Less invasive technique for EC-IC bypass.

BACKGROUND: We introduce less invasive technique for superficial temporal to middle cerebral artery (STA-MCA) anastomosis, and also described an innovative technique to preoperatively identify the recipient artery using three dimensional CT angiography (3D CTA). Objective. In a period of 28 months between January 2004 and April 2006, 39 EC-IC bypass were performed for hemodynamic compromised patients (including 9 patients with Moyamoya disease) using less invasive technique. METHODS: Operative technique is as follows: 1) A parietal or frontal branch of STA and cortical arteries could be identified on the original images of 3D CTA. The most suitable segment of both the artery provided as donor and recipient arteries for EC-IC bypass. The distance between the afore-mentioned segment of donor artery (STA) and the superior border of the helix were calculated. 2) A 5 cm linear skin incision on the STA, the center of which was the point measured on preoperative 3D CTA, was made. The temporal muscle was divided in the same fashion, and a 3 cm small craniotomy was made. The recipient artery could be identified on the center of the craniotomy. End-to-side anastomosis was performed in the usual way. RESULTS: Operation times were 115-172 min (mean 154 min) and intraoperative blood loss was 20-60 ml (mean 38 ml). All bypasses were patent on the post-operative 3D CTA. CONCLUSIONS: This technique for EC-IC bypass was less invasive and cosmetically excellent. 3D CTA provides useful information for planning of the less invasive EC-IC bypass.

Treatment of cerebral aneurysms: surgical clipping and coil embolization.

SUMMARY: The present series provides a balanced overview of the treatment of aneurysms in surgical clipping and coil embolization. Between January 2004 and March 2006, 76 consecutive patients with cerebral aneurysms underwent endovascular embolization and/or surgical clipping. Of these, 42 patients suffered an aneurysmal subarachnoid hemorrhage (SAH), while the remaining 34 patients had nonruptured cerebral aneurysms. Of the 23 surgically treated patients, 17 (73.9%) achieved a favorable outcome. Of the 19 patients who underwent endovascular embolization, 12 (63.2%) achieved a favorable outcome. Three patients (15.8%) who underwent endovascular embolization needed to undergo re-treatments, while no re-treatment was needed in the surgically treated patients. Of the 34 nonruptured aneurysms, 12 (35.3%) were treated using surgical clipping, while 22 (64.7%) underwent endovascular embolization. The complication rates of the two treatment modalities demonstrated no significant difference. A combined microsurgical-endovascular team approach is thus considered to provide the most effective means to achieve favorable outcomes for patients with cerebral aneurysms.

Strategy for Prevention of Restenosis after PTA. Clinical and Basic Approaches.

SUMMARY: Percutaneous transluminal angioplasty (PTA) has been a useful therapy to treat stenosis of cervical internal carotid artery (ICA) or vertebral artery (VA). Here we show that our clinical results regarding preventive effect of stenting on restenosis after PTA in the ICA and VA origin. We also show our experimental studies with gene transfer techniques aiming reduction of restenosis after balloon-injury in rat carotid artery. It has been reported that drug-eluting stent inhibits restenosis after coronary angioplasty. Further understanding of the mechanism of restenosis and application of these new modalities may lead to better clinical results in angioplasty of the craniocervical arteries.

Clinical and Angiographic Results of Intra-Aneurysmal Embolization for Cerebral Aneurysms and Histopathological Findings in an Aneurysm Treated with GDC.

SUMMARY: We describe follow-up clinical and angiographic results in patients with cerebral aneurysms treated with IDC or GDC. In 175 patients, 116 patients with ruptured aneurysm and 59 patients with non-ruptured aneurysm who underwent endovascular occlusion of aneurysms, there was no mortality and nine cases (4.7%) with morbidity in the periprocedural period. During follow up period, four cases (2.3%) experienced bleeding, and three cases (1.7%) experienced thrombo-embolic events. On the follow-up angiograms (median angiographic follow-up period 24.8 months), 12.5% of incompletely obliterated aneurysms exhibited progressive thrombosis, 20% remained unchanged and 67.5% showed aneurysmal recanalization or regrowth. Histological examination of a small ruptured A-com aneurysm treated seven months before harvesting, demonstrated that formation of an incomplete endothelium- lined layer of connective tissue at the orifice, and no complete fibrous obliteration of the aneurysm lumen could be detected, various amounts of unorganized clot were still present in the center of the aneurysm. Coil embolization is a safe treatment for cerebral aneurysms with a lower incidence of peri-procedural morbidity, wheareas follow-up results are less satisfactory in cases involving incompletely obliterated lesions.

