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.     

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.     

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 Anastomoses in a Patient with Rapidly Progressive Moyamoya Disease: Case Report

Moyamoya disease can be associated with a rapidly progressive course in young patients. This report describes a patient with moyamoya disease who experienced rapid disease progression, resulting in cerebral infarction and a wide area of diminished cerebral perfusion. Double superficial temporal artery (STA)-middle cerebral artery (MCA) anastomoses were utilized to immediately increase cerebral perfusion in the affected area. This case involved a 5-year-old girl who had been diagnosed with moyamoya disease and had undergone STA-MCA anastomosis with indirect bypass in the right hemisphere at the age of 3. At the time of presentation, magnetic resonance (MR) imaging showed cerebral infarction at the left frontal lobe, and MR angiography showed rapidly progressive narrowing of the left MCA that had not been present 3 months prior. N-isopropyl-p-[I123] iodoamphetamine single-photon emission computed tomography (IMP-SPECT) showed markedly decreased uptake in the left hemisphere. She underwent emergent STA-MCA double anastomoses with indirect bypass on the left side. IMP-SPECT showed marked increase in uptake in the left hemisphere. The anterior cerebral artery (ACA) territory adjacent to the cerebral infarction also showed increased uptake on the SPECT. Postoperatively, there were no clinical or radiographic indications of ischemic or hemorrhagic complications. Double anastomoses are effective in quickly and significantly increasing blood flow. The postoperative course in this case was uneventful. Double anastomoses are a surgical option for patients with moyamoya disease who show rapid disease progression, even in those in the acute phase of cerebral infarction.     

Thrombosed unruptured cerebral aneurysm causing brain infarction followed by subarachnoid hemorrhage--case report--

A 71-year-old man presented with right hemiparesis and aphasia due to cerebral infarction in the frontal lobe. Computed tomography (CT) revealed a high-density mass, 12 mm in diameter, in the stem of the left sylvian fissure. Carotid angiography demonstrated occlusion of the left ascending frontal artery complex and retention of contrast medium at the bifurcation of the left middle cerebral artery (MCA). The diagnosis was cerebral infarction caused by occlusion of the ascending frontal artery complex resulting from thrombosed left MCA aneurysm. The patient was managed conservatively and his neurological symptoms gradually improved. One month later, he lapsed into a coma. CT revealed subarachnoid hemorrhage. Carotid angiography showed a large left MCA aneurysm with branch occlusion of the left ascending frontal artery complex. A left frontotemporal craniotomy was performed. The MCA aneurysm was opened and the intramural thrombi removed, and finally neck clipping was performed. The patient made a good postoperative recovery.     

Interhemispheric intracranial pressure gradients in massive cerebral infarction

We report continuous bilateral intracranial pressure (ICP) monitoring immediately after transtentorial herniation in a patient with massive cerebral infarction to: 1) determine presence and time course of compartmental ICP differences, and 2) to study effects of therapy on both hemispheres. A 55-year-old man admitted with watershed infarctions in the left anterior-middle-posterior cerebral arteries distribution. Initial investigations demonstrated highly narrowed left extracranial internal carotid artery. Eight days later he developed unexplained lethargy and anisocoria. Head computerized tomography (CT) showed massive left hemispheric infarction, edema, and midline shift. Bilateral subarachnoid bolts demonstrated equally elevated ICP in both hemispheres. Hyperventilation and osmotic therapy produced near-identical ICP reduction bilaterally with resolution of anisocoria. Later, plateau waves and autonomic instability developed. Shortly before loss of brainstem function, interhemispheric ICP gradients (left greater than right) of 30-40 mm Hg developed. Intracranial pressure did not equalize prior to brain death determination. Bilateral ICP monitoring did not reveal an interhemispheric ICP gradient soon after transtentorial herniation in massive MCA infarction. The presence of interhemispheric ICP gradients in massive stroke remains unproven and further clinical study is necessary.     

