Superficial Temporal Artery To Middle Cerebral Artery Anastomosis Research Articles

Intraoperative monitoring of cerebrospinal fluid gas tension and pH before and after surgical revascularization for moyamoya disease.

This study aimed to directly measure cerebrospinal fluid (CSF) gas tensions and pH before and after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis for moyamoya disease. This study included 25 patients with moyamoya disease who underwent STA-MCA anastomosis combined with indirect bypass onto their 34 hemispheres. About 1 mL of CSF was collected before and after bypass procedures to measure CSF partial pressure of oxygen (PCSFO2), CSF partial pressure of carbon dioxide (PCSFCO2), and CSF pH with a blood gas analyzer. As the controls, the CSF was collected from 6 patients during surgery for an unruptured cerebral aneurysm. PCSFO2 and PCSFCO2 were expressed as the ratio to partial pressure of oxygen (PaO2) and partial pressure of carbon dioxide (PaCO2), respectively. PCSFO2/PaO2 was 0.79 ± 0.14 in moyamoya disease, being lower than 1.10 ± 0.09 in the controls (P < 0.0001). PCSFCO2/PaCO2 was 0.90 ± 0.10 in moyamoya disease, being higher than 0.84 ± 0.07 in the controls (P = 0.0261). PCSFO2/PaO2 was significantly lower in pediatric patients than in adult patients and in the hemispheres with reduced cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) to acetazolamide than in those with normal CBF but reduced CVR. STA-MCA anastomosis significantly increased PCSFO2/PaO2 from 0.79 ± 0.14 to 0.86 ± 0.14 (P < 0.01) and reduced PCSFCO2/PaCO2 from 0.90 ± 0.10 to 0.69 ± 0.16 (P < 0.0001). There was no difference in CSF pH between moyamoya disease and the controls. PCSFO2/PaO2 was significantly lower in moyamoya disease than in the controls. Its magnitude was more pronounced in pediatric patients than in adult patients and depends on the severity of cerebral ischemia. STA-MCA anastomosis carries dramatic effects on CSF gas tensions in moyamoya patients. CSF may be a valuable biomarker to monitor the pathophysiology of cerebral ischemia/hypoxia in moyamoya disease.

Effects of superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis on the cerebrospinal fluid gas tensions and pH in hemodynamically compromised patients.

This study was aimed to directly measure cerebrospinal fluid (CSF) gas tensions and pH before and after STA-MCA anastomosis for occlusive carotid artery diseases to investigate its direct effects on the ischemic brain. This study included 9 patients who underwent STA-MCA anastomosis on the basis of CBF studies. About 1mL of CSF was collected before and after bypass procedures, and CSF pH, CSF PO2, and CSF PCO2 were measured with a blood gas analyzer. As the controls, the CSF was collected from 6 patients during surgery for unruptured cerebral aneurysm. CSF PO2 and CSF PCO2 were expressed as the ratio to PaO2 and PaCO2, respectively. Before bypass procedure, CSF PO2/PaO2 was 0.88 ± 0.16, being lower than the controls (1.10 ± 0.09; P = 0.005). CSF PCO2/PaCO2 was 0.93 ± 0.13, being higher than the controls (0.84 ± 0.06; P = 0.039). Ipsilateral-to-contralateral CBF ratio had a positive correlation with CSF PO2/PaO2 (P = 0.0028) but a negative correlation with the CSF PCO2/PaCO2 (P = 0.0045). STA-MCA anastomosis increased CSF pH from 7.402 ± 0.133 to 7.504 ± 0.126 (P = 0.0011) and CSF PO2/PaO2 from 0.88 ± 0.16 to 1.05 ± 0.26 (P = 0.018) but decreased CSF PCO2/PaCO2 from 0.93 ± 0.13 to 0.70 ± 0.17 (P = 0.0006). The severity of cerebral ischemia before surgery is intensely reflected in the gas tensions and pH of the CSF. STA-MCA anastomosis carries dramatic effects on CSF gas tensions and pH in hemodynamically compromised patients. CSF would be a valuable surrogate biomarker to monitor the severity of cerebral ischemia.

Effect of newly developed scissors-attached micro-forceps on the recipient clamp time and occurrence of anastomotic site infarction after bypass surgery for moyamoya disease.

