Superficial Temporal Artery-middle Cerebral Artery Anastomosis Research Articles

60歳以上の高齢もやもや病患者に対する血行再建術

Superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis prevents cerebral ischemic attack by improving cerebral blood flow in patients with moyamoya disease (MMD). STA-MCA anastomosis is generally recommended for adult MMD patients with ischemic symptom, but its efficacy for elderly patients is unclear. Among 144 consecutive cases with MMD undergoing STA-MCA anastomosis with pial synangiosis in 197 hemispheres, nine patients (10 hemispheres) were over 60 years old (mean 63.5 years old). The incidence of surgical complications including infarction and cerebral hyperperfusion (CHP) was compared to those of the patients under 60 years old. In nine elderly patients undergoing revascularization surgery for 10 hemispheres, the incidence of symptomatic CHP was as high as 30% (3/10), and two of the three patients developed intracranial hemorrhage in the acute stage. One patient developed cerebral infarction at the remote area during the blood pressure lowering against CHP (10%, 1/10). The incidence of symptomatic hemorrhage due to CHP was significantly higher in elderly patients (20%, 2/10) compared to younger patients (1.6%, 3/187) (p＝0.0101). Regarding final outcome of elderly patients, seven patients showed improvement of modified Rankin Scale, and two temporarily deteriorated but recovered to the preoperative status three months after surgery. Elderly patients with MMD may potentially have a higher risk of intracranial hemorrhage due to CHP compared to younger patients. Surgical indication should be carefully decided for elderly MMD patients, and intensive peri-operative management is essential to avoid surgical complications including CHP and ischemia.

Preliminary study of neurocognitive dysfunction in adult moyamoya disease and improvement after superficial temporal artery-middle cerebral artery bypass.

ObjectiveMoyamoya disease (MMD) is a chronic cerebrovascular occlusive disease of unknown etiology. In addition, the neurocognitive impairment of adults with MMD is infrequently reported and, to date, has not been well described. We attempted to determine both the neurocognitive profile of adult moyamoya disease and whether a superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis can improve the neurocognitive impairment in exhibiting hemodynamic disturbance without stroke.MethodsFrom September 2010 through November 2012, 12 patients with angiographically diagnosed MMD underwent STA-MCA anastomosis for hemodynamic impairment. Patients with hypoperfusion and impaired cerebrovascular reserve (CVR) capacity but without evidence of ischemic stroke underwent a cognitive function test, the Seoul Neuropsychological Screening Battery (SNSB). Five patients agreed to undergo a follow-up SNSB test. Data from preoperative and postoperative neurocognitive function tests were compared and analyzed.ResultsFive of 12 patients were enrolled. The median age was 45 years (range, 24-55 years). A comparison of preoperative to postoperative status of SNSB, memory domain, especially delayed recall showed significant improvement. Although most of the domains showed improvement after surgery, the results were not statistically significant.ConclusionIn our preliminary study, large proportions of adult patients with MMD demonstrate disruption of cognitive function. This suggests the possibility of chronic hypoperfusion as a primary cause of the neurocognitive impairment. When preoperative and postoperative status of cognitive function was compared, memory domain showed remarkable improvement. Although further study is needed, neurocognitive impairment may be an indication for earlier intervention with reperfusion procedures that can improve cognitive function.

Minocycline Prevents Focal Neurological Deterioration Due to Cerebral Hyperperfusion After Extracranial-Intracranial Bypass for Moyamoya Disease