Intracerebral hemorrhage from a ruptured pseudoaneurysm after STA-MCA anastomosis--case report

A 43-year-old hypertensive male developed a pseudoaneurysm at the site of a superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis, causing massive intracerebral hemorrhage 5 years after the operation. He first experienced repeated transient ischemic attacks, and cerebral angiography disclosed complete occlusion in the cervical portion of the left internal carotid artery. STA-MCA anastomosis was performed, and the ischemic attacks stopped. Postoperative angiography confirmed patency of the anastomosis and good filling of the cortical branches of the left MCA. Five years after surgery, the patient suffered sudden onset of generalized convulsions and consciousness disturbance. Computed tomography disclosed a massive intracerebral hemorrhage in the left frontoparietal region, and angiography revealed an aneurysmal dilatation at the site of the anastomosis that was not seen before. Emergency evacuation of the hematoma and clipping of the aneurysmal dilatation were performed. The patient recovered well and became ambulatory. Histological examination of the surgical specimen showed collagen tissue, indicating a pseudoaneurysm. Patients who undergo STA-MCA anastomosis, especially hypertensive patients, should be followed up by repeated magnetic resonance angiography to confirm the patency of the anastomosis and cerebral perfusion, and to detect the formation of pseudoaneurysms at the anastomosis site, which can cause fatal bleeding.     

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.     

Cerebral infarction along the distribution of perforating arteries during aneurysm surgery in a patient with pheochromocytoma--case report

A 58-year-old woman with refractory hypertension presented with subarachnoid hemorrhage. Digital subtraction angiography and three-dimensional computed tomography (CT) angiography revealed a ruptured left vertebral artery (VA) aneurysm and an unruptured left middle cerebral artery (MCA) aneurysm. The patient successfully underwent neck clipping of the left VA aneurysm. However, CT obtained just after the operation showed an asymptomatic cerebral infarction along the distribution of medial striate arteries of the right anterior cerebral artery in the caudate nucleus. The pathogenesis of the infarction was unknown. Before clipping surgery of the left MCA aneurysm, detailed examinations to find the cause of her refractory hypertension were performed. Laboratory tests revealed plasma serum level of norepinephrine at 15,521 pg/ml (normal range 100-450 pg/ml). Abdominal magnetic resonance imaging revealed a pheochromocytoma in the right adrenal gland. After preoperative management of the pheochromocytoma, the neck of the left MCA aneurysm was successfully clipped. When the patient awakened from anesthesia, she noticed right hemiparesis and motor aphasia. CT showed cerebral infarction along the distribution of lenticulostriate arteries of the left MCA in the putamen. Her symptoms gradually improved, and the pheochromocytoma was removed by laparoscopic surgery. Sustained severe hypertension and depletion of blood volume resulting from excess catecholamine release from the pheochromocytoma may have caused the complications. Hypervolemic fluid infusion and maintenance of normotensive blood pressure during surgery may avoid such ischemic events.     

A case of non-traumatic direct carotid-cavernous fistula presenting with cerebral infarction

A 76-year-old female presented with a rare case of cerebral infarction as a complication of non-traumatic direct carotid-cavernous fistula (CCF). She had left hemiparesis and magnetic resonance imaging revealed cerebral infarction in the right watershed area. Angiography showed a right high-flow direct CCF with total blood steal. Preoperative 123I-IMP SPECT revealed a hypoperfusion area in the region of the right anterior cerebral artery and right middle cerebral artery. In addition, she had double vision caused by abducens nerve palsy. Transarterial embolization of the fistula with endovascular trapping using detachable coils achieved complete obliteration of the right internal carotid artery and adequate flow reduction of the direct CCF. Postoperative angiography showed good filling of the collateral-flow via the posterior communicating artery without retrograde blood steal to the CCF. Her symptoms improved gradually after the procedure. Diffusion-weighted MR imaging obtained 8 days after the procedure revealed a few high signals in the right hemisphere, suggesting cerebral infarctions, but she presented no symptom. Postoperative 123 I-IMP SPECT showed an improvement of cerebral perfusion in the region of the right MCA posterior and left MCA. Cerebral ischemia caused by direct CCF is rare, and there are only a few reports of non-traumatic direct CCF presenting with cerebral infarction. This very rare case suggests that endovascular trapping is safe and useful as a treatment for direct CCF, especially in the case of an elderly patient with total blood steal.     

