Complexity of Treatment for Pica Aneurysm: A Case Series and Review of Literature
The frequency of posterior circulation aneurysms is 15% with 3% arising from the PICA. Our institution is presenting a 3-case series of such aneurysms.
1st: 75 year-old Caucasian female with acute SAH from a ruptured right distal PICA aneurysm. Patient presented with GCS of 11T with diffuse intraventricular SAH. Initial angiogram showed a distal saccular right PICA aneurysm that was deemed not appropriate for coiling. The patient underwent a right suboccipital paramedial craniotomy approach for clipping of aneurysm. The exposure was extended into the foreman magnum with decompression of the cisterna magna. The aneurysm was localized by angiogram and ultrasound. Post-operative, the patient recovered and was eventually discharge to rehab.
2nd: 80 year-old Caucasian female with ruptured left proximal PICA aneurysm. The patient presented with GCS of 10T. Initial angiogram showed a possible re-bleed. The patient was then taken for an extended left suboccipital craniotomy for clipping of aneurysm. Exposure included removal of the foreman magnum and partial laminectomy of C1 arch. The vertebral artery was localized and used to identify the VB junction. The patient's post-operative course showed dependency of the vent. The family withdrew treatment and concentrated on comfort care.
3rd: 57 year-old Hispanic male presented with a 5-day history of headache and subacute SAH. On angiogram, a PICA aneurysm was identified at the VA junction. The patient underwent coiling of aneurysm but with intraprocedural rupture. The aneurysm was able to be coil with control of the hemorrhage. Post-operatively the patient recovered, but develop hydrocephalus, which was treated with shunting. The patient was discharge to home.
By far, aneurysms of the PICA region are the most difficult to treat. Aneurysms of the vertebrobasilar junction represent an exceptional challenge to the neurosurgeon. Surgical access to these deep and confined lesions is hampered by the direct proximity of highly vulnerable neural structures such as the brainstem and cranial nerves. Different surgical avenues consisting of different supra and infratentorial approaches have been developed over the years to gain access to these treacherous lesions. More recently, the adaptation of skull base approaches with endovascular techniques borrows a great opportunity to improve to treatment of these complex aneurysms. Equally, endovascular treatment of PICA/VB artery aneurysms is technically challenging due to their intimate locations in the posterior circulation. Although, endovascular results of PICA aneurysms are not well established, successful coiling of these aneurysms can potentially lead to better clinical outcome for this patient population. In all, the successful treatment of PICA/VB artery aneurysms constitutes the combination of endovascular techniques as well as employing open skull base approaches.