Muscle not paralysed in retrobulbar block-

*A retrobulbar block is a regional anaesthetic nerve block in the retrobulbar space, the area located behind the globe of the eye. Injection of local anaesthetic into this space constitutes the retrobulbar block. This injection provides akinesia of the extraocular muscles by blocking cranial nerves II,III, VI, thereby preventing movement of the globe. Cranial nerve IV lies outside the muscle cone, but is blocked by diffusion of the local anaesthetic. *Superior oblique is supplied by cranial nerve IV. Ref: Delhi Ophthalmic society aicle