Correspondence to Professor Sang Yeul Lee,

Year] doi:10.1136/ bjophthalmol-2014-305101 Aims To establish the novel concept of a functional eyelid centre to determine the optimal point for eyelid lifting in ptosis surgery. Methods This was a prospective study of 112 patients with congenital ptosis. The functional eyelid centre was defined as the point where the eyelid contour showed the best appearance when the upper eyelid was lifted manually. In patients who underwent frontalis suspension surgery using silicone rods, the postoperative outcome was assessed according to the fixation point of the rod. Results The average horizontal fissure width and the distance from the medial canthus to the mid-pupillary line were 21.9 and 10.1 mm, respectively. The functional eyelid centre was located 4.28±0.98 mm temporal to the mid-pupillary line. The outcomes of silicone rod surgeries were excellent when the rod was fixated 4.4 mm nasal and 3.9 mm temporal from the functional eyelid centre. These positions corresponded to 0.1 mm nasal and 8.2 mm temporal from the mid-pupillary line. Conclusions The functional eyelid centre was located slightly temporal to the mid-pupillary line. A better eyelid contour in ptosis surgery is produced when eyelid lifting is centred around the functional eyelid centre