Although the pathogenesis of moyamoya disease (MMD) has not been fully elucidated, the effectiveness of surgical revascularization in preventing stroke has been addressed by many studies. The main mechanism of surgical revascularization is augmenting the intracranial blood flow using an external carotid system by either direct bypass or pial synangiosis. This can improve resting cerebral blood flow as well as vascular reserve capacity. For direct revascularization, the superficial temporal artery is used as the donor artery in most cases, although the occipital artery may be used in limited cases. Usually, the cortical branch of the middle cerebral artery is selected as the recipient of direct anastomosis. As for indirect revascularization, various techniques using different kinds of connective tissues have been introduced. In some cases, reinforcing the anterior cerebral artery and the posterior cerebral artery territories can be considered. The effectiveness of surgical revascularization for preventing ischemic stroke had been generally accepted by many studies. However, for preventing hemorrhagic stroke, new evidence has been added by a recent randomized controlled trial. The incidence of peri-operative complications such as stroke and hyperperfusion syndrome seems to be high due to the nature of the disease and technical demands for treatment. Preventing and adequately managing these complications are essential for ensuring the benefits of surgery.
Anterior Cerebral Artery ; Arteries ; Cerebral Revascularization ; Connective Tissue ; Humans ; Incidence ; Middle Cerebral Artery ; Moyamoya Disease* ; Posterior Cerebral Artery ; Stroke ; Temporal Arteries ; Tissue Donors ; Treatment Outcome

Although the pathogenesis of moyamoya disease (MMD) has not been fully elucidated, the effectiveness of surgical revascularization in preventing stroke has been addressed by many studies. The main mechanism of surgical revascularization is augmenting the intracranial blood flow using an external carotid system by either direct bypass or pial synangiosis. This can improve resting cerebral blood flow as well as vascular reserve capacity. For direct revascularization, the superficial temporal artery is used as the donor artery in most cases, although the occipital artery may be used in limited cases. Usually, the cortical branch of the middle cerebral artery is selected as the recipient of direct anastomosis. As for indirect revascularization, various techniques using different kinds of connective tissues have been introduced. In some cases, reinforcing the anterior cerebral artery and the posterior cerebral artery territories can be considered. The effectiveness of surgical revascularization for preventing ischemic stroke had been generally accepted by many studies. However, for preventing hemorrhagic stroke, new evidence has been added by a recent randomized controlled trial. The incidence of peri-operative complications such as stroke and hyperperfusion syndrome seems to be high due to the nature of the disease and technical demands for treatment. Preventing and adequately managing these complications are essential for ensuring the benefits of surgery.
Anterior Cerebral Artery ; Arteries ; Cerebral Revascularization ; Connective Tissue ; Humans ; Incidence ; Middle Cerebral Artery ; Moyamoya Disease* ; Posterior Cerebral Artery ; Stroke ; Temporal Arteries ; Tissue Donors ; Treatment Outcome

BACKGROUND AND PURPOSE: Quantitative magnetic resonance angiography (Q-MRA) enables direct measurement of volume flow rate (VFR) of intracranial arteries. We aimed to evaluate the collateral flows in internal carotid artery (ICA) occlusion with primary collateral pathway via circle of Willis using Q-MRA, and to compare them between patients who recently developed ipsilateral symptomatic ischemia and those who did not. METHODS: Between 2012 and 2014, 505 patients underwent Q-MRA in our institution. Among these, 33 patients who had unilateral ICA occlusion with primary collateral pathway were identified, and grouped into asymptomatic patients, stable patients with chronic infarction, and symptomatic patients with acute/subacute infarction. Mean VFR (mVFR) in intracranial arteries was measured and compared between the patients' groups. Kruskal-Wallis test was used for statistical analysis. RESULTS: Six patients were asymptomatic, fifteen with chronic infarction were stable, and twelve with acute/subacute infarction were symptomatic. The mVFR of ipsilateral middle cerebral artery in symptomatic patients was significantly lower than those in stable or asymptomatic patients (73.7+/-45.6 mL/min vs. 119.9+/-36.1 mL/min vs. 121.8+/-42.0 mL/min; P = 0.04). Total sum of the mVFR of ipsilateral anterior, middle, and posterior cerebral arteries was significantly lower in symptomatic patients than those in other groups (229.3 +/- 51.3 mL/min vs. 282.0+/-68.6 mL/min vs. 314.0+/-44.4 mL/min; P = 0.02). CONCLUSIONS: Q-MRA could be helpful to demonstrate the difference in the degree of primary collateral flow in ICA occlusion between the patients with recent symptomatic ischemia and those without.
Arteries ; Carotid Artery, Internal* ; Circle of Willis ; Collateral Circulation ; Humans ; Infarction ; Ischemia ; Magnetic Resonance Angiography* ; Middle Cerebral Artery ; Posterior Cerebral Artery

