Functional and visual improvement with Prosthetic Replacement of the Ocular Surface Ecosystem (PROSE) scleral lenses for irregular corneas

Abstract

 

Purpose

 

Many patients with irregular corneas secondary to conditions such as keratoconus and post-operative astigmatism cannot tolerate rigid gas permeable contact lenses. Prosthetic Replacement of the Ocular Surface Ecosystem (PROSE) lenses can correct irregular astigmatism while simultaneously offering comfort, leading to improved function and visual acuity in these patients. The purpose of the present study was to evaluate the Doheny Eye Institute clinical experience with PROSE treatment for irregular corneas with outcome measures focused on improvement in visual acuity and visual function.

 

Methods

 

A retrospective chart review of 58 subjects (90 eyes) with irregular corneal surfaces referred to the Doheny Eye Institute for PROSE treatment between July 2009 and December 2011 was performed. Best corrected visual acuity before and after PROSE fitting was measured. Functional assessment before and after PROSE fitting was also measured using the Ocular Surface Disease Index, a 12-item questionnaire which grades severity of ocular discomfort and vision-related function.

 

Results

 

Keratoconus (43%) represented the largest group and post-penetrating keratoplasty (PK) astigmatism (31%) was the second largest group of patients with irregular astigmatism referred for PROSE fitting. Keratoconus patients had the greatest improvement in visual acuity following PROSE fitting with an 88% improvement in LogMAR vision. Post-PK astigmatism patients had the greatest improvement in OSDI scores with a 79% improvement after PROSE fitting.

 

Conclusions

 

PROSE treatment utilizing a customized scleral lens should be considered in all patients with irregular corneas that have failed conventional treatments prior to incisional surgery. Furthermore, the PROSE offers improved visual function, especially in patients who have irregular astigmatism secondary to penetrating keratoplasty.

 

 

Visual acuities pre and post PROSE fitting represented as logarithm of the minimal angle of resolution (LogMAR). All patients showed an average pre-PROSE acuity of 0.791 ± 0.68 and post-PROSE acuity of 0.151 ± 0.33 (p < 0.0001).

 

 

Ocular Surface Disease Index (OSDI) scores pre and post PROSE treatment. All patients showed an average pre-PROSE OSDI score of 58.42 ± 46.22 and post-PROSE OSDI score of 18.99 ± 17.93 (p < 0.0001).

 

Keywords: 574 keratoconus • 428 astigmatism • 477 contact lens