Middle Cerebral Artery Anastomosis Research Articles

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.

Posterior Auricular Artery-Middle Cerebral Artery Bypass: A Rare Superficial Temporal Artery Variant with Well-developed Posterior Auricular Artery–Case Report

The posterior auricular artery (PAA) is one of the branches of the external carotid artery, but is usually too small for use as a donor artery for middle cerebral artery (MCA) territory revascularization. An extremely unusual case of PAA-MCA anastomosis was performed in a patient requiring MCA territory revascularization because the superficial temporal artery (STA) parietal branch was absent and the PAA was large enough. A 65-year-old man developed mild motor weakness in the right extremities caused by multiple small infarctions. Single photon emission computed tomography (CT) revealed deterioration of the vascular reserve capacity in the left MCA area. Cerebral angiography showed severe stenosis in the C2 portion of the left internal carotid artery, absence of the parietal branch of the left STA, and a well-developed PAA extending to the parietal area. The patient underwent STA (frontal branch)-MCA and PAA-MCA double anastomosis, and has suffered no stroke or transient ischemic attack. The STA with no bifurcation is known as a rare variation. The PAA also occurs with size variations but well-developed PAA is thought to be extremely rare. PAA can be used as a donor artery for MCA territory revascularization if the vessel size is suitable. Preoperative evaluation of the anatomy is mandatory for harvesting the arteries.

Urgent Extracranial-Intracranial Bypass in the Treatment of Acute Hemodynamic Ischemic Stroke: Case Report

Extracranial-intracranial (EC-IC) bypass surgery is performed to allow flow augmentation in selected cases of occlusive cerebrovascular disease. The majority of EC-IC bypasses are described as an elective procedure in the prevention of hemodynamic ischemic stroke. There is only limited and controversial experience of superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis performed under urgent circumstances as a treatment of acute cerebral ischemia. We describe a unique case of a 75-year-old patient presenting with acute progressive hemodynamic ischemia after carotid endarterectomy (CEA), which developed contralaterally to the performed CEA in the region of chronic internal carotid artery (ICA) occlusion. Urgent performance of a standard STA-MCA bypass rapidly improved the cerebral hemodynamic and had an excellent therapeutic effect. The patient had recovered completely within 4 weeks of surgery. The role of urgent EC-IC bypass for stroke treatment is discussed.

Semiquantitative analysis of indocyanine green videoangiography for cortical perfusion assessment in superficial temporal artery to middle cerebral artery anastomosis

Postoperative hyperperfusion may lead to severe neurological complications after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis. However, there are no reliable modalities to predict the occurrence of postoperative hyperperfusion during surgery. The purpose of this study is to evaluate whether a semiquantitative analysis of indocyanine green (ICG) videoangiography could be useful in predicting postoperative hyperperfusion after STA-MCA anastomosis. This study included seven patients who underwent STA-MCA anastomosis due to occlusive carotid artery diseases. During surgery, ICG videoangiography was performed before and after bypass procedures, and ICG intensity-time curves were semiquantitatively analyzed to evaluate hemodynamic changes by calculating maximum intensity, time to peak (TTP), and blood flow index (BFI). Maximum intensity significantly increased from 252.6 ± 132.5 to 351.7 ± 151.9 after bypass (p < 0.001). TTP was significantly shortened from 12.9 ± 4.4 s to 9.8 ± 3.7 s (p < 0.001). Furthermore, BFI significantly increased from 33.9 ± 28.1 to 74.6 ± 88.4 (p < 0.05). Postoperative hyperperfusion was observed in five of seven patients 1 day after surgery. The ratio of BFI before and after bypass procedures was significantly higher in patients with postoperative hyperperfusion than those without, 2.5 ± 1.1 and 1.5 ± 0.4, respectively (p = 0.013). These findings suggest that semiquantitative analysis of ICG videoangiography is helpful in predicting occurrence of hyperperfusion after STA-MCA anastomosis in patients with occlusive carotid artery diseases.

