Correlation of wound healing with accommodative stability utilising iTrace wavefront aberrometry

Session Details

Session Title: Advanced Tools for Outcome Assessment

Session Date/Time: Tuesday 17/09/2019 | 08:30-10:30

Paper Time: 08:54

Venue: Free Paper Forum: Podium 4

First Author: : J.Mehta SINGAPORE

Co Author(s): :    A. Hipsley   Y. Liu   B. Hall                       

Abstract Details

Purpose:

To evaluate the scleral wound healing and accommodative stability following Laser Scleral Microporation (LSM) using a 2.94um Erbium Yttrium Aluminum Garnet (Er:YAG) scanning laser system.

Setting:

Singapore National Eye Centre 11 Third Hospital Ave, Singapore 168751

Methods:

Six non-human primates (n = 12 eyes) at presbyopic age underwent LSM on the sclera consisting of 41 micropores of 225um spot size in a diamond matrix pattern on 4 oblique quadrants of the eye to improve biomechanical pliability. The eyes were harvested 1, 6, and 9 months postoperatively for histological analysis by Hematoxylin and Eosin staining, and immunohistochemistry analysis. Ray-tracing aberrometer and double-pass wavefront were used to objectively measure visual acuity, higher-order aberrations, depth of focus, the visual Strehl ratio based upon the optical transfer function, true accommodation, pseudoaccommodation, and the effective range of focus (EROF) of the eyes.

Results:

Histological analysis revealed inflammatory cell infiltrates and focal coagulative necrosis around the scleral micropores at 1 month, with less in the collagen-gel treated group. At 9 months, there was minimal scleral fibroblast migration into the micropores. At the scleral laser area the expression of fibronectin, tenascin, and HSP-47 was more distinct in the non-collagen-treated group, but they subsided with time. In all eyes, there was no expression of CD11b, CD45, α-SMA, or CD31 in the sclera. EROF increased by approximately 8D on average, which corresponded to a 5D increase in true accommodation and a 3D increase in pseudoaccommodation.

Conclusions:

LSM is associated with an acceptable range of inflammatory and wound healing responses expected with this wavelength of laser. Wound healing response correlated well with accommodative stability, most likely due to the minimal thermal damage associated with the laser beam profile. Both wound healing and accommodation showed long term stability up to 9 months after treatment.

Financial Disclosure:

receives consulting fees, retainer, or contract payments from a company producing, developing or supplying the product or procedure presented