Endovascular Treatment of Bilateral Intracranial Vertebral Artery Dissecting Aneurysms Presenting with Subarachnoid Hemorrhage.

BACKGROUND:: Optimal management of bilateral vertebral artery dissecting aneurysms (bi-VDA) causing subarachnoid hemorrhage (SAH) remains unclear. OBJECTIVE:: To investigate the treatment methods and outcomes of bi-VDA causing SAH. METHODS:: Seven patients were endovascularly treated for bi-VDA causing SAH. Treatment methods and outcomes were retrospectively evaluated. RESULTS:: Two patients were treated with 2 overlapping stents for both ruptured and unruptured VDA, 2 with 2 overlapping stents and coiling for ruptured VDA while conservatively for unruptured VDA, 1 with internal trapping (IT) for ruptured VDA and stent-assisted coiling for unruptured VDA, 1 with IT for ruptured VDA and 2 overlapping stents for unruptured VDA, and 1 with IT for ruptured VDA and single stent for unruptured VDA. None had rebleeding during follow-up (range, 15 - 48 months). All patients had favorable outcomes (mRS, 0 - 2). On follow-up angiography at 6 - 36 months, 9 treated and 2 untreated VDA revealed stable or improved state, while 3 VDA in 2 patients showed regrowth. Of the 3 recurred VDA, one was initially treated with IT but recurred due to retrograde flow to ipsilateral posterior inferior cerebellar artery (PICA), the second was treated with single stent but enlarged, and the last was treated with 2 overlapping stents and coiling but recurred from the remnant sac harboring PICA origin. All 3 recurred VDA were re-treated with coiling with or without stent insertion. CONCLUSION:: Bilateral VDA presenting with SAH were safely treated with endovascular methods. However, endovascular treatment may have a limitation for VDA with PICA origin involvement.