Cerebral revascularization with superficial temporal - middle cerebral artery anastomosis for complete carotid occlusion: An emerging modality for preventing recurrent stroke

Complete long segment carotid occlusion presents a treatment challenge. These patients cannot be managed adequately by endarterectomy or stenting. Despite best medical management, many continue to develop recurrent strokes. In this select group of patients, there may be role for flow augmentation techniques like superficial temporal-middle cerebral artery bypass. We report a patient who was thus successfully treated and remains asymptomatic. The relevant literature is reviewed.

The Usefulness of the Ivy Sign on Fluid-Attenuated Intensity Recovery Images in Improved Brain Hemodynamic Changes after Superficial Temporal Artery-Middle Cerebral Artery Anastomosis in Adult Patients with Moyamoya Disease

ObjectiveMR perfusion and single photon emission computerized tomography (SPECT) are well known imaging studies to evaluate hemodynamic change between prior to and following superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis in moyamoya disease. But their side effects and invasiveness make discomfort to patients. We evaluated the ivy sign on MR fluid attenuated inversion recovery (FLAIR) images in adult patients with moyamoya disease and compared it with result of SPECT and MR perfusion images.MethodsWe enrolled twelve patients (thirteen cases) who were diagnosed with moyamoya disease and underwent STA-MCA anastomosis at our medical institution during a period ranging from September of 2010 to December of 2012. The presence of the ivy sign on MR FLAIR images was classified as Negative (0), Minimal (1), and Positive (2). Regions were classified into four territories: the anterior cerebral artery (ACA), the anterior MCA, the posterior MCA and the posterior cerebral artery.ResultsIvy signs on preoperative and postoperative MR FLAIR were improved (8 and 4 in the ACA regions, 13 and 4 in the anterior MCA regions and 19 and 9 in the posterior MCA regions). Like this result, the cerebrovascular reserve (CVR) on SPECT was significantly increased in the sum of CVR in same regions after STA-MCA anastomosis.ConclusionAfter STA-MCA anastomosis, ivy signs were decreased in the cerebral hemisphere. As compared with conventional diagnostic modalities such as SPECT and MR perfusion images, the ivy sign on MR FLAIR is considered as a useful indicator in detecting brain hemodynamic changes between preoperatively and postoperatively in adult moyamoya patients.

もやもや病に対する血行再建術後の虚血合併症

Surgical revascularization for such conditions as superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis and/or indirect synangiosis using STA, dura mater, temporal muscle and pericranium has been commonly recognized as standard treatment for patients with moyamoya disease. However, various postoperative complications have been reported. Of these complications, postoperative ischemic stroke influence prognosis. We retrospectively reviewed patients with ischemic complications after revascularization, and assessed the incidence and mechanism of this ischemic complication. For this study, postoperative ischemic complication was defined as a newly developed infarction within two weeks after surgery, which was confirmed by follow-up imaging studies. This study included 84 hemispheres of 62 patients with moyamoya disease that underwent revascularization surgery between December 2006 and August 2011. Patients under four years of age were treated with indirect revascularization, from four to 39 of age with direct and indirect revascularization, and over 40 of age with direct revascularization. Ischemic complications were found in five patients (7.2%) of six hemispheres (6.4%). All patients were male. The age at the time of surgery ranged from three to 44 (mean 19.3 years). These infarctions were located in the cerebral hemisphere ipsilateral to the site of surgery in five, and contralateral in one. All of them occurred within four days after surgery. Preoperative angiograms revealed disappearance of the anterior cerebral artery (ACA) and middle cerebral artery (MCA) and marked development collateral vessels from posterior cerebral artery (PCA) in all patients, and stenosis of PCA in two patients. Two patients were two-year-old infants, who made rapid progress just before indirect revascularization surgery. In patients who exhibit dependence on PCA, careful postoperative management, such as control of blood pressure, is important to prevent these ischemic complications. It is also recommended that direct revascularization surgery be performed for any infants with rapid progression berore surgery.

