UNASSIGNED: This study aimed to examine the effect of newly developed scissors-attached micro-forceps in superficial temporal artery-to-middle cerebral artery (STA-MCA) anastomosis for moyamoya disease (MMD).
UNASSIGNED: Of 179 consecutive STA-MCA anastomoses on 95 hemispheres of 71 MMD patients at the University of Fukui Hospital between 2009 and 2023, 49 anastomoses on 26 hemispheres of 21 patients were enrolled in this retrospective cohort clinical trial intraoperative indocyanine green video-angiography did not demonstrate bypass patency in three anastomoses in two patients who were excluded. Twenty-one anastomosis in 19 hemispheres of 16 patients were performed using the conventional micro-forceps (conventional group, CG), and 25 anastomoses in 22 hemispheres of 19 patients were performed using scissors-attached micro-forceps (scissors group, SG). A small infarction near the anastomotic site detected using postoperative diffusion-weighted imaging was defined as anastomotic site infarction (ASI). Factors affecting the occurrence of ASI were examined by univariate, logistic regression, and receiver operating curve (ROC) analysis.
UNASSIGNED: There were no significant differences in clinical parameters such as age, sex, number of sacrificed branches, number of sacrificed large branches, and number of sutures between the CG and SG. However, the clamp time and occurrence of ASI were significantly lower in the SG than in the CG. Logistic regression analysis revealed that the clamp time was the only significant factor predicting the occurrence of ASI. A receiver operating curve analysis also revealed that the clamp time significantly predicted the occurrence of ASI (area under the curve, 0.875; cutoff value, 33.2 min).
UNASSIGNED: The newly developed scissors-attached micro-forceps could significantly reduce the clamp time and occurrence of ASI in STA-MCA anastomosis for MMD.

POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes) syndrome is a rare multisystem disease characterized by plasma cell dyscrasia and overproduction of vascular endothelial growth factor, which is related to disease activity. Recent treatment strategies have improved survival of patients suffering from this disorder; however, ischemic stroke remains a poor prognostic factor. POEMS patients with ischemic stroke frequently develop cerebral large artery stenosis/occlusion, followed by progressive stroke. Post literature review, we present an ischemic stroke case of quasi-moyamoya disease linked with this syndrome that was successfully treated with surgical revascularization. A 41-year-old woman diagnosed with POEMS syndrome developed progressive ischemic stroke due to quasi-moyamoya disease, despite decreased vascular endothelial growth factor level with lenalidomide and dexamethasone treatment. She underwent superficial temporal artery to middle cerebral artery bypass with encephalo-duro-myo-synangiosis bilaterally. The postoperative course was uneventful. Two years and five months after the stroke, neuroimaging demonstrated bypass patency, neovascularization after encephalo-duro-myo-synangiosis, and no recurrence of stroke. Our case is the first to report successful surgical revascularization for a POEMS patient. Surgical revascularization may be a useful treatment option for patients with quasi-moyamoya disease associated with POEMS syndrome, especially for those who develop refractory ischemic stroke despite reduced vascular endothelial growth factor level.

OBJECTIVE: Abnormal collateral channels, so-called moyamoya vessels, play a critical role to compensate cerebral ischemia, but carry the risk for hemorrhagic stroke in moyamoya disease (MMD). The present study was aimed to clarify if superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis and encephalo-myo-duro-arterio-pericranial synangiosis (EDMAPS) can efficiently regress the abnormal collateral channels in MMD patients.
METHODS: This study included 92 hemispheres of 61 MMD patients who underwent STA-MCA anastomosis combined with EDMAPS between 2013 and 2019. There were 17 children and 44 adults. We retrospectively analyzed the findings on cerebral angiography before and 3 to 6 months after surgery, including Suzuki\'s angiographical stage, the development of surgical collaterals, and the extent of abnormal collateral channels such as lenticulostriate, thalamic, and choroidal channels.
RESULTS: Following surgery, no pediatric and adult patients experienced any stroke during follow-up periods (40.2±25.5 and 54.9±19.7 months, respectively). Suzuki\'s stage significantly advanced in both adult and pediatric patients after surgery (P=0.042 and P<0.001). In adult patients, all of the lenticulostriate, thalamic, and choroidal channels significantly regressed after surgery (P<0.001, P=0.012, and P=0.004, respectively). In pediatric patients, however, lenticulostriate and choroidal channels significantly regressed (P=0.005 and P=0.034, respectively). Correlation analysis revealed that the development of surgical collaterals determined the postoperative regression of choroidal channels (P<0.001).
CONCLUSIONS: STA-MCA anastomosis and EDMAPS may be one of the most effective procedures to widely provide surgical collaterals to the operated hemispheres and prevent not only ischemic but also hemorrhagic stroke by regressing the hemorrhage-prone abnormal collateral channels in MMD.

