A trial construction of a database of cerebrovascular diseases was done recently by a study group organized by the Ministry of Health and Welfare. One purpose of the study group was to establish a data bank of cerebrovascular diseases to help realize medical progress in treatment of cerebrovascular diseases based on an analysis of the registered data. In this connection, a joint committee of 5 medical societies related to cerebrovascular diseases plans to make a treatment guideline of cerebrovascular diseases. A joint committee will begin revision work after the treatment guideline is published. It is necessary to inspect the clinical results for treatment carried out under the guideline in order to revise recommended treatments. The purpose of inspection and revision of the treatment guideline is also to realize progress in treatment of cerebrovascular diseases.
The construction of a nationwide system that registers clinical results treated according to the guideline with a data bank of cerebrovascular diseases is desirable so that a joint committee can inspect the efficacy of treatment recommended in the guideline.

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In selecting a treatment method at our hospital for unruptured cerebral aneurysm, we inform the patient of craniotomy and transcatheter embolization by GDC and allow the patient to choose between the procedures when it is determined that GDC embolization is likely to achieve complete or nearly complete occlusion.
This analysis is aimed at clarifying the treatment results of unruptured cerebral aneurysm after GDC was introduced at our hospital. The subjects were selected from 207 cases of craniotomy and 49 cases of transcatheter embolization by GDC performed between January 1998 and December 2001. We analyzed their morbidity (MB) and mortality (MT) for treatment evaluation. In 207 craniotomy cases, MT, transient MB and permanent MB were 0%, 4.5% and 2.2%, respectively. In transcatheter embolization, MT, transient MB and permanent MB were 0%, 4.0% and 0%, respectively. The overall result of the analysis showed MT 0%, transient MB 4.4% and permanent MB 1.8%, respectively. The surgery results based on our treatment guidelines were mostly excellent.
In selecting a treatment procedure for unruptured cerebral aneurysm, it is important to focus on obtaining sufficient occlusion and ensuring safety. When applying both craniotomy and transcatheter embolization, the patient should be fully informed and agree to the procedures.

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We investigated 235 cases of unruptured cerebral aneurysms experienced in the past 9 years. There were 117 operated and 118 unoperated cases. The decision to operate was made by the patients, who were informed that the rupture rate of the discovered aneurysms was 0.5-1.0% and surgical risks were about 5%. Observation was started just after the operation for operated cases and after radiological investigation was confirmed for the unoperated cases. A Rankin scale of II or worse was considered morbidity. Aneurysms were grouped according to the aneurysm size (small, below 5 mm; medium, 5-15 mm; large, over 15 mm). Surgical mortality was 0.9%, and morbidity was 2.7%. Surgical morbidity and mortality increased according to aneurysm size. The rupture rate of the unoperated cases increased as aneurysm size increased. The annual rupture rate of the small group was 0.4%, whereas the medium group was 6.4% and the large group was 11.4%. The rate of subarachnoid hemorrhage after treatment of the unruptured cerebral aneurysms was 0.2% per year. Based on these data, we investigated 2 groups of unoperated and operated patients using the Kaplan-Meyer curve and Log-Rank test. Concerning mortality, the operated cases had a significantly better outcome than unoperated cases. When morbidity was included, no significant efficacy was noted. However, in the medium group (5-15 mm size), patients undergoing surgery showed significantly better outcome.
These results indicate careful selection of the treatment of unruptured cerebral aneurysm is necessary. Observation may be indicated especially when the aneurysm size is below 5 mm.

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We reviewed the surgical outcomes and operative techniques for 42 paraclinoid aneurysms in 40 patients operated between 1995 and 2002. There were 20 ruptured and 22 unruptured aneurysms. Ophthalmic aneurysms were most common (29%), followed by superior hypophyseal (17%), carotid cave (17%), anterior carotid wall (17%) aneurysms, posterior wall aneurysms (12%), lateral wall aneurysms (7%), and genu aneurysms (5%). Thirty-eight aneurysms were clipped satisfactorily, 2 lateral wall aneurysms were wrapped with Vascwrap^®, one anterior wall aneurysm was treated by the clipping-on-wrapping method and another large superior ophthalmic aneurysm was treated by trapping and bypass techniques. Using the Glasgow Outcome Scale, surgical outcomes were excellent or good, 81%; fair, 2%; poor, 7%; and death, 10%. Complications directly related to surgical procedures included transient oculomotor nerve palsy, 2; new deficit in vision, 1; cerebrospinal fluid leak, 2; and cerebral infarction, 1. Technical prerequisites for safe surgery included 1) thinning the anterior clinoid process instead of removing it en bloc, 2) using coarse diamond, instead of fine burr, 3) obtaining sufficient mobility of the optic nerve and internal carotid artery by cutting the optic sheath and distal dural ring.
Our increased refinements in operative techniques have greatly improved the surgical treatment of paraclinoid aneurysms.