An Efficient Microvascular Anastomosis Training Model Based on Chicken Wings and Simple Instruments

ObjectiveThe aim of this study is to introduce a microvascular training model based on use of materials that can be easily obtained from the daily surroundings.MethodsSimple microinstruments and a medical school laboratory microscope were used for anastomosis training. Chicken blood vessels were used as a material for this study. A long segment of blood vessel from the proximal brachial artery to the distal radial artery was used for training. End-to-side anastomosis was practiced first, and the training continued with end-to-end anastomosis of the appropriate segments.ResultsThe instruments used for setting up this model were simple and easy to use; therefore, the time required for preparation of the materials and dissection of the chicken wings was only approximately five to ten minutes. The characteristics of 20 chicken wings were analyzed. The length of the brachial artery to the radial artery was 8 - 10 cm. The average diameter of the brachial artery was 1.3 mm ± 0.2 mm and that of the radial artery was 1.0 mm ± 0.2 mm. Taking advantage of these characteristics, the proximal brachial artery was grafted to the radial artery for practice of end-to-side anastomosis.ConclusionsThis study suggests an effective and feasible method for microvascular anastomosis training using chicken wing arteries and simple microinstruments. This model may simulate the conditions of a superficial temporal artery to middle cerebral artery anastomosis surgery.

Early superficial temporal artery to middle cerebral artery bypass in acute ischemic stroke

ObjectiveTo evaluate the effects and safety of superficial temporal artery–middle cerebral artery (STA–MCA) anastomosis in the early stage after an acute ischemic event and the improvement of present symptoms in patients with intracranial atherosclerotic occlusive disease with stroke/stroke in progress. MethodsFrom 2006 to 2010, 20 patients (15 males and five females) with atherosclerotic cerebrovascular disease were treated with an STA–MCA bypass. All of the patients presented with an acute ischemic stroke or stroke in progress despite maximal medical treatment. The patients underwent an STA–MCA bypass within 7 days from symptom onset. The clinical outcome and hemodynamic study of the 20 patients were preoperatively and postoperatively investigated. A pooled analysis was performed, and the results were compared with those obtained from other delayed STA–MCA bypass studies. ResultsAmong the 20 patients who underwent an early STA–MCA bypass, fourteen (70%) patients achieved a good functional outcome (mRS 0, n=3; mRS 1, n=9; mRS 2, n=2). Prior to surgery, the mean basal regional cerebral blood flow (rCBF) and cerebrovascular reserve capacity (CVR) in the symptomatic hemisphere were 37.3±4.3ml/100g/min and −1.68±2.9%. The mean basal rCBF and CVR had significantly increased postoperatively, and no reperfusion-induced hemorrhage had occurred. In the pooled analysis, no significant differences were observed in the clinical outcome (P=0.328) or in the incidence of postoperative complications (P=0.516) between patients who underwent an early STA–MCA bypass and in patients who underwent a delayed STA–MCA bypass in previous studies. ConclusionsIn this study, which consisted of 20 carefully selected patients with acute ischemic stroke, an early STA–MCA bypass was safely and effectively performed, and in some cases, an early STA–MCA bypass resulted in rapid neurological improvement. An early STA–MCA bypass was beneficial in select patients who had acute ischemic stroke with imaging evidence of a small infarction.

Analysis of ischemic cerebral lesions using 3.0-T diffusion-weighted imaging and magnetic resonance angiography after revascularization surgery for ischemic disease

