A case of adult moyamoya disease progressed after vascular reconstructive surgery

We report an adult onset patient with moyamoya disease showing acute progress after contralateral vascular reconstructive surgery. A 47-year-old female developed cerebral infarction in the left corona radiata. A magnetic resonance (MR) angiography and a cerebral angiogram revealed severe stenosis extending from the terminal portion of left internal carotid artery (ICA) to the M1 portion. The right ICA showed slight stenosis. We performed direct bypass surgery (STA-MCA anastomosis) on the affected left side. MR angiography 1 month after surgery revealed the progressive stenosis of the C1 portion of the right ICA. While measurement of cerebral blood flow (CBF) showed a slight impairment of vascular reactivity to acetazolamide loading in the region of the right MCA, we continued without vascular reconstructive surgery for the right side because there was no ischemic attack. The patient had a transient sensory disturbance of the left upper extremity 16 months after surgery. MR angiography and a cerebral angiogram revealed more progressive stenosis extending from the right ICA to the M1 portion. CBF study showed a low CBF at rest and a negative response to acetazolamide loading in the region of the right MCA. Direct bypass surgery was performed on the right hemisphere. Follow-up study revealed an increment of rest CBF and improvement of vascular reactivity. We underlined the necessity for careful postoperation observation of progressive contralateral arterial stenosis using MR angiography and CBF study in adult onset patients with moyamoya disease.     

Simultaneous superficial temporal artery to middle cerebral or anterior cerebral artery bypass with pan-synangiosis for Moyamoya disease covering both anterior and middle cerebral artery territories

Some patients with moyamoya disease treated by conventional surgical procedures may develop postoperative refractory ischemia and perioperative cerebral infarction in the anterior cerebral artery (ACA) territory. We present a novel operative procedure for moyamoya disease to avoid the risk of ischemia in the ACA territory, which consists of simultaneous superficial temporal artery (STA) to middle cerebral artery (MCA) or ACA bypass with pan-synangiosis, encephalo-duro-arterio-myo-synangiosis for the lateral frontal and temporal areas, and encephalo-galeo-arterio-synangiosis for the medial frontal area. This procedure can establish direct bypass to the ACA territory at the first intervention. Simultaneous STA-MCA and STA-ACA bypasses with pan-synangiosis is suitable for patients with moyamoya disease associated with severely impaired perfusion of the ACA territory requiring direct bypass surgery.     

Transient crossed cerebellar diaschisis due to cerebral hyperperfusion following surgical revascularization for moyamoya disease: case report

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.     

Venous Reddening as a Possible Sign of Hyperperfusion after Superficial Temporal Artery-Middle Cerebral Artery Anastomosis for Moyamoya Disease: Case Report

Here we report a case of moyamoya disease in which cortical veins reddened after superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis, following postoperative hyperperfusion. A 37-year-old man with moyamoya disease suffered cerebral infarction in his right hemisphere. Single photon emission computed tomography (SPECT) showed impaired cerebral blood flow (CBF) in both cerebral hemispheres. The patient underwent STA-MCA anastomosis in the right cerebral hemisphere. During operation, soon after declamping the STA, cortical veins near the anastomosis site changed its color from blue to red. This change was repeatable by clamping and declamping of the STA. Postoperative SPECT and computed tomography (CT) demonstrated increased CBF and subarachnoid hemorrhage at the anastomosis site, suggesting the occurrence of postoperative hyperperfusion. By strictly controlling the patient''s blood pressure, the syndrome resolved 1 week after the operation. We propose that the venous reddening after STA-MCA anastomosis may be a sign of postoperative hyperperfusion.     

A ruptured middle cerebral artery aneurysm originating from the site of anastomosis 20 years after extracranial-intracranial bypass for moyamoya disease: case report

BACKGROUND: Direct revascularization through a superficial temporal artery-middle cerebral artery (STA-MCA) bypass is often performed to prevent ischemic or hemorrhagic attack in patients with moyamoya disease. This is the first reported case of aneurysm formation and rupture due to an STA-MCA bypass in a patient with moyamoya disease. CASE DESCRIPTION: A 52-year-old man who had undergone bilateral STA-MCA bypass for caudate hemorrhage due to moyamoya disease 20 years previously suffered from sudden-onset unconsciousness. Computed tomography revealed a massive intracerebral hematoma (ICH) in the left frontoparietal region. Angiography showed good patency of the anastomoses and stage IV moyamoya disease. However, no other abnormality was found. Emergency evacuation of the hematoma was performed. The patient's postoperative course was uneventful, but consciousness disturbance of sudden onset occurred 1 month later. Computed tomography showed a hematoma in the lateral ventricle and acute hydrocephalus. Repeat angiography revealed an aneurysm on the left side of the anastomosis. Bilateral ventricle drainage tubes were inserted, and the aneurysm was clipped. A ventriculoperitoneal shunt was later performed. CONCLUSION: In patients with moyamoya disease who have undergone extracranial-intracranial bypass surgery, progressive hemodynamic stress may cause the formation of de novo aneurysms after a postoperative period of several decades. Imaging examinations should therefore be performed periodically for follow-up, and a de novo aneurysm should be suspected in a patient who has an unusual ICH.     

