Clinical Evaluation of the New Rebound Tonometers Icare PRO and Icare ONE Compared With the Goldmann Tonometer

Performance of home-based self-tonometry (iCare HOME (TA022)) for measuring intraocular pressure among healthy and glaucoma patients

Introduction: The purpose of this study was to compare iCare HOME (TA022) with Goldmann applanation tonometer and to evaluate the self-tonometry measurements among the Indian population. Methods: Eligible patients underwent iCare HOME training through guided demonstration (verbal, pictorial, video) and practised self-tonometry measures using iCare HOME. Certification for independent iCare HOME measure was provided if first iCare HOME intraocular pressure (IOP) measurement fell within ± 5 mmHg of Goldmann applanation tonometer (GAT) measurement which was measured by the trained clinician (principal investigator). Certified participants underwent simulated home self-tonometry measurements using iCare HOME, and agreement with GAT IOP measurements was assessed. Results: Seven of 83 participants (8.43%) failed to complete the study due to difficulty in performing the task, leading to non-certification. Patients who could use the iCare HOME had a mean age of 53 ± 15.55years (53% males; 46% females). Only one in 12 subjects did not qualify to use iCare HOME. The overall mean difference between iCare HOME and GAT was 0.83 mmHg (95%, 3.92 and -2.25). At various pressure ranges, 7-16 mmHg, 17-23 mmHg and >23 mmHg, the mean difference between iCare HOME and GAT was 1.22 mmHg (95%, 4.32 and -1.86), 0.77 mmHg (95%,3.69 and -2.19), -0.11 mmHg (95%, 2.52 and -2.74) respectively. The intra-class correlation coefficient of the iCare HOME device was 0.997(95% CI,0.995-0.998). Conclusions: Patients were able to perform self- tonometry using iCare HOME with good reliability and safety. iCare HOME can be used to address the issue of difficulty in acquiring frequent and diurnal IOP measurements by patients doing self-tonometry from home.

Assessment of intraocular pressure measurement between Goldman applanation tonometer, rebound tonometer, non-contact tonometer, and its correlation with central corneal thickness

Purpose

To compare readings of intraocular pressure (IOP) taken with the Goldmann applanation tonometer (GAT), the non-contact tonometer (NCT), and the rebound tonometer (RBT), and to compare their correlation with central corneal thickness (CCT).

Methods

This was a prospective, cross-sectional, observational study to which patients above 18 years of age were enrolled. A total of 400 eyes of 200 non-glaucomatous patients underwent IOP recordings using the GAT, NCT, and RBT, and CCT was also noted. Informed consent of the patients was taken. The IOP readings taken via the three methods were compared and correlated with CCT. Paired t test was used to compare the two devices. Simple and multivariate linear regression analyses were used to study the relationship between factors. A P value less than 0.05 was considered significant. Correlation was determined using the Pearson correlation coefficient, and a Bland-Altman graph was plotted.

Results

Mean IOP measured by the NCT was 15.65 ± 2.80 mmHg, by the RBT was 14.23 ± 3.05 mmHg, and by the GAT was 14.69 ± 2.97 mmHg. The mean CCT was 510.61 ± 33.83 microns. The difference between mean IOP recorded by the NCT and that by the RBT was 1.41 ± 2.39 mmHg, between the NCT and GAT was 0.95 ± 2.03 mmHg, and between the GAT and RBT was 0.45 ± 2.22 mmHg. The difference between the IOP values was statistically significant (P < 0.005). All tonometers showed a statistically significant correlation with CCT, but it was observed that the NCT had a stronger correlation (0.4037).

Conclusion

The IOP readings taken by all the three methods were comparable; however, RBT values were closer to GAT values. CCT did influence the IOP values, and this should be kept in mind while evaluating.