Cerebral artery occlusion due to blunt cervical trauma

Three cases are reported in which cerebral infarction developed due to blunt cervical trauma. All of these patients had external signs of cervical trauma and presented focal cerebral ischemic symptoms. Cerebral angiography demonstrated characteristic findings in each case. The first case: A 27 year-old man developed left hemiparesis four days after hitting his neck against a bed rail. Cerebral angiography showed complete occlusion of the right extracranial internal carotid artery 1.5 cm distal to its origin and emboli in distal branches of the right middle cerebral artery. He was treated conservatively. The second case: A 32 year-old man developed disturbance of consciousness with motor aphasia and right hemiparesis a few hours after hitting his chest and neck against baggage hanging from a crane. Cerebral angiography showed complete occlusion of the left middle cerebral artery and no abnormalities of the left internal carotid artery. He was treated with STA-MCA anastomosis two weeks after the accident. The third case: An 84 year-old man, who failed in a suicidal hanging, was semicomatose on admission and had right hemiparesis. Computed tomography demonstrated massive cerebral infarction of the territory of both anterior and left middle cerebral arteries. Cerebral angiography showed linear shadow defect of the left extracranial internal carotid artery corresponding with the site of the ligature. He was treated conservatively. From these angiographic findings, it was thought that intimal tear, intramural hematoma, vasospasm of the internal carotid artery and emboli given might bring about cerebral infarction. In such cases of blunt cervical trauma, cerebral angiography should be undertaken as soon as possible if focal cerebral ischemic symptoms can be seen.(ABSTRACT TRUNCATED AT 250 WORDS)     

Trapping and vascular reconstruction for ruptured fusiform aneurysm in the proximal A1 segment of the anterior cerebral artery

A 65-year-old woman presented with subarachnoid hemorrhage (SAH). Angiography detected a small bulge in the A1 segment of the right anterior cerebral artery (ACA). The patient was managed conservatively. Ten days after the initial SAH, the patient suffered a second SAH. Cerebral angiography demonstrated a fusiform aneurysm in the right A1 segment and vasospasm in the left A1 segment. The aneurysm of the right A1 segment was trapped and the right superficial temporal artery (STA) was end-to-end anastomosed to the distal portion of the right A1 segment. The patient had no postoperative cerebral ischemic events. Postoperative cerebral angiography revealed that the bypass flow through the right STA perfused the right ACA territories. STA-A1 end-to-end anastomosis can prevent cerebral ischemic events following parent vessel occlusion or microsurgical trapping for fusiform cerebral aneurysms in the A1 segment without sufficient collateral flow to the ipsilateral ACA territory from the contralateral ACA.     

Arterial graft to treat ruptured distal middle cerebral artery aneurysms in a patient with mucosa-associated lymphoid tissue lymphoma. Case report

A 60-year-old man was admitted to our hospital with sudden onset of motor aphasia, Gerstmann syndrome, and incomplete right hemiparesis one week after administration of chemotherapy for mucosa-associated lymphoid tissue (MALT) lymphoma. Computed tomography showed an intracerebral hematoma in the left subcortical area. Cerebral angiography revealed 2 aneurysms on the distal middle cerebral artery (MCA) that increased in size in the course of 2 weeks. The aneurysms were excised and a bypass placed using a superficial temporal artery (STA) graft. Histological study showed no bacteria, infiltration of inflammatory cells, or lymphoma cells in the aneurysm wall. The chemotherapy against MALT lymphoma was highly effective, so we presumed that the lymphoma cells had disappeared. The source of the distal MCA aneurysms was thought to be oncotic. Distal MCA aneurysms caused by MALT lymphoma are extremely rare. Surgical reconstruction using the STA may be effective in patients with ruptured distal MCA aneurysms if the wall is intact.     

Left to right ratio of transcranial color-coded sonography for monitoring hyperperfusion syndrome after carotid artery stenting: a case report

Hyperperfusion syndrome is a significant complication after carotid endarterectomy (CEA) or carotid artery stenting (CAS). A few reports have shown that an increase in the ratio of mean flow velocity (MFV) of the middle cerebral artery (MCA) of the affected side by transcranial color-coded sonography (TCCS) is useful for the evaluation of hyperperfusion after CEA or CAS. We report a case of hyperperfusion syndrome after CAS in which not only the increased ratio of the affected side based on preoperative mean flow velocity, but also the left to right ratio (L/R ratio) was useful for monitoring hyperperfusion. A 48-year-old man was admitted to our hospital because of cerebral infarction of the right internal carotid artery (ICA) due to stenosis of the right ICA at origin. The preoperative L/R ratio of MFV of the MCA by TCCS was 0.58. We performed CAS and the patient then developed hyperperfusion syndrome with epilepsy and was intubated under the management of strict blood control. We performed TCCS daily and the patient was extubated when the L/R ratio of MFV of the MCA decreased to 1.1 from a maximum of 2.6, although the increased ratio of MFV of the MCA of the affected side was still higher than 1.4. The patient went home without any complications from hyperperfusion. When there is preoperative laterality of cerebral blood flow, the L/R ratio of MFV by TCCS can be useful for monitoring hyperperfusion after CEA or CAS.     