PURPOSE: To evaluate the cerebral hemodynamic changes during interictal period in patients with epilepsy, we investigated changes in cerebral blood flow velocities by transcranial Doppler sonography (TCD). METHODS: Blood flow velocities and pulsatility indecies were measured in both anterior cerebral arteries, middle cerebral arteries, posterior cerebral arteries, internal carotid arteries, and basilar artery using TCD in 21 patients with epilepsy and 21 age and sex matched normal adults. We also evaluated the effects of seizure type, seizure frequency, EEG findings, and anticonvulsant medication on cerebral blood flow velocities. RESULTS: The blood flow velocities of cerebral arteries were decreased in patients, but the pulsatility indecies weren't different. Cerebral blood flow velocities were influenced by seizure type, EEG findings, or anticonvulsant medication. CONCLUSION: Our study demonstrates that cerebral blood flow velocities might be decreased during interictal period in patients with epilepsy, and suggests that TCD is an useful method for the investigation of the cerebral hemodynamic changes in epilepsy.
Adult ; Anterior Cerebral Artery ; Basilar Artery ; Blood Flow Velocity ; Carotid Artery, Internal ; Cerebral Arteries ; Electroencephalography ; Epilepsy* ; Hemodynamics ; Humans ; Middle Cerebral Artery ; Posterior Cerebral Artery ; Seizures ; Ultrasonography, Doppler, Transcranial

We provide the examination technique and the normal values of the cerebral blood flow velocity assessed with the transcranial doppler ultrasound system (TC2-64B, EME) operating at 2MHz in 50 volunteer adult subjects who had no history of neurological illness. Their age ranged from 20 to 58 years and 30 were men. We examined the middle cerebral artery (MCA), the anterior cerebral artery (ACA), the posterior cerebral artery (PCA), the internal carotid (ICAl the opthalmic artery (OPA), and the basilar artery (BA). For each artery we analyzed peak systolic, peak diastolic. And mean flow velocity. Reference values of mean velocities (cm/sec) were 53.2-58.5 for MCA; 48.7-53.8 for ACA; 30.8-33.2 for PCA; . 38.6-42.5 for ICA;11.7-13.1 for OPA;and 34.2-39.9 for BA (95% confidence interval). The velocities correlated inversely with age (p<0.05) arld were significantly lower in the posterior circulation (PCA and BA) than in anterior circulation (MCA, ACA and ICA). There was no difference between both.sexes and between the right and the left side.
Adult ; Anterior Cerebral Artery ; Arteries ; Basilar Artery ; Blood Flow Velocity* ; Humans ; Male ; Middle Cerebral Artery ; Passive Cutaneous Anaphylaxis ; Posterior Cerebral Artery ; Reference Values ; Ultrasonography* ; Volunteers

Hypoplasia of the internal carotid artery is a rare congenital anomaly. Agenesis, aplasia, and hypoplasia of the internal carotid artery (ICA) are frequently associated with cerebral aneurysms in the circle of Willis. Authors report two cases with congenital hypoplasia of the ICA accompanying with the aneurysms. Transfemoral cerebral angiography (TFCA) in one patient identified nonvisualization of the left ICA. Bilateral anterior cerebral artery (ACA) and middle cerebral artery (MCA) were supplied from the right ICA accompanying with two aneurysms at anterior communicating artery (AcoA) and A1 portion of the left ACA. TFCA in another patient demonstrated hypoplastic left ICA and left ACA filled from the right ICA accompanying with AcoA aneurysm. Left MCA was filled from basilar artery via posterior communicating artery (PcoA). Skull base computed tomography (CT) in two patients showed hypoplastic carotid canal. Authors performed direct aneurysmal neck clipping. Follow up CT angiography (CTA) at one year after surgery did not show regrowth or new development of the aneurysm. In patients with hypoplastic ICA, neurosurgeons should be aware of the possibility of development of the aneurysms, presumably because of hemodynamic process. Direct aneurysmal neck clipping is a good treatment modality. After operation, regular CTA, magnetic resonance angiography (MRA) or TFCA is needed to find progressive lesion and to prevent cerebrovascular attack (CVA).
Aneurysm ; Angiography ; Anterior Cerebral Artery ; Arteries ; Basilar Artery ; Carotid Artery, Internal* ; Cerebral Angiography ; Circle of Willis ; Follow-Up Studies ; Hemodynamics ; Humans ; Intracranial Aneurysm ; Magnetic Resonance Angiography ; Middle Cerebral Artery ; Neck ; Skull Base

PURPOSE: The angiographic demonstration of absent cerebral blood flow is presently considered to be the most reliable method of confirming brain death. The purpose of this study is to determine whether CT angiography (CTA) with spiral CT can rapidly and specifically establish a diagnosis of brain death. MATERIALS AND METHODS: A total of fifteen CT angiograms (brain death, n=9;severe coma, n=6 within 24 hours of the study) were obtained prospectively in 12 patients with an established clinical diagnosis; Two patients underwent repeated CTA. Twenty seconds after beginning the injection of contrast media (100 mL at a rate of 3 mL/sec), CT scanning (30 -second continuous exposure and 60 -mm length) was performed with a table speed of 2 mm/sec and a section thickness of 2 mm. For each case, the presence or absence of opacification of inter-nal carotid arteries (ICA), vertebral and basilar arteries (VBA), anterior cerebral arteries (ACA), middle cerebral arteries (MCA), posterior cerebral arteries (PCA), distal branches of cerebral arteries, and superficial temporal arteries (STA) was ascertained. RESULTS: Except in one clinically brain-dead patient, whose EEG was difficult to interpret due to excessive arti-facts, the distal branches of cerebral arteries did not opacify. STA, on the other hand, was always visible on both sides. In all brain-dead patients but three, the ICA and proximal ACA, MCA, or PCA escaped visualiza-tion. In the remaining three cases with large skull defect or skull fracture, however, CT angiography showed faint opacification of the ICA and proximal segments of cerebral arteries. Cerebral arterial flow was preserved in all six patients in whom there was no clinical evidence of brain death. CONCLUSION: CTA may be used as a confirmatory test for the determination of brain death.
Angiography* ; Anterior Cerebral Artery ; Basilar Artery ; Brain Death* ; Brain* ; Carotid Arteries ; Cerebral Arteries ; Coma ; Contrast Media ; Diagnosis ; Electroencephalography ; Hand ; Humans ; Middle Cerebral Artery ; Passive Cutaneous Anaphylaxis ; Posterior Cerebral Artery ; Prospective Studies ; Skull ; Skull Fractures ; Temporal Arteries ; Tomography, Spiral Computed ; Tomography, X-Ray Computed ; United Nations

PURPOSE: To evaluate the findings of angiography and high-resolution CT of the skull base in the patients with congenital absence or hypoplasia of the unilateral internal carotid artery. MATERIALS AND METHODS: Eight patients with congenital unilateral absence (n=6) or hypoplasia (n=2) of the internal carotid artery were included in this study. None showed symptoms related to the absence of the artery. All underwent selective arteriography and six underwent high-resolution CT of the skull base. The angio-graphic findings of the carotid artery and collateral pathways to the absent side, as well as the high-resolution CT findings of the bony carotid canal at the skull base, were evaluated. RESULTS: In all cases, intracranial collaterals were of the adult type. The anterior cerebral arteries were supplied via the anterior communicating artery in all patients, and the middle cerebral arteries via the posterior communicating artery in five. In two, collateral flows were supplied by both the anterior and posterior communicating arteries, and in four, high-resolution CT of the skull base showed remnants or sclerosis of the carotid canal. One patient showed a hypoplastic bony carotid canal, and in one, this canal was absent. Intracranial aneurysms were found in four patients; in three, thses were located at the anterior communicating artery, and in the other, at the posterior cerebral artery. In four of six patients with no internal carotid artery, the ophthalmic arteries were opacified via the middle meningeal artery. CONCLUSION: In cases involving congenital absence or hypoplasia of the internal carotid artery, differentiation between agenesis and aplasia may be based on the pattern of collateral circulation. High-resolution CT find-ings may suggest that this change has a congenital origin.
Adult ; Angiography* ; Anterior Cerebral Artery ; Arteries ; Carotid Arteries ; Carotid Artery, Internal* ; Collateral Circulation ; Humans ; Intracranial Aneurysm ; Meningeal Arteries ; Middle Cerebral Artery ; Ophthalmic Artery ; Posterior Cerebral Artery ; Sclerosis ; Skull Base* ; Skull*

In a series of 375 bilateral carotid angiographies, two accessory middle cerebral arteries, one duplication of the middle cerebral artery demonstrated on the angiography were reviewed relative to the pertinent literature. These anomalous middle cerebral arteries are very rare. We reported a case of duplication of the middle cerebral artery at 1993 which was first one to be reported in Korea. At present, we report two additional anomalous accessory middle cerebral arteries. Among these, one was accessory middle cerebral artery originated from the horizontal portion of the anterior cerebral artery, and the other originated from the A2 segment of the anterior cerebral artery. Both of these gave rise to some perforating arteries.
Angiography ; Anterior Cerebral Artery ; Arteries ; Korea ; Middle Cerebral Artery*

OBJECTIVE: The aim of study was to review our patient population to determine whether there is a critical aneurysm size at which the incidence of rupture increases and whether there is a correlation between aneurysm size and location. METHODS: We reviewed charts and radiological findings (computed tomography (CT) scans, angiograms, CT angiography, magnetic resonance angiography) for all patients operated on for intracranial aneurysms in our hospital between September 2002 and May 2004. Of the 336 aneurysms that were reviewed, measurements were obtained from angiograms for 239 ruptured aneurysms by a neuroradiologist at the time of diagnosis in our hospital. RESULTS: There were 115 male and 221 female patients assessed in this study. The locations of aneurysms were the middle cerebral artery (MCA, 61), anterior communicating artery (ACoA, 66), posterior communicating artery (PCoA, 52), the top of the basilar artery (15), internal carotid artery (ICA) including the cavernous portion (13), anterior choroidal artery (AChA, 7), A1 segment of the anterior cerebral artery (3), A2 segment of the anterior cerebral artery (11), posterior inferior cerebellar artery (PICA, 8), superior cerebellar artery (SCA, 2), P2 segment of the posterior cerebral artery (1), and the vertebral artery (2). The mean diameter of aneurysms was 5.47+/-2.536 mm in anterior cerebral artery (ACA), 6.84+/-3.941 mm in ICA, 7.09+/-3.652 mm in MCA and 6.21+/-3.697 mm in vertebrobasilar artery. The ACA aneurysms were smaller than the MCA aneurysms. Aneurysms less than 6 mm in diameter included 37 (60.65%) in patients with aneurysms in the MCA, 43 (65.15%) in patients with aneurysms in the ACoA and 29 (55.76%) in patients with aneurysms in the PCoA. CONCLUSION: Ruptured aneurysms in the ACA were smaller than those in the MCA. The most prevalent aneurysm size was 3-6 mm in the MCA (55.73%), 3-6 mm in the ACoA (57.57%) and 4-6 mm in the PCoA (42.30%). The more prevalent size of the aneurysm to treat may differ in accordance with the location of the aneurysm.
Aneurysm ; Aneurysm, Ruptured ; Anterior Cerebral Artery ; Arteries ; Basilar Artery ; Carotid Artery, Internal ; Caves ; Choroid ; Female ; Humans ; Incidence ; Intracranial Aneurysm ; Magnetic Resonance Angiography ; Male ; Middle Cerebral Artery ; Posterior Cerebral Artery ; Rupture ; Vertebral Artery