BackgroundCerebral revascularization surgery (CRS) is increasingly recognized as an important component in the treatment of complex cerebral vascular disease and tumors. CRS requires that the incidence of perioperative neurological complications should be minimized, because CRS for ischemic disease is often not the goal of treatment, but rather a prophylactic surgery. CRS carries the risk of focal postoperative neurological deficits. Little has been established concerning mechanisms of post-CRS ischemia. We used 3.0-T diffusion-weighted magnetic resonance imaging (DWI) and magnetic resonance angiography (MRA) to analyze the incidence and mechanism of ischemic lesions. MethodsWe studied the anterior circulation territory after 20 CRS procedures involving 33 vascular anastomosis procedures (13 double anastomoses and 7 single anastomoses) in 12 men and 8 women between June 2007 and October 2011. The operations included single or double superficial temporal artery–middle cerebral artery (STA–MCA) anastomosis to treat internal carotid artery/MCA occlusions or severe MCA stenosis. A combined STA–MCA anastomosis and indirect bypass were performed for moyamoya disease. Postoperative DWI and MRA were obtained in all patients between 24 and 96h after surgery to detect thromboembolism, hypoperfusion, or procedural ischemic complications and vasospasms of the donor STA. ResultsFollow-up DWI and MRA were carried out 1.8±0.6 days after CRS (range, 1–4 days). Temporary occlusion time for anastomoses averaged 18.9min (range, 16–32min). Asymptomatic new hyperintensities occurred in the ipsilateral hemisphere of 2 patients on postoperative DWI (10% patients/6.0% anastomoses), and 1 moyamoya patient (5.0% patients/3.0% anastomoses) developed a symptomatic hyperintensity in the ipsilateral occipital lobe in response to the operation. Two abnormal small (<5mm) cortical DWI lesions were caused by sacrifices of a small branch of the recipient MCA. ConclusionThis study is the first postoperative 3.0-T DWI study of CRS and related clinical events. The incidence of symptomatic postoperative DWI abnormalities was restricted to 1 moyamoya patient representing 5.0% of total patients and 3.0% anastomoses. Although some postoperative DWI abnormalities occurred, CRS was found to be safe with a low risk of symptomatic ischemia.

Efficacy of extracranial–intracranial revascularization for non-moyamoya steno-occlusive cerebrovascular disease in a series of 66 patients

Although there is uncertainty about whether extracranial–intracranial arterial bypass is useful for the treatment of steno-occlusive cerebrovascular disease in general, there is some argument for its continued use in particular patients. In the present study, we evaluated the efficacy of superficial temporal artery–middle cerebral artery (STA–MCA) anastomosis combined with encephalo-duro-myo-synangiosis (EDMS) in the treatment of non-moyamoya steno-occlusive cerebrovascular disease by retrospectively reviewing clinical and radiological data from 66 patients treated between January 2006 and April 2011. Forty-six double STA–MCA anastomoses and 20 single anastomoses were completed, and all remained patent in the perioperative phase, as confirmed by CT angiography. Postoperative CT perfusion imaging demonstrated immediate improvement in perfusion in the revascularized hemisphere. On discharge, 50 of the 66 patients (75.8%) had an improved National Institutes of Health Stroke Scale (NIHSS) score relative to preoperative values. After at least 6months of follow-up, 54 (88.5%) patients had improved NIHSS scores relative to discharge values. CT perfusion imaging showed significant improvement compared to post-operative images. Follow-up digital subtraction angiography confirmed that 95 of 96 (99%) anastomoses remained patent. There was no significant difference between the single and double bypasses in terms of either clinical or hemodynamic outcomes on the revascularized side. STA–MCA combined with EDMS was effective for the treatment of non-moyamoya steno-occlusive cerebrovascular disease with hemodynamic impairment. Hemodynamic evaluation before and after surgery may help identify patients in need of a bypass and may be useful for predicting outcome.

Perioperative complications of superficial temporal artery to middle cerebral artery bypass for the treatment of complex middle cerebral artery aneurysms

ObjectOnly a few studies have reported the risk of ischemic complications occurring when superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis is performed during surgery for complex MCA aneurysms. Subjects and methodsThis is a retrospective study of 10 patients (age 52–73) with MCA aneurysms treated with revascularization surgery. The aneurysms were 10–50mm in size (mean: 21mm). We studied the causes and frequency of ischemic complications by analyzing postoperative magnetic resonance imaging. ResultsPostoperative diffusion-imaging confirmed ischemic complications in six of the 10 patients (in two of the five ruptured aneurysms and in four of the five unruptured). The ischemic complications that observed were infarction of the lenticulostriate artery territory in three cases, cortical infarction in two cases, and cerebral infarction that was likely to be due to cerebral vasospasm in one case. In one case, both cortical infarction and infarction of the lenticulostriate artery territory were observed. The Glasgow Outcome Scale (GOS) scores at the time of discharge indicated good recovery (GR) and moderate disability (MD) in seven cases, severe disability (SD) in two cases, and death (D) in one case. ConclusionsThe present study suggests the possibility that STA–MCA anastamosis in surgeries for MCA aneurysms can be performed with comparatively better safety. However, the temporary occlusion time with this surgery is longer than that with a temporary clipping for aneurysmal surgery; thus, we believe that adequate countermeasures are required to prevent ischemic complications.

