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. 2022 Dec 1:10:1030458.
doi: 10.3389/fbioe.2022.1030458. eCollection 2022.

Predictive models for IOPs measured with NCT, GAT, and ORA among patients undergoing SMILE

Tian Han  1   2   3   4 , Wanru Shi  1   2   3   4 , Yingjun Chen  1   2   3   4 , Yang Shen  1   2   3   4 , Ye Xu  1   2   3   4 , Xingtao Zhou  1   2   3   4
Affiliations

Predictive models for IOPs measured with NCT, GAT, and ORA among patients undergoing SMILE

Tian Han et al. Front Bioeng Biotechnol. .

Abstract

Purpose: To develop predictive models for the intraocular pressure (IOP) of patients undergoing small incision lenticule extraction (SMILE) procedures, measured with a noncontact tonometer (NCT), Goldmann applanation tonometry (GAT), and an ocular response analyzer (ORA). Methods: In this prospective study, a total of 104 eyes (-6.23 ± 2.06 diopters) of 52 patients (24.38 ± 4.76 years) undergoing SMILE procedures were included. The intraocular pressure was measured (IOPNCT with NCT, IOPGAT with GAT, and IOPcc and IOPg with ORA) before surgery and at postoperative 6 months. Information on age, preoperative and attempted spherical equivalent (SE), ablation depth, preoperative values and postoperative changes in central corneal thickness (CCT), K1, K2, Km, corneal hysteresis (CH) and corneal resistance factor (CRF) values was collected in order to predict IOPs. Results: All surgeries were uneventful. At postoperative 6 months, the efficacy and safety index were 1.04 ± 0.15 and 1.08 ± 0.18, respectively. Significant decreases were detected in postoperative IOPNCT, IOPGAT, IOPcc, and IOPg compared to preoperative values (all p < 0.001). No relationship was found between any IOP and ablation depth, attempted SE, and preoperative SE, as well as CCTdifference (all p > 0.05). Predictive models for IOPs were constructed to predict preoperative values, and R 2 values were 67.5% (IOPNCT), 64.5% (IOPGAT), 78.7% (IOPcc), and 82.0% (IOPg). The prediction band of IOPNCT and IOPGAT was 7.4-15.1 mmHg and 8-16 mmHg, respectively. Conclusion: Predictive models for IOP measurements after SMILE procedures can be helpful in clinical practice.

Keywords: Goldmann applanation tonometry (GAT); intraocular pressure (IOP); noncontact tonometer (NCT); ocular response analyzer (ORA); small incision lenticule extraction (SMILE).

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Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

FIGURE 1
FIGURE 1
Preoperative and postoperative values of IOPNCT, IOPGAT, IOPg, and IOPcc. Significant decreases in all IOPs were detected compared to preoperative values (all p < 0.001). Except for IOPNCT and IOPcc (p = 0.631) and IOPGAT and IOPg (p = 0.382), all other preoperative IOPs differed from each other (all p < 0.05) (IOPNCT and IOPGAT p = 0.005, IOPNCT and IOPg p = 0.049, IOPGAT and IOPcc p = 0.001, and IOPcc and IOPg p = 0.015). After the surgery, except for IOPNCT and IOPGAT (p = 0.095), each postoperative IOP was different from other the three IOPs (all p < 0.001).
FIGURE 2
FIGURE 2
Decreases in IOPNCT, IOPGAT, IOPg, and IOPcc. Each of the changes in IOP differed from the other three IOPs (all p < 0.01) (IOPNCT and IOPg (p = 0.005), IOPGAT and IOPcc (p = 0.006), and other p < 0.001)
FIGURE 3
FIGURE 3
Scatterplots between IOPNCT, IOPGAT, IOPg and IOPcc, and CCT changes, ablation depth, and attempted SE.
See this image and copyright information in PMC

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