<prompt> Upper Lid Retractors include?Muller muscle and superior rectusLevator palpabrae superioris and superior obliqueSuperior oblique and superior rectusLevator palpebrae superioris muller muscle  <response>: The levator palpebrae superioris is the impoant upper eye lid retractor. Injury or weakness to this muscle leads to ptosis. Deep pa of the elevator muscle is the Mullers muscle, which is sympathetically innveed. Ref: Textbook of Ophthalmic reconstructive surgeries p.786 