BACKGROUND: The patency of cranial bypasses must be carefully evaluated during and after the microsurgical procedure. Although, several imaging techniques are used to evaluate the patency of bypasses, their findings are sometimes difficult to interpret.
OBJECTIVE: The goal of this study was to assess the consistency of different diagnostic modalities for evaluating intracranial bypass patency.
METHODS: This prospective study included 19 consecutive patients treated with EC-IC or IC-IC bypass for MoyaMoya disease (MMD) or complex/giant aneurysms between June 2016 and June 2018. In the early postoperative period (<7 days), all patients had transcranial Doppler (TCD), CT angiography (CTA) and MRA to demonstrate patency of anastomoses and to confirm exclusion of the aneurysm. When findings of anastomosis patency differed between these techniques, conventional angiography was performed.
RESULTS: All anastomoses were patent on indocyanine green videoangiography at the end of microsurgical procedure. The results of noninvasive postoperative exams were consistent to demonstrate the patency of anastomoses in 13 patients. In 4 patients, a discrepancy in patency of anastomoses arose between TCD, CTA and MRI in the early postoperative period. In 2 other patients, the interpretation of bypass patency remained inconclusive before the decision to occlude the aneurysm. In these 6 patients, a significant edema was noted in 2 cases, a postoperative subdural hematoma in 1 case, a low flow in the anastomosis in 1 case and vasospasm in 2 cases. The anastomosis was patent on the conventional angiography in five patients.
CONCLUSIONS: Noninvasive imaging techniques provide useful data about the patency but their findings should be carefully interpreted due to local anatomical, physiological, and pathological factors. In case of discrepant findings, conventional angiography including supraselective catheterization of the donor vessel is suggested.

The superficial temporal artery (STA) to middle cerebral artery (MCA) bypass is an effective treatment procedure for steno-occlusive severe ischemic disease of the anterior circulation. The formation of an aneurysm at the anastomosis site is a rare complication, and the mechanism underlying this condition and the appropriate treatment strategy, have not yet been established. We describe a case of an unruptured anastomosis aneurysm that was treated by endovascular embolization 7 years after bypass surgery.
A 62-year-old woman presented with slurred speech, with magnetic resonance imaging and angiography showing multiple infarctions in her left cerebral hemisphere and severe stenosis in the left internal carotid artery and left MCA. An STA-MCA anastomosis was performed without neurologic sequelae. Five years later, follow-up magnetic resonance imaging showed that an aneurysm had formed at the MCA side of the anastomosis site. After 2 years, the saccular aneurysm had grown and was embedded in the brain parenchyma. Because the patient had experienced repeated problems with surgical wound healing, an endovascular intervention was performed, achieving obliteration of the aneurysm by coil embolization.
Endovascular treatment is a feasible and efficacious treatment option for an aneurysm at the anastomosis site of an STA-MCA bypass.

Harvesting the superficial temporal artery (STA) is the first difficult step in extracranial-intracranial bypass surgery. There are various methods and instruments for harvesting the STA. We used the Lone Star (LS) retractor system for harvesting the STA. The LS retractor system is used in other surgical specialties. The LS retractor system consists of the retractor ring (14.1 cm × 14.1 cm) and elastic stays (5-mm sharp hook). The retractor ring can be used to adjust to the operative field. Retracting the loose connective tissue around the STA by the elastic stays can make harvesting the STA easy and safe. After harvesting the STA, retracting the skin and muscle by the elastic stays is useful for hemostasis during intracranial surgery and anastomosis. We used the LS retractor system in 26 consecutive patients to perform STA-MCA anastomosis between November 2015 and August 2018. All STAs were harvested without complications or injuries. The LS retractor system is a safe and useful method for harvesting the STA.

