Comparison Of Reading Performance Following Implanation Of Extended Depth Of Focus, A Bifocal And A Trifocal Mfiol In Different Light And Contract Conditions

To evaluate and compare the binocular reading performance following implantation of a Bifocal, Trifocal and Extended Depth of Focus multifocal Intra Ocular Lens (MFIOL) implantation under different light and contrast condition using a standardised reading desk.

Prospective comparative randomized control study conducted in Phaco- Refractive Department of Nethradhama Super Speciality Eye Hospital, Bangalore

90 Patients fluent in reading English undergoing phacoemulsification with bilateral MFIOL implantation using either of the following technologies: Bifocal/Trifocal/EDOF (toric versions also) were included and divided into 3 groups with 30 patients in each. At 3 months Refraction and Binocular reading performance using Salzburg Reading Desk (SRD) “Version B.5.1 at patient preferred length for near and intermediate vision using reading speeds in Words per minute (WPM) (accepted with a minimum speed of 80 WPM) and minimum size of print read was noted in 3 types of contrast and luminance conditions: 100% (Photopic); 75% (Mesopic) and 30% (Scotopic).

In photopic Light conditions for near work EDOF IOL patients had highest reading speeds of 145.4 WPM followed by Trifocal and Bifocal but difference was not statistically significant but for intermediate distances the EDOF IOL patients had statistically significantly higher reading speeds of 207.6 compared to Trifocal group (126.8) and Bifocal group (115.8). In mesopic condition for both near and Intermediate work Trifocal IOL group had highest reading speeds for near (160.6) but result was not statistically significant (p 0.06) though for intermediate reading EDOF group performed better with 166.6 wpm speed. In scotopic condition for near and intermediate work EDOF group performed better and difference was statistically significant.

Different IOL technologies that is Trifocal which works better for mesopic conditions and EDOF IOL technologies which work better for scotopic and photopic light conditions can be prescribed to different patients based on careful consideration of their need and occupation among other factors.