Posters

Preoperative factors influencing success in MyoRing implantation in keratoconic patients

Poster Details

First Author: S.Mosavi IRAN

Co Author(s):    K. Jadidi   M. Naderi   F. Nejat   L. Janani   S. Serahati   A. Alishiri

Abstract Details

Purpose:

To identify preoperative factors that influence the success in Myoring implantation in Keratoconic patients

Setting:

Ophthalmology Department, Bina Eye Hospital, Tehran,Iran.

Methods:

In a case series ,medical records of 87 eyes of 87 patients who underwent MyoRing intra-corneal implants using the PocketMaker Microkeratome due to keratoconus between April 2012- March 2013 were retrospectively analayzed using SPSS version 16 for Windows for variables before implantation and visual outcome after Myoring implantation. Variables included age,gender, uncorrected visual acuity( UCVA), best corrected visual acuity (BCVA), spherical equivalent(SE) , central corneal thickness(CCT) and keratometry reading .The mean age of patients was 29.34 ± 7.0 years (range 18 to 49 years). The MyoRing dimensions were selected according to the MyoRing nomogram. The eyes were graded after the last follow-up based on uncorrected visual acuity difference (UCVAd); difference of pre-op UCVA and post-op UCVA to worst ,moderate and best subgroups. Fifty -nine eyes(78.8%) had UCVAd of ≥ 7 lines (best group). In 14 eyes(18.7%), UCVAd ranged between 2 lines and 7 lines ( moderate group) and 2 eyes (2.7%) had UCVAd of less than 2 lines (worst group).

Results:

The mean value of uncorrected visual acuity (UCVA) , best corrected visual acuity (BCVA) and spherical equivalence(SE) improved significantly ,while the mean value of central corneal thickness (CCT) and keratometry reading were significantly reduced postoperatively. Considering the entire study group, the strongest predictor was UCVA between the moderate and best group . The mean value of UCVA was 0.73 (0.26) logMAR and 1.25 (0.2) logMAR in moderate and best group respectively (p=0.001).In contrary to relative improvement for SE , no significant difference was found between moderate and best group( p=0.075) . No statistical correlation was found between age ,sex, keratometric values, CCT , BCVA and visual outcome . No intra or postoperative complication happened . Meanwhile, patients with exchange, shift and penetrating keratoplasty( PK) status were excluded from study.

Conclusions:

MyoRing implantation is safe and effective for the treatment of keratoconic patients with lower preoperative visual acuity. In addition, according to the new grading system for Myoring implantation success, preoperative UCVA is considered the most important indicator for surgical success in MyoRing treatment of Keratoconus. FINANCIAL INTEREST: NONE