Reproducibility and reliability of intraocular pressure self-measurement with iCare® HOME2 compared to Goldmann...

To evaluate the reproducibility and reliability of intraocular pressure (IOP) self-measurements with the iCare® HOME2 tonometer (ICH2, model TA023, Icare Oy, Vanda, Finland) in patients with ocular hypertension or glaucoma.

Fifty-two eyes of 29 patients were included. IOP was assessed consecutively by: air pulse tonometer (AT), Goldmann applanation tonometer (GAT), and ICH2 tonometer by the patient (ICH-P), then by an ophthalmologist (ICH-O). Reproducibility and agreement were assessed using a Bland-Altman test, and reliability was evaluated using an intraclass correlation coefficient (ICC).

Mean IOP by ICH-P, ICH-O, AT, and GAT was, respectively, 18.02±6.53mmHg, 17.08±5.65mmHg, 15.60±4.48mmHg and 14.42±5.00mmHg. Bland-Altman analysis between ICH-P and GAT and between ICH-O and GAT showed good reliability, finding a mean bias of 3.59mmHg and 3.09mmHg respectively, with a 95% limit of agreement of -1.48 to 8.68mmHg and -1.35 to 7.53mmHg, respectively. The repeatability of the measurements was excellent: ICC's of the measurements on each eye by the AT, ICH-O, ICH-P and GAT were 0.979, 0.991, 0.989 and 0.992, respectively.

Although ICH2 appears to overestimate IOP compared with GAT, there was good correlation between ICH2 self-measurements and GAT. iCare HOME2 appears to have good repeatability and reproducibility, and therefore may be a valuable tool to assess IOP in routine glaucoma monitoring.