OBJECTIVE: The goal of this study was to compare several parameters, including wall shear stress (WSS) and flow pattern, between unruptured and ruptured anterior communicating artery (ACoA) aneurysms using patient-specific aneurysm geometry.METHODS: In total, 18 unruptured and 24 ruptured aneurysms were analyzed using computational fluid dynamics (CFD) models. Minimal, average, and maximal wall shear stress were calculated based on CFD simulations. Aneurysm height, ostium diameter, aspect ratio, and area of aneurysm were measured. Aneurysms were classified according to flow complexity (simple or complex) and inflow jet (concentrated or diffused). Statistical analyses were performed to ascertain differences between the aneurysm groups.RESULTS: Average wall shear stress of the ruptured group was greater than that of the unruptured group (9.42% for aneurysm and 10.38% for ostium). The average area of ruptured aneurysms was 31.22% larger than unruptured aneurysms. Simple flow was observed in 14 of 18 (78%) unruptured aneurysms, while all ruptured aneurysms had complex flow (p < 0.001). Ruptured aneurysms were more likely to have a concentrated inflow jet (63%), while unruptured aneurysms predominantly had a diffused inflow jet (83%, p=0.004).CONCLUSION: Ruptured aneurysms tended to have a larger geometric size and greater WSS compared to unruptured aneurysms, but the difference was not statistically significant. Flow complexity and inflow jet were significantly different between unruptured and ruptured ACoA aneurysms.
Aneurysm ; Aneurysm, Ruptured ; Arteries ; Hydrodynamics ; Intracranial Aneurysm

A retrospective study on 14 case of ruptured cerebral cranial carotid aneurysm operated in Viet Duc Hospital during 1998 - 2000 has shown that the clinical outcome and method of operation found well in 78.6% of patients. The time for operation was usually late (often 2-3 weeks of bleeding).
Aneurysm, Ruptured ; Cerebral Arterial Diseases

In an attempt to decide the surgical approach to basilar tip aneurysms, 27 cases of ruptured aneurysms were retrospectively analysed for size of aneurysm, direction of fundus and height of bifurcation. The fundus pointed superiorly in 18 cases, posteriorly in six, and anteriorly in three. The aneurysm neck was positioned as follows : very high(more than 20mm above midsellar) in one case, high(between 10mm and 20mm above midsellar) in 13, mid(from midsellar to 10mm above it) in nine, low(from midsellar to sellar floor) in two, and very low(below the sellar floor) in two. In 11 cases, surgery followed the conventional pterional approach ; in eight, the orbitozygomatic ; in three, the pterional-anterior temporal ; in two, the subtemporal ; in two, the anterior transpetrosal ; and in one, the temporopolar. In complex aneurysms or basilar bifurcation was at an unusual height, surgery involved a skull-base or modified technique based on a conventional pterional and subtemporal approach. On the basic of our surgical data and related findings, our suggestious are as follows : surgery involving basilar tip aneurysms with an extremely high-positioned neck should follow the transsylvian route above the carotid bifurcation, or use a transventricular or intravascular approach ; in cases with a high positioned-neck, the orbitozygomatic temporopolar or transzygomatic subtemporal approach should be used ; in cases with a normal-positioned neck, the combined pterional-anterior temporal approach, which has a much wider operative field and wider angle of vision than the classic pterional and subtemporal approach ; in cases with a low-positioned neck, the subtemporaltranstentorial) pterional, with resection of the posterior clinoid process ; and in cases with a very low-positioned neck, the transpetrosal approach.
Aneurysm* ; Aneurysm, Ruptured ; Neck ; Retrospective Studies

No abstract available.
Aneurysm ; Aneurysm, Ruptured* ; Cerebral Veins* ; Veins*

Fenestrations of anterior cerebral arteries are rare anomalies, which may be associated with saccular aneurysms at the fenestration itself or other intracranial vessels. This association is not infrequently the cause of angiographic diagnostic problem, as well as surgical difficulties. We report a case of aneurysm arising from a fenestrated proximal anterior cerebral artery that was confirmed at surgery and discuss together with a review of the literature.
Aneurysm ; Aneurysm, Ruptured* ; Anterior Cerebral Artery*