Embolic Complications of Endovascular Surgery for Cerebrovascular Diseases. Evaluation with Diffusion-Weighted MR Imaging.

SUMMARY: The purpose of this study was to evaluate asymptomatic embolisms during cerebral endovascular surgery for cerebrovascular diseases with diffusion-weighted magnetic resonance imaging (DWI) which allowed sensitive and early detection of cerebral ischemic lesions. 71 patients who underwent a total of 74 cerebral endovascular procedures were subjected to DWI screening study. MR imaging was performed on a 1.5T system by using single-shot SE echo-planar imaging (EPI) with b value of 1100 seconds per mm(2) in pre- and post-treatment periods (between day 2 and 5 after procedures). In 38 (51.3%) of 74 procedures, new high intensity lesions, as recent infarctions related to procedures, were detected on post-procedural DWI. In 18 Of the patients (47.4%), symptomatic infarctions occurred and resulted in TIAs (n = 4), RINDs (n = 8), minor strokes (n = 6) and no major strokes and no death. 20 (52.6%) of the recent infarctions detected by DWI were asymptomatic lesions.Most of the asymptomatic ischemic lesions were likely to be distributed in watershed border areas. On the other hand, symptomatic lesions tended to be distributed in cortical and/or perforator regions and to be multiple. Thus, DWI is a useful method that can detect neurologically silent and asymptomatic ischemic lesions. It can be used to help to evaluate the safety and efficacy of neurovascular intervention.

[Endovascular surgery for untreated ruptured aneurysm with symptomatic vasospasm].

It is difficult to treat ruptured aneurysms with symptomatic vasospasm. Although direct surgery for such cases is associated with poor outcomes, conservative therapy has the risk of both rerupture and infarction. In two cases of ruptured aneurysms with symptomatic vasospasm, we performed aneurysmal coil embolization with Guglielmi electrodetatchable coils (GDC). At the same time we performed percutaneous transluminal angioplasty (PTA) with papaverine infusion. In both cases, rerupture did not occur and PTA was effective angiographically. A good outcome was achieved in case 1. However, broad cerebral infarction occurred in case 2, in which the patient had shown severe symptomatic vasospasm on admission. In advanced cases, such as in case 2, the outcome is poor. The aneurysm may not be able to be approached before PTA because of severe vasospasm. In such cases, PTA must be performed carefully to avoid aneurysmal rerupture. Intraarterial papaverine infusion is safer than PTA for severe spasm in distal vessels. However the efficacy of papaverine is known to be transient in many cases. It is often difficult to determine the exact relationship between branches and the aneurysm in the presence of vasospasm. In such cases, we recommend that the rupture point be packed and that the aneurysmal neck remain unpacked. After vasospasm is cured and good general condition has been recovered, direct surgery can be performed. In summary, endovascular surgery is an effective option for treatment of ruptured aneurysm with symptomatic vasospasm.

Magnetic resonance imaging of acute cerebellar ataxia: report of a case with gadolinium enhancement and review of the literature.

A 10-year-old girl exhibited severe cerebellar ataxia following acute enterocolitis, and was diagnosed as having acute cerebellar ataxia (ACA). MRI of the brain in the acute stage revealed moderate swelling of the cerebellum and abnormal signal intensity enhanced with gadolinium in the cerebellar hemisphere. This is the first report of an ACA case with positive gadolinium enhancement. Cases of ACA with MRI abnormalities are reviewed and the clinical entity of ACA is discussed in association with autoimmune encephalitis.

Arteriovenous malformation in association with moyamoya disease. Report of two cases.

The authors report two rare cases of arteriovenous malformation (AVM) associated with moyamoya disease. An AVM, supplied by transdural communicating arteries, was located in the right occipital lobe in one patient who presented with ischemia. The second AVM, which was supplied by basal moyamoya vessels, was located in the posterior part of the left frontal lobe in a patient who developed intracerebral hemorrhage that occupied the left basal ganglion. A review of the literature revealed a total of 12 AVMs in 11 patients with moyamoya disease including our cases. All AVMs were cerebral and two were supplied by normal cerebral arteries, whereas six AVMs were supplied by basal moyamoya vessels at the base of the brain and four AVMs were supplied by external carotid arteries through the transdural communicating arteries. Every AVM drained into deep or cortical cerebral veins. These findings suggest that the hyperangiogenic character of moyamoya disease occasionally induces the development of acquired arteriovenous shunts that mimic AVM.