Temporal change of 3-T magnetic resonance imaging/angiography during symptomatic cerebral hyperperfusion following superficial temporal artery-middle cerebral artery anastomosis in a patient with adult-onset moyamoya disease

Superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis is a safe and effective treatment for moyamoya disease, although recent evidence suggests its substantial risk for symptomatic cerebral hyperperfusion. The diagnostic value of single-photon emission computed tomography (SPECT) for postoperative hyperperfusion in moyamoya patients is well established, but that of magnetic resonance (MR) imaging/angiography is undetermined. A 22-year-old woman with hemorrhagic-onset moyamoya disease underwent STA-MCA anastomosis on the right hemisphere, but she suffered from transient left hemiparesis and facial paresis owing to cerebral hyperperfusion from 3 to 11 days after surgery as delineated by SPECT. The time-sequential 3-T MR angiography revealed intense high signal of donor STA and dilated branches of MCA around the site of the anastomosis. These findings were most prominent at 8 days after surgery, when her neurologic signs were most apparent. Intensive blood pressure control relieved her symptom and she was discharged without neurologic deficit. MR findings normalized 3 months later. The characteristic findings of 3-T MR angiography, which was not evident by 1.5-T MR angiography in the previous studies, may reflect intrinsic pathology of postoperative cerebral hyperperfusion. It could be a useful diagnostic tool after revascularization surgery for moyamoya disease.     

Temporal change of 3-T magnetic resonance imaging/angiography during symptomatic cerebral hyperperfusion following superficial temporal artery–middle cerebral artery anastomosis in a patient with adult-onset moyamoya disease

Superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis is a safe and effective treatment for moyamoya disease, although recent evidence suggests its substantial risk for symptomatic cerebral hyperperfusion. The diagnostic value of single-photon emission computed tomography (SPECT) for postoperative hyperperfusion in moyamoya patients is well established, but that of magnetic resonance (MR) imaging/angiography is undetermined. A 22-year-old woman with hemorrhagic-onset moyamoya disease underwent STA-MCA anastomosis on the right hemisphere, but she suffered from transient left hemiparesis and facial paresis owing to cerebral hyperperfusion from 3 to 11 days after surgery as delineated by SPECT. The time-sequential 3-T MR angiography revealed intense high signal of donor STA and dilated branches of MCA around the site of the anastomosis. These findings were most prominent at 8 days after surgery, when her neurologic signs were most apparent. Intensive blood pressure control relieved her symptom and she was discharged without neurologic deficit. MR findings normalized 3 months later. The characteristic findings of 3-T MR angiography, which was not evident by 1.5-T MR angiography in the previous studies, may reflect intrinsic pathology of postoperative cerebral hyperperfusion. It could be a useful diagnostic tool after revascularization surgery for moyamoya disease.     

Progression of arteriovenous malformation in moyamoya syndrome

Summary We report a case of moyamoya disease (MMD) associated with arteriovenous malformation (AVM). The 30-year-old female patient presented with left-hemispheric transient ischaemic attacks (TIAs) involving dysphasia and right-sided hemiparesis. CT-scan and lumbar puncture showed no evidence of intracranial haemorrhage. Cerebral angiography revealed typical moyamoya vessels and occlusion of multiple cerebral arteries with consecutive collateral blood supply. Moreover, a left-parietal AVM with a diameter of approximately 2 cm was detected. An extra-intracranial arterial bypass (EIAB) connecting the left superficial temporal artery (STA) with a cortical branch of the left middle cerebral artery (MCA) was performed (STA-MCA anastomosis) and yielded subsequent resolution of the neurological deficit. Nine months post-operatively neurological deficits similar to those of the initial presentation recurred. Repeated angiography suggested comparatively increased AVM blood flow, and successful extirpation of the AVM gradually re-established almost full functional ability. However, deterioration of the neurological condition developed again. We herewith present the first European case of moyamoya disease associated with arteriovenous malformation and report the clinical course under an alternative neurosurgical treatment consisting of STA-MCA anastomosis and delayed extirpation of the AVM.     