The purpose of this study was to investigate whether early surgery benefits in the treatment of the patients with ruptured aneurysm by comparing the outcome in relation to the timing of surgery. The autho rs analyzed 81 patients with ruptured aneurysm who underwent operation during one year from January 1996 through December 1996. Among these, sixty patients(74%) underwent operation within 72 hours after first bleeding, and 21 patients (26%) after 72 hours following first bleeding. Thirtysix patients(82%) recovered without se rious neurological deficits in 44 patients with initial Hunt and Hess g rade I to III who were operated upon in early period, and four out of 16 patients with initial Hunt and Hess grade IV to V. Sixteen patients (84%) recovered without serious neurological deficits in 19 patients with initial Hunt and Hess grade I to III who received late operation but none in 2 patients in Hunt and Hess grade IV to V. Seven out of 60 (12%) patients died after early operation, one of 21(5%) patient died after late operation. The causes of morbidity were vasospasm (19 cases), rebleeding (5 cases), hydrocephalus (1 case) in early operation and vasospasm (2 cases), hydrocephalus (1 case) in late operation. It is concluded that early operation is mandatory even in the patients with poor clinical status prior to surgery since early aneurysmal surgery can minimize the chance of rebleeding, permit more aggressive treatment against vaso-spasm and improve the clinical outcome.
Aneurysm* ; Aneurysm, Ruptured ; Hemorrhage ; Humans ; Hydrocephalus

The anterior communicating artery(Acomm) is one of more common sites of intracranial aneurysms. Surgery of anterior communicating aneurysm has been considered difficult because it is deep, and proximity to the vital diencephalic centers and it projects in various directions and its parent artery is thin or thourgh the sac, sometimes having vascular anomalies. Successful treatment of aneurysms by intracranial surgery requires careful planning of the surgical approach. The gyrus rectus approach to anterior communicating aneurysms is based on the belief that since aneurysms rupture at their fundus they can most safely be approached at their base because premature rupture of an aneurysm is deleterious to appropriate surgical treatment. From January to October 1982, 20 cases with ruptured aneurysms of the Acomm have been operated on using microsurgical procedures. We have presented 2 patients of Acomm aneurysms with certain difficult in clipping neck. The double aneurysms were obliterated with two clips and the other aneurysm was clipped with the long length clip and also the inclusion of adjacent vital nerves and vessels in the clips were avoided. Technical problems associated with the application of the clips are discussed.
Aneurysm* ; Aneurysm, Ruptured ; Arteries ; Humans ; Intracranial Aneurysm ; Neck ; Parents ; Rupture

We report a unique case of bilateral mirror image M1 aneurysms, one of which was an unruptured aneurysm arising from the proximal end of right middle cerebral artery fenestration with long loop and the other ruptured aneurysm from the contralateral side. We clipped ruptured aneurysm first and unruptured one in three months after the first operation. The difficulties of identifying this unusual vascular anomaly and possible problems during the surgery of an aneurysm at the site of fenestration are discussed with a review of the literature.
Aneurysm ; Aneurysm, Ruptured ; Intracranial Aneurysm ; Middle Cerebral Artery

Aneurysmal ruptures associated with middle cerebral artery(MCA) anomalies, such as a duplicated MCA and an accessory MCA, are quite rare. The authors reviewed the clinical relevance and possible etiology of these anomalies.
Aneurysm ; Aneurysm, Ruptured ; Intracranial Aneurysm* ; Middle Cerebral Artery* ; Rupture*

The authors report their experience with 73 cases of unruptured cerebral aneurysms in a consecutive series of intracranial microsurgery for 380 cerebral aneurysms in 307 patients from September, 1975 through March, 1984. Multiple, symptomatic, and incidental aneurysms are included in this group of 73 unruptured aneurysms. There was no mortality among fifty nine of these cases who had surgery. The only morbidity was due to massive postoperative vasospasm in a patient with multiple aneurysms, that developed on the site of ruptured aneurysm. Discussed in this report are characteristics of three categories of unruptured cerebral aneurysm patients and the principles of the management of unruptured aneurysms. In conclusion, all symptomatic unruptured aneurysms should be clipped immediately upon definite diagnosis, while decision for the operation of multiple unruptured aneurysms and aneurysms detected incidentally should be made with discretion by the surgeon.
Aneurysm ; Aneurysm, Ruptured ; Diagnosis ; Humans ; Intracranial Aneurysm* ; Microsurgery ; Mortality