Abstract
Purpose :
To compare intraocular pressure (IOP) measurements by dynamic Sheimpflug analyzer (Corvis ST), noncontact tonometer, and ocular response analyzer after hyperopic small-incision lenticule extraction (SMILE).
Methods :
Thirteen eyes from 13 patients underwent hyperopic SMILE were prospectively enrolled in the study. The IOP and corneal biomechanical parameter were measured preoperatively and 1 week, 1 month, and 3 months after surgery with noncontact tonoometer (IOPNCT), Corvis ST(biomechanical corrected IOP, bIOP), and ocular response analyzer (Goldmann correlated Intraocular pressure (IOPg), cornea compensated IOP (IOPcc), cornea resistance factor (CRF), and cornea hysteresis (CH)). Linear mixed model was used to compare IOP values among four methods at each time point.
Results :
At the last visit, the safety index was 0.96 ± 0.12, and the efficacy index was 0.93 ± 0.14. No intraoperative or postoperative complications happened. IOPNCT, IOPg, IOPcc dropped significantly after surgery, with the amplitude being 3.15 ± 0.48 mmHg, 5.49 ± 0.94 mmHg, and 4.34 ± 0.97 mmHg respectively at the last visit. IOPNCT decreased o.11 ± 0.06 mmHg per removed central corneal thickness. bIOP kept agreeable during follow up. Before surgery, no difference was found among four measurements (P> 0.05). After surgery, IOPNCT and bIOP showed higher values than IOPg and IOPcc. IOPNCT at the last visit was correlated with preoperative IOPNCT (r=0.82, P= 0.001), and CRF at 3 months (r = 0.89, P=0.001).
Conclusions :
IOPNCT decreased after hyperopic SMILE, and its value is correlated with preoperative IOPNCT as well as corneal biomechanical properties. bIOP is an agreeable parameter to assess postoperative IOP.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.