<prompt> Retrobulbar injection is given inInside muscle coneOutside muscle coneSubtenon spaceSubperiosteum  <response>: Refer: AK Khurana Comprehensive Ophthalmology, 6th edition, pg no. 444 Retrobulbar injection:- Injection in retrobulbar space inside the muscle cone Peribulbar injection:- Injection in peribulbarretrobulbar space outside the muscle cone Sub-tenon injection:- Injection beneath the tenon capsule, i.e. in subtenon space. It is also called parabulbar block Retrobulbar block involves depositing local anesthetic inside the muscle cone. It aims to block the ciliary nerves, the ciliary ganglion, and cranial nerves III, IV, and VI. 