<prompt> Orbital apex syndrome involvesOphthalmic division of trigeminal nerveOlfactory nerveMaxillary division of trigeminal nerveMandibular division of trigeminal nerve  <response>: Orbital apex syndrome is a complication of a paranasal sinus infection. Superior orbital fissure syndrome along with the involvement of maxillary division of trigeminal nerve and optic nerve is known as orbital apex syndrome. In superior orbital fissure syndrome, there is progressive paralysis of abducent, oculomotor and trochlear nerves. Ref: Diseases of ENT by Dhingra 6th edition Pgno : 200 