Comparison of Icare HOME and non-contact tonometer in intraocular pressure measurement in the early stage after ICL V4c implantation

Abstract

Purpose To investigate the characteristics of intraocular pressure (IOP) measurements using the Icare HOME rebound tonometer (RBT) and non-contact tonometer (NCT) during the early stage after implantable collamer lens (ICL) V4c implantation, and to assess the agreement between the two methods. Methods This prospective case series study included 104 eyes of 53 patients (mean age 28.77  ±  5.34 years), who underwent ICL V4c implantation. IOP was measured preoperatively, and at 0.5, 1, 2, 4, and 24 h postoperatively by Icare HOME and NCT, respectively. Results All surgeries were uneventful. IOP measurements by Icare and NCT preoperatively were 14.03  ±  2.90 mmHg and 14.09  ±  2.87 mmHg, respectively.The corresponding values were 12.56  ±  8.09 mmHg and 14.12  ±  6.52 mmHg (P > 0.05) at postoperative 0.5 h, 19.21  ±  8.74 mmHg and 19.60  ±  7.66 mmHg at postoperative 1 h (P > 0.05), 21.21  ±  8.10 mmHg and 20.31  ±  6.93 mmHg at postoperative 2 h (P > 0.05), 16.11  ±  5.89 mmHg and 17.04  ±  4.84 mmHg at postoperative 4 h (P > 0.05), and 14.04  ±  3.88 mmHg and 14.78  ±  2.80 mmHg at postoperative 24 h, respectively (P > 0.05). There was good agreement based on intraclass correlation coefficients (ICCs) between NCT and Icare HOME (all ICCs > 0.6 at different time points [range, 0.6986–0.956]). The Bland-Altman plot showed a mean percentage of over 95.81% of the points falling within the limits of agreement. There was a significant difference in the low IOP measurements (<10 mmHg) between Icare HOME and NCT (7.28  ±  2.55 vs. 10.65  ±  2.48, P < 0.001). Conclusion Icare HOME can be used for IOP measurement after ICL V4c implantation and demonstrated good agreement with NCT, except in cases with low intraocular pressure (<10 mmHg).