Cerebral hyperperfusion (CHP) is a potential complication of superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis for moyamoya disease (MMD), and optimal postoperative management has not yet been established. Minocycline, a neuroprotective antibiotic agent, plays a role in blocking matrix metalloproteinase 9 (MMP-9), which contributes to edema formation and hemorrhagic conversion after cerebral ischemia-reperfusion. Patients with MMD have been shown to have increased serum MMP-9 levels. To examine the effect of minocycline on the prevention of postoperative CHP after STA-MCA anastomosis for MMD. N-isopropyl-p-[I]iodoamphetamine single-photon emission computed tomography was performed 1 and 7 days after STA-MCA anastomosis on 109 hemispheres in 86 consecutive patients with MMD (ages, 9-69 years; mean, 37.2 years). Postoperative systolic blood pressure was strictly maintained at lower than 130 mm Hg in all 109 surgeries. The most 60 recent hemispheres were managed by the intraoperative and postoperative intravenous administration of minocycline hydrochloride (200 mg/d). The incidence of focal neurological deterioration (FND) due to CHP was then compared with that in 36 patients undergoing 49 surgeries managed without minocycline. FND due to CHP was observed in 4 operated hemispheres in patients treated without minocycline (4/49, 8.16%), and in none in the minocycline-treated group (0/60) (P = .0241). Multivariate analysis revealed that minocycline administration (P < .001), surgery on the left hemisphere (P = .031), and a smaller recipient artery diameter (P < .001) significantly correlated with FND due to CHP. The administration of minocycline with strict blood pressure control may represent secure and effective postoperative management to prevent symptomatic CHP after STA-MCA anastomosis for MMD.

Investigating the mechanisms of perioperative ischemic stroke in the Carotid Occlusion Surgery Study

The Carotid Occlusion Surgery Study (COSS) was a large, prospective clinical trial that examined whether superficial temporal artery-middle cerebral artery (STA-MCA) bypass, in addition to best medical therapy, reduced the risk of ipsilateral ischemic stroke in patients with carotid artery occlusion and hemodynamic cerebral ischemia. Despite improved cerebral hemodynamics and excellent bypass graft patency rates, COSS failed to show a benefit for the surgical group with respect to ipsilateral stroke recurrence at 2 years after treatment. This was due to a lower than expected rate of recurrent ipsilateral stroke in the medically treated group and a high rate of perioperative ipsilateral strokes in the surgical group. Critics of the trial have cited surgeon inexperience and technical difficulties related to the performance of the bypass graft as a leading cause of failure of the trial. The authors retrospectively identified all patients from the COSS with an ipsilateral, perioperative (< 30 days) ischemic stroke after STA-MCA cortical branch anastomosis. Study records, operative notes, stroke adjudication forms, and imaging studies were reviewed. Ischemic strokes were characterized as bypass graft related or non-bypass graft related based on clinical and radiographic findings. Fourteen of 93 surgically treated patients experienced an ipsilateral, perioperative ischemic stroke. Postoperatively, the mean oxygen extraction fraction (OEF) ratio between the symptomatic and asymptomatic cerebral hemisphere significantly improved in these patients (1.30 ± 0.18 preoperative vs 1.12 ± 0.11 postoperative; p = 0.02), but did not normalize. In this cohort, total MCA occlusion time during the anastomosis (54.3 ± 23.5 minutes) was no different from the MCA occlusion time in those surgical patients who did not have a perioperative stroke (45.4 ± 24.2 minutes, p = 0.2). Bypass graft patency rates in patients with a perioperative stroke were 92% at 30 days (11 of 12 patients with patency data) and 83% at last follow-up visit (10 of 12 patients with patency data). These patency rates were not significantly different from those achieved at 30 days (100%; 76 of 76 patients with patency data; p = 0.14) and at last follow-up (99%; 71 of 72 patients with patency data; p = 0.052) in patients without a perioperative stroke. Eighty-six percent (12 of 14 patients) of strokes were likely attributable to factors unrelated to the STA-MCA anastomosis. Only 21% of strokes (3 of 14 patients) were in the territory of the recipient vessel and likely related to technical performance of the anastomosis itself. One patient was thought to have dual stroke mechanisms. Only a small minority of ipsilateral, perioperative ischemic strokes in the COSS could be attributed to technical problems of the bypass anastomosis. The majority of ischemic strokes could not be ascribed to this cause and were most likely due to patient hemodynamic fragility and the inability of patients to tolerate surgery.

