Aneurysms of Vessels of Vertebro-Basilar Region: Endovascular Treatment

A.V. Bocharov, S.B. Yakovlev, E.Yu. Bukharin,, S.R. Arustamyan

Burdenko Research Institute of Neurosurgery, Moscow, Russia

 

Direct surgical intervention on basilar artery aneurysms is characterized by a durable and traumatic approach. Aneurysms of this localization are inaccessible for clipping in some cases. At the same time, an endovascular method allows to achieve reliable occlusion of an artery in the majority of cases.

Materials and Methods. There were 28 patients, operated for aneurysms of vessels of the vertebro-basilar region. Their age varied from 7 up to 66 years. Small and big aneurysms were verified in 21 cases; they were giant in 7 patients. Small and large aneurysms manifested themselves in subarachnoid hemorrhages (SAH). The cases were operated 3 days-2 months after SAH (Hunt-Hess, I-III). Giant aneurysms were characterized by a pseudotumorous course.

Distribution of aneurysms according to localization was as follows: the basilar artery bifurcation - 18; between openings of the posterior cerebral and superior cerebellar arteries - 2; the vertebral artery - 3; an area of confluence of vertebral arteries + proximal segments of the basilar artery - 3; middle segments of the basilar artery - 2. Aneurysms' size varied from 3 up to 45 mm. We managed to perform reconstructive operations in all the cases with small and big aneurysms. Vasco 10, 14, 18 microcatheters were used for aneurysm catheterization. Occlusion of its cavity was performed with MDS microspirals (Balt, France) with a coil diameter of 3-15 mm.

Occlusion of vertebral arteries (deconstructive operations) with MABD TE and BALO-3 balloon-catheters (Balt, France) and use of a temporary functional occlusion test was used in all the patients with giant aneurysms. Operations were made under conditions of neuroleptanalgesia and systemic heparinization.

Results and Discussion. Reconstructive operations were performed in 21 patients; complete occlusion was achieved in 17 of them. Residual contrasting of a pericervical area of aneurysm was watched in 4 cases. There were no intraoperative complications.

One patient developed a complication in an early postoperative period (the 3rd day). It was represented by thrombosis of the posterior cerebral artery and gross focal neurologic syndrome.

A follow-up period varied from 6 up to 12 months (10 patients). A functioning part of aneurysm increased due to dislocation of the spiral coils in the direction of aneurysm's bottom in 3 cases. We added microspiral in 2 of them; the dominant vertebral artery was excluded in 1 patient. There were no SAH recurrences.

Deconstructive operations were made in 7 cases with giant aneurysms. Their size was more than 30 mm; they had no marked neck. Occlusion of the dominant vertebral artery was made in 5 patients. Occlusion of both vertebral arteries was performed in 2 patients with aneurysms, located in the area of their confluence and causing brain stem compression. It should be emphasized, that treatment of aneurysms of this localization is the most difficult problem. Manipulating a balloon, one should always keep in mind necessity of preserving a free opening of the inferior posterior cerebellar artery. As a rule, an area, located between a balloon and aneurysm, is not very large; thus, its reliable fixing in this place is not an easy task. Even in case of the most favorable concurrence of circumstances, exclusion of one vertebral artery does not give a desirable result because of preserved direct blood flow from the opposite artery. Exclusion of both vertebral arteries is a serious step, supposing existence of well developed posterior communicating arteries. Bilateral occlusion of vertebral arteries (2 cases) resulted in a severe postoperative course with augmentation of bulbar disorders. We managed to stabilize neurologic disorders in 1 case within 2 months; complete clinical recovery was watched in 6 months. One patient died on the 4 day after operation because of gross vascular disorders and impaired circulation in the brain stem.

Conclusions

  1. Endovascular treatment is a method of choice in aneurysms of the vertebro-basilar region.
  2. A small traumatic effect of reconstructive operations, a short rehabilitation period and high efficacy may be regarded as serious advantages over direct interventions in patients with small and large aneurysms with a marked neck; it especially concerns an acute period of SAH.
  3. Endovasal treatment of giant aneurysms is connected with great difficulties due to a high risk of neurologic disorders, which arise in deconstructive operations. Results in this category of cases can be improved by introduction of stents for intracranial vessels and wide-lumen extra- and intracranial vascular anastomoses into clinical practice.