Balloon Occlusion Testing to Assess Retinal Collateral and Predict Visual Outcomes in the Management of a Fusiform Intraorbital Ophthalmic Artery Aneurysm: Technical Note and Literature Review

BACKGROUND AND IMPORTANCE:Aneurysms of the ophthalmic artery (OA) within the orbit and optic canal are extremely rare. Given the peripheral location of these aneurysms and the fact that most are fusiform, parent artery occlusion is preferred for symptomatic aneurysms. However, the impact of OA occlusion on vision is not always innocuous. Balloon occlusion testing (BOT) of the OA has the potential to gauge the possibility of visual compromise, in addition to assessing collaterals. While BOT has been assessed for carotid artery occlusion, its role in OA occlusion has not been well defined. CLINICAL PRESENTATION:We describe a patient with a 6-mm intracanalicular OA aneurysm who was treated with endovascular coil embolization of the aneurysm and occlusion of the parent artery. We performed a 30-min balloon occlusion test, in which we verified intact visual and neurological function. Collateral vascularity was confirmed. Complete occlusion was achieved and the patient recovered with intact visual and neurological function. We provide a review of literature pertaining to parent artery occlusion of OA aneurysms that occur within optic canal and orbit. A brief note on anatomy of OA and collaterals is provided. CONCLUSION:Endovascular parent artery occlusion is an effective treatment for OA aneurysms that occur in optic canal and orbit. Assessment of effect of occlusion on vision is important. BOT can assess this and provide valuable information. Recovery or preservation of visual function is highly dependent on preoperative visual status.