A study of the embryology and the anatomy of the ophthalmic artery shows that the branches to the important sensory structures arise proximal to the second intraorbital segment of the vessel. Damage to vision will be avoided if embolisation is restricted to vessels anterior to this "safety point", which is easily recognised on an angiogram. The ideal point of injection of emboli is even more distal and varies with the extent of the lesion and the material used. Three cases are described with vascular lesions supplied by the ophthalmic artery and embolised with Histoacryl.