Predictive factors of symptomatic cerebral hyperperfusion after superficial temporal artery-middle cerebral artery anastomosis in adult patients with moyamoya disease

Symptomatic cerebral hyperperfusion (SCH) is a potential complication after superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis in patients with moyamoya disease. This retrospective study was designed to determine factors associated with SCH after STA-MCA anastomosis in adult moyamoya patients. Eighty-two adult moyamoya patients undergoing STA-MCA anastomosis between July 2005 and December 2010 were enrolled. Laboratory data such as haemoglobin and white blood cell (WBC) count, preoperative (patient characteristic data, initial clinical manifestation, the angiographic staging), intraoperative (surgical time, the operative side, anaesthetic technique, fluid balance, arterial pressure, arterial partial pressure of carbon dioxide, the lowest haematocrit, and intraoperative transfusion), and postoperative (arterial pressure, Acute Physiology and Chronic Health Evaluation II score) data were collected and used as predictable factors for postoperative SCH, in which a focal intense increase in cerebral blood flow at the anastomosis site was shown in postoperative single-photon emission computed tomography. Among 82 patients with 99 surgeries, 39 patients (47 sides, 47%) suffered from transient neurological deterioration due to SCH from 1 to 9 days after operation (median: 2 days), which was sustained for 1-14 days (median: 7 days). The operation on the dominant hemisphere [odds ratio (OR), 5.09; 95% confidence interval (CI), 2.07-12.54, P<0.001] was an independent risk factor for SCH. Also, WBC count on postoperative day 1 was significantly correlated with SCH (OR 1.19; 95%CI, 1.02-1.38, P=0.029). The operation on the dominant hemisphere and increased postoperative WBC count may be associated with SCH after STA-MCA anastomosis in adult-onset moyamoya patients.

Electroencephalographic Evaluation of Cerebral Hyperperfusion Syndrome Following Superficial Temporal Artery-Middle Cerebral Artery Anastomosis

Low-flow bypass, such as superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis, can result in cerebral hyperperfusion syndrome (CHS). The present study evaluated the pathophysiological conditions of CHS through the use of repeated electroencephalography (EEG). Among a total of 22 patients who underwent STA-MCA anastomosis over a course of 4 years, 3 patients were diagnosed with CHS based on clinical symptoms and neuroradiological examinations, including cerebral blood flow evaluation. Case 1 and Case 2 developed CHS on postoperative day 1, when EEG demonstrated focal slow waves on the frontal region of the operated side, indicating cortical dysfunction in these areas. Although prompt recovery of these EEG findings was noted with improvement of the clinical symptoms in Case 1, Case 2 developed an intracranial hemorrhage on postoperative day 5, when EEG clearly depicted persistent nonconvulsive status epilepticus (NCSE) after control of convulsive status epilepticus. In contrast, the clinical onset in Case 3 was delayed to postoperative day 6 and EEG revealed frequent ictal discharges in the operated hemisphere, although convulsive seizures were not apparent. Administration of anticonvulsants was performed after the diagnosis of NCSE, and complete recovery from CHS was achieved. Although the pathophysiology of CHS is cortical dysfunction, ictal hyperperfusion associated with NCSE could be included. The present findings emphasize the importance of repeated EEG examinations in the differential diagnosis of the various types of pathophysiological conditions of CHS.

Surgical results of the Carotid Occlusion Surgery Study.

