Randomized Controlled Trial of Intraocular Lens Orientation for Dysphotopsia

To evaluate whether orientation of the optic-haptic junction of an intraocular lens (IOL) during cataract surgery could decrease the incidence and/or severity of positive and negative dysphotopsia.

Prospective, randomized controlled trial.

A total of 163 patients (326 eyes) in a private practice scheduled to have bilateral implantation of a Tecnis monofocal IOL (ZCB00) (Johnson & Johnson Vision) were randomly assigned to have the optic-haptic junction positioned vertically, horizontally, superonasally, or inferonasally. Patients with known visual field defects or best-corrected vision less than 20/80 were excluded. Patients were surveyed for positive and negative dysphotopsia symptoms at 1 week and 4-6 weeks after surgery. Patients were blinded to the orientation whereas researchers were not. Data were analyzed to compare the differences in positive and negative dysphotopsia incidence and severity.

IOL oriented vertically in 82 eyes (25.2%), horizontally in 72 eyes (22.1%), superonasally in 94 eyes (28.8%), and inferonasally in 78 eyes (23.9%). Significant differences were noted between orientations in incidence of negative dysphotopsia at 1 week postoperatively (P = .019) and 4-6 weeks postoperatively (P = .002). Patients in the superonasal group had the worst outcome at both time periods, and the horizontal group had the best outcome at 4-6 weeks. No differences were noted for positive dysphotopsia incidence or severity.

The orientation of the optic-haptic junction of a monofocal IOL was significantly associated with incidence of negative dysphotopsia after surgery, with the horizontal orientation performing best at 4-6 weeks.