A patient present with unilateral painful ophthalmoplegia. Imaging revealed an enlargement of cavernous sinus on the affected side. The likely diagnosis is:

Tolosa - Hunt Syndrome / Orbital Apex Syndrome One of the lesion of orbital apexQ Characterized by painful, acute ophthalmoplegia, with or without involvement of the optic nerve and ophthalmic division (V1) of trigeminal nerveQ Responds promptly to steroid treatment Tolosa described a case in which a mass of granulation material was found around carotid aery in the cavernous sinus and asymmetrical enlargement of cavernous sinus, now referred as Tolosa - Hunt syndromeQ.