The Carotid Occlusion Surgery Study (COSS) was conducted to determine if superficial temporal artery-middle cerebral artery (STA-MCA) bypass, when added to the best medical therapy, would reduce subsequent ipsilateral stroke in patients with complete internal carotid artery (ICA) occlusion and an elevated oxygen extraction fraction (OEF) in the cerebral hemisphere distal to the occlusion. A recent publication documented the methodology of the COSS in detail and briefly outlined the major findings of the trial. The surgical results of the COSS are described in detail in this report. The COSS was a prospective, parallel-group, 1:1 randomized, open-label, blinded-adjudication treatment trial. Participants, who had angiographically demonstrated complete occlusion of the ICA causing either a transient ischemic attack or ischemic stroke within 120 days and hemodynamic cerebral ischemia indicated by an increased OEF measured by PET, were randomized to either surgical or medical treatment. One hundred ninety-five patients were randomized: 97 to the surgical group and 98 to the medical group. The surgical patients underwent an STA-MCA cortical branch anastomosis. In the intention-to-treat analysis, the 2-year rates for the primary end point were 21% for the surgical group and 22.7% for the medical group (p = 0.78, log-rank test). Fourteen (15%) of the 93 patients who had undergone an arterial bypass had a primary end point ipsilateral hemispheric stroke in the 30-day postoperative period, 12 within 2 days after surgery. The STA-MCA arterial bypass patency rate was 98% at the 30-day postoperative visit and 96% at the last follow-up examination. The STA-MCA arterial bypass markedly improved, although it did not normalize, the level of elevated OEF in the symptomatic cerebral hemisphere. Five surgically treated and 1 nonsurgically treated patients in the surgical group had a primary end point ipsilateral hemispheric stroke after the 30-day postoperative period. No baseline characteristics or intraoperative variables revealed those who would experience a procedure-related stroke. Despite excellent bypass graft patency and improved cerebral hemodynamics, STA-MCA anastomosis did not provide an overall benefit regarding ipsilateral 2-year stroke recurrence, mainly because of a much better than expected stroke recurrence rate (22.7%) in the medical group, but also because of a significant postoperative stroke rate (15%). Clinical trial registration no.: NCT00029146.

Efficacy of Prophylactic Blood Pressure Lowering according to a Standardized Postoperative Management Protocol to Prevent Symptomatic Cerebral Hyperperfusion after Direct Revascularization Surgery for Moyamoya Disease

Background: Cerebral hyperperfusion is a potential complication of superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis for moyamoya disease, but the optimal postoperative management has not been determined. Aggressive blood pressure lowering is controversial because of the risk of ischemic complications. Objective: To establish the optimal postoperative management protocol to prevent symptomatic cerebral hyperperfusion in moyamoya disease. Methods: N-isopropyl-p-[¹²³I]-iodoamphetamine single-photon emission computed tomography was performed 1 and 7 days after STA-MCA anastomosis on 152 hemispheres from 108 consecutive patients with moyamoya disease (2–69, mean 33.3 years). Between 2004 and 2007 (period 1), 65 patients were maintained under normotensive conditions after 93 operations, and only patients with cerebral hyperperfusion underwent blood pressure lowering. Between 2008 and 2010 (period 2), all 43 patients were prospectively subjected to intensive blood pressure lowering (<130 mm Hg of systolic blood pressure) immediately after 59 operations. Then the incidence of symptomatic cerebral hyperperfusion was compared between the two groups. Results: Systolic blood pressure the day after surgery was significantly lower in period 2 (mean, 120.9 mm Hg) than in period 1 (133.9 mm Hg) (p < 0.0001). Symptomatic cerebral hyperperfusion was seen in 22 patients during period 1 (23 hemispheres, 24.7%), but only in 4 patients during period 2 (6.7%, p = 0.0047). Multivariate analysis revealed that prophylactic blood pressure lowering was significantly associated with the prevention of symptomatic cerebral hyperperfusion (p = 0.015). Symptomatic cerebral hyperperfusion was relieved in all patients without developing a permanent neurological deficit due to cerebral hyperperfusion. Conclusion: Prophylactic blood pressure lowering prevents symptomatic cerebral hyperperfusion after STA-MCA anastomosis in patients with moyamoya disease. Accurate diagnosis of cerebral hyperperfusion and blood pressure lowering, and considering the severity of hemodynamic compromise in the contralateral and/or remote areas are essential for postoperative management of moyamoya disease.

