Effects of the Intraocular Lens Type on Refractive Error Following Phacovitrectomy with Gas Tamponade

To compare the effects of the 4-haptic angulated (FA) intraocular lens (IOL) with the 2-haptic non-angulated (TNA) IOL vis-a-vis post-operative refractive error following phacovitrectomy with gas tamponade.A prospective study was conducted on 40 eyes of 40 patients who underwent phacovitrectomy with gas tamponade for repair of macular holes. During surgery, FA (n=20) or TNA (n=20) IOLs were implanted randomly. Post-operative prediction of mean numeric error (MNE) and mean absolute error (MAE), and anterior chamber depth (ACD) were evaluated 3 months post-operatively. Forty eyes undergoing phacoemulsification-only were used as controls.The MAE of the FA IOL group was significantly less than that of the TNA IOL group (0.41±0.94 versus 0.91±1.24 D, respectively) (p=0.040). The post-operative ACD of the FA IOL group (4.02±0.25 mm) was significantly greater than that of the TNA IOL group (3.54±0.31 mm) (p=0.031). There was less of a difference in ACDs between the phacovitrectomy and the phacoemulsification-only groups with FA IOLs (0.21±0.04 mm) than between those with TNA IOLs (0.51±0.06 mm) (p=0.010).Eyes undergoing phacovitrectomy with FA IOL implantation showed less myopic shift than did eyes with TNA IOL implantation. Anterior shift of the IOL in the FA IOL group was less than that of the TNA IOL group, as shown by ACD measurements. Thus, a myopic shift should be taken into account when calculating IOL power with TNA IOLs following phacovitrectomy with intraocular gas tamponade.