Deciding the best treatment of unruptured cerebral aneurysms (UA) is difficult because the natural history of UA remains uncertain. We report our experience of coil embolization for UA and discuss the safety and efficacy of coil embolization for UA. Between September 1997 and April 2004, 131 cases were treated using coil embolization in our hospital. The morbidity rate was 1.8% and the mortality rate was 0. During the follow-up period, aneurysm rupture occurred in 2 cases (14%). And 13 cases (10%) showed coil compaction, so we performed second embolizations to prevent aneurismal rupture.
The results showed that our strategy of using GDC is safe and reliable. We consider that treatment of UA requires safety first and it is important to avoid complications associated with the intervention.

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We studied problems in the treatment policies from our treatment experience with 229 cases of asymptomatic saccular unruptured cerebral aneurysm. We used clipping or coiling as needed where the aneurysm was larger than 3 mm, or was located in the dura, and the patient was younger than 70 years, had no serious general disease and had given informed consent.
Clipping was used in 170 cases. The mean age was 57.7 years. In 1 case of a high-positioned basilar tip aneurysm, clipping was considered difficult during operation, so it was changed to coiling. Surgical complications were found in 9.4% of cases (transient: 5.3%, permanent: 4.1%). Venous damage occurred in 5 cases, chronic subdural hematoma in 3 cases, memory loss in 3 cases, tight clipping in 2 cases, aggravation of existing cerebral infarction in 1 case, diminution of vision in 1 case and spasm in 1 case. There were no deaths. In the cases of multiple aneurysm, complications were found frequently when surgery was done in 1 session. Coiling was used in 16 cases. The mean age was 63.3 years. In 1 case of a relatively wide neck basilar tip aneurysm, the stability of the coil was poor, so coiling was changed to clipping. Two cases required blood transfusion or suturing of blood vessels because of hematoma at the puncture site. In 1 case, a cholesterol crystal embolism developed. Combined treatment by clipping and coiling was used in 2 cases. Neither case was problematic. Conservative treatment was used in 41 cases. The mean age was 64.3 years. Sixteen cases were treated conservatively because the patients were older than 70 years. The remaining 25 cases were younger than 70 years but were treated conservatively because the aneurysm was located extradurally (10 cases), serious medical complications were found (5 cases) or treatment was indicated but no informed consent was obtained (10 cases). The aneurysm ruptured and the patient died in 2 cases in which no informed consent was obtained.
Many of the complications in clipping are preventable, so more careful operative procedures are needed. With coiling, complications attendant upon catheterization pose problems. In 2 cases in which the conservative treatment was not given because informed consent was not obtained, the aneurysm ruptured and the patient died. A more positive attitude about obtaining informed consent on the part of neurosurgeons may be needed.

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US (Ultrasound) has become the most valuable intraoperative navigation and monitoring method. It has wide applications: monitoring blood flow, 3-dimensional angiography, tissue perfusion study by contrast sonographic imaging with PIHI, analysis of time intensity curves by (HDI lab software) and examination of their parameters. US is also simple, repeatable and harmless.
We studied the use of US as an intraoperative monitoring method on 64 patients with aneurysm. The US instrument was an HDI 5000. The linear probe was an L12-5 broad-banded type and the sector probes were a P7-4 and P4-2, respectively. The patients were examined with conventional B-mode, 3-dimensional color power angio (3DCPA) and tissue perfusion was studied by contrast sonographic imaging with PIHI.
The 3DCPA images are more effective than conventional continuous Doppler method to evaluate vascular components after aneurysmal clipping and can clearly detect vascular structures and the differences of their theories.
Perfusion examination can confirm brain tumor, venous infarction and brain damage and can detect hemorrhage at the early stage before CT and MRI diagnosis. Hereinafter, parameters of their TIC can evaluate the functional images objectively in what is called parametric imaging. The clinical application of US is becoming increasingly common.

