Temporary Balloon Occlusion to Test Adequacy of Collateral Flow to the Retina and Tolerance for

Summary: Two carotid ophthalmic artery aneurysms with incorporation of the artery into the neck were referred for endovascular assessment. Temporary balloon occlusion at the aneurysm neck was performed in an attempt to assess the adequacy of collateral flow to the retina. During infla-tion, the patients reported visual deterioration that re-solved upon deflation, which indicates that collateral blood flow was insufficient. The patients were referred for surgi-cal clipping to ensure preservation of the ophthalmic artery. Temporary balloon occlusion (TBO) of the internal carotid artery (ICA) is a well-accepted technique to evaluate collateral flow in patients with large or com-plex ICA aneurysms in whom arterial sacrifice or prolonged temporary occlusion of the ICA might oc-cur during surgical or endovascular therapy (1). Al-though surgical clipping has been the standard of care for most intracranial aneurysms in the past, endovas-cular treatment has evolved rapidly and is becoming integrated into the assessment and treatment para-digms for intracranial aneurysms. The decision to clip or coil depends on many factors, including the pa-tient’s vascular anatomy, aneurysm morphology, and collateral circulation (2). In this report, we describe the use of TBO to occlude temporarily both the ICA and the ophthalmic artery (OpthA) in an attempt to test the adequacy of collateral supply to the retina. Two patients with ca-rotid-ophthalmic aneurysms presented for endovas-cular assessment. Angiography demonstrated that the origin of the OpthA arose from the base of the an-eurysm in both cases. The potential risk of OpthA occlusion from coiling was tested with TBO. The patients reported visual deterioration, which was at-tributed to retinal ischemia from poor collateral flow. The patients were referred for surgical clipping