Changes in the sulcus and anterior chamber after horizontal or vertical intraocular lens orientation: prospective randomized study.

PURPOSE: To assess the changes in ciliary sulcus (CS) and anterior chamber diameters (ACDi) after horizontal or vertical orientation of the intraocular lens (IOL) in the capsular bag in relation to preoperative axial length (AL) and anterior chamber depth (ACD).

SETTINGS: University hospital.

DESIGN

Prospective, randomized study.

METHODS

The first eye was randomized to receive the IOL horizontally or vertically, and the second eye had the opposite orientation. Undilated ultrasound biomicroscopy at 0 to 180 degrees, 45 to 225 degrees, 90 to 270 degrees, and 135 to 315 degrees axes were performed preoperatively and at 6 weeks. Data on preoperative AL and ACD were collected. Change in CS and ACDi in relation to preoperative AL and ACD. Postoperative CS and ACDi in the horizontal vs vertical IOL placement groups and right vs left eyes ( ClinicalTrials.gov ID: NCT04208633).

RESULTS

46 patients (92 eyes) were recruited. After horizontal placement of the IOL, there was a significant correlation between AL and change in horizontal CS for right ( r = 0.68, P = .01) and left eyes ( r = 0.68, P = .04). After vertical placement, there was a significant correlation between AL and ACD with change in vertical ACDi in right (AL: r = 0.71, P = .01; ACD: r = 0.66, P = .02) and left eyes (AL: r = 0.93, P < .01; ACD: r = 0.65, P = .04), respectively. There was no significant difference in preoperative and postoperative change with horizontal and vertical IOL placements in the right vs left eyes.

CONCLUSIONS

When the IOL is horizontal in the capsular bag, the horizontal CS increases with decrease in AL. The vertical ACDi increases with increased AL or ACD when the IOL is vertical in the capsular bag.