Non-Invasive Intracranial Pressure Monitoring and Its Applicability in Spaceflight

INTRODUCTION: Neuro-ophthalmic findings collectively defined as Spaceflight-Associated Neuro-ocular Syndrome (SANS) are one of the leading health priorities in astronauts engaging in long duration spaceflight or prolonged microgravity exposure. Though multifactorial in etiology, similarities to terrestrial idiopathic intracranial hypertension (IIH) suggest these changes may result from an increase or impairing in intracranial pressure (ICP). Finding a portable, accessible, and reliable method of monitoring ICP is, therefore, crucial in long duration spaceflight. A review of recent literature was conducted on the biomedical literature search engine PubMed using the search term “non-invasive intracranial pressure”. Studies investigating accuracy of noninvasive and portable methods were assessed. The search retrieved different methods that were subsequently grouped by approach and technique. The majority of publications included the use of ultrasound-based methods with variable accuracies. One of which, noninvasive ICP estimation by optical nerve sheath diameter measurement (nICP_ONSD), presented the highest statistical correlation and prediction values to invasive ICP, with area under the curve (AUC) ranging from 0.75 to 0.964. One study even considers a combination of ONSD with transcranial Doppler (TCD) for an even higher performance. Other methods, such as near-infrared spectroscopy (NIRS), show positive and promising results [good statistical correlation with invasive techniques when measuring cerebral perfusion pressure (CPP): r = 0.83]. However, for its accessibility, portability, and accuracy, ONSD seems to present itself as the up to date, most reliable, noninvasive ICP surrogate and a valuable spaceflight asset.Félix H, Santos Oliveira E. Non-invasive intracranial pressure monitoring and its applicability in spaceflight. Aerosp Med Hum Perform. 2022; 93(6):517–531.

Evaluation of rebound tonometer iCare IC200 as compared with IcarePRO and Goldmann applanation tonometer in patients with glaucoma

Background

This study investigated the agreement between a new rebound tonometer, IC200, and IcarePRO and Goldmann applanation tonometry (GAT).

Methods

This was a prospective cross-sectional study. We measured the intraocular pressure (IOP) in 145 eyes of 145 glaucoma patients in the sitting position using GAT, IcarePRO, and IC200. IcarePRO and IC200 measurements were also obtained in the supine position. IC200 measurement was performed using two modes: single six (IC200-single) and automatic (IC200-continuous) six-measurements mode.

Results

All tonometers provided high reproducibility in both positions (all intraclass correlation coefficients > 0.90), although it was highest with GAT, followed by IC200-continuous and IC200-single and then IcarePRO. In the sitting position, the mean (± SD) IOPs of GAT, IcarePRO, IC200-single, and IC200-continuous were 14.5 ± 2.9 mmHg, 13.3 ± 3.2 mmHg, 11.6 ± 3.2 mmHg, and 11.5 ± 3.2 mmHg, respectively. IOPs measured with IcarePRO or IC200 were significantly lower than those with GAT, particularly in patients with low IOP. IOPs measured with all tonometers were significantly elevated in the supine position as compared with the sitting position, but this difference was significantly greater with IC200-single and IC200-continuous compared with IcarePRO. IOP elevation was significant in eyes without bleb versus those with bleb, but this finding was not observed when IOP was measured with IcarePRO. The IOPs of the single and continuous modes of IC200 were interchangeable in both positions.

Conclusions

GAT, IcarePRO, and IC200 had sufficiently high reproducibility, but measurements with IcarePRO may not be accurate in the supine position. Elevation of IOP in the supine position, especially in eyes with bleb, was more sensitively captured with IC200 than with IcarePRO.

Trial registration

Japan Clinical Trials Register, No. UMIN000039982.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40662-021-00249-z.

The Utility of iCare HOME Tonometry for Detection of Therapy-Related Intraocular Pressure Changes in Glaucoma and Ocular Hypertension

PURPOSE

To assess whether iCare HOME rebound tonometry can detect therapy-related changes during self-monitoring of intraocular pressure (IOP).

DESIGN

Prospective clinical trial.