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). 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. 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). The newly developed scissors-attached micro-forceps could significantly reduce the clamp time and occurrence of ASI in STA-MCA anastomosis for MMD.

Bypass Surgery for Moyamoya Disease, Part 1: Special Considerations and Techniques

In this review article, the author describes the eligible patients, concept, surgical technique, and long-term outcome of the superficial temporal artery to middle cerebral artery(STA-MCA)anastomosis and the ultimate indirect bypass, called encephalo-duro-myo-arterio-pericranial synangiosis(EDMAPS)for adult moyamoya disease, in addition to the novel diagnostic criteria. The procedure dramatically improves or normalizes the cerebral blood flow immediately after surgery and thus contributes to preventing ischemic complications during and after surgery. However, the arterial wall of these patients is extremely thin and fragile; therefore, the surgeons should be trained extensively and have absolute confidence in their ability to perform this procedure. The surgeons should be aware that STA-MCA anastomosis frequently induces the hyper-perfusion phenomenon in adult patients with moyamoya due to prolonged cerebral ischemia. The extent of craniotomy determines the amount of surgical collaterals after indirect surgery; thus, a wide craniotomy including most of the frontal area, especially the medial frontal area, is critical to improve the postoperative prognosis. This procedure can markedly diminish the dangerous periventricular collateral channels and provides excellent long-term outcomes for up to 20 years after surgery. Long-term follow-ups longer than 20 years are important to monitor the patients with this unique and peculiar disease.

Ameliorative Effects of Combined Revascularization Surgery on Abnormal Collateral Channels in Moyamoya Disease

ObjectAbnormal 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. MethodsThis 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. ResultsFollowing 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). ConclusionSTA-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.

Late (5-20 years) outcomes after STA-MCA anastomosis and encephalo-duro-myo-arterio-pericranial synangiosis in patients with moyamoya disease.

Surgical revascularization is known to reduce the incidence of further ischemic and hemorrhagic events in patients with moyamoya disease, but the majority of previous studies report only short-term (< 5 years) outcomes. Therefore, in this study the authors aimed to evaluate late (5-20 years) outcomes of moyamoya patients after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis and indirect bypass (encephalo-duro-myo-arterio-pericranial synangiosis [EDMAPS]). Cumulative incidences of late morbidity/mortality and disease progression were evaluated among 93 patients who underwent STA-MCA anastomosis and EDMAPS. All of the patients were prospectively followed up for longer than 5 years postsurgery (10.5 ± 4.4 years). There were 35 pediatric and 58 adult patients. Initial presentation included transient ischemic attack/ischemic stroke in 80 patients and hemorrhagic stroke in 10 patients, and 3 patients were asymptomatic. Surgery was performed in a total of 141 hemispheres. Follow-up MRI/MRA was performed within a 6- or 12-month interval during the follow-up periods. During the follow-up periods, 92/93 patients were free from any stroke or death, but 1 patient had a recurrence of hemorrhagic stroke (0.10% per patient-year). Disease progression occurred in the territory of the contralateral carotid or posterior cerebral artery (PCA) in 19 hemispheres of 15 patients (1.5% per patient-year). The interval between initial surgery and disease progression varied widely, from 0.5 to 15 years. Repeat bypass surgery for the anterior and posterior circulation resolved ischemic attacks in all 10 patients. The study results indicate that STA-MCA anastomosis and EDMAPS would be the best choice to prevent further ischemic and hemorrhagic stroke for longer than 10 years on the basis of the demonstrated widespread improvement in cerebral hemodynamics in both the MCA and ACA territories in the study patients. However, after 10 years postsurgery regular follow-up is essential to detect disease progression in the territory of the contralateral carotid artery and PCA and prevent late cerebrovascular events.