Experience of 97 patients with moyamoya disease: long-term follow-up at a single center

To explore the medium and long-term outcomes of patients with Moyamoya disease (MD) undergoing surgery and conservative treatment at a single institution and analyze the related prognostic factors. A retrospective review was conducted for 97 MD patients at Beijing Tiantan Hospital from January 2000 to December 2007. They were divided into 3 groups according to treatments: superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis (n = 31), indirect vascular revascularization group (n = 38) and conservative treatment group (n = 28). The primary follow-up events included death, recurrent cerebral hemorrhage, new cerebral infarction and transient ischemic attack (TIA). All were available for analysis with the complete follow-up data. The average follow-up period of was 85 ± 38 months. In total, there were 6 deaths with all-cause mortality (6.1%). Among them, 5 (5.1%) patients died from recurrent cerebral hemorrhage. And 17 episodes of rebleeding occurred in 11 patients. Two episodes of intracranial hemorrhage were found in 4 patients. The risk of rebleeding was 17.5%. In the STA-MCA group, 23(74%) cases had excellent recovery, 5 cases fared worse and there was no death case. Among the patients undergoing indirect vascular revascularization, 28 cases recovered favorably, 4 cases progressed and 3 cases died. In the conservative treatment group, 17 patients recovered favorably, 7 progressed, 9 experienced 15 episodes of rebleeding and 3 died. Multivariate Cox regression analysis showed that the method of treatment was an independent prognostic factor for MD and surgical revascularization was superior to conservative treatment. No correlation was found between the patient age, gender, familial history, unilateral or bilateral and prognosis (P > 0.05). Kaplan-Meier stroke risk analysis showed the risk of recurrent hemorrhage in the revascularization surgery group was lower than that in the conservative group. And no difference existed between STA-MCA and indirect arterial anastomoses. Rebleeding is a major cause of poor prognosis, mobility and mortality in MD patients. Surgical revascularization offers better long-term outcomes than conservative treatment. And direct arterial anastomoses may decrease recurrent hemorrhage effectively.

Watertight Dural Closure Constructed With DuraSealTM for Bypass Surgery

Superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis is a common procedure for the treatment of cerebral ischemia and is useful for cerebral aneurysms and tumors. The STA has to pass through the dura and the dura cannot be sutured tightly around the STA to prevent vessel narrowing, so subcutaneous cerebrospinal fluid (CSF) collection is common. This study analyzed the feasibility of using a synthetic dural sealant in the STA-MCA anastomosis to establish watertight closure. Twenty-four patients underwent STA-MCA anastomosis for cerebral ischemia or cerebral aneurysm. After creation of a standard STA-MCA anastomosis, the dura was reapproximated closely, leaving a small defect around the STA. Then, DuraSeal(TM) was sprayed over the dural defect, and a negative-pressure drain was positioned before closing the skin. Only two patients developed subcutaneous CSF collection, which was managed conservatively. The patency of the anastomosis was proven by magnetic resonance angiography in all cases, and no ischemic complication suggesting chemical spasm of the STA due to the sealant occurred. With DuraSeal(TM), watertight dural closure can be obtained easily and safely in bypass surgery.

Prolonged and regionally progressive symptomatic cerebral hyperperfusion syndrome after superficial temporal artery-middle cerebral artery anastomosis in a patient with moyamoya disease

Background:The incidence of symptomatic hyperperfusion syndrome after superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis for patients with moyamoya disease (MMD) approaches 30%. In most cases, hyperperfusion occurs in a localized area and disappears within 1-2 weeks.Case Description:A 59-year-old female diagnosed with asymptomatic MMD for 4 months became rapidly symptomatic with transient ischemic attacks (TIAs). After left STA-MCA anastomosis surgery, she developed symptomatic hyperperfusion, initially (1-2 weeks after surgery) manifesting with severe headache and lesions located in the left basal ganglia. She then developed (2-5 weeks after surgery) aphasia and right hemiparesis caused by new hyperperfusion lesions located in the left frontal area. At discharge (7 weeks after surgery), she recovered fully without any remaining neurologic deficit and no ischemic lesions.Conclusion:This report details a rare case of a patient with MMD who presented with regionally progressive hyperperfusion lesions after STA-MCA anastomosis and symptoms that persisted for 5 weeks following surgery. Results from this case suggest that regional differences exist in the functional recovery of cerebrovascular reactivity (CVR) in a patient with rapidly progressive MMD.

