A rare variation of superior rectus muscle.

The extraocular muscles are responsible for all eye movements required to track and fix objects. Superior rectus muscle is located in the superior level of the orbital cavity, below musculus levator palpebrae superioris, tilted slightly to the lateral part of the orbit. In a routine dissection, we found a left, unilateral variation of the superior rectus muscle with no variation in other structures, such as nerves and vessels. The abnormal muscle presented in two parts - medial and lateral ones. The medial part bifurcated into two heads with different insertion points. It is a case of a rare variation of the extraocular muscles, which, to our knowledge, has not yet been reported.