Preoperative evaluation of moyamoya spontaneous anastomosis of combined revascularization donor vessels in adults by duplex ultrasonography

Objective: To evaluate the preoperative diagnostic value of duplex ultrasonography in moyamoya spontaneous anastomosis of combined revascularization donor vessels in adults.Methods: A total of 99 preoperative adult patients who underwent superficial temporal artery-to-middle cerebral artery (STA-MCA) anastomosis were retrospectively analyzed. Each side of the cerebral hemisphere was examined as a separate procedure. A total of 198 cerebral hemispheres were divided into three groups: a collateral, non-collateral, and control group based on digital subtraction angiography (DSA). Hemodynamic parameters, including peak systolic velocity (PSV), end diastolic velocity (EDV), and resistance index (RI) were analyzed.Results: There were only four of cases (5%, 4/198) of STA spontaneous anastomosis, whereas those of maxillary artery (MA) anastomosis were 44 (23.7%, 44/186). Compared with the control group, MA PSV and EDV of the collateral group increased significantly, while RI decreased significantly (p < .05). The area under the curve (AUC) of MA RI was 0.654. As a predictor of MA spontaneous anastomosis, duplex ultrasonography had high specificity but poor sensitivity. In collateral group, PSV and EDV detected two weeks post-surgery were significantly higher than those detected pre-operatively (PSV: p = .018, EDV: p = .025). By contrast, there were no significant difference of the PSV and EDV detected six months post-surgery compared with pre-operation (PSV: p = .450, EDV: p = .099). Additionally, MA RI in two weeks after the surgery was comparable with preoperative values.Conclusions: Duplex ultrasonography could be applied to evaluate the adult moyamoya spontaneous anastomoses of MA preoperatively. Despite its poor sensitivity, this diagnostic modality is still reliable and specific. STA-MCA anastomosis combined with EDMS did not affect MA pre-operative spontaneous anastomosis.

Brain Infarct and Abscess—A Very Common Disease and a Rare Association

To explore the effectiveness of superficial temporal artery–to–middle cerebral artery (STA-MCA) anastomosis in treating moyamoya disease (MMD).A total of 30 patients with MMD (hemorrhagic type, n = 13; ischemic type, n = 17) who had undergone STA-MCA anastomosis were enrolled in this study (anastomosis group). Cerebral blood flow was evaluated before and after surgery using cerebral angiography and computed tomography (CT) perfusion imaging. In addition, 27 patients with MMD (hemorrhagic type, n = 11; ischemic type, n = 16) who had received only conservative treatment were enrolled as the control group. Patients in both the anastomosis group and the control group were followed up for 5 years, and the incidences of cerebral hemorrhage and cerebral ischemia were analyzed. Blood samples were collected in both groups before and after treatment. Mononuclear cells were separated by density gradient centrifugation. After labeling with 3 direct fluorescent antibodies (CD133, CD34, and vascular endothelial growth factor receptor 2), the number of endothelial progenitor cells (EPCs) was detected using flow cytometry.Cerebral blood flow was remarkably improved after STA-MCA anastomosis. The incidences of cerebral hemorrhage and cerebral ischemia were significantly lower in the anastomosis group than in the control group. The number of EPCs showed no significant change before and after treatment in the control group; in contrast, it was decreased significantly after surgery in the anastomosis group.STA-MCA anastomosis can reduce the number of EPCs in MMD patients, lower the risk of rebreeding, and improve cerebral ischemic attacks.

Effectiveness of Superficial Temporal Artery-to-Middle Cerebral Artery Anastomosis in Treating Moyamoya Disease by Reducing Endothelial Progenitor Cells

To explore the effectiveness of superficial temporal artery-to-middle cerebral artery (STA-MCA) anastomosis in treating moyamoya disease (MMD). A total of 30 patients with MMD (hemorrhagic type, n= 13; ischemic type, n= 17) who had undergone STA-MCA anastomosis were enrolled in this study (anastomosis group). Cerebral blood flow was evaluated before and after surgery using cerebral angiography and computed tomography (CT) perfusion imaging. In addition, 27 patients with MMD (hemorrhagic type, n= 11; ischemic type, n= 16) who had received only conservative treatment were enrolled as the control group. Patients in both the anastomosis group and the control group were followed up for 5 years, and the incidences of cerebral hemorrhage and cerebral ischemia were analyzed. Blood samples were collected in both groups before and after treatment. Mononuclear cells were separated by density gradient centrifugation. After labeling with 3 direct fluorescent antibodies (CD133, CD34, and vascular endothelial growth factor receptor 2), the number of endothelial progenitor cells (EPCs) was detected using flow cytometry. Cerebral blood flow was remarkably improved after STA-MCA anastomosis. The incidences of cerebral hemorrhage and cerebral ischemia were significantly lower in the anastomosis group than in the control group. The number of EPCs showed no significant change before and after treatment in the control group; in contrast, it was decreased significantly after surgery in the anastomosis group. STA-MCA anastomosis can reduce the number of EPCs in MMD patients, lower the risk of rebreeding, and improve cerebral ischemic attacks.