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Progress in diagnostic technology such as 3D-CTA and MRA has brought an increase in the surgical treatment of asymptomatic unruptured cerebral aneurysms (AUAn) and raised the importance of informed consent. We explain how we implement informed consent with patients with AUAn and report the results. This study covers 40 patients with 51 AUAns (16 males, 24 females, 63.8±9.1 years old) which were diagnosed between January 1996 and September 2001. Thirteen aneurysms were located at the internal carotid, 5 at the anterior cerebral, 25 at the middle cerebral, 8 at the vertebro-basilar artery. The decision to operate was based on the guideline of the Japanese Society for Detection of Asymptomatic Brain Diseases. Hemorrhage risk was explained to each patient with the use of a table that showed computed risk over a lifetime considering current age. Thirty patients with 35 aneurysms chose medical treatment. Thirty-four aneurysms (97.1%) were treated with clipping and 1 aneurysm (2.9%) with endovascular coil embolization. About 25 percent of patients selected for observation were selected for that group based on their own desire.
A table of computed hemorrhage risk over the course of a lifetime can show patients concrete numerical values. We believe it informed consent for patients with AUAn is effective.

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We retrospectively analyzed the results of our 16 years of experience in the treatment of unruptured upper basilar artery aneurysms by surgery or coil embolization.
This analysis involved 32 basilar tip aneurysms and 18 basilar superior cerebellar artery bifurcation aneurysms in 19 men and 31 women who ranged in age from 26 to 75 years (mean 57.0 years). Thirty-three aneurysms (66%) were small, 13 (26%) were large, and 4 (8%) were giant. Surgery were performed by 4 selected neurosurgeons and coil embolization was performed by 2 selected endovascular interventionalists. Treatment consisted of aneurysm neck clipping in 24, aneurysm coating in 5, and coil embolization in 21 patients.
Surgery was mainly performed by the transsylvian approach. Immediate anatomic outcomes demonstrated complete or near-complete occlusion in 16 aneurysms (76.2%). Five aneurysms (23.8%) could not be embolized because of anatomic difficulties. In small aneurysms, 24 of the 26 (91.3%) patients treated with surgery remained neurologically intact or unchanged from their initial clinical status. Procedure-related morbidity and mortality were 7.7% and 0%, respectively. In small aneurysms, 8 of the 9 (88.9%) patients treated with coil embolization remained neurologically intact or unchanged from their initial clinical status. Procedure-related morbidity and mortality were 11.1% and 0%, respectively. In large aneurysms, the postoperative courses were uneventful in all 3 (100%) patients treated with surgery. There was no procedure-related morbidity or mortality. Eight of the 10 (80%) patients with large aneurysms treated with surgery remained neurologically intact or unchanged from their initial clinical status. Procedure-related morbidity and mortality were 10% and 10%, respectively. There were 3 poor results (75%) in patients with giant aneurysms, including 1 death caused by premature rupture. One severe disability patient treated with coil embolization died of rebleeding. Four of the 21 patients treated with coil embolization required additional coils because of coil compaction.
Operative results of surgically accessible small aneurysms were satisfactory when patients were treated by selected surgeons. Therapeutic results of coil embolization for small and medium-sized aneurysms were also satisfactory. Aneurysmal neck clipping is superior to coil embolization in therapeutic radicality. Poor results cannot justify the therapeutic indication in every case with asymptomatic unruptured giant BA aneurysms.

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Aneurysmal subarachnoid hemorrhage during pregnancy is rare but is thought to be important clinically, because it might become a cause of maternal mortality. SAH from an intracranial aneurysm that has ruptured during pregnancy poses a number of questions both with respect to treatment of the aneurysm and the management of delivery. Increasing interest in these questions prompted this review, which is based on a survey of the literature. We analyzed 5 experienced cases of ruptured aneurysms in pregnancy retrospectively. SAH from an aneurysm in the 5 cases occurred during the following weeks of pregnancy: 10 weeks, 1; 32-34 weeks, 4. Among the 5 patients, there were 5 ruptured aneurysms that arose from the following arteries: internal carotid, 2; middle cerebral, 2; anterior communicating, 1. Two patients underwent delivery of fetus by cesarean section followed by aneurysmal clipping. Three patients underwent aneurysm surgery prior to cesarean section. There was no significant morbidity or mortality in the mother and fetus except 1 case who was in severe condition because of SAH. One fetus was terminated medically because SAH occurred in the early stage of pregnancy. In general, pregnant patients with ruptured aneurysms should be treated in the same fashion as those who are not pregnant, and the aneurysm should be obliterated soon after diagnosis. But if the patient's neurological grading is poor, and if aneurysm surgery is determined to be too difficult, ruptured aneurysms should be treated after cesarean section.