PARTICIPANTS

A total of 43 eyes (n = 27 subjects) with open-angle glaucoma or ocular hypertension were enrolled during standard-of-care clinic visits. Participants were grouped into control eyes managed on stable therapy (n = 18 eyes) or therapy change eyes undergoing selective laser trabeculoplasty (SLT, n = 8 eyes), initiating topical therapy (n = 8 eyes), or adding a second medication to existing monotherapy (n = 9 eyes).

METHODS

Subjects recorded IOP 4 times daily for 1 week using iCare HOME tonometry. Upon tonometer return, subjects underwent SLT or new medication start; an additional week of iCare HOME measurements was collected after 4 to 6 weeks. Control subjects recorded an additional week of measurements after 6 weeks. Measurements were grouped into 4 time periods (5-10 am, 10 am to 3 pm, 3-8 pm, 8 pm to 1 am). Goldmann applanation tonometry (GAT) was performed at each study visit for comparison.

MAIN OUTCOME MEASURES

Detection of therapy response defined as an IOP reduction of ≥20%.

RESULTS

For eyes that demonstrated a therapy response by GAT (n = 11), iCare HOME detected a therapy response in 90.9% of eyes in ≥1 time period and 45.5% of eyes in all 4 time periods. In eyes without a GAT-measured therapy response (n = 14), iCare HOME detected a response for 71.4% (n = 10) of eyes in ≥1 time period and for 7.1% of eyes (n = 1) at all 4 time periods. In treatment eyes, intraday and interday average minimum and maximum IOP, as well as interday IOP range, were significantly reduced after therapy without a significant change in intraday IOP range. Control group eyes did not demonstrate a significant change in average IOP minimum, maximum, or range between study weeks.

CONCLUSIONS

Home tonometry with iCare HOME reliably detects therapy-related IOP changes in patients with glaucoma and ocular hypertension. Treatment responses correlated well with in-office GAT and may detect treatment responses missed by GAT. Intraocular pressure measurements via home tonometry provide additional clinical information regarding intraday and interday IOP fluctuation beyond standard of care in office GAT measurements. The iCare HOME is a valuable tool to monitor therapeutic efficacy in patients with glaucoma.

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

PURPOSE

iCare tonometers are easy-to-use and portable devices for measuring the intraocular pressure (IOP). Purpose was to evaluate the IOP values measured by both novel iCare ic100 and conventional model TA01i devices in unselected population.

METHODS

IOP was measured with iCare ic100 and TA01i tonometers in 149 participants aged 32-33 years (born in 1985 or 1986) of the Northern Finland Birth Cohort Eye 2 study. The right eye of each participant was selected for analysis. We also collected data on axial length, corneal curvature and central corneal thickness (CCT). Bland-Altman plot was used for comparing the values obtained by these devices.

RESULTS

Mean IOP measured with the ic100 device was 13.8 (3.4) mmHg, with TA01i it was 12.5 (3.0) mmHg. The mean difference between these devices was 1.30 mmHg (p < 0.001) and R2 was 0.694. In Bland-Altman analysis, the agreement between the two tonometers ic100 and TA01i was constantly good (mean difference -1.30, ic100 device showing higher measures). There was a correlation between IOP and CCT (r = 0.269, p < 0.001 for ic100 and r = 0.255, p = 0.002 for TA01i), but not with IOP and corneal curvature or IOP and axial length.

CONCLUSION

In summary, we found ic100 rebound tonometry to be both reliable and effective, although CCT may influence IOP measurements with ic100 and TA01i. Therefore, iCare ic100 is suitable for IOP measurement in large cohort studies.

Role of home monitoring with iCare ONE rebound tonometer in glaucoma patients management

AIM

To evaluate intraocular pressure (IOP) measurements and fluctuations using the iCare ONE rebound tonometer (RT-ONE), during home monitoring, in diagnosed and suspected glaucoma patients.

METHODS

A retrospective case series of consecutive patients with known glaucoma or glaucoma suspects who were followed-up and treated between January 2016 and January 2017. The study included 80 eyes of 40 patients with a mean age of 59.1±14.6y (range, 24-78). All patients have undergone 4-5d of IOP home monitoring with RT-ONE at morning, noon, afternoon, and night time.