Focal hyperperfusion after superficial temporal artery-middle cerebral artery anastomosis in a patient with moyamoya disease. Case report

Superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis is a standard surgical therapeutic option in patients with moyamoya disease. Most patients experience improvement in their clinical symptoms immediately after surgery. The authors report on the case of a 39-year-old man with moyamoya disease who suffered from temporary and frequent neurological deterioration after undergoing a left STA-MCA anastomosis. Hemodilution and hypervolemia therapies did not improve his course. Technetium-99m hexamethylpropyleneamine oxime single-photon emission tomography scans demonstrated focal intense accumulation of the tracer in the frontal operculum on the side of the surgery. Although diffusion-weighted magnetic resonance (MR) imaging demonstrated no abnormalities except for the postoperative change, perfusion-weighted MR images and MR digital subtraction angiography revealed focal hyperperfusion in the left frontal operculum where the cerebral perfusion reserve was severely disturbed preoperatively. This evidence strongly supports the notion that focal hyperperfusion observed after STA-MCA anastomosis could occur in the poor perfusion reserve area preoperatively and could cause temporary neurological deterioration.     

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

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.     

Changes in Computed Tomography Perfusion Parameters after Superficial Temporal Artery to Middle Cerebral Artery Bypass: An Analysis of 29 Cases

Introduction Analysis of computed tomography perfusion (CTP) studies before and after superficial temporal artery to middle cerebral artery (STA-MCA) bypass is warranted to better understand cerebral steno-occlusive pathology. Methods Retrospective review was performed of STA-MCA bypass patients with steno-occlusive disease with CTP before and after surgery. CTP parameters were evaluated for change after STA-MCA bypass. Results A total of 29 hemispheres were bypassed in 23 patients. After STA-MCA bypass, mean transit time (MTT) and time to peak (TTP) improved. When analyzed as a ratio to the contralateral hemisphere, MTT, TTP, and cerebral blood flow (CBF) improved. There was no effect of gender, double vessel versus single vessel bypass, or time until postoperative CTP study to changes in CTP parameters after bypass. Conclusions Blood flow augmentation after STA-MCA bypass may best be assessed by CTP using baseline MTT or TTP and ratios of MTT, TTP, or CBF to the contralateral hemisphere. The failure of cerebrovascular reserve to improve after cerebral bypass may indicate irreversible loss of autoregulation with chronic cerebral vasodilation or the inability of CTP to detect these improvements.     

Effect of direct arterial bypass on the prevention of future stroke in patients with the hemorrhagic variety of moyamoya disease

OBJECT: The authors evaluated the effects of superficial temporal artery-middle cerebral artery (STA-MCA) bypass in the prevention of future stroke, including rebleeding or an ischemic event, in patients suffering from hemorrhagic moyamoya disease by comparing this method with indirect bypass and conservative treatment. METHODS: Twenty-two patients who had hemorrhagic moyamoya disease but no aneurysm comprised the study group. These patients' clinical charts were examined with respect to their treatment and clinical course after an initial hemorrhagic episode. The mean age of the patients was 43 years and the follow-up period ranged from 0.8 to 15.1 years, with a mean of 8 years. Eleven patients (50%) were conservatively treated. Among the 11 patients who were surgically treated, STA-MCA bypass was performed in six patients (27%) and encephaloduroarteriosynangiosis (EDAS) in the other five patients (23%). Nine patients (41%) presented with an ischemic or rebleeding event during the follow-up period. The incidence of future stroke events in patients who had undergone an STA-MCA bypass was significantly lower (p<0.05) than that in patients who had been treated conservatively or with EDAS. Kaplan-Meier plots comparing stroke-free times in patients treated with direct bypass and those in patients who conservatively or with indirect bypass showed a significant difference (p<0.05) in favor of direct bypass. CONCLUSIONS: The effect of STA-MCA bypass on the prevention of recurrent hemorrhage or an ischemic event in patients with hemorrhagic moyamoya disease has been statistically confirmed in this study.     

History of the development of surgical treatments for moyamoya disease

Many surgical treatments for moyamoya disease have been developed over the past 40 years. The optimum treatment for ischemic-type moyamoya disease is almost established. The first surgical treatment for the disease was the superficial temporal artery to middle carotid artery (STA-MCA) anastomosis. The discovery of spontaneous collateral formation following the STA-MCA anastomosis surgery led to the development of various indirect bypass procedures. Collateral formation and clinical outcomes from direct and indirect procedures have been compared to assess the merits and limitations of each technique. Experience and a greater understanding of the surgical effects of moyamoya disease have led to the development of surgical procedures combining various direct and indirect bypass techniques for optimal restoration of perfusion. This review of the historical development and efficacy of each procedure will aid surgeons in selecting the most appropriate surgical procedure for patients of different ages with different symptoms and disease severities.     

