Abstract
Purpose:
To assess the refractive and clinical long-term outcomes of intrastromal ring segments (ISRS) implantation in a pediatric population.
Methods:
Retrospective study performed at Bascom Palmer Eye Institute including 7 eyes of 5 patients. Patients under 21 years old presenting with keratoconus, corneal pachymetry greater than 400microns, contact lens intolerance and clear corneas were included in the study. Implantation of the ISRS involved an off-label use of the FDA-approved INTACS (Addition Technology Inc., Lombard, IL). All surgeries, using the femtosecond laser Intralase (AMO, Santa Ana, CA, USA) for the creation of the intrastromal tunnels, were performed by the same surgeon. Manifest refraction, slit lamp examination, tonometry and fundus examination were performed one day, one month, every 4 months for a year and then every year postoperatively. The main outcome measures were uncorrected and corrected distance visual acuity, as well as spherical equivalent refraction and corneal findings at slit lamp examination. Paired t-test was performed using SPSS for statistical analysis.
Results:
Mean follow-up was 30.88+26.427 months ranging from 5 months to 77 months. The mean UDVA showed statistically significant improvement compared to baseline, from 0.835+0.312 LogMAR (Snellen 8/200E to 20/70) to 0.393+0.359 logMAR (Snellen 20/300 to 20/25) (p = 0.0005). The mean CDVA improved from 0.275+0.201 (Snellen 20/100 to 20/25) to 0.217+0.180 logMAR (Snellen 20/60 to 20/25) (p = 0.225), although the change was not statistically significant. Additionally, the mean spherical equivalent showed a non-significant improvement from -2.768+5.456 to -2.339+3.530 (p = 0.361). Two ISRS were removed: one for ocular irritation and the other one for corneal erosion. No other postoperative complications were recorded.
Conclusions:
Our results revealed that there was a statistically significant increase in the mean UDVA post-operatively among the pediatric patients. Although the use of INTACS in the pediatric population may be effective at improving visual acuity, further studies are needed to evaluate the safety of the procedure in this patient group.