Spinal arteriovenous malformation (spinal AVM) is a rare but clinically important disease in that it presents with progressive, somewhat stepwise worsening myelopathy, and its outcome of natural course is very poor.
Classification of spinal AVM based on angiographical features has been very difficult to understand, and we propose here a comprehensive one based upon the sites of A-V shunts. For diagnostic purposes, MRI gives us not only the location of AVM but also the existence of venous congestion in the spinal cord itself. But selective spinal angiography still remains the gold standard for confirming the shunt points and planning the strategy of treatment.
Both surgical and endovascular interventions are available for its treatment, and we detail all the surgical treatment procedures. The lateral oblique position reduces the risk of venous hypertension during surgery and is also comfortable for the operator. Using microdoppler monitoring with meticulous temporary clipping is somewhat laborious but the best method for understanding the complex vasculature as well as accurately implementing treatment.
What is most essential is that the total extirpation of abnormal A-V shunts be realized for this disease to achieve total cure. The treatment strategy should be based on this point, and palliative therapy, which would produce a more complicated condition afterwards, should be avoided.

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To determine the indication for surgical management in poor-grade aneurysm patients, we analyzed 1095 patients with World Federation of Neurological Societies (WFNS) Grade IV/V aneurysm admitted within 48 hours after subarachnoid hemorrhage (SAH) between Jan. 1989 and Dec. 2000, retrospectively. Nineteen patients who were operated on between Day 4 and Day 9 and 16 patients who underwent coil embolization were excluded from this study. There were 397 patients aged <60 years, 327 patients aged 60-69 years, and 336 patients aged ≥70 years. Surgical treatment was done between Day 0 and Day 3 in 678 patients (early surgery (ES)), Day 10 or beyond in 164 patients (late surgery (LS)); 218 patients did not undergo surgical management. The latter 2 groups of patients were designated non-early surgery (non-ES).
The outcome was evaluated with GOS at 3 months after SAH. Rebleeding developed in 56 patients within 24 hours of admission and in 47 patients 24 hours after admission. It was difficult to assign patients with rebleeding within 24 hours to ES or non-ES. These patients were, therefore, excluded from ES and non-ES and designated early management group (EMG) and non-early management group (non-EMG), respectively. In the analysis of Grade IV, 47.9% of ES and 50% of LS in the <60 years age group showed Good Recovery (GR). In contrast, the proportions of GR were 49.5% in EMG and 35.2% in non-EMG (P=0.0345). Among the 60-69 years age group, the rates of GR were 26.9% and 35.3% in ES and LS, respectively; and 28.0% and 24.0% in EMG and non-EMG, respectively. Among the ≥70 years age group, the incidence of GR was 10.1% and 14.6% in ES and LS, respectively; and 10.6% and 8.4% in EMG and on-EMG, respectively.
Regarding the Grade V, among the <60 years age group, only 10.6% of ES resulted in GR. Although the incidence of GR was not statistically different between ES and LS, 25.0% of LS showed GR. The incidence of GR was 9.8% and 10.9% in EMG and non-EMG, respectively. Among the 60-69 years age group, the proportions of GR were 12.2% and 17.6% in ES and LS, respectively; 11.8% and 6.0% in EMG and non-EMG, respectively. Among the ≥70 years age group, only 1.3% of ES and 1.3% of EMG showed GR. No patients showed GR in LS or non-EMG. The outcome of LS was possibly better than that of ES because some patients who did not recover well in the late stage had less chance to undergo surgery. In contrast, EMG might show better results than non-EMG because patients in non-EMG often presented in poor general condition, contraindicating surgery.
Considering these 2 possibilities, we conclude that early surgery benefits patients aged <60 years with Grade IV. Late surgery following good response from conservative therapy is suggested in patients with Grade IV and aged <70years and the≥70years age group of Grade IV.

