with preoperative low-perfusion areas were observed in all cases. CONCLUSIONS: The present results revealed no significant differences in the change in rCBF in the low-perfusion area between the patients whose recipient arteries were selected by SPECT or visual assessment.

Association of Superficial Temporal Artery Dilatation with Headache After Revascularization in Adult Moyamoya Disease.

BACKGROUND: The underlying mechanisms of headache in adult moyamoya disease (MMD) are not clear. The aim of this study is to clarify the factors that are associated with headache in adult patients with MMD after superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis. METHODS: We retrospectively analyzed the cases of 68 adult patients with MMD: 30 with surgery and 38 without surgery. Each STA-MCA anastomosis was performed by the standard technique. Magnetic resonance angiography (MRA) and single photon emission computed tomography were performed perioperatively. We stratified the intensity and frequency of the patients' headaches into 4 ranks. Pre- and postoperative STA diameters were retrospectively measured on digital subtraction angiography (DSA) and/or MRA. RESULTS: In the surgery group, preoperative regional cerebral blood flow (rCBF) laterality and a postoperative rCBF increase >20% showed no significant difference between the patients with and without headache with a univariate analysis. The postoperative STA diameters of the distal branch (DSA) and main trunk (DSA/MRA) in the patients with headache were significantly larger than those of the patients without headache. The rate of postoperative increase of the STA diameters of the distal branch/main trunk was also significantly higher in the patients with headache than those without headache. A multivariate analysis showed that the standard regression coefficient ß for sex, a >20% increase of postoperative rCBF, and the increase rate of the STA diameter of the distal branch shown by DSA was 0.37, 0.54, and 0.56, respectively. CONCLUSIONS: The results of our analyses revealed that aside from ischemia, the postoperative increase rate of the STA may be a candidate reason for headache, especially in adult patients with MMD.

Revaluation of collateral pathways as escape routes from hyperemia/hyperperfusion following surgical treatment for carotid stenosis.

BACKGROUND: Although acetazolamide-challenged single-photon emission CT (SPECT) is recommended before carotid endarterectomy (CEA) and carotid artery stenting (CAS), given the relationship between preoperative decreased cerebrovascular reserve (CVR) and postoperative cerebral hyperperfusion syndrome (CHS), it is controversial whether all cases should be checked. METHODS: I-IMP-SPECT at rest was performed for 65 operative cases of carotid stenoses. At preoperative MR angiography we classified cases into two groups: G, featuring an anterior communicating artery with bilateral A1 with/without posterior communicating arteries; and P, a poor-escape-route group which did not match these criteria. Postoperative rCBF patterns were divided into two types: B, bilateral rCBF increase; and I, ipsilateral rCBF increase. RESULTS: Cases with high postoperative increase rate of rCBF were most frequently found in Group P and the Type I cases (p < 0.001). All four cases with hyperemia or hyperperfusion belonged to Group P. Only two out of 48 patients in Group G were Type I, both demonstrating a preoperative rCBF decrease rate more than 10 % as compared to the contralateral side. CONCLUSIONS: From the present study, preliminary analysis of escape routes by preoperative MR angiography before surgical treatment of carotid stenosis is recommended and CVR investigation with acetazolamide-challenge SPECT should be considered for those relatively few cases with poor escape routes.