Asymptomatic intracerebral hemorrhage under strict blood pressure control due to postoperative cerebral hyperperfusion in a patient with moyamoya disease

We report a case of moyamoya disease manifesting as asymptomatic intracerebral hemorrhage due to postoperative cerebral hyperperfusion, despite the prophylactic intensive blood pressure control. This 35-year-old man initially suffered from right upper quadrantanopsia and was found to have cerebral infarction in the left occipital lobe due to moyamoya disease. He also manifested preoperatively a small intracerebral hemorrhage at the left caudate nucleus. The left cerebral hemisphere showed apparent hemodynamic compromise, thus he underwent left superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis with indirect pial synangiosis. He was subjected to prophylactic strict blood pressure control postoperatively to avoid hyperperfusion syndrome. The N-isopropyl-p-¹²³I-Iodoamphetamine SPECT (¹²³I-IMP-SPECT) 1 day after surgery showed intense increase in cerebral blood flow (CBF) at the site of the anastomosis, and further blood pressure lowering was attempted. He did not suffer from neurologic deterioration during the postoperative period, while computed tomography (CT) 7 days after surgery revealed asymptomatic intracerebral hematoma (ICH) at the subcortex under the site of the anastomosis. Cerebral hyperperfusion is a potential complication of revascularization surgery for moyamoya disease. Accurate diagnosis and proper management of hyperperfusion are essential to avoid deleterious neurologic event due to hyperperfusion.     

Two cases of main trunk artery occlusion associated with multiple cerebral aneurysms

We report 2 cases of multiple aneurysms (AN) associated with main trunk artery occlusion. CASE 1: A 52-year-old male was admitted to our hospital with dysarthria and weakness of the right side of the body. Computed tomography (CT) showed cerebral infarction in the left corona radiata. MR angiography and conventional angiography showed occlusion of the left middle cerebral artery (MCA) and saccular aneurysms (ANs) at the origin of the anterior communicating artery (A-com) and bifurcation of the right MCA. Subsequent 123I-IMP-single photon emission tomography (SPECT) revealed marked reduction of cerebral blood flow and disturbed reactivity to acetazolamide in the left cerebral hemisphere. Superficial temporal artery (STA)-MCA anastomosis was performed to improve cerebral blood flow and reduce hemodynamic stress for AN of the A-com and right MCA. At 5 months after the first operation, neck clipping was performed successfully for the non-ruptured A-com AN and right MCA AN. CASE 2: A 65-year-old male was admitted to our hospital. CT revealed subarachnoid hemorrhage (SAH), and 3D-computed tomographic angiography (CTA) and cerebral angiography showed basilar top AN, A-com AN and right MCA AN associated with right internal carotid artery occlusion. Right ACA and MCA territories were visualized from the A-com artery and posterior cerebral artery. STA-MCA anastomosis was performed to improve cerebral blood flow and reduce hemodynamic stress for ANs. In the same operation, successful neck clipping was performed for BA top AN and right MCA AN. In such cases as these, particularly in ischemic cases associated with main trunk artery occlusion, it was important to consider surgery for AN after STA-MCA anastomosis in anticipation of improved cerebral blood flow and reduce hemodynamic stress for AN.     

Efficacy of superficial temporal artery-middle cerebral artery double bypass in patients with hemorrhagic moyamoya disease: surgical effects for operated hemispheric sides

Neurosurgical Review - The effects of superficial temporal artery to middle cerebral artery (STA-MCA) double bypass on recurrent hemorrhage in the operated hemisphere in hemorrhagic moyamoya...     

Efficacy of Direct Revascularization in Adult Moyamoya Disease: Haemodynamic Evaluation by Positron Emission Tomography

Summary  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.     

Ischemic stroke due to dissection of the middle cerebral artery treated by superficial temporal artery-middle cerebral artery anastomosis--case report

A 62-year-old man presented with dissection of the right middle cerebral artery (MCA) manifesting as mild headache, right hemiparesis, and slurred speech. Magnetic resonance (MR) imaging and MR angiography revealed fresh infarction in the right basal ganglia, and severe stenosis and dilatation of the right MCA. Digital subtraction angiography approximately 24 hours after admission revealed a linear contrast defect indicating an intimal flap of the M(1) segment. The diagnosis was dissection of the MCA. His neurological deficits improved gradually. Although he was neurologically stable, diffusion-weighted MR imaging revealed enlarging infarct size over the right MCA territory, and the right M(1) segment had progressive stenosis. Superficial temporal artery (STA)-MCA anastomosis was performed on the 26th day. Follow-up angiography showed good patency of the STA-MCA anastomosis, repair of the dissection of the M(1) segment, and improvement of the flow in the MCA. The patient was discharged from our hospital with no neurological deficits. Although the dissection in this case was spontaneously repaired, STA-MCA anastomosis was useful to get through a critical time. If the stenosis shows further progression or the infarction size enlarges, STA-MCA anastomosis may be effective.