Intraoperative assessment of STA-MCA bypass patency using near-infrared indocyanine green video-angiography: A preliminary study

Bypass patency is critical for patients undergoing superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. Near-infrared indocyanine green video-angiography (ICGA) is an excellent method to assess vessels during cerebrovascular surgery. The aim of the present study is to analyze the effectiveness of ICGA in patients undergoing STA-MCA anastomosis for moyamoya disease. This study was a retrospective review of case records and operation records of patients who underwent STA-MCA bypass for moyamoya disease at our institute. Concordance of ICGA with intraoperative micro-Doppler and postoperative angiography, whenever available, was assessed. In all, 22 STA-MCA anastomoses were performed in 13 patients. ICGA was used to assess patency in 14 surgeries (10 patients). No patient required revision of anastomosis following ICGA. Postoperative angiography was done in five anastomoses (three patients) at three months follow-up and correlated well with ICGA findings in all cases. ICGA is an effective technique to assess bypass patency during cerebrovascular surgery. Routine use of ICGA in cerebral bypass surgery improves graft patency and minimizes complications due to graft occlusion.

Superficial Temporal Artery-Middle Cerebral Artery Anastomosis for Internal Carotid Artery Occlusion by Subacute In-Stent Thrombosis after Carotid Artery Stenting

Alternative to carotid endarterectomy, carotid artery stenting (CAS) can be performed for symptomatic severe stenosis of internal carotid artery, especially for high-risk patients. Among several complications after CAS, subacute in-stent thrombosis is rare but important, because patient's condition can deteriorate rapidly. Subacute in-stent thrombosis with carotid artery occlusion can be managed by superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. We report two cases of STA-MCA anastomosis for internal carotid artery occlusion by subacute in-stent thrombosis after CAS.

The efficacy of superficial temporal artery–middle cerebral artery anastomosis in patients with moyamoya disease complaining of severe headache

Some patients with moyamoya disease complain of severe headache, which may be closely related to cerebral ischemia. The efficacy of superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis in these patients was evaluated by clinicoradiological studies. Of 117 consecutive patients with ischemic moyamoya disease, 25 complained mainly of severe headache (headache group) and 92 had no significant headache (nonheadache group). Intensity of headache was evaluated pre- and postoperatively. Furthermore, regional cerebral blood flow (rCBF) and cerebrovascular reactivity (CVR) were assessed pre- and postoperatively. The headache group was significantly younger than the nonheadache group. In a group corrected for the age distribution, preoperative rCBF and CVR were similar in headache and nonheadache groups. After STA-MCA anastomosis, 16 patients with headache experienced complete relief from headache, 7 patients showed remarkable improvements and discontinued medications for headache, and the remaining 2 patients had some alleviation of headache but sometimes required medication. In the headache group, the postoperative rCBF was significantly greater than the preoperative value. The postoperative rCBF in this group was also significantly greater than the postoperative rCBF in the nonheadache group. These data suggest that severe headache is one of the main symptoms in young patients with moyamoya disease probably related to cerebral circulatory disturbances. An STA-MCA anastomosis is effective in relieving headache in patients with ischemic moyamoya disease manifesting severe headache, probably by improving perfusion pressure and cerebral circulation.