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Indication of early treatment remains controversial for patients in poor clinical condition (Hunt & Kosnik Grade 4 or 5) after subarachnoid hemorrhage (SAH). Since 1997, we have adopted endovascular treatment using Guglielmi detachable coil (GDC) as a treatment option for these patients. In this study, we compared clinical courses of the cases treated in 1990-1996 to those treated in 1997-2002 to evaluate the efficacy of changes in treatment strategy.
Between 1990 and 2002, 130 cases with SAH in Grade 4 and 5 underwent angiography as candidates of early aggressive treatment in our hospital. For the 63 cases in 1990-96 (Group 1), treatment options were early and intensively delayed craniotomy surgery and conservative management, while for the 67 cases in 1997-2002 (Group 2), GDC embolization at acute stage was added to these 3 treatment options. We compared the 2 groups of patients in terms of clinical courses and outcomes, assessed with Glasgow Outcome Scale Score (GOS) at discharge.
The percentage of the patients in which aneurysm was occluded at acute stage increased from 67% in Group 1 to 87% in Group 2 for Grade 4 and from 33% to 52% for Grade 5. In Group 2, 44% of Grade 4 and 83% of Grade 5 patients were treated by GDC embolization. The outcomes of the cases in both Grade 4 and 5 were better in Group 2 than in Group 1. That is, for Grade 4 cases, the percentage of Good Recovery (GR) significantly increased from 7% in Group 1 to 27% in Group 2. And for Grade 5 cases, good outcome (GR or MD) increased from 5% in Group 1 to 18% in Group 2. Two patients recovered completely from Grade 5 in Group 2, both of which were treated with GDC while none in Group 1 recovered completely from Grade 5. The incidence of symptomatic vasospasm was not changed between Group 1 (20%) and Group 2 (16%).
The introduction of GDC embolization extended the indication of early treatment for severe SAH patients because it was less invasive and, as a consequence, improved the outcome of those patients.

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The pterional approach includes 2 major approaches: the subfrontal and transsylvian approach. Both approaches are popular operative techniques in neurosurgery. We describe a distal transsylvian approach to internal carotid artery aneurysm that includes the following components: 1) beginning the dissection of sylvian fissure at 5 cm distal from temporal tip, 2) identifying the M3 and/or M2 portion of middle cerebral artery in the insular cistern, 3) cutting arachnoid trabeculle between frontal lobe and temporal lobe from deep area to the surface of sylvian fissure, 4) preserving associating veins along sylvian fissure in order to prevent venous infarction after surgery, and 5) using the extended approach of distal transsylvian approach, which is called the anterior temporal approach.
This method results in enhanced exposure with preservation of sylvian veins and minimal retraction of brain. Especially thick subarachnoid blood clots can be evacuated well in the distal sylvian fissure such as the “Sylvian Point” on angiogram. In cases of posterior projected IC-PC aneurysm, the distal transsylvian approach can be converted to the anterior temporal approach, in which it is easy to recognize perforators arising posterior to the communicating artery.
This procedure can serve as an alternative to subfrontal approach for subarachnoid hemorrhage or complex IC-PC aneurysms.

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We report on 5 intracranial atherosclerotic stenoses treated with stent-assisted angioplasty. All lesions except for a stenosis that the stent was not able to access due to a severe tortuousity of the vessel were sufficiently and smoothly dilated with the use of a highly flexible, balloon-expandable coronary stent. All symptoms caused by the stenoses disappeared or diminished after the treatment. No complications occurred during or after the procedure. Follow-up angiograms obtained 6 months after the stenting showed no remarkable restenosis.
This therapeutic option is a useful treatment for intracranial artery stenosis although further study, including clinical long-term follow-up, is necessary.

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Hyponatremia after subarachnoid hemorrhage (SAH) is considered to correlate with salt wasting syndrome. The exact mechanism is still not understood, but brain natriuretic peptide (BNP) and atrial natriuretic peptide (ANP) have been suspected as main factors. In the past few years, fludrocortisone has been advocated to inhibit natiruretics after SAH.
We examined BNP and ANP level at 2 different time periods (3 to 7 days, and 9 to 15 days) in 14 patients with spontaneous SAH. Patients were divided into 2 groups: controls (6 patients) and patients treated with fludrocortisone (8 patients). Without fludrocortisone all patients tended to develop hyponatremia, but with fludrocortisone most patients had normonatremia. In the former group, BNP were increased, but in the latter group both BNP and ANP level were decreased during the sub-acute stage except for hyponatremic cases. Fludrocortisone was effective to control salt loss, and may suppress BNP.
BNP is thought to be responsible for natriuresis. Therapeutic overhydration might cause an increase of both BNP and ANP.

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Carotid artery stenting (CAS) has emerged as an endovascular treatment for obstructive extracranial carotid artery disease. Despite advanced stenting techniques, neurological events linked to embolization of the particulate material in cerebral circulation occur in 5% of cases. A distal balloon protection system is increasingly being used to prevent cerebral atheroembolism during CAS procedures. In this study, we examined the possible beneficial effect of a new cerebral protection device (PercuSurge occlusion balloon) based on balloon occlusion of the distal internal carotid artery (ICA) and debris aspiration for patients undergoing postdilation.
Eight patients underwent CAS using the PercuSurge GuardWire system. SMART stents were employed after predilation. The protective balloon was then introduced into the carotid artery, and advanced across the lesion. After postdilation, the PercuSurge Export aspiration catheter with proximal vacuum syringe was advanced toward the occlusion balloon. With suction applied, this catheter was advanced and retracted several times. In the 8 patients, the mean stenosis rate before stenting, 82.6%, markedly decreased to 8.8% after the procedure. The debris containing atheromatous emboli was removed by aspiration. On diffusion-weighted MRI, hyperintense areas were detected in 3 of the 8 patients. No complication related to the procedures occurred.
Stenting with the PercuSurge GuardWire system for cervical ICA stenosis is an effective therapeutic modality. Protection devices may play an important role in future carotid interventions and expand the applicability of the procedure.

