Posters

Presbyopia treatment while preserving binocularity using laser anterior ciliary excision (LaserACE)

Poster Details

First Author: S.Rowen USA

Co Author(s):    A. Hipsley   O. Rozanova   K. Maia Rocha        

Abstract Details

Purpose:

To review current treatment modalities for presbyopia, and their effects on binocularity. Surgical presbyopia correction is plagued by difficulty in meeting patient expectations. Those treatments that maintain stereopsis should result in reduced asthenopia, increased patient satisfaction, and better surgical outcome subjectively.

Setting:

All procedures were performed at Chang Gung Memorial Hospital, Taipei, Taiwan. This presentation is also in collaboration with the research at the Irkutsk Branch of S. Fyodorov Eye Microsurgery Federal State Institution, Russia.

Methods:

A literature review of current presbyopia treatments and the effect on binocularity, followed by the effect of reduced stereopsis upon visual comfort and computer vision syndrome will be discussed. Formation of presbyopia is accompanied by the transformation of the previously developed relationships. The disintegration of the binocular interaction can be viewed as a consequence of the adaptation and dysadaptation processes of visual perception to the loss of accommodation. This should be considered when planning presbyopia surgery. Monovision correction using contact lenses, keratorefractive surgery, and intraocular lens implantation is often utilized, despite its partial occlusion resulting in reduction of depth perception. Diffractive IOL reduce visual quality, and stereopsis. Corneal implants which increase depth of field negatively impact stereo acuity as well. A presbyopia treatment performed away from the visual axis that protects binocular vision or produces natural improvement of binocular vision would be beneficial. Laser Anterior Ciliary Excision (LaserACE) may restore accommodative function without negatively impacting binocularity. A 2.94µm Er:Yag laser in 4 quadrants on the sclera over the ciliary muscle in three key zones to improve biomechanical accommodative forces. 24 patients underwent bilateral LaserACE treatment. Stereopsis as measured while wearing the near correction following LaserACE.

Results:

Stereopsis inclusion criteria for this procedure was that the patients had to achieve 100 arc seconds of stereopsis or lower. Preoperatively, average stereopsis was 75.77 arc seconds (N=24). Post-operative evaluation of stereopsis is reported from 1-18 months. One month postoperatively, it improved to 65.38 arc seconds (N=24). At 3 months, average stereopsis was 66.92 arc secons (N=24). This improved to 63.85 arc seconds at 6 months (N=24), and improved further to 60.00 arc seconds at 12 months (N=24). Stereopsis testing at 18 months found an average of 52.14 arc seconds (N=14). Uncorrected Distance VA did not show any statistically significant change. Both Uncorrected and distance corrected intermediate (60cm) and near (40cm) vision were improved. CatQuest surveys demonstrated high patient satisfaction with near visual tasks.

Conclusions:

LaserACE procedure using the VisioLite Er:Yag laser appears to be a safe and effective procedure for restoring range of visual performance for near (40cm) and intermediate (60cm) visual tasks without compromising stereopsis. While other presbyopia treatments may reduce visual quality and stereopsis, leading to asthenopia and reduced patient satisfaction, LaserACE appears to preserve normal binocular function. Patient satisfaction was high post-operatively and sustained over 18 months. The mechanisms of compensation of the loss of the primary accommodation may potentially be reversed after the LaserACE procedure. Long term studies are focused at analyzing determinants of these results and their implications. FINANCIAL INTEREST: One of more of the authors... receives consulting fees, retainer, or contract payments from a company producing, developing or supplying the product or procedure presented, One of more of the authors... research is funded, fully or partially, by a company producing, developing or supplying the product or procedure presented