Patch angioplasty to repair the arteriotomy defect in the wall of the middle cerebral artery after failure of superficial temporal artery-middle cerebral artery anastomosis in moyamoya disease--case report

A 65-year-old woman presented with moyamoya disease associated with a saccular aneurysm of the posterior cerebral artery. The surgical plan required superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis to be conducted before neck clipping of the aneurysm to provide collateral flow via the STA to prevent ischemia if temporary occlusion of the parent artery of the aneurysm was needed. However, the anastomotic procedure failed because the STA was occluded at the site of temporary clip application. End-to-end anastomosis of the STA was planned after excising the occluded site of the STA, but end-to-end anastomosis could not be performed because the donor artery was too short for anastomosis to the branch of the MCA. Therefore, patch grafting using a piece of wall of the STA was performed to repair the arteriotomy defect in the wall of the MCA, followed by neck clipping of the saccular aneurysm in the posterior circulation via the subtemporal approach. Vascular reconstruction can be recommended if arterial anastomosis between a superficial skin artery and a branch of the MCA is impossible due to an intraoperative accident or technical difficulty and reperfusion is necessary.     

Diagnosis and treatment of nontraumatic dissecting aneurysm in the middle cerebral artery]

Two cases of nontraumatic dissecting aneurysm of the middle cerebral artery (MCA) are reported. A 59-year-old woman presented with subarachnoid hemorrhage, mainly in the right sylvian fissure. On admission, the right carotid angiogram revealed a dissecting aneurysm with a double lumen extending from segment M1 to M2 of the right MCA, and an unruptured saccular aneurysm in the right internal carotid artery. Emergency surgery revealed a discolored protrusion of the arterial wall in the right MCA, which was thought to be the cause of her subarachnoid hemorrhage. The protrusion of the arterial wall was clipped and coated with Bemsheet soaked in Biobond. However, disturbance of consciousness persisted and she died of paralytic ileus two months after the operation. The other patient was a hypertensive 33-year-old woman with right hemiparesis and motor dysphasia. CT scans obtained on the day of admission showed no abnormalities. She was treated conservatively with clinical improvement, but CT scans obtained 3 days after the ictus revealed an infarction deep in the left frontal lobe. A left carotid angiogram was made 4 days after ictus and demonstrated severe stenosis of the proximal segment of the left MCA with poor filling of its superior trunk. Despite improvement of her hemiparesis, CT scans obtained 3 weeks after the ictus showed hemorrhagic infarction in the left frontal lobe. Repeat left carotid angiogram revealed a double lumen in the C1 and M1 portions with improvement of the previous severe stenosis of the M1. The 23 reported cases of DA in the MCA with our cases are reviewed and their neuroradiological and clinical features are discussed.     

Superficial temporal artery to middle cerebral artery anastomosis. Intraoperative evaluation by fluorescein angiography and xenon-133 clearance.

Fluorescein angiography and xenon-133 (133Xe) clearance studies were performed during surgery on 15 patients who were undergoing superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis. Fourteen patients had occlusive disease of the internal carotid artery (ICA), and one patient had severe stenosis of the MCA. Before anastomosis, fluorescein angiography showed slow filling of the MCA branches through collateral channels. Focal areas of impaired microcirculatory filling and washout were seen in the territory of severely sclerotic cortical arteries. The findings of preanastomotic 133Xe clearance studies were variable and a uniform pattern of regional cerebral blood flow (rCBF) changes was not defined. In 55% of the patients, rCBF was reduced to 25 ml/100 gm/min or less at one or more detector sites. Fluorescein angiography provided an immediate assessment of anastomotic patency and clearly displayed the distribution of blood entering the epicerebral circulation through the STA. In 67% of patients, multiple MCA cortical branches filled with fluorescein, whereas in 33% filling was restricted to the receptor artery territory. An immediate, substantial (greater than or equal to 15 ml/100 gm/min) increase in rCBF was demonstrated in 73% of patients after anastomosis. The rCBF changes were consistently better in patients with donor and receptor arteries greater than 1 mm in diameter. Redistribution of collateral input acted to increase rCBF in areas distant from the anastomotic site. Some improvement in fluorescein circulation and rCBF also was seen in cortex supplied by sclerotic MCA branches.     