Ivy signs on FLAIR images before and after STA-MCA anastomosis in patients with Moyamoya disease

Leptomeningeal high signal intensity (ivy sign) on fluid-attenuated inversion-recovery (FLAIR) MR imaging is one of the features of Moyamoya disease. However, the correlation between ivy sign and cerebral perfusion status has not been fully evaluated. To characterize ivy sign on FLAIR images in Moyamoya disease and compare this finding with hemodynamic alterations on perfusion single-photon emission CT (SPECT) obtained before and after bypass surgery. Sixteen patients with angiographically confirmed Moyamoya disease who underwent superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis were included in the study. The presence of ivy sign on FLAIR images was classified as 'negative', 'minimal' and 'positive'. We evaluated the relationship between ivy sign and findings of SPECT, including cerebral vascular reserve (CVR) before and after surgery. Minimal or positive ivy sign was seen in 13 (81%) of 16 patients, and 21 (66%) of 32 hemispheres. CVR in the areas with positive or minimal ivy sign was lower than that in the areas with negative ivy sign. After STA-MCA anastomosis, ivy sign disappeared or decreased in all 21 hemispheres demonstrating ivy sign. SPECT demonstrated apparent hemodynamic improvement in areas demonstrating disappearance or decrease of ivy sign. Ivy sign on FLAIR image is seen in areas with decreased cerebral perfusion. The sign is useful for non-invasive assessment of cerebral hemodynamic status before and after surgery.

Significance of Focal Cerebral Hyperperfusion as a Cause of Transient Neurologic Deterioration After Extracranial-Intracranial Bypass for Moyamoya Disease: Comparative Study With Non-Moyamoya Patients Using N-Isopropyl-p-[123I]Iodoamphetamine Single-Photon Emission Computed Tomography

Superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis prevents cerebral ischemic attack by improving cerebral blood flow in patients with occlusive cerebrovascular disease and hemodynamic compromise. Recent evidence suggests that focal cerebral hyperperfusion is a potential complication of this procedure for moyamoya disease. To clarify the exact differences in the incidence and clinical manifestations of this phenomenon between patients with and without moyamoya disease. N-isopropyl-p-[(123)I]iodoamphetamine single-photon emission computed tomography was performed 1 and 7 days after STA-MCA anastomosis on 121 hemispheres from 86 consecutive patients with moyamoya disease (2-67 years of age; mean, 34.3 years) and on 28 hemispheres from 28 non-moyamoya patients (12-67 years of age; mean, 56.5 years). The incidence of symptomatic hyperperfusion, defined as a significant focal increase in cerebral blood flow at the site of the anastomosis that is responsible for the apparent neurological signs, was compared between groups. Symptomatic cerebral hyperperfusion including mild focal neurological signs was seen in 25 patients with moyamoya disease (26 hemispheres, 21.5%) but in none of the patients without moyamoya disease (P = .0069). Multivariate analysis revealed that moyamoya disease was significantly associated with the development of symptomatic cerebral hyperperfusion (P = .0008). All patients with symptomatic hyperperfusion were relieved by intensive blood pressure control, and no patients suffered from permanent neurological deficit caused by hyperperfusion. Symptomatic cerebral hyperperfusion is a potential complication of STA-MCA anastomosis, especially in patients with moyamoya disease. Accurate diagnosis and adequate management of hyperperfusion are recommended, especially in patients with moyamoya disease.

Simultaneous Occurrence of Subarachnoid Hemorrhage and Epistaxis Due to Ruptured Petrous Internal Carotid Artery Aneurysm: Association With Transsphenoidal Surgery and Radiation Therapy -Case Report-

A 62-year-old woman presented with simultaneous subarachnoid hemorrhage (SAH) and massive epistaxis. The patient had been treated for pituitary prolactinoma by two transsphenoidal surgeries, gamma knife radiosurgery, and conventional radiation therapy since age 43 years. Cerebral angiography showed left petrous internal carotid artery (ICA) aneurysm with slight stenosis on the adjacent left petrous ICA. She underwent superficial temporal artery-middle cerebral artery (STA-MCA) double anastomosis with endovascular internal trapping without complication the day after onset. Postoperative course was uneventful; the patient did not develop symptomatic vasospasm, recurrent epistaxis, or cerebrospinal fluid rhinorrhea. Postoperative angiography demonstrated complete disappearance of the aneurysm with patent STA-MCA anastomosis. The patient was discharged 2 months after surgery without neurological deficit. The present case is extremely rare with simultaneous onset of SAH and epistaxis caused by ruptured petrous ICA aneurysm. The transsphenoidal surgeries and radiation therapies might have been critical in the formation of the petrous ICA aneurysm.