De novo ruptured aneurysm at the site of anastomosis after superficial temporal artery–middle cerebral artery anastomosis—Case report and literature review

De novo ruptured aneurysm at the site of anastomosis after superficial temporal artery–middle cerebral artery anastomosis—Case report and literature review

Extracranial–intracranial (EC–IC) bypass of symptomatic middle cerebral artery (MCA) total occlusion for haemodynamic impairment patients

A retrospective, single-centre, non-randomized study in the management of symptomatic middle cerebral artery (MCA) total occlusion disease to evaluate extracranial–intracranial (EC–IC) bypass as an intervention for patients with atherosclerotic MCA total occlusion, ischemic symptoms (transient ischemic attacks [TIAs]) or poor cerebral haemodynamics who had not responded well to maximal medical treatment was reported. Twenty-three patients were included in the study with the criteria of: having ischemic syndrome, for example, TIA; being associated with atherosclerotic MCA total occlusion disease (compatible with radiological assessment); being failed to respond to optimal medical therapy (e.g. antiplatelet therapy), indicating a repeat TIA or ischemic stroke attack was noted during maximal medical therapy; having poor cerebral perfusion on CT imaging; and having regional cerebrovascular reactivity (rCVR) of <20% when acetazolamide challenge was undergone. Patients had acute ischemic stroke or other major medical co-morbidities were excluded. No patient experienced any recurrent ischemic stroke during a mean follow-up period of 26.5 months except one patient suffered of immediate post-operative ischemic stroke because of the temporal vessel being clipped too long and the hypotension caused by anaesthesia. Post-operative follow-up imaging, which included MRI (MR angiography) and four-vessel digital subtraction angiography revealed a 100% patency of superficial temporal artery–middle cerebral artery (STA–MCA) anastomosis. No significant differences between observation periods (baseline status: 5.46 ± 5.13/85 ± 15; 0.5 month after surgery: 5.18 ± 5.29/85.91 ± 15.46 and 3 months after surgery: 5.09 ± 4.75/85.36 ± 12.27) were found for the neurological evaluations of NIHSS and Barthel Index (both expressed in mean ± SD) in all of the 23 patients. The annual risk of recurrent stroke was 0% after EC–IC bypass. However, studies with a larger scale are warranted to further confirm the effectiveness of EC–IC bypass.

Quantitative Angiographic Comparison With the OSIRIS Program Between the Direct and Indirect Revascularization Modalities in Adult Moyamoya Disease

Up-to-date, quantitative angiographic measurement of revascularization extent after bypass surgery has not been reported. To measure the extent of angiographic revascularization quantitatively 6 months postoperatively with the OSIRIS program (University Hospital of Geneva, version 3.1). A total of 75 bypass procedures were performed in 65 consecutive adult moyamoya disease patients, and 71 bypass surgeries in 61 adult moyamoya disease patients were studied 6 months postoperatively with angiography. We performed 5 different types of bypass surgeries: encephaloduroarteriosynangiosis (EDAS), superficial temporal artery-middle cerebral artery anastomosis (SMA), SMA with encephalomyosynangiosis (EMS), SMA with EDAS, and SMA with encephaloduroarteriomyosynangiosis (EDAMS). We also investigated single-photon emission computed tomography (SPECT) results after 6 months postoperatively and compared the angiographic revascularization extent with the SPECT results. The mean values for the extent of revascularization among 5 different bypass surgeries were as follows: 32.4% for EDAS only, 57.4% for SMA only, 58.4% for SMA with EMS, 66.1% for SMA with EDAS, and 70.8% for SMA with EDAMS. There was a statistically significant difference in the extent of revascularization among the 5 surgical modalities (P = .000) and between the EDAS-only group and various SMA groups (P = .000). Statistical analysis between angiographic revascularization extent and SPECT results demonstrated significant statistical correlation (P = .000). The extent of angiographic revascularization in adult moyamoya disease patients was highest in the SMA with EDAMS group and lowest in the EDAS-only group. In addition, angiographic revascularization extent was well correlated with the change in SPECT.