Quantitative cerebral perfusion assessment using microscope-integrated analysis of intraoperative indocyanine green fluorescence angiography versus positron emission tomography in superficial temporal artery to middle cerebral artery anastomosis.

Background:Intraoperative qualitative indocyanine green (ICG) angiography has been used in cerebrovascular surgery. Hyperperfusion may lead to neurological complications after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis. The purpose of this study is to quantitatively evaluate intraoperative cerebral perfusion using microscope-integrated dynamic ICG fluorescence analysis, and to assess whether this value predicts hyperperfusion syndrome (HPS) after STA-MCA anastomosis.Methods:Ten patients undergoing STA-MCA anastomosis due to unilateral major cerebral artery occlusive disease were included. Ten patients with normal cerebral perfusion served as controls. The ICG transit curve from six regions of interest (ROIs) on the cortex, corresponding to ROIs on positron emission tomography (PET) study, was recorded. Maximum intensity (IMAX), cerebral blood flow index (CBFi), rise time (RT), and time to peak (TTP) were evaluated.Results:RT/TTP, but not IMAX or CBFi, could differentiate between control and study subjects. RT/TTP correlated (|r| = 0.534-0.807; P < 0.01) with mean transit time (MTT)/MTT ratio in the ipsilateral to contralateral hemisphere by PET study. Bland–Altman analysis showed a wide limit of agreement between RT and MTT and between TTP and MTT. The ratio of RT before and after bypass procedures was significantly lower in patients with postoperative HPS than in patients without postoperative HPS (0.60 ± 0.032 and 0.80 ± 0.056, respectively; P = 0.017). The ratio of TTP was also significantly lower in patients with postoperative HPS than in patients without postoperative HPS (0.64 ± 0.081 and 0.85 ± 0.095, respectively; P = 0.017).Conclusions:Time-dependent intraoperative parameters from the ICG transit curve provide quantitative information regarding cerebral circulation time with quality and utility comparable to information obtained by PET. These parameters may help predict the occurrence of postoperative HPS.

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.

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.

Transient Crossed Cerebellar Diaschisis Due to Cerebral Hyperperfusion Following Surgical Revascularization for Moyamoya Disease

Crossed cerebellar diaschisis (CCD) often occurs after ischemic or hemorrhagic stroke that damages the cortico-ponto-cerebellar pathway. However, CCD due to cerebral hyperperfusion following cerebrovascular reconstruction is rare. A 61-year-old woman presented with transient CCD due to cerebral hyperperfusion following bypass surgery for adult moyamoya disease. She developed transient weakness of the right extremities and was diagnosed with moyamoya disease. First, she underwent superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis with indirect synangiosis on the left. Postoperative course was uneventful. Subsequently, she underwent STA-MCA anastomosis with indirect synangiosis on the right. She complained of mild headache on the right, and single photon emission computed tomography (SPECT) performed on the 7th postoperative day demonstrated hyperperfusion in the right frontal and temporal lobes associated with hypoperfusion in the left cerebellum. Magnetic resonance (MR) imaging demonstrated no new lesions and MR angiography showed patent STA-MCA bypass. Subsequent SPECT showed disappearance of both hyperperfusion and CCD. This case strongly suggests that cerebral hyperperfusion after bypass surgery for moyamoya disease may cause transient CCD. Although the clinical significance is still obscure, this phenomenon indicates the cortico-ponto-cerebellar pathway is interrupted due to hyperperfusion, suggesting the development of hyperperfusion syndrome. Careful observation of cerebral hemodynamics after bypass surgery is warranted to avoid hyperperfusion-related complications.

