Delayed cranial nerve palsy after successful coil embolization in cavernous sinus lesion

Cavernous sinus (CS) lesion is hard to access by surgical approach. With the development of endovascular technique, neurointerventional therapy is an alternative modality for CS lesions. This endovascular technique has been widely used for the past decade, avoiding the risks associated with surgical treatment. However, complications can still arise from coil embolization. Although immediate complication associate with embolic event or mass effect has been well described, but delayed (>1 year from treatment) nerve palsy after coil embolization is rare. We report two cases of delayed cranial nerve palsy after successful endovascular coil embolization in CS lesion.