To compare associated lash ptosis (LP) and lower lid retraction (LLR) with control fellow eyelid in patients with unilateral myogenic (MP) and aponeurotic (AP) ptosis before and after the ptosis repair and analyze factors affecting them.

Patients of >5 years old were included from June 2015 to April 2017. Other types of ptosis, associated strabismus and previous eyelid surgery were excluded. LP grading (0-3), lower lid margin reflex distance (MRD2), and photography were performed before and at least 6 months after ptosis repair. LLR was defined as more than 0.5 mm MRD2 in the ptotic side. Success of ptosis repair was defined as MRD1 equal or within 0.5 mm of the other side, LP success as ≥1 grade improvement, and LLR success as≥0.5 mm improvement at the last follow up. All procedure were performed by or under supervision of one oculo-facial plastic surgeon.

Seventy-eight cases with MP (58) and AP (20) with mean age of 27 years and median follow up of 10 months were included. LP was observed in 69 (89.5%) ptotic and 26 (33.3%) control lids. LLR was observed in 56.9% (33/58) of MP and 80% (16/20) of AP (P=0.06). Success of ptosis repair was observed in 84.5% (49/58) of MP and 100% of AP even though within 0.5 mm of under- or over-correction was observed in 7 cases. Mean LP grade was higher in the MP (1.5) than AP (1.1) group (P=0.04) which was significantly (P=0.001) decreased to 0.6 in the MP and 0.4 in the AP group (P=0. 14). Mean MRD2 was significantly (P=0.001) decreased from 5.5 to 5 in the MP and 5.6 to 4.9 mm in the AP group.

Lower LF and more severe ptosis were associated with more severe LP in the MP. Ptosis repair results in significant improvement of LP and LLR.