Analysis of reproducibility, evaluation, and preference of the new iC100 rebound tonometer versus iCare PRO and Perkins portable applanation tonometry

Abstract

Objectives: To analyze the reproducibility of the new iC100 rebound tonometer, to compare its results with the applanation tonometry and iCare PRO and to evaluate the preference between them. Materials and methods: For the study of reproducibility, 15 eyes of 15 healthy Caucasian subjects were included. Three measurements were taken each day in three separate sessions. For the comparative study, 150 eyes of 150 Caucasian subjects were included (75 normal subjects and 75 patients with glaucoma). Three consecutive measurements were collected with each tonometer, randomizing the order of use. The discomfort caused by each tonometer was evaluated using the visual analogue scale. Results: No statistically significant differences were detected between sessions. In the comparison between tonometers, the measurements with iC100 were statistically lower than those of Perkins (−1.35 ± 0.417, p = 0.004) and that iCare PRO (−1.41 ± 0.417, p = 0.002). The difference between PRO and Perkins was not statistically significant ( p = 0.990). The mean time of measurement (in seconds) with iC100 was significantly lower than with Perkins (6.74 ± 1.46 vs 15.53 ± 2.01, p < 0.001) and that PRO (6.74 ± 1.46 vs 11.53 ± 1.85, p < 0.001). Visual analogue scale score with iC100 was lower than Perkins (1.33 ± 0.99 vs 1.73 ± 1.10, p < 0.05). In total, 61.7% preferred iC100 against Perkins. Conclusion: The reproducibility of this instrument has been proven good. iC100 underestimates intraocular pressure compared to applanation tonometry at normal values and tends to overestimate it in high intraocular pressure values. Most of the subjects preferred iC100 tonometer.

Agreement between rebound (Icare ic200) and applanation tonometry (Perkins) in patients with primary congenital glaucoma

“…Authors such as Molero‐Senosiaín et al. (2019) reported significant underestimation of IOP when using the iCare 100 tonometer versus Icare PRO and Perkins. Nakakura et al.…”

“…These features are especially useful when the patient is anaesthetized such as when taking measurements in young children or poorly cooperative patients. Since the first iCare TA01m version, new versions have emerged designed to improve both measurement accuracy and reliability (Molero‐Senosiaín et al., 2019). The latest iCare model ic200 (RT200), besides having a magnetic probe, has a light to indicate the probe's correct (green) or incorrect (red) position.…”

Correlation of iCare ic100 tonometry with iCare TA01i in screening of unselected population in Northern Finland Birth Cohort Eye study

“…The reproducibility of ic100 instrument was good, although ic100 underestimated the IOP as compared to Perkins applanation tonometry at normal values while it overestimated it at high intraocular pressure values. 13 Current results show that IOP measured with ic100 was somewhat higher (mean 1.32 mmHg higher) than with TA01i device. Furthermore, in our previous study TA01i was mean of 0.11 mmHg higher than GAT.…”

“…The repeatibility (intraclass correlation coefficient of three measurements) with ic100 model in this study was very good (0.936). Furthermore, Molero-Senosiain et al 13 compared iCare ic100 and iCare Pro against Perkins tonometry. The reproducibility of ic100 instrument was good, although ic100 underestimated the IOP as compared to Perkins applanation tonometry at normal values while it overestimated it at high intraocular pressure values.…”

Outcome, influence factor and development of CLS measurement in continuous IOP monitoring: A narrative review

“…Therefore, to provide patients easy access to their IOP at any desired time, portable tonometry, such as Icare rebound devices, has been developed. Training before use is necessary to obtain accurate data using these devices [28]. However, a suitable body position is required for the IOP measurements using GAT, NCT, and portable tonometry, which not only disturbs sleep but also influences the IOP, thus misleading the clinicians.…”