RESULTS

Baseline mean IOP, as measured in the clinic (8 a.m.-12 p.m.), was 17.4±5.1 mm Hg, compared to RT-ONE home monitoring mean IOP of 15.6±4.1 mm Hg (P=0.002). Mean IOP was significantly lower at noon, afternoon and night times compared to clinic measured IOP and morning measurements (P=0.005). IOP peak measured during home monitoring was significantly higher compared to the clinic measured IOP (21.3±5.6 mm Hg and 17.4±5.1 mm Hg, P<0.001). IOP peaks during home monitoring demonstrated a majority of 47 peaks during morning measurements, compared to 23 at noon, 19 at afternoon and only 12 at night (P<0.001). The home monitoring results led to treatment modification of 44 eyes (55%), treatment regime was insufficient for 40 (50%) eyes.

CONCLUSION

Home monitoring IOP with RT-ONE can provide good assessment of mean IOP, IOP fluctuations and peaks throughout the hours of the day, which lead to an accurate treatment for glaucoma patients.

Acute Intraocular Pressure Responses to Reading: The Influence of Body Position

PRéCIS:: Greater intraocular pressure (IOP) values are observed when reading in the supine position in comparison with the sitting position, and thus, it should be considered by eye care specialists for the management of glaucoma patients or those at risk.

PURPOSE

IOP is sensitive to near work and body position, however, the influence of the body position adopted while performing near tasks remains unknown. This study aimed to assess the IOP changes induced by reading on a smartphone in sitting and supine position, and to explore whether these IOP changes differ between men and women.

METHODS

Twenty-four healthy young adults (12 men and 12 women) read a text on a smartphone placed at 30 cm for 25 minutes while lying down and sitting in 2 different days. A rebound tonometer, which allows assessing IOP in the supine position, was used to measure IOP before reading, during reading (5, 15, and 25 min), and after 5 minutes of recovery. Complementarily, the authors checked the level of sleepiness/alertness before reading, and the perceived levels of fatigue and discomfort after reading.

RESULTS

The data showed that reading induces an IOP rise [P<0.001, partial eta squared (ηp)=0.44]. These effects were more accentuated when reading in the supine position in comparison with the sitting position (P=0.019, ηp=0.23) with an increment of 2.4 mm Hg (14%) and 1.3 mm Hg (8%) after 25 minutes of reading, respectively. The IOP rises associated with reading did not differ between men and women (P=0.127). Participants reported greater levels of discomfort in the neck and back when reading in the sitting position (P=0.012, ηp=0.25).

CONCLUSIONS

The IOP rises associated with reading are greater when it is performed in the supine position in comparison with the sitting position. The present findings indicate that reading in the supine position should be discouraged in individuals who should avoid IOP increments or fluctuations.

The intraocular pressure response to lower-body and upper-body isometric exercises is affected by the breathing pattern

We assessed the mediating role of the breathing pattern adopted during isometric exercise on the intraocular pressure (IOP) response in the back squat and biceps curl exercises. Twenty physically active young adults performed sets of 1-minute isometric effort against a load corresponding to 80% of the maximum load while adopting three different breathing patterns: (i) Constant breathing: 10 cycles consisting of 3 s of inhalation and 3 s of exhalation, (ii) 10-sec Valsalva: 3 cycles consisting of 10 s holding the breath and 10 s of normal breathing, and (iii) 25-sec Valsalva: 2 cycles consisting of 25 s of the Valsalva maneuver and 5 s of normal breathing. A rebound tonometer was used to semi-continuously assesses IOP during the six sets of 1-minute isometric effort (2 exercises × 3 breathing patterns). We found a progressive IOP rise during isometric effort (P < 0.001, ηp2 = 0.83), with these increases being greater when the breath was held longer (P < 0.001, ηp2 = 0.58; 25-sec Valsalva > 10-sec Valsalva = constant breathing). There was a trend towards higher IOP values for the back squat in comparison to the biceps curