Superficial temporal artery-middle cerebral artery (STA-MCA) bypass for steno-occlusive cerebrovascular disease prevents future ischemic stroke by improving cerebral blood flow (CBF). Cerebral ischemia and hyperperfusion are potential complications of this procedure during the early postoperative period. We designed this study to investigate the efficacy of neuroradiological evaluation during early postoperative period after revascularization to detect postoperative pathological conditions of the brain and to avoid these complications. Eight consecutive patients (7 men and 1 woman; mean age 62.6 years) suffering from cerebral ischemia due to occlusive cerebrovascular disease with hemodynamic compromise were enrolled in this study. The underlying pathological condition was internal carotid artery (ICA) or MCA occlusion in 7 cases and MCA severe stenosis in 1 case. The standard STA-MCA bypass was performed for all cases.
Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) were performed on the day after surgery, and single photon emission computed tomography (SPECT) was performed 1 and 7 days after surgery. Postoperative MRA on Day 1 showed patency of the bypass in all cases. Postoperative MRI on Day 1 revealed no ischemic or hemorrhagic complications in any of the cases. Postoperative SPECT showed transient focal intense increase in CBF around the sites of anastomosis in all 8 cases. Intensive blood pressure control was performed to prevent symptomatic hyperperfusion. All cases were discharged without perioperative complications with an average of 19.8 days of postoperative hospital stay.
Neuroradiological evaluation during the early postoperative period enables safe perioperative management by revealing underlying pathological conditions of the brain following revascularization surgery.

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We describe microsurgical training methods for novice operators using gauze and tubes. Seven training methods were designed, and a neurosurgeon without microsurgical experience practiced these methods every day for about 3 years. After completing training, the neurosurgeon performed superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis, A3-A3 bypass, and occipital artery-posterior inferior cerebellar artery (OA-PICA) bypass.
These training methods contribute to improving microsurgical technique, especially microvascular anastomosis, of novice operators.

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Direct revascularization surgery for moyamoya disease has been established as an effective and safe surgical treatment. But it is unclear that the relationship between the specific postoperative clinical course and drastic change of cerebral hemodynamics resulted from the bypass procedure. Despite recent studies demonstrating the techniques to measure local cerebral blood flow intraoperatively using various instruments, there are no reports in the literature that investigate the correlation between intraoperative change of flow direction/velocity (not volume) in recipient artery and postoperative cerebral hemodynamics and clinical course.
In this study, we measured the flow direction/velocity of recipient artery intraoperatively using Doppler flowmeter before and after bypass surgery. The results throw light on the association of cerebral hemodynamics and postoperative clinical course in patients with moyamoya disease.

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Definite indications for the treatment of unruptured cerebral aneurysm (uAN) are very difficult to establish because the risk of rupture for any individual aneurysm still cannot be estimated. Furthermore, the criteria for evaluation of the prognosis and potential complications remain unclear, so no risk-benefit analysis can be performed. Recently, prevention of adverse effects to improve patient safety and satisfaction have become more important in the field of neurosurgery. We analyzed the occurrence and nature of adverse effects in 156 consecutive patients treated for uAN in our institute.
The patients were treated with endovascular coil embolization for mainly paraclinoid or basilar apex aneurysms in 17 men and 38 women aged 35-81 years (mean 62.1±10.0 years) or surgical clipping for other aneurysms in 23 men and 78 women aged 35-77 years (mean 58.4±9.9 years). Anterior cerebral, anterior communicating, and middle cerebral artery aneurysms were significantly more common in the clipping group, whereas internal carotid and vertebrobasilar artery aneurysms were significantly more common in the coil group.
Selection and treatment of uAN by our team showed generally good results in the short term. However, long-term observation to detect such complications as recurrence is required. Serious adverse events occurred in 17 of all 156 patients (10.9%), including mortality in 1 patient (0.6%), major morbidity (less than modified Rankin scale score 2) in 1 patient (0.6%), minor morbidity in 3 patients (1.9%), and transient neurological deficits in 12 patients (7.7%). The incidence of serious adverse events was similar in the coil and clipping groups, but all events including minor, transient, and other adverse events were significantly (p<0.05) more common in the clipping group.
No permanent motor deficit occurred in the clipping group, and intraoperative use of the mirror, endoscope, Doppler flowmeter, fluorescence angiography, and electrophysiological monitoring including motor evoked potential (MEP) were considered to be very important to avoid ischemic complications. Unexpectedly common postoperative seizures may indicate that adequate saturation of anticonvulsant agent is necessary before surgery. The many problems caused by craniotomy should be recognized as avoidable complications. Unfortunately, serious postoperative neurological deficits were also frequently encountered. Endovascular coil embolization provides a complementary treatment to surgical clipping because no re-treatment of coil embolization or clipping was required for problems such as perforator injury surrounding the basilar apex or optic nerve damage. However, 1 patient died of vessel laceration during neck plasty, so improvement of procedures is essential.

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We examined the operative findings of cerebral aneurysms that grew during follow-ups over the past 5 years. We defined aneurysmal growth as form change such as the bleb formation or more than 2-mm growth compared with past findings. In operation, we confirmed a very thin wall of cerebral aneurysm correspond to aneursymal growth during follow-up.
Rupture rates appear to be high in aneurysms caused by a change such as the above. Clipping can prevent aneurysmal rupture in these cases.

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Endoscopic surgery for spontaneous cerebral hemorrhage is less invasive surgery. However, the management of spontaneous cerebral hemorrhage remains controversial. We compared the surgical results and outcomes at discharge of cerebellar hemorrhage patients who underwent craniotomy with those of patients who received endoscopic surgery.
Patients treated by endoscopic surgery (n=11) were compared with patients treated by conventional surgical hematoma evacuation (n=14). The endoscopic surgery took less time than the craniotomy (67.8 min vs. 207.1 min, p<0.01). The period of ventricular drainage was shorter in the endoscopic surgery group (1.8 days vs. 5.8 days). There was no significant difference in the hematoma evacuation rate between the craniotomy group and the endoscopic surgery group. There was no re-bleeding in the endoscopic surgery group, and no patients in this group required cerebrospinal fluid shunt surgery. Outcome at discharge was not significantly different between the craniotomy and endoscopic surgery groups.
We believe that endoscopic surgery is an effective, safe and less invasive technique for treating patients with cerebellar hemorrhage.

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After the International Subarachnoid Trial reported favorable outcome in a coiling group in treatment for ruptured cerebral aneurysms, we changed our strategy as follows. We performed cerebral angiography as soon as possible after onset, and treated aneurysms by coiling as our primary choice. In this paper, we report our treatment and results over the past 4 years (2006-2010), and discuss the role and limitation of coiling. In the first half period (January in 2006-March in 2008), we performed clipping in 52 cases and coiling in 23 cases. On the other hand, in the second half period (March in 2008-March in 2010), more than half of aneurysms were embolized (44 coiling and 38 clipping). Many anterior (Acom) and posterior communicating artery aneurysms were treated by coiling in the second half, while those in the first half were treated by clipping. Coiling was difficult in a few Acom aneurysms, because of their shape and access route up to the aneurysms. Most middle cerebral aneurysms were cured by clipping in both periods. Hospitalization was shortened in the second half, although modified Rankin scale at discharge was the same in both periods.
Coiling seemed to be effective in treatment for half of ruptured aneurysms. However, care must be taken in considering coiling for Acom aneurysms.

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Early recognition of stroke signs and symptoms is essential for early treatment and improvement of clinical outcomes. We performed a stroke education program for junior high school students and their parents. In February 2010, 79 students in 2 classes of the 1st grade of a junior high school and their parents were enrolled. Subjects were divided into 2 groups: an intervention class (39 students) and a control class (40 students). Students in the intervention class received a 45-minute lesson about stroke signs and symptoms. This group was taught the FAST message (Facial droop, Arm weakness, Speech disturbance, Time to call 119), and stroke risk factors. School items consisting of a pen, file, magnet, sticky note with the FAST message, and stroke pamphlets were also distributed to students in the intervention class. Parents of the intervention class were educated indirectly through the stroke pamphlets and items. For all subjects, questionnaires on stroke knowledge were examined at the baseline and immediate post-lesson time-points and 3 months after the stroke lesson.
In students, the percentages of correct answers did not differ significantly between the 2 classes at the baseline. Three months after the stroke lesson, students in the intervention class answered more correctly than in the control class to the questions of facial palsy (97% in the intervention class vs. 55% in the control class; P<0.0001), speech disturbance (100% vs. 83%; P=0.006), calling 119 for stroke (90% vs. 55%; P=0.001), smoking (87% vs. 63%; P=0.012), hypertension (92% vs. 73%; P=0.021) and the FAST message (97% vs. 13%; P<0.0001). Parents of the intervention group also answered more correctly the question of the FAST message (82% vs. 19%; P<0.0001) than did the control group 3 months after the stroke lesson.
We demonstrated that the stroke education program for junior high school students and their parents improved their stroke knowledge, especially of the FAST message.

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We evaluated the usefulness of medullary trigeminal evoked potential monitoring (M-TEP) and fluorescence cerebral angiography using fluorescein sodium (fluorescein-FCAG) for detecting the blood flow insufficiency in the posterior inferior cerebellar artery (PICA) during aneurysm surgery.
The study population consisted of 3 patients with PICA aneurysm (2 cases) and vertebral artery aneurysm (1 case). In 2 cases, after aneurysm clipping and/or trapping, M-TEP disappeared and the fluorescence of the PICA was not seen. After clip replacement (Case 1) and occipital artery (OA) - PICA anastomosis (Case 2), M-TEP returned to the control level and blood flow of PICAs were confirmed by fluorescein-FCAG. Postoperatively, incomplete Wallenberg syndrome appeared in Case 2. In Case 3, OA-PICA anastomosis was performed, and the aneurysm was trapped. Intraoperative findings of M-TEP and fluorescein-FCAG did not change. No neurological deficits appeared postoperatively.
Based on our findings, we suggest that M-TEP and fluorescein-FCAG are useful to prevent unexpected postoperative Wallenberg syndrome and to improve the surgical outcome.

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A small part of the patients with subarachnoid hemorrhage (SAH) are not properly diagnosed until they suffer ischemic neurological deficits and/or rebleeding during vasospasm. We therefore investigated the clinical profile of such patients.
We retrospectively analyzed 581 patients with aneurysmal SAH experienced in our institute between 2001 and 2009. Patient’s characteristics, presence and severity of headache before final diagnosis, imaging investigations they received, their World Federation of Neurological Surgeons (WFNS) grades at admission, the location of aneurysm, treatment, and outcome at discharge were investigated.
Five patients were not correctly diagnosed until they presented neurological deficits due to vasospasm or experienced simultaneous rebleeding. Their mean age was 69.4, and all were female. Although all patients had a bad headache, they did not undergo any imaging examinations. Immediate coil embolization was performed for 2 patients, 1 died due to rupturing during embolization procedure. The other 3 were treated by open clipping surgery (2 delayed and 1 immediate). Four patients had some disability as a sequel, and their outcomes were significantly worse compared with 53 patients with SAH in WFNS Grade II.
The patients with SAH who had not been properly diagnosed in the acute stage had a poor outcome. We should be very careful when we see patients complaining of severe headache.

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We report a case of extracranial internal carotid artery aneurysm successfully treated with aneurysmal resection and primary end-to-end anastomosis of the proximal and distal internal carotid artery. An 82-year-old woman presented with dysphagia and discomfort of the throat. Magnetic resonance imaging showed a giant aneurysm, and angiography revealed an unruptured partially thrombosed giant aneurysm of 4-cm diameter located in her right extracranial internal carotid artery. Aneurysmal resection and primary end-to-end anastomosis of internal carotid artery were performed. Postoperative computerized tomography angiograms showed that the aneurysm had disappeared and that the patency of the right internal carotid artery was preserved. The postoperative course was uneventful, and her symptoms improved.
We propose that primary end-to-end anastomosis is an ideal method for treating aneurysms because it can maintain antegrade cerebral perfusion and is minimally invasive.

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