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We developed a method for quantitative measurement of cerebral blood flow (CBF) using multi slice dynamic computed tomography (CT) and iodinated contrast material based on the box-MTF model. We investigated whether it is possible to determine an indication for acute thrombolytic therapy using this method. Initially we examined the correlation between CBF measured by this method and that by SPECT using ^99mTC-ECD in 10 patients with chronic ischemic cerebrovascular diseases. The correlationship between them showed CBF (SPECT)=0.79×CBF (Perfusion CT) and its correlation coefficient was 0.60. To examine the reproducibility, CBF was measured twice at 5-minute intervals including 1 overlapping slice in 9 patients. The CBF value in the overlapped slice was compared between 2 examinations. Finally, the correlation between CBF and back pressure was examined in 10 patients with acute cerebral embolism. A fairly good correlation was obtained from these 2 studies. The correlation coefficient of the latter 2 studies was 0.80 and 0.86 respectively. It takes nearly 1 minute for dynamic scan, and about 15 minutes for data analysis.
This is a significant advantage for the evaluation of CBF in acute cerebrovascular disease. We conclude that our method to measure CBF using a multi slice dynamic CT scanner and box-MTF model is useful to determine the indication for acute thrombolytic therapy.

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A 71-year-old woman presented disturbance of consciousness due to subarachnoid hemorrhage (SAH). A computed tomography (CT) on admission revealed diffuse thick SAH and intracerebral hematoma in the right frontal lobe. Conventional angiography and three-dimensional CT angiography showed symmetrical aneurysms located on the bilateral pericallosal arteries at bifurcation of the callosomarginal arteries. The operation was performed on the next day after onset of SAH. The aneurysms were clipped via the right unilateral interhemispheric approach. Intraoperative findings demonstrated a ruptured right-side aneurysm adhered to a left unruptured aneurysm.
Neck clipping was performed with meticulous dissection, especially between both aneurysmal necks. Bilateral distal anterior cerebral artery (BDACA) aneurysms are rarely reported. Surgery of closely located aneurysms requires dissection of all the aneurysmal necks to secure safe and accurate obliteration. Meticulous procedures are nesesary to deal with BDACA similar to kissing aneurysms in the internal carotid artery.

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A 48-year-old woman was admitted to our emergency center for deterioration of consciousness. On arrival, her level of consciousness was 3 by the Japan Coma Scale and 10 by the Glasgow Coma Scale. Her blood pressure was 144/100 mmHg, and her pulse was regular at 136 beats/min. She was intubated under general anesthesia to lower the systolic blood pressure to 90-100 mmHg. Laboratory analysis showed elevated blood glucose (329 mg/dl), lactic dehydrogenase (311 U/l), creatinine kinase (CK, 410 U/l), and white blood cell count (19600/μl), and a reduced serum potassium (3.1 mmol/l). A computed tomographic scan showed a diffuse thick subarachnoid hemorrhage (SAH), and a chest X-ray revealed cardiomegaly and pulmonary edema. Electrocardiography on admission demonstrated sinus tachycardia and ST segment elevation in leads I, II, aVL, and V3 to V6, and a slightly prolonged QTc interval of 0.45 second. Echocardiography showed that wall motion of the left ventricular apex was significantly reduced, indicating specific “takotsubo” cardiomyopathy. Her cardiac function appeared to be well tolerant for direct surgery. Digital subtraction angiography was performed and disclosed an aneurysm at the P1 segment of the left posterior cerebral artery.
Surgical intervention was undertaken by the left pterional approach. While a subarachnoid clot in the prepontine cistern was being evacuated to expose the aneurysm via an opticocarotid triangle, her blood pressure suddenly dropped to 20 mmHg, her heart rate declined to 20 beats/min, and carotid pulsation disappeared. The surgery was discontinued and cardiac resuscitation was conducted by intravenous injection of 1 mg epinephrine and cardiac massage by chest compression. Twenty-five minutes later her cardiac function stabilized, and the aneurysm was successfully clipped. The postoperative course was uneventful, and the electrocardiogram showed inversion of T waves and gradual improvement of echocardiographic abnormalities.
An excessive catecholamine secretion related to hypothalamic damage is presumed to be the cause of cardiac dysfunction in the acute phase of SAH. Although evacuation of prepontine clot is a routine surgical maneuver, subtle compression or traction of the perforators from the P1 segment that feeds the hypothalamus might further injure the already affected hypothalamus to result in sudden cardiac arrest. In treatment of patients with SAH associated with cardiac dysfunction, preparation of an intra-aortic balloon pumping would be beneficial.

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