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We evaluated three-dimensional MR angiography (3D-MRA) for the diagnosis and treatment of ruptured cerebral aneurysms. During the past 5 years, 46 patients with subarachnoid hemorrhage (SAH) from cerebral aneurysms were operated on in our hospital. MRI FLAIR image was very useful for the diagnosis of SAH, especially in a subacute stage.
Of the 46 patients, 1 patient was examined by conventional angiography due to the past history with non-titanium clip placement after SAH. Three patients were examined both by 3D-MRA and conventional angiography, and 42 patients were studied using 3D-MRA without conventional angiography. Conventional angiography was necessary after 3D-MRA because of the existence of 1 distal anterior cerebral artery aneurysm, 1 distal anterior inferior cerebellar artery aneurysm and 1 thrombosed anterior communicating artery aneurysm. Forty-two aneurysms, including 8 associated unruptured cerebral aneurysms, were visualized by 3D-MRA and verified at surgery. All aneurysms were clipped or wrapped successfully.
3D-MRA is a noninvasive tool that does not require contrast media and has enabled a more accurate diagnosis of cerebral aneurysm by developing three-dimensional image reconstruction. We consider that it will be possible to operate on most ruptured cerebral aneurysms using only 3D-MRA without conventional angiography except for special cases, such as peripheral aneurysm, dissecting aneurysm, and large or giant aneurysm.

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The problem of early thrombosis-occlusion and recurrent carotid artery stenosis has raised a controversy over whether primary closure or patch graft closure is better. In 17 patients treated by CEA between 1998 and 2002, patch grafts were used in our institute to avoid acute thrombosis-occlusion and restenosis. In this study, we investigated the following: surgical complications, ischemic events in the follow-up term and restenosis in the follow-up term.
No surgical complications developed. During the follow-up term (26.2±16.7, no patient showed any ischemic symptoms. In 15 patients, follow-up angiography was performed. The mean follow-up was 15.0±17.0 months. On follow-up angiography, no patient showed restenosis of more than 50%.
We suggest endarterectomy with patch graft as an effective treatment of atherosclerotic carotid stenosis.

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Although the treatment of SAH has been much improved recently, the prognosis in elderly patients remains poor due to problems related to the aging. In order to consider future strategy to improve treatment results, it is important to know the character of SAH specific to elderly patients. The clinical features in 65 SAH patients aged between 70 and 88 years, treated between 1997 and 2002, were investigated. The results of clipping in the acute stage were analyzed in relation to tolerability to the active treatments in elderly patients.
The effect of operation in the acute stage showed remarkable contrast in each group of clinical condition: in the severe group only 16% in their 70s and 0% in their 80s showed good recovery but in the mild group it was 84% in those in their 70s and 83% in those in their 80s, which was comparable to the outcome in younger patients. The clinical condition in patients with poor outcome was characterized by the presentation of disturbance in higher cortical function, indicating the presence of generalized damage in the brain in elderly patients.
SAH in elderly patients is characterized clinically by distinction of 2 groups: one in which the effect of SAH easily resulted in generalized brain damage and the other in which patients could withstand the effect of SAH. The latter group can be treated aggressively. For the former group, treatments consisting of palliative measures such as embolization and meticulous general care are essential.

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Aneurysms of the distal anterior inferior cerebellar artery (AICA) are very rare, occurring in 0.03-0.5% of cerebral aneurysms. We report 2 cases of distal AICA aneurysms at the internal auditory meatus.
In 1 of them, the whole aneurysm was located in the internal acoustic meatus. Such an aneurysm is called an intrameatal aneurysm, which is an extremely rare type of distal AICA aneurysm with only 7 cases reported in the literature.
Both of our patients presented with subarachnoid hemorrhage and were treated with early clipping surgery via the lateral suboccipital approach. The clipping was successful and they recovered uneventfully, but continued to have a hearing loss.
We provide a review of the literature and a discussion of possible causes of 8th cranial nerve impairment in distal AICA aneurysms.

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