Systematic Review On Secondary Intraocular Lens Implantation In Aphakia.

Six main methods of secondary intraocular lens (IOL) fixation for aphakia with inadequate capsular support exist; iridiocorneal angle, pre-pupillary iris, retro-pupillary iris, sutured scleral, sutureless scleral and Yamane scleral fixation. A systematic review was conducted to assess their outcomes.  

Secondary IOL implantation for aphakia after previous cataract/lens surgery; complicated cataract surgery; trauma; subluxed IOL; or dislocated crystalline lens were included. Studies required a >6-month mean follow-up. The Methodological Index for Non-Randomised Studies tool was used for quality assessment.  

Primary outcome was LogMar best corrected visual acuity (BCVA), secondary outcomes were complications. 

17 full texts articles with a total of 1299 eyes met the inclusion criteria. 

The BCVA were as follows: iridiocorneal angle fixation -0.36; pre-pupillary iris fixation - 0.06-0.91; retro-pupillary iris fixation - 0.09- 0.79; sutured scleral lenses - 0.15-1.64; sutureless scleral fixated lenses - 0.08-1.45; Yamane lenses - 0.09-0.17. 

Statistically significant endothelial cell loss was highest in pre-pupillary fixation (mean loss 10.4%-18%), Hypotony was seen more in scleral sutured (2.14-28%) and sutureless scleral fixation (13.6-16.9%). Intraocular pressure rise was comparable between fixation types. Cystoid macular oedema was highest in retro-pupillary fixation and iridiocorneal angle fixation. Complications requiring further surgery was highest in scleral sutured IOLs.

The indication for secondary IOL insertion is heterogeneous, a significant confounder when comparing between different techniques. The Yamane technique may offer favourable long-term visual outcomes when compared to other techniques with a lower side effect profile.  There is a need for well-designed clinical trials comparing existing techniques.