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We retrospectively studied 55 patients with asymptomatic cerebral arteriovenous malformation (AVM) in 34 men and 21 women aged 10 to 73 years (mean 42.7 years), who underwent gamma knife radiosurgery (GKS) at our hospital. The mean nidus volume was 6.6 cc (0.1-19.6 cc), and the mean prescription dose at the nidus margin was 20.4 Gy (12-26 Gy). The actuarial obliteration rate was 65.0% at 3 years and 81.0% at 5 years, based on angiography in 22 patients and magnetic resonance (MR) imaging in 16 patients.
Multivariate analysis showed that the delivered peripheral dose significantly correlated with obliteration rate (p=0.04). Twenty-three of the 55 patients developed radiation-induced change of brain tissue on follow-up MR imaging, and 6 of the 23 patients were symptomatic. Fourteen of 23 patients with edema of the brain tissue required steroid therapy. There was no permanent neurological complication. One of the 55 patients suffered postradiosurgical hemorrhage. No patient developed long-term complication such as cyst formation or chronic encapsulated expanding hematoma.
These findings suggest that GKS is effective for the treatment of asymptomatic cerebral AVM, especially if located in deep or eloquent areas. In contrast, we recommend direct surgery for AVM in surgically accessible regions because of the relatively high rate of radiation-induced change of brain tissue on follow-up MR imaging.

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After the publication of ISAT trial, intraaneurysmal coil embolization has become more widely used for treatment of aneurysm. There are, however, some disadvantages in intraaneurysmal coil embolization. One is how to treat wide neck aneurysm. Among several solutions, such as 3D coils and double catheter technique, neck plasty technique is the most effective method at present.
A new balloon catheter, HyperForm balloon occlusion system (HyperForm), for neck plasty technique has recently been developed. This balloon, with a maximum diameter of 7 mm, is so soft that it is called supercompliant. We report our experiences using the balloon.
The cases in this study were 13 aneurysms in 12 patients in whom intraaneurysmal coil embolization was performed using HyperForm. The site of the aneurysm was internal carotid artery (ICA) in 6, basilar bifurcation in 5, and middle cerebral artery (MCA) in 2. The procedure itself is similar to ordinary neck plasty method. Most different fashion is in the situation of basilar bifurcation aneurysm. Many basilar bifurcation aneurysms dominantly saddle one of the posterior cerebral arteries (PCAs). We usually try to navigate a neck plasty balloon through the PCA that is saddled more by aneurysm. However, during this procedure the guidewire tends to migrate inside the aneurysm. In other words, the less important it is to preserve the PCA, the easier it is to canulate. HyperForm inflates irregularly as if the balloon itself is searching for space. Thanks to this characteristic of HyperForm, the important PCA can be protected even as the HyperForm is navigated through the less important PCA.
Therefore, HyperForm is very useful for intraaneurysmal embolization of basilar bifurcation aneurysm. Another possible advantage of HyperForm is its larger diameter. The largest diameter of the previously used balloon was 4.5 mm, but HyperForm has a maximum diameter of 7 mm, which is useful for ICA aneurysm. However, because of its softness, HyperForm tends to jump during treatment of ICA aneurysm. There were 2 complications in this series. Both were perforations by the guide wire, one was aneurysm and the other was perforator, in the treatment of MCA aneurysm.
In conclusion, HyperForm is very useful for neck plasty technique, especially in treatment of wide neck basilar bifurcation aneurysm.

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Nicardipine prolonged-release pellets (NP) are made for implantation during surgery to prevent cerebral vasospasm. We retrospectively analyzed patients with a poor-grade subarachnoid hemorrhage (SAH) between October 1999 and September 2004. Among 125 surgically treated SAH patients, 34 belonged to WFNS grades 4 and 5 (male/female 13/21, the average age was 63, the ratio craniotomy/coil 26/8). Four to 12 NPs (16-48 mg of nicardipine) were placed along the respective artery (IC, A1, A2, A3, M1, M2, and M3) after clipping the aneurysm, where there was thick clot and therefore subsequent vasospasm was highly likely.
The intracranial pressure was monitored and treated with glycerin, ventricular drainage, external decompression, and/or barbiturate administration. Neither induced hypervolemia nor induced hypertension was used. A delayed ischemic neurological deficit was seen in 1 patient, but there were no cerebral infarctions due to cerebral vasospasm. Angiography performed on days 7-12 revealed no vasospasm in any arteries close to where the NPs were placed. The outcome after 3 months was good in 7, moderately disabled in 13, severely disabled in 7, vegetative state in 2, and 5 patients had deceased.
The NP is an effective, simple, and safe prophylactic treatment to prevent vasospasm when a surgical procedure is chosen to treat ruptured aneurysms of poor-grade SAH patients.

