Continuous 24-hour monitoring of intraocular pressure patterns with a contact lens sensor: safety, tolerability, and reproducibility in patients with glaucoma

Abstract

OBJECTIVE To examine the safety, tolerability, and reproducibility of intraocular pressure (IOP) patterns during repeated continuous 24-hour IOP monitoring with a contact lens sensor. METHODS Forty patients suspected of having glaucoma (n = 21) or with established glaucoma (n = 19) were studied. Patients participated in two 24-hour IOP monitoring sessions (S1 and S2) at a 1-week interval (SENSIMED Triggerfish CLS; Sensimed AG). Patients pursued daily activities, and sleep behavior was not controlled. Incidence of adverse events and tolerability (visual analog scale score) were assessed. Reproducibility of signal patterns was assessed using Pearson correlations. RESULTS The mean (SD) age of the patients was 55.5 (15.7) years, and 60% were male. Main adverse events were blurred vision (82%), conjunctival hyperemia (80%), and superficial punctate keratitis (15%). The mean (SD) visual analog scale score was 27.2 (18.5) mm in S1 and 23.8 (18.7) mm in S2 (P = .22). Overall correlation between the 2 sessions was 0.59 (0.51 for no glaucoma medication and 0.63 for glaucoma medication) (P = .12). Mean (SD) positive linear slopes of the sensor signal from wake to 2 hours into sleep were detected in both sessions for the no glaucoma medication group (S1: 0.40 [0.34], P < .001; S2: 0.33 [0.30], P < .01) but not for the glaucoma medication group (S1: 0.24 [0.60], P = .06; S2: 0.40 [0.40], P < .001). CONCLUSIONS Repeated use of the contact lens sensor demonstrated good safety and tolerability. The recorded IOP patterns showed fair to good reproducibility, suggesting that data from continuous 24-hour IOP monitoring may be useful in the management of patients with glaucoma. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01319617.

Figures

Figure 1

Intraocular pressure patterns with the SENSIMED Triggerfish® contact lens sensor in individual patients in two different 24-hour sessions spaced one week apart (Session 1, S1= blue line; Session 2, S2 = yellow line). 1 A (example of high IOP pattern reproducibility: r = 0.80): 53-year old Caucasian male glaucoma patient under treatment with once-daily prostaglandin analogue and twice-daily combined carbonic anhydrase inhibitor/ß-blocker eyedrops. Previously, the patient had undergone selective laser trabeculoplasty in the study eye. Sleep times (supine) are from 1025 to 0800 (S1) and 0900 to 0820 (S2). GAT-IOP was at 12 mmHg (before CLS) and 14 (after CLS) in S1 and 13 mmHg and 13 mmHg in S2, respectively. 1 B (example of high IOP pattern reproducibility: r = 0.85): 52-year old Asian female with suspicion of glaucoma. It is unknown whether the patient instilled her prostaglandin analogue eyedrops (not mentioned in the diary). Sleep times (supine) are 2300 to 0830 (S1), interrupted between 2330 and 0100 (awake/supine) and 00.00 to 0230 and 0600 to 0730 (S2). GAT-IOP was at 25 mmHg (before CLS) and 22 (after CLS) in S1 and 24 mmHg and 24 mmHg in S2, respectively. 1 C (example of moderate IOP pattern reproducibility: r =0.65): 59-year old Caucasian female with suspicion of glaucoma. In S1, the patient took a nap (supine) between 1400-1500; went to sleep/supine at 2300, awoke at 0115, remained awake/sitting until 0200, then went back to sleep/supine until 0730. In S2, the patient went to sleep/supine at 2315, woke up and was awake/sitting between 0230 and 0600 and again sleeping/supine from 0600-0730. The different sleep patterns between the two sessions seem to correspond well with observed IOP patterns. GAT-IOP was at 22 mmHg (before CLS) and 23 (after CLS) in S1 and 21 mmHg and 22 mmHg in S2, respectively. 1 D (example of low IOP pattern reproducibility: r =0.21): 20-year old Caucasian male with suspicion of glaucoma and irregular sleep behavior. According to patient's diary, signal increases at 10.45-12.30, 1515-1715, 2015-2045, and 0345-0815 (S1) and 1030-1330 and 0430-0800 correspond to supine/sleep. The patient spent the rest of the nocturnal period working at the computer. GAT-IOP was at 26 mmHg (before CLS) and 28 mmHg (after CLS) in S1 and 27 mmHg and 28 mmHg in S2, respectively.