A novel method for the intraoperative measurement of the centration of small aperture corneal inlays used for the treatment of presbyopia

Session Details

Session Title: Corneal Inlays for Presbyopia Correction

Session Date/Time: Sunday 11/09/2016 | 16:30-18:00

Paper Time: 16:36

Venue: Hall C1

First Author: : B.Will USA

Co Author(s): :                        

Abstract Details

Purpose:

To evaluate clinical outcomes for small aperture corneal inlays (SACI) using a new technique for measuring inlay centration intraoperatively

Setting:

Intraoperative measurements were performed on a consecutive series of patients undergoing implantation of a SACI in a private clinic

Methods:

Typically SACIs are centered by manually aligning the peripheral contour of the inlay to a 3.8 mm circular corneal mark centered manually on the first Purkinje image using direct visualization or; by aligning the inlay relative to the first Purkinje reflection observed using iris retro-illumination delivered by a hand held light source. We demonstrate a novel method that uses digital imaging technology combined with highly precise metrology software that can identify inlay position relative to target intraoperatively. Final centration alignments for all methods were determined using standardized techniques using the AcuTarget®, Visiometrics system.

Results:

Ideal centration of SACI is believed to be within 300 microns of the first Purkinje image. In our experience, SACI centered using a manually placed corneal mark in a sample of 42 eyes demonstrated a mean centration error of 171 ± 33 microns. By comparison, a series of 26 cases centered using the digital imaging system and metrology software resulted in a mean centration error of 85 ± 24 microns (P< 0.01). Speed of vision recovery and postoperative uncorrected near vision also appears better in the series with more accurate inlay centration.

Conclusions:

Centration and near vision quality of SACIs appears to be improved using a novel technique that uses intraoperative imaging and highly precise metrology software compared to techniques that attempt to align the inlay to a corneal mark manually centered or otherwise aligned to a location relative to the first Purkinje image as visualized by the surgeon under a coaxially sighted surgical microscope.

Financial Disclosure:

NONE