Refractive predictability in eyes with intraocular gas tamponade - results of a prospective controlled clinical trial.

Purpose: To determine the postoperative refractive error in eyes with intraocular gas tamponade in combined phacovitrectomy using a Z-haptic intraocular lens (IOL).

Methods: This prospective non-randomized case-control study compared patients with combined phacovitrectomy with or without intraocular gas tamponade to cataract surgery-only. The main outcome measure was the IOL power prediction error (PE). Secondary outcome measures were spherical equivalent, anterior chamber depth (ACD), and axial length.

Results: Thirty-four patients with epiretinal membranes and 18 patients with cataract only were enrolled. There were no statistically significant (>0.05) differences of IOL power PE or postoperative ACDs (=0.952-1.00). Nevertheless, IOL power PE indicated a myopic shift in cases with phacovitrectomy independent of gas tamponade (=1.00). No statistically significant between-group differences between secondary outcome measures were observed.

Conclusion: A myopic shift after phacovitrectomy seems to be independent of the use of intraocular gas tamponade. When using a Z-haptic IOL, aiming for slight residual hyperopia (+0.50 D) is suggested in patients having phacovitrectomy.