Treatment of dissecting vertebral aneurysm

Therapeutic Progress in Treating Vertebral Dissecting Aneurysms Involving the Posterior Inferior Cerebellar Artery

Among the variations of vertebral artery dissecting aneurysms (VDAs), VDAs involving the posterior inferior cerebellar artery (PICA), especially ruptured and high-risk unruptured aneurysms, are the most difficult to treat. Because the PICA is an important structure, serious symptoms may occur after its occlusion. Retained PICAs are prone to re-bleeding because VDAs are difficult to completely occlude. There is therefore confusion regarding the appropriate treatment for VDAs involving the PICA. Here, we used the PubMed database to review recent research concerning VDAs that involve the PICA, and we found that treatments for VDAs involving the PICA include (i) endovascular treatment involving the reconstruction of blood vessels and blood flow, (ii) occluding the aneurysm using an internal coil trapping or an assisted bypass, (iii) inducing reversed blood flow by occluding the proximal VDA or forming an assisted bypass, or (iv) the reconstruction of blood flow via a craniotomy. Although the above methods effectively treat VDAs involving the PICA, each method is associated with both a high degree of risk and specific advantages and disadvantages. The core problem when treating VDAs involving the PICA is to retain the PICA while occluding the aneurysm. Therefore, the method is generally selected on a case-by-case basis according to the characteristics of the aneurysm. In this study, we summarize the various current methods that are used to treat VDAs involving the PICA and provide schematic diagrams as our conclusion. Because there is no special field of research concerning VDAs involving the PICA, these cases are hidden within many multiple-cases studies. Therefore, this study does not review all relevant documents and may have some limitations. Thus, we have focused on the mainstream treatments for VDAs that involve the PICA.

Cerebellar hemorrhage after embolization of ruptured vertebral dissecting aneurysm proximal to PICA including parent artery

BACKGROUND

Some complications related to vertebral artery occlusion by endovascular technique have been reported. However, cerebellar hemorrhage after vertebral artery occlusion in subacute phase is rare. In this report, we describe a patient who showed cerebellar hemorrhage during hypertensive therapy for vasospasm after embolization of a vertebral dissecting aneurysm.

CASE DESCRIPTION

A 56-year-old female with a ruptured vertebral dissecting aneurysm proximal to the posterior inferior cerebellar artery developed cerebellar hemorrhage 15 days after embolization of the vertebral artery, including the dissected site. In this patient, the preserved posterior inferior cerebellar artery fed by retrograde blood flow might have been hemodynamically stressed during hypertensive and antiplatelet therapies for subarachnoid hemorrhage, resulting in cerebellar hemorrhage.

CONCLUSION

Although cerebellar hemorrhage is not prone to occur in the nonacute stage of embolization of the vertebral artery, it should be taken into consideration that cerebellar hemorrhage may occur during hypertensive treatment.

Endovascular treatment of intracranial artery dissection: clinical and angiographic follow-up

Background. Intracranial artery dissections are rare and many controversies exist about treatment options. The aim of this study was to evaluate the efficacy and safety of the endovascular approach in patients with an intracranial dissection presenting with different symptoms. Methods. We prospectively evaluated the clinical features and treatment outcomes of 30 patients who had angiographically confirmed nontraumatic intracranial dissections over 4 years. Patients were followed up for 17 months, and their final outcomes were assessed by the modified Rankin Score (mRS) and angiography. Results. Sixteen (53.3%) patients had a dissection of the anterior circulation, whereas 14 (46.7%) had a posterior circulation dissection. Overall, 83.3% of the patients suffered a subarachnoid hemorrhage (SAH). Grade IV Hunt and Hess score was seen in 32% of the SAH presenting cases. Parent artery occlusion (PAO) with coil embolization was used in 70% of the cases. The prevalence of overall procedural complications was 23.3%, and all were completely resolved at the end of follow-up. No evidence of in-stent occlusion/stenosis or rebleeding was observed in our cases during follow-up. Angiography results improved more frequently in the PAO with coil embolization group (100%) than in the stent-only-treated group (88.9%) (P = 0.310) and the unruptured dissection group (5/5, 100%) in comparison with the group that presented with SAH (95.8%) (P = 0.833). Conclusion. Favorable outcomes were achieved following an endovascular approach for symptomatic ruptured or unruptured dissecting aneurysms. However, the long-term efficacy and durability of these procedures remain to be determined in a larger series.

Endovascular treatment of ruptured posterior circulation dissecting aneurysms

BACKGROUND

and aim: Dissecting aneurysms of the posterior circulation constitute a relatively uncommon subgroup of aneurysms. They account for 3-7% of cases of nontraumatic subarachnoid hemorrhage. Because of high risk, in most cases the patients require surgical or endovascular therapy. In this study we discuss the clinical efficacy of endovascular treatment with long-term follow-up in ruptured dissecting aneurysms of the posterior circulation.

MATERIALS AND METHODS

This retrospective study was conducted at our institution between January 1995 and June 2005. Eight patients (4 male; 4 females) ranging in age from 24 to 65 years (mean, 46.75 years), were included. All presented with SAH. Endovascular treatment was based on the configuration of the dissecting aneurysm. Attempt was made to occlude the dissecting aneurysm.