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We analyzed the incidence of vasospasm (VS) of the cerebral arteries in the patients treated with coil embolization using Guglielmi detachable coils (GDCs) for ruptured cerebral aneurysms, and herein we report the details.
Between March 1997 and March 2005, 52 patients underwent coil embolization within 7 days following rupture of cerebral aneurysms. We excluded 8 patients in whom VS could not be judged due to prolonged disturbance of consciousness resulting from early brain damage consequent to subarachnoid hemorrhage (SAH); early mortality; or other causes, as well as 2 patients in whom VS was already detected at the time of coil embolization. The remaining 42 patients (mean age: 64.4 years) were the subjects of our study. When thick hematomas were revealed on CT scans, spinal drainage was placed until SAH disappeared, while 3H therapy was actively conducted if the patients showed any manifestations of VS. In addition, when no improvement could be achieved, intra-arterial injection of papaverine hydrochloride was administered or (simultaneous) vascular reconstruction was performed.
Preoperatively, H & H grade was I in 1 case, II in 16 cases, III in 6 cases, IV in 17 cases, and V in 2 cases. In the Fisher CT group, the grade was 1 in 1 case, 2 in 13 cases, 3 in 25 cases, and 4 in 3 cases. In 11 of the 42 patients (26.2%), cerebral VS was noticed, and the manifestations such as hemiplegia persisted in 3 (7.1%).
The incidence of symptomatic cerebral VS following craniotomy is reportedly about 15% to 30%, but in our present study we found that the incidence was relatively slightly lower following coil embolization. Our results suggest that comparative studies on post-craniotomy cerebral VS should be conducted.

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Symptomatic vasospasm (SVS) can occur after subarachnoid hemorrhage (SAH) and has been considered as a factor associated with negative prognosis in SAH. However, no standard method for preventing SVS is currently available. Various preventive methods have thus been developed and conducted in each institution. To obtain a standardized preventive method for SVS after SAH, the present multi-institutional cooperative clinical study of fasudil hydrochloride was conducted in 5 institutions in Kanagawa Prefecture.
Subjects comprised 112 SAH patients <75-years-old who were admitted to 5 institutions in Kanagawa Prefecture between October 2000 and May 2004, and who underwent clipping of cerebral aneurysms during the acute stage. Subjects were randomly categorized into 3 groups, to receive: fasudil hydrochloride (Fa, n=57); nicardipine hydrochloride (Ni, n=32); or ozagrel sodium (Oz, n=23). Patients were provided with each assigned treatment immediately after the operation. Degree of vasospasm (AVS) observed on cerebral angiography 1 week after onset of SAH, frequency of SVS, and treatment results after 1 and 3 months according to the Glasgow Outcome Scale (GOS) were examined.
Frequency of AVS at 1 week after onset of SAH was 56% in all subjects, with 81% for Oz, 55% for Fa and 41% for Ni. A significant difference was observed between Oz and the other treatment groups. Frequency of SVS for all subjects was 22%, with 23% for Fa, 13% for Ni and 35% for Oz. A significant difference was noted between Ni and Oz groups. In the evaluation of Glasgow outcome scale (GOS) after 3 months, good recovery (GR) was achieved by 64% of all subjects, with 70% for Fa, 68% for Ni and 48% for Oz. A significant difference was identified between Fa and Oz groups.
Fasudil hydrochloride is recommended for use as a standard therapeutic drug in SAH treatment.