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 β 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.

High-flow extracranial-intracranial bypass is associated with a significant risk of ischemic stroke. The goal of this study is to evaluate the effectiveness of STA-MCA bypass preceding a high-flow bypass as a means of protecting the brain from ischemia during the high-flow bypass anastomosis in patients with otherwise untreatable aneurysms.
This prospective study included 10 consecutive patients treated for complex/giant aneurysm using a previous combined STA-MCA bypass and high-flow EC-IC bypass between June 2016 and January 2018 when classical endovascular or microsurgical exclusion was estimated too risky. Early cranial Doppler, MRI, CT scan, and conventional angiography were performed in each patient to confirm patency of bypasses, measure flow in the anastomoses, detect any ischemic lesions, and evaluate exclusion of the aneurysm.
The mean age at treatment was 55 years (range 34 to 67). The mean time of microsurgical procedure was 11 h (range 9 to 12). In all patients, the high-flow bypass was patent intraoperatively and complete occlusion of aneurysm was obtained. No ischemic lesions were noted on early MRI. One patient died from a large hemispheric infarction related to a common carotid artery dissection 10 days after the microsurgical procedure and immediate postoperative epidural hematoma was noted in one other patient.
In this study, we described the use of a protective STA-MCA bypass, performed prior to the high-flow bypass, in order to reduce the risk of perioperative ischemic lesions without increasing the morbidity of the surgical procedure. This treatment paradigm was feasible in all ten patients without complications related to the STA-MCA anastomosis.

OBJECTIVEEffectively retaining the patency of the extracranial-intracranial (ECIC) bypass is one of the most important factors in improving long-term results; however, the factors influencing bypass patency have not been discussed much. Therefore, the authors investigated factors influencing the development of the bypass graft.METHODSIn this retrospective study, the authors evaluated 49 consecutive hemispheres in 47 adult Japanese patients who had undergone ECIC bypass for chronic steno-occlusive cerebrovascular disease. To evaluate objectively the development of the ECIC bypass graft, the change in the area of the main trunk portion of the superficial temporal artery (STA) from before to after bypass surgery (postop/preop STA) was measured. Using the interquartile range (IQR), the authors statistically analyzed the factors associated with excellent (> 3rd quartile) and poor development (< 1st quartile) of the bypass graft.RESULTSThe postop/preop STA ranged from 1.08 to 6.13 (median 1.97, IQR 1.645-2.445). There was a significant difference in the postop/preop STA between the presence and absence of concurrent diabetes mellitus (p = 0.0432) and hyperlipidemia (0.0069). Furthermore, logistic regression analysis revealed that only concurrent diabetes mellitus was significantly associated with poor development of the bypass graft (p = 0.0235).CONCLUSIONSDiabetes mellitus and hyperlipidemia influenced the development of the ECIC bypass graft. In particular, diabetes mellitus is the only factor associated with poor development of the bypass graft.

Intravenous recombinant tissue-type plasminogen activator (rt-PA) with/without endovascular treatment is not as effective in atherosclerotic steno-occlusive acute ischemic stroke. Urgent superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis is effective to some extent in progressing stroke, but the safety of STA-MCA anastomosis soon after rt-PA therapy is unknown. Our aim was to clarify the safety of STA-MCA anastomosis within 24 h after intravenous rt-PA.
From 2005 to 2015, rt-PA was administered to 225 patients presenting with acute ischemic stroke according to the Japanese Stroke Guidelines, in our institution. Five patients underwent urgent STA-MCA anastomosis after rt-PA administration with or without endovascular recanalization. Clinical time course, surgical complications, and patients\' prognosis were investigated.
The average of patient age was 65.4 years (range 49-77 years); three patients had internal carotid artery occlusion, and two patients had middle cerebral artery occlusion. The median National Institutes of Health Stroke Scale score on admission was 12.4 (range 6-17 points) and operation occurred 10.6 h (range 5.3-23.6 h) after intravenous rt-PA administration. Hemostasis was achieved during standard STA-MCA anastomosis, and there were no hemorrhagic complications.
In our consecutive cases, urgent STA-MCA anastomosis after at least 5.3 h after intravenous rt-PA was performed safely without hemorrhagic complications.