RESULT

A total of 8 ruptured dissecting aneurysms in the posterior circulation were treated. Out of them 5 were in the intradural vertebral artery, 2 in the basilar trunk and one in the proximal PCA. All the cases were technically successful. We have seen only two complications. The pre and post procedure (at the time of discharge) mean modified Rankin scores in the patients were 4.6 (SD 0.51) and 1.7 (SD 1.98). This improvement in Rankin score after endovascular treatment was statistically significant (Wilcoxon signed rank test, P=.017).

CONCLUSION

Endovascular management of these lesions is safe and effective mode of treatment and gives adequate protection from rebleed.

Endovascular management of vertebrobasilar dissecting aneurysms

BACKGROUND AND PURPOSE

Several approaches to the treatment of dissecting aneurysms of the vertebrobasilar system have been used. We evaluated our endovascular experience, which includes trapping and proximal occlusion.

METHODS

Thirty-five patients with intradural vertebrobasilar dissecting aneurysms presented to our institution between 1992 and 2002. Twenty-six were treated by endovascular means and two with surgery. In the endovascular group, 14 were in a supra-posterior inferior cerebellar artery (PICA) location, and three of these extended to the vertebrobasilar junction on the initial angiogram. Ten were located in an infra-PICA location, or no antegrade flow was seen in the PICA or anterior spinal artery. Two were located at the PICA with antegrade flow preserved in the branch. Twelve lesions were treated with trapping; another 14 were initially treated with proximal occlusion techniques, two of which eventually required trapping procedures. Follow-up images were obtained within 1 year of initial treatment in 24 patients. Mean follow-up for these patients was 3.5 years.

RESULTS

Initial treatments were technically successful and without complication in all 26 patients. Follow-up examinations showed complete cure in 19 of 24 patients. One patient died of global ischemia after presenting as Hunt and Hess grade 5 with subarachanoid hemorrhage. Two recurrent hemorrhages occurred in patients in the proximal occlusion group; one died, and the other underwent a trapping procedure. One patient developed contralateral vertebral dissection 24 hours after occlusion of a dissecting aneurysm of the dominant vertebral artery and died of a brain stem infarct. Another died of probable vasospasm, and the last died of an unknown cause 1 month after treatment. Two patients had recanalization despite an initial trapping procedure, both underwent further treatment. Mortality rate was 20% in the treated group (including the two patients treated surgically), with four of five deaths occurring during the initial hospital course. Mortality rate was 50% in the six patients in the untreated group who were available for follow-up.

CONCLUSION

Dissecting aneurysms of the vertebrobasilar system remain high-risk lesions because of their natural history. They can be managed by endovascular methods according to aneurysm location, configuration, collateral circulation, and time of presentation. Trapping results in better prevention of rehemorrhage. Proximal occlusion can achieve occlusion without manipulation of the affected segment when more direct endovascular occlusion or stent placement cannot be performed.

Endovascular management of vertebrobasilar dissecting aneurysms

BACKGROUND AND PURPOSE

Several approaches to the treatment of dissecting aneurysms of the vertebrobasilar system have been used. We evaluated our endovascular experience, which includes trapping and proximal occlusion.

METHODS

Thirty-five patients with intradural vertebrobasilar dissecting aneurysms presented to our institution between 1992 and 2002. Twenty-six were treated by endovascular means and two with surgery. In the endovascular group, 14 were in a supra-posterior inferior cerebellar artery (PICA) location, and three of these extended to the vertebrobasilar junction on the initial angiogram. Ten were located in an infra-PICA location, or no antegrade flow was seen in the PICA or anterior spinal artery. Two were located at the PICA with antegrade flow preserved in the branch. Twelve lesions were treated with trapping; another 14 were initially treated with proximal occlusion techniques, two of which eventually required trapping procedures. Follow-up images were obtained within 1 year of initial treatment in 24 patients. Mean follow-up for these patients was 3.5 years.

RESULTS

Initial treatments were technically successful and without complication in all 26 patients. Follow-up examinations showed complete cure in 19 of 24 patients. One patient died of global ischemia after presenting as Hunt and Hess grade 5 with subarachanoid hemorrhage. Two recurrent hemorrhages occurred in patients in the proximal occlusion group; one died, and the other underwent a trapping procedure. One patient developed contralateral vertebral dissection 24 hours after occlusion of a dissecting aneurysm of the dominant vertebral artery and died of a brain stem infarct. Another died of probable vasospasm, and the last died of an unknown cause 1 month after treatment. Two patients had recanalization despite an initial trapping procedure, both underwent further treatment. Mortality rate was 20% in the treated group (including the two patients treated surgically), with four of five deaths occurring during the initial hospital course. Mortality rate was 50% in the six patients in the untreated group who were available for follow-up.

CONCLUSION

Dissecting aneurysms of the vertebrobasilar system remain high-risk lesions because of their natural history. They can be managed by endovascular methods according to aneurysm location, configuration, collateral circulation, and time of presentation. Trapping results in better prevention of rehemorrhage. Proximal occlusion can achieve occlusion without manipulation of the affected segment when more direct endovascular occlusion or stent placement cannot be performed.