Abstract 2413: Postoperative Cerebral Hyperperfusion after Superficial Temporal Artery-Middle Cerebral Artery Anastomosis and Indirect Synangiosis in Moyamoya Disease: PET and SPECT Study

Background Postoperative cerebral hyperperfusion is known to occur after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis and indirect synangiosis in moyamoya disease. However, the clinical features and pathophysiology still remain to be elucidated. Objective To clarify the incidence and pathogenesis of postoperative hyperperfusion after surgical revascularization for moyamoya disease. Methods This study included 41 consecutive patients (58 surgeries) who underwent STA-MCA anastomosis and indirect synangiosis for moyamoya disease. Their medical records were evaluated to identify clinical features of postoperative hyperperfusion. Using 15O-gas positron emission tomography (PET), cerebral hemodynamics and metabolism were determined before surgery in all patients. Using 123I-IMP single photon emission computed tomography (SPECT), cerebral blood flow was qualitatively measured on Day 0, 2, and 7 after surgery in all patients. A multivariate logistic regression analysis was conducted to identify the predictors for postoperative hyperperfusion. Results Postoperative hyperperfusion was observed in 29 (50.0%) of 58 operated sides. In pediatric patients, it was quite rare. Thus, symptomatic and asymptomatic hyperperfusion occurred in 1 (5%) and 3 (15%) of 20 sides, respectively. In adult cases, however, symptomatic and asymptomatic hyperperfusion were significantly more often (P=0.0037 and P=0.026, respectively) and were noted in 12 (31.5%) and 13 (34.2%) of 38 sides, respectively. A logistic regression analysis revealed that cerebral blood volume (CBV) increase before surgery was a significant predictors for symptomatic hyperperfusion in adults (P=0.036). Furthermore, hyperperfusion immediately after surgery was at significantly higher risk to be symptomatic (7/9=77.7%, P=0.033). Conclusions Postoperative hyperperfusion after STA-MCA anastomosis in adult moyamoya disease is not rare. Preoperative CBV increase was closely related to the occurrence of symptomatic hyperperfusion in adult cases. Hyperperfusion immediately after surgery may easily cause neurological deficits or other symptoms. Precise evaluation of cerebral hemodynamics and metabolism before and after surgery would be valuable to predict postoperative hyperperfusion and prevent perioperative complications.

Disappearance of aneurysms associated with moyamoya disease after STA–MCA anastomosis with encephaloduro myosynangiosis

Moyamoya disease is a rare cerebrovascular disease characterized by steno-occlusive vasculopathy affecting the terminal internal carotid arteries. Although the effect of direct arterial bypass on the prevention of recurrent haemorrhage or ischemic events in patients with hemorrhagic moyamoya disease has been demonstrated, disappearance of aneurysms associated with moyamoya disease has rarely been reported. In this study, we present two patients with aneurysms associated with moyamoya disease. After superficial temporal artery to middle cerebral artery anastomosis combined with encephaloduro myosynangiosis, the aneurysms on the moyamoya vessels disappeared, which was confirmed by follow-up angiography.

EmergencyIn SituBypass during Middle Cerebral Artery Aneurysm Surgery: Middle Cerebral Artery-Superficial Temporal Artery Interposition Graft-Middle Cerebral Artery Anastomosis

Many reports have been published on complications related to middle cerebral artery (MCA) aneurysm surgical clipping procedures. We report an emergency intracranial in situ bypass surgery case which was performed as a rescue procedure after aneurysmal neck laceration during clipping of an MCA large aneurysm. In this case, we performed in situ M3-superficial temporal artery (STA) interposition graft-M3 bypass procedure. If a STA-MCA anastomosis is not available under MCA flow obstruction, we can consider an emergency in situ MCA-MCA bypass procedure with or without an STA interposition graft.