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We experienced 17 patients with unruptured arteriovenous malformation (AVM) in our department. Eight patients presented with epileptic seizure and 9 cases were diagnosed incidentally. Management strategies were as follows: extirpation following embolization in 3, extirpation alone in 2, stereotactic radiosurgery (SRS) alone in 3, SRS following embolization in 1 while no treatment was given on 8 patients based on informed consent. The mean follow-up period was 55.1 months.
Disappearance of the lesion was confirmed in 8 of 9 patient with some treatment. In the group, there was no mortality. The 2 morbidities involved postoperative epidural abscess and epilepsy in 1, and transient hemiparesis and motor aphasia following embolization in the other. No hemorrhage was reported in patients with no treatment during the follow-up period. One patient with a frontal AVM has been bothered by intractable seizures in reaction to anticonvulsant medication.
Reviewing the literatures, the mean risk of bleeding of the unruptured AVMs is 1 to 3% per year, while factors predicting hemorrhage are controversial. The prescribed treatment, nonetheless, should be defined from an objective assessment of what is optimal for each individual patient as well as from local expertise.

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Generally vitreous hemorrhage (VH) is detected in 2.2% to 13% of subarachnoid hemorrhage (SAH) patients. VH with SAH (Terson's syndrome) is known to occur frequently in patients with severe SAH or re-ruptured aneurysms. We retrospectively analyzed 20 patients diagnosed with Terson's syndrome out of a total of 881 patients treated for SAH in our department from July 1995 to October 2004. Our study group comprised 15 male and 5 female patients ranging in age from 38 to 77 years (mean 51.2 years). Each patient was classified in Hunt & Kosnik (H&K) grades on admission. One patient was classified in Grade 2, 3 patients in Grade 3, 7 patients in Grade 4 and 9 patients in Grade 5. Each patient was further classified in a Fisher group: 1 patient was in Group 2, 9 patients in Group 3, and 10 patients in Group 4. Regarding the aneurysmal location, 4 cases had ICA aneurysms, 6 had AcomA aneurysms, 4 had MCA aneurysms, 4 had VA or BA aneurysms, and 2 had ACA aneurysms. Re-rupture of aneurysm occurred in 4 cases. Two patients underwent external ventricular drainage because of acute hydrocephalus immediately after CT on admission.
Seventeen aneurysms were treated by surgical neck clipping, and 3 aneurysms were treated by intra-aneurysmal coil embolization as the final treatment. Seven patients underwent external decompression because of severe brain swelling, and 6 patients underwent V-P shunt for chronic hydrocephalus. Symptomatic vasospasm occurred in 1 case. Glasgow Outcome Scale (GOS) at discharge showed that 8 patients were GR, 10 were MD, and 2 were SD. VH occurred in only 1 patient on the contralateral side to the ruptured aneurysm among those who had obvious hemilateral VH. Vitrectomy was performed for the 17 VH of 10 patients, and the duration from VH onset to treatment was 8-24 weeks (mean 16.4 weeks). Conservative therapy was done for 15 VH of 10 patients, and the follow-up duration was 12-102 weeks (mean 27.0 weeks).
Comparing these 20 VH patients with 311 favorable-outcome (GR or MD) patients who were not considered to have VH, H&K grade or Fisher group scales were significantly higher in VH patients. No significant difference existed between the groups with regard to the number of ruptures or the location of the ruptured aneurysms.

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Recent studies have shown that percutaneous transluminal angioplasty (PTA) of vertebral artery origin stenosis (VAS) is safe and effective. On the other hand, a major concern about the procedure involves the risk of embolic phenomena. But there have been no studies detecting debris during the PTA of VAS. We reviewed 20 patients to examine the distal embolism of debris caused by the procedure.
Twenty patients (2 female, 18 male) with a mean age of 65.3 years (range 49 to 78 years) underwent treatment with the PTA of VAS. Among 20 cases, a protection device was used in 11 cases (distal protection: 7 cases, proximal protection: 4 cases). In the distal protective balloon technique, the protective balloon was set so as to occlude the stenotic artery distally. In this technique, we sucked up the blockaded blood that was likely to contain debris and confirmed existence of debris. In the proximal protective technique, the protective balloon was set so as to occlude the proximal subclavian artery.
In all 20 cases, there was no ischemic event during the procedure. In 6 of 7 cases with distal protection, micro debris could be found in blood samples.
Our report clearly shows for the first time that debris is often induced by PTA of VAS, and protection device works effectively during the procedure. Safer PTA can be performed using a protective device.

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