Incidence and Pathogenesis of Transient Cheiro-Oral Syndrome After Surgical Revascularization for Moyamoya Disease

There are no reports that denote transient cheiro-oral syndrome (COS) after surgical revascularization for moyamoya disease. To clarify the incidence and pathogenesis of transient COS after surgical revascularization for moyamoya disease. This study included 21 patients who underwent superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis and indirect bypass because of Moyamoya disease. Their medical records were evaluated to identify clinical features of postoperative transient COS. The findings on MRI, magnetic resonance angiography, and single-photon emission computed tomography were also analyzed. Transient COS developed in 8 (22.9%) of 35 operated hemispheres, or in 6 (28.6%) of 21 patients between 3 and 20 days after surgery. Most of the COS were associated with mild weakness of the ipsilateral face and hand. Simultaneous radiological studies detected no findings of cerebral infarct or postoperative hyperperfusion. STA-MCA anastomosis was patent in all patients. However, their disease stage more frequently progressed owing to considerable blood flow via STA-MCA anastomosis, and basal moyamoya vessels disappeared or diminished in patients with transient COS rather than in those without. Transient COS after surgical revascularization for moyamoya disease is not rare. Bypass flow through STA-MCA anastomosis may stimulate a rapid progression of disease stage and diminish basal moyamoya vessels, causing transient COS within 3 weeks after surgery.

Novel Bypass Surgery for Moyamoya Disease Using Pericranial Flap

We reviewed our 11-year experience with a novel bypass procedure, superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis and encephalo-duro-myo-arterio-pericranio-synangiosis (EDMAPS), for moyamoya disease regarding cerebral hemodynamics and long-term outcome. This prospective study included 75 patients with moyamoya disease, including 28 children and 47 adults. We performed STA-MCA anastomosis and EDMAPS on 123 hemispheres of 75 patients. In addition to conventional STA-MCA anastomosis and indirect bypass for the MCA territory, the medial frontal lobe was revascularized using the frontal pericranial flap through medial frontal craniotomy. Surgical results were analyzed with magnetic resonance imaging, cerebral angiography, and single-photon emission computed tomography/positron emission tomography. Overall incidences of mortality and morbidity were 0% and 5.7%, respectively. The annual risk of cerebrovascular events during the follow-up periods was very low: 0% in pediatric patients and 0.4% in adults over approximately 67 months. Postoperative cerebral angiography showed that the pericranial flap functioned well as donor tissue for indirect bypass, especially in pediatric patients. Follow-up single-photon emission computed tomography/positron emission tomography studies revealed that cerebral blood flow and its reactivity to acetazolamide markedly improved in both the MCA and anterior cerebral artery territories. These findings strongly suggest that STA-MCA anastomosis and EDMAPS using a frontal pericranial flap is a safe and effective surgical procedure to further improve the long-term prognosis in moyamoya disease by improving cerebral hemodynamics in both the MCA and anterior cerebral artery territories.

Pure Vasogenic Edema Caused by Cerebral Hyperperfusion After Superficial Temporal Artery to Middle Cerebral Artery Anastomosis -Case Report-

A 63-year-old patient presented with cerebral hyperperfusion manifesting as transient aphasia and general tonic convulsions 3 and 4 days after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis. Diffusion-weighted magnetic resonance (MR) imaging revealed a focal low-intensity area at the site of anastomosis in the left temporal lobe, with high apparent diffusion coefficient, together with focal intense increase in cerebral blood flow in the same region. This lesion was considered to be pure vasogenic edema caused by cerebral hyperperfusion. Additional treatment with intravenous drip infusion of free radical scavenger and reduction in blood pressure with nicardipine improved the patient's symptoms and brain edema. The brain edema gradually decreased on MR imaging and completely disappeared at 3 months after bypass surgery. Cerebral hyperperfusion is often encountered after recanalization of occlusive arteries, removal of arteriovenous malformations, and carotid endarterectomy, but may also occur after STA-MCA anastomosis.

Minimally invasive superficial temporal artery to middle cerebral artery bypass through a minicraniotomy: benefit of three-dimensional virtual reality planning using magnetic resonance angiography