General anesthetic management of Prader-Willi syndrome patient undergoing middle cerebral artery-superficial temporal artery anastomosis

We experienced a case of a 17-year-old patient with genetically proven Prader-Willi syndrome who had left middle cerebral artery-left superficial temporal artery anastomosis surgery under general anesthesia with a non-depolarizing muscle relaxant. Prader-Willi syndrome is a genetic disorder associated with hypotonia. Using general anesthesia with a non-depolarizing muscle relaxant in these patients is difficult due to hypotonia. We, therefore, monitored the status of muscle relaxation with a train of four (TOF, TOF-Watch®, Organon, Ireland) during general anesthesia. Unlike infants, adolescents can have the muscle relaxation monitor on their body surface. Because lengthy, complex microsurgery was required for this vascular surgery, we had to use a muscle relaxant. However, when using a muscle relaxant, predicting the extent of the effect and the recovery time are difficult. The TOF ratio was 0.85 in the preanesthetic state. Anesthetic induction was done using the total intravenous anesthesia of the target concentration infusion method. Propofol target concentration at 4 µg/ml was initially injected. Remifentanil was injected at 0.15 µg/kg/min. Five minutes after an atracurium 15 mg injection, the TOF watch count was still at 2. Therefore, an additional 15 mg of atracurium was injected for intubation. When the TOF watch count was over 4, during the operation, an additional 5 mg of atracurium was injected. For the entire surgery, 65 mg of atracurium was used. The operation lasted for 2 hours and 50 minutes. After the operation, when the TOF ratio was 0.85, glycopyrrolate 0.4 mg and pyridostigmine 15 mg were injected. The endotracheal tube was removed once the patient regained spontaneous respiration and was fully awake. After extubation, the patient was arousable using painful stimulation. In the post anesthetic care unit, the patient had no respiratory problem and his TOF ratio was 0.85. The patient was then transferred to the general ward. Prader-Willi syndrome is a genetic disorder classically characterized by hypotonia, hypomentia, and hypogonadism that is associated with obesity [1]. The cause of hypotonia, muscle weakness, and motor problems in Prader-Willi patients are not clear. The contributing factors may be the abnormal body composition found in Prader-Willi patients, an increase in fat mass and a decrease in muscle mass, and, possibly, some degree of neuromuscular abnormality [2]. It has been reported that the motor problems are still present in childhood and adulthood, which causes the decrease in physical activity in Prader-Willi patients [3]. Thus, the hypotonia makes the choice of muscle relaxant difficult. Anesthetic management using atracurium and rocuronium have been reported [4,5]. However, few reports are available on using the intraoperative monitoring of the neuromuscular blockade for Prader-Willi patients. In this case, though the patient had hypotonia, anesthesia was successfully used with a dose adjusted muscle relaxant using the TOF watch.

External Carotid Artery Stenting and Superficial Temporal Artery to Middle Cerebral Artery Anastomosis for Internal Carotid Artery Occlusion With External Carotid Artery Severe Stenosis

Superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis may have inadequate effects in patients with internal carotid artery (ICA) occlusion and severe stenosis of the ipsilateral external carotid artery (ECA), because poor blood flow in the STA leads to insufficient flow to the MCA. In these patients, dilation of the stenotic ECA is required to improve the blood flow in the STA before STA-MCA anastomosis. A 71-year-old man presented with left hemiparesis and dysarthria. Magnetic resonance imaging revealed an old watershed infarction in the right cerebral hemisphere. Right carotid angiography showed right ICA occlusion and severe ipsilateral ECA stenosis. Single photon emission computed tomography (SPECT) demonstrated severe hemodynamic insufficiency in the right MCA territory. Instead of endarterectomy of the ECA, angioplasty and stenting (CAS) for ECA was performed to ensure adequate blood flow in the STA, due to the history of myocardial infarction and bifurcation of the common carotid artery at a high level (C2 level). Then STA-MCA anastomosis was performed 1 month later. Postoperative SPECT demonstrated marked improvement of hemodynamic insufficiency in the right MCA territory. After treatment, the patient had no ischemic events. This case suggests external CAS together with STA-MCA anastomosis is a good therapeutic option for a patient with symptomatic ICA occlusion and severe stenosis of the ipsilateral ECA if external CEA is difficult to perform.