Contralateral transcondylar approach for aneurysms of the posterior inferior cerebellar artery-vertebral artery complex

Contralateral Transcondylar Fossa Approach with Bilateral V3 Segment Exposure for Clipping of Vertebral Artery Aneurysm Which Deviates Across Midline: A Case Report and Review Article

This article reports a patient with unruptured right vertebral artery aneurysm which deviates across the midline to the left side. The contralateral (left) transcondylar fossa approach with bilateral V3 exposure is used for aneurysm clipping. The literature related to this technique is also reviewed.

Clipping of a PICA aneurysm located on the contralateral side of its parent vertebral artery in front of the brainstem: how I do it

BACKGROUND

Vertebro-PICA aneurysms may be challenging because of their relationship with the brainstem and the lower cranial nerves, especially when the vertebral artery is tortuous and the aneurysm is located in front of the brainstem, contralaterally to the parent vertebral artery. We describe the surgical technique for safe approach.

METHOD

Cadaveric dissection performed by the authors, provided comprehensive understanding of relevant anatomy. Intraoperative photos and videos show clipping of the aneurysm using a combined midline and far-lateral suboccipital craniotomy with a para-condylar extension. The literature reviews potential complications.

CONCLUSION

This combined approach allows safe clipping of such PICA aneurysms.

Multistage "Hybrid" (Open and Endovascular) Surgical Treatment of Vertebral Artery-Thrombosed Giant Aneurysm by Trapping and Thrombectomy

BACKGROUND

Surgical treatment of vertebral artery (VA)-thrombosed giant aneurysms requires achieving both obliteration of the parent artery to prevent bleeding and dome thrombectomy to relieve the brain stem from mass effect. To secure both proximal and distal control of complex VA aneurysms, the contralateral approach to the aneurysm might be a useful alternative, as previously described. We successfully treated a case of VA-thrombosed giant aneurysm in a new, original way by combining craniotomy (ipsilateral and contralateral) and the endovascular technique.

CASE DESCRIPTION

A 48-year-old man presented with a thrombosed giant aneurysm of the right VA compressing the brain stem. Treatment consisted of endovascular proximal ligation of the VA followed by 2-staged craniotomy for complete trapping of the aneurysm and intra-aneurysmal thrombectomy. The VA distal to the aneurysm was obliterated via contralateral craniotomy as only that provided adequate working space. Finally, intra-aneurysmal partial thrombectomy was performed through an ipsilateral craniotomy, which also made possible the obliteration of the eventually dangerous remaining vasa vasorum and additional proximal ligation of the VA.

CONCLUSIONS

Based on pathologic and surgical anatomical characteristics, a combination of an endovascular procedure with 2-staged craniotomy for complete trapping, thrombectomy, and vasa vasorum obliteration could be considered a feasible way to treat VA-thrombosed giant aneurysms located ventral to the brain stem and have their distal neck portions/patent vessel beyond the midline toward the contralateral side.

A Contralateral Transcondylar Fossa Approach with Bilateral V3 Segment Exposure for Repairing Complex Vertebral Artery Aneurysms

BACKGROUND AND IMPORTANCE

Microsurgical treatment for vertebral artery aneurysms can be approached through the lateral aspect of the brainstem and cerebellum. A contralateral approach may be selected in complex aneurysms with tortuous running and the intracranial vertebral artery distal to the aneurysm located in the contralateral cerebellopontine angle. When repairing the aneurysm, exposing the V3 segment before craniotomy is advantageous. We describe the detailed surgical procedures of the contralateral transcondylar fossa approach with bilateral V3 segment exposure for the repair of a complex vertebral artery aneurysm.

CLINICAL PRESENTATION

A 48-year-old woman presented with a 23-mm unruptured thrombosed fusiform aneurysm in the right vertebral artery. The aneurysm and the V4 segment distal to it deviated to the left, and the aneurysm was compressing the left anterior aspect of the medulla oblongata. We treated the patient with trapping and thrombectomy, using a contralateral transcondylar fossa approach with bilateral V3 exposure. During the procedure, proximal vascular control was achieved by occluding the contralateral V3 segment and distal control was achieved by occluding the V4 segment. The aneurysm was successfully trapped and decompressed. The patient's postoperative course was good and she was discharged with a modified Rankin Scale score of 0.

CONCLUSIONS

The contralateral transcondylar fossa approach with bilateral V3 exposure is feasible for the repair of complex vertebral artery aneurysms showing a deviated and difficult to access V4 segment proximal to the aneurysm. Bilateral V3 exposure may also facilitate aneurysm bypass procedures such as those using a V3-V4 anastomosis.

Clinical outcomes of ruptured and unruptured vertebral artery-posterior inferior cerebellar artery complex dissecting aneurysms after endovascular embolization

BACKGROUND AND PURPOSE

Surgical treatment of VA-PICA dissecting aneurysms is difficult and complication of LCNP is common. These lesions can be approached easily with endovascular technique, but complete obliteration can only be achieved in a small number of cases. Our aim was to report the clinical outcomes of VA-PICA dissecting aneurysms treated by endovascular embolization.

MATERIALS AND METHODS

Between 2001 and 2007, the authors treated 22 consecutive patients (15 men and 7 women; ranging in age from 12 to 59 years; mean age, 43 years) with VA-PICA dissecting aneurysms. Diagnosis of VA-PICA dissecting aneurysm was based on clinical, MR imaging, and cerebral angiography studies.

RESULTS

Of the 22 patients, 6 had unruptured aneurysms. One patient presented with headaches, whereas the remaining 5 patients showed brain stem ischemia. Four were treated with stent-only or stent-coil embolization, and 2 were treated with unilateral VA occlusion. Among 16 patients presenting with SAH, 10 were treated with stent-only or stent-coil embolization. The other 6 patients with SAH were treated by using unilateral endovascular VA occlusion. One patient could not return to his previous daily activities.

CONCLUSIONS

VA-PICA aneurysms are rare lesions associated with significant morbidity, and endovascular treatment strategies for these lesions were stent deployment with or without coil embolization and VA occlusion. Favorable clinical outcomes can be achieved with endovascular techniques.

Contralateral far-lateral approach for clipping of a ruptured vertebral artery-posterior inferior cerebellar artery aneurysm

Numerous nuanced approaches have been used to access posterior inferior cerebellar artery (PICA) aneurysms for microsurgical clipping. The authors report the case of a patient with a right vertebral artery (VA)-PICA aneurysm that was reached via a contralateral far-lateral approach. The wide-necked saccular/fusiform aneurysm arose from the lateral aspect of the right V(4) segment just proximal to the PICA origin, anterior to the jugular tubercle at the level of the hypoglossal canal. Computed tomography angiograms demonstrated the size and configuration of the aneurysm, and 3D reconstructions revealed the tortuosity of the right VA, defining its location just left of the midline adjacent to the lower clivus. A contralateral far-lateral approach to VA-PICA aneurysms should be considered when aneurysms cross the midline. Computed tomography angiography with volume rendering and interactive software capabilities can help identify the relationship of such an aneurysm to an individual's particular skull base osseous anatomy and is paramount in selecting the optimal microsurgical approach.