The aim of the authors in this study was to introduce a minimally invasive superficial temporal artery to middle cerebral artery (STA-MCA) bypass surgery by the preselection of appropriate donor and recipient branches in a 3D virtual reality setting based on 3-T MR angiography data. An STA-MCA anastomosis was performed in each of 5 patients. Before surgery, 3-T MR imaging was performed with 3D magnetization-prepared rapid acquisition gradient echo sequences, and a high-resolution CT 3D dataset was obtained. Image fusion and the construction of a 3D virtual reality model of each patient were completed. In the 3D virtual reality setting, the skin surface, skull surface, and extra- and intracranial arteries as well as the cortical brain surface could be displayed in detail. The surgical approach was successfully visualized in virtual reality. The anatomical relationship of structures of interest could be evaluated based on different values of translucency in all cases. The closest point of the appropriate donor branch of the STA and the most suitable recipient M(3) or M(4) segment could be calculated with high accuracy preoperatively and determined as the center point of the following minicraniotomy. Localization of the craniotomy and the skin incision on top of the STA branch was calculated with the system, and these data were transferred onto the patient's skin before surgery. In all cases the preselected arteries could be found intraoperatively in exact agreement with the preoperative planning data. Successful extracranial-intracranial bypass surgery was achieved without stereotactic neuronavigation via a preselected minimally invasive approach in all cases. Subsequent enlargement of the craniotomy was not necessary. Perioperative complications were not observed. All bypasses remained patent on follow-up. With the application of a 3D virtual reality planning system, the extent of skin incision and tissue trauma as well as the size of the bone flap was minimal. The closest point of the appropriate donor branch of the STA and the most suitable recipient M(3) or M(4) segment could be preoperatively determined with high accuracy so that the STA-MCA bypass could be safely and effectively performed through an optimally located minicraniotomy with a mean diameter of 22 mm without the need for stereotactic guidance.

External Carotid Artery Angioplasty and Stenting Followed by Superficial Temporal Artery to Middle Cerebral Artery Anastomosis

A 31-year-old man presented with right hemiparesis, and magnetic resonance imaging revealed a small infarct at left basal ganglia. Digital subtraction angiography showed left cervical internal carotid artery (ICA) occlusion and severe stenosis of the ipsilateral external carotid artery (ECA) with collateral cerebral circulation fed by ECAs. Based on the results of a functional evaluation of cerebral blood flow, we performed preventive ECA angioplasty and stenting for advanced ECA stenosis to ensure sufficient blood flow to the superficial temporal artery. Eight weeks later, superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis was performed. His postoperative course was uneventful and no additional transient ischemic attacks have occurred. To our knowledge, this is the first report of preventive angioplasty and stenting for advanced narrowing of an ECA before STA-MCA anastomosis for ipsilateral ICA occlusion.

Development of Brain Infarction after Extracranial-Intracranial Bypass Surgery in a Patient with Moyamoya Disease: A case report

Moyamoya disease is characterized by a narrowing or occlusion of both internal carotid arteries in the presence of an abnormal hemangiomatosis vascular network at the base of the brain. These patients increasingly present for surgical management to improve the cerebral circulation. However, surgery may be complicated by cerebral ischemia, and thus patients require particular care during the perioperative period. The risk factors of perioperative ischemic complications include the presence of a preoperative low density area by computed tomography, the occurrence of frequent preoperative transient ischemic attacks, or hypocapnia or hypotension. We describe one case of general anesthesia for superficial temporal artery to middle cerebral artery anastomosis (STA-MCA) with encephalomyosynangiosis (EMS) in a moyamoya disease patient. The patient expired because of a developing cerebral infarction on the fifth postoperative day.

Efficacy of direct revascularization in adult Moyamoya disease: haemodynamic evaluation by positron emission tomography.

To evaluate the efficacy of direct cerebrovascular reconstruction to prevent intracranial bleeding from the point of view of haemodynamic status, we performed positron emission tomography (PET) studies in 5 adult patients with Moyamoya disease before and after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis. Regional cerebral blood flow (rCBF), regional cerebral metabolic rate of oxygen (rCMRO2) and regional oxygen extraction fraction (rOEF) in the MCA territories and regional cerebral blood volume (rCBV) in the striatum were measured before and after STA-MCA anastomosis. Correlation between the change of these PET parameters and post-operative decreased opacification of Moyamoya vessels were analyzed. Pre-operatively, significant elevation of rCBV were observed in the basal ganglia as well as significant reduction of rCBF and elevation of rOEF with reduction of rCMRO2 in the MCA territories, indicating "misery" perfusion in the cerebral hemisphere and blood pooling in the Moyamoya vessels under increased haemodynamic stress. Post-operative PET study showed improvement of misery perfusion and reduction of rCBV in the basal ganglia. Reduction of rCBV in the basal ganglia generally compatible with decreasing Moyamoya vessels on angiographic findings. Our results suggests that direct bypass surgery could have a potential both for decreasing haemodynamic stress on Moyamoya vessels and to improve misery perfusion in the hemisphere.