Spontaneous dissecting aneurysms of anterior and middle cerebral artery associated with brain infarction: a case report and review of the literature

BACKGROUND

Intracranial dissecting aneurysms have been reported with increasing frequency and are recognized as a common cause of stroke. In some reviews and case reports, attempts have been made to compare the outcomes of surgical and medical treatments. However, the appropriate management of dissecting aneurysms in the anterior circulation remains controversial, especially in patients who also manifest cerebral infarction.

CASE DESCRIPTION

A 45-year-old male was diagnosed as having a dissecting aneurysm of the right middle cerebral artery (MCA) with cerebral infarction. In the course of conservative treatment, he developed a new cerebral infarction in the territory of the right anterior cerebral artery (ACA). Repeat cerebral angiograms revealed an increase in the aneurysmal dilatation of the right M2 and the appearance of a segmental dilatation of the right A2. He continued to be treated conservatively and his course was satisfactory. On subsequent angiograms, we observed resolution of the right A2 dissection and no further progression of the dilatation of the right M2.

CONCLUSION

This is the first reported case of simultaneous idiopathic dissecting aneurysms of different major arterial branches in the anterior circulation. Our review of the literature disclosed 36 and 23 cases, respectively, of dissecting aneurysms of the ACA and MCA. Many previously reported patients with these dissecting aneurysms involving subarachnoid hemorrhage (SAH) underwent surgery, which resulted in better outcome. More than half of the patients with ACA and MCA dissecting aneurysms had cerebral infarction. All ACA dissecting aneurysms involving ischemia occurred in the A2 region. The outcomes of both surgical and conservative management were equally satisfactory. On the other hand, in patients with MCA dissecting aneurysms, the area of ischemia frequently involved the M1 region; in these patients, conservative treatment resulted in poor outcomes. Therefore, revascularization distal to the compromised artery should be considered in patients with MCA-dissecting aneurysms who have ischemia. Careful interpretation of serial angiograms and/or magnetic resonance (MR) images is necessary because of the possibility of disease progression. If the aneurysmal size increases or there is progression of ischemic symptoms in the course of conservative treatment, surgery must be urgently evaluated.     

“Reverse” Bypass Using a Naturally Formed “Bonnet” Superficial Temporal Artery in Symptomatic Common Carotid Artery Occlusion: A Case Report

We herein describe a patient with symptomatic common carotid artery occlusion who underwent a reverse superficial temporal artery (STA)-middle cerebral artery (MCA) single bypass using a naturally formed “bonnet” STA. The surgical procedure was performed without difficulty, and no further neurological deterioration was observed after surgery. In practice, this case highlights that the reverse STA-MCA bypass can be achieved safely and less invasively using a naturally formed “bonnet” STA.     

The feasibility of detecting cerebral blood flow direction using the indocyanine green video angiography

The intraoperative confirmation of blood flow direction is necessary in cerebral vascular surgery. Using indocyanine green video angiography (ICG-VAG) with the FLOW 800 system, we examined the transit time of the blood vessel of interest and semiquantitatively evaluated the delay time (T1/2max) from indocyanine green (ICG) injection into the donor artery in reconstructive surgery and the middle cerebral artery (MCA) in aneurysmal surgery. The direction of cerebral blood flow (CBF), which can often be confirmed by ICG-VAG, may be more difficult to determine with faster blood flow. Here, we report our findings regarding the feasibility of detecting CBF direction using the FLOW 800 system. Twenty patients undergoing superficial temporal artery (STA) to MCA anastomosis for carotid occlusive disease and 13 patients with a small MCA aneurysm clipping were evaluated using the T1/2max, semiquantitative method with the FLOW 800 system. In STA–MCA anastomosis cases, the regions of interest (ROIs) included: the proximal donor STA and a region more than 10 mm on the distal side of the donor STA near the anastomosis site. In MCA aneurysms, the ROIs included the proximal M1 and distal M2 sides of the MCA aneurysm. T1/2max was significantly shorter for the proximal sites compared to the distal sites for all subjects (ps?<?0.01). T1/2max was shorter for all subjects in the proximal sites. The direction of CBF can be determined using the FLOW 800 system.