Intracerebral Hemorrhage From a Ruptured Aneurysm at the Site of Anastomosis 27 Years After Superficial Temporal Artery-Middle Cerebral Artery Bypass -Case Report-

A 77-year-old female presented with a very rare case of intracerebral hemorrhage (ICH) from a ruptured aneurysm at the site of the anastomosis 27 years after superficial temporal artery-middle cerebral artery (STA-MCA) bypass manifesting as sudden onset of unconsciousness and right hemiparesis. Computed tomography (CT) on admission demonstrated massive ICH in the left frontoparietal region. Magnetic resonance angiography showed good patency of the anastomosis and no obvious aneurysm, but three-dimensional CT (3D-CT) angiography revealed a small aneurysm at the site of the left STA-MCA anastomosis. Emergency evacuation of the hematoma was performed, and the aneurysm was trapped and resected after ligation. After the operation, she continued to exhibit deep consciousness disturbance. Unfortunately, her general condition grew steadily worse and she died 3 months later. Patients who undergo STA-MCA anastomosis should be carefully followed up by periodical imaging examinations. 3D-CT angiography is very useful to detect aneurysm formation at the anastomosis site.

Cerebral Hyperperfusion Syndrome Associated With Non-convulsive Status Epilepticus Following Superficial Temporal Artery-Middle Cerebral Artery Anastomosis -Case Report-

A 77-year-old man developed cerebral hyperperfusion syndrome with temporal deterioration of consciousness and worsening of left hemiparesis on the 6(th) postoperative day following superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis for right M(1) occlusion. Electroencephalography (EEG) revealed frequent ictal discharges in the right hemisphere, although convulsive seizures were not apparent. Administration of anticonvulsants was performed based on the diagnosis of non-convulsive status epilepticus (NCSE). Complete recovery from hyperperfusion syndrome was achieved with rapid improvement of EEG findings. The present case demonstrates the pathophysiological mechanism of hyperperfusion syndrome associated with NCSE after STA-MCA anastomosis.

Reversibility of Ischemic Findings on 3-T T2*-Weighted Imaging After Emergency Superficial Temporal Artery-Middle Cerebral Artery Anastomosis in Patients With Progressive Ischemic Stroke -Two Case Reports-

Vascular ischemic signs, i.e. multiple hypointense vessels in the ischemic territory, were identified by gradient echo-type 3-T T(2)*-weighted magnetic resonance (MR) imaging in 3 patients with acute ischemia due to major vessel occlusion. Emergency superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis was performed in 2 patients with progressive stroke caused by bleeding-type moyamoya disease or severe MCA stenosis. Both patients were initially treated conservatively, but their neurological signs deteriorated. 3-T T(2)*-weighted MR imaging detected funicular low signals in both patients indicating enhancement of cortical vessels or medullary veins. The area of the vascular ischemic signs was almost the same or smaller than the hypoperfusion area on perfusion-weighted MR imaging or single-photon emission computed tomography. Postoperatively, the vascular ischemic signs disappeared in both patients, suggesting a relationship with severe ischemia due to high-risk misery perfusion. Their postoperative course was uneventful, and MR imaging revealed no new cerebral ischemic lesions or cerebral hyperperfusion. The patient without surgery developed cerebral infarction in the area of the vascular ischemic signs. Vascular ischemic signs detected by 3-T T(2)*-weighted MR imaging may represent a new predictor of high-risk misery perfusion, and may disappear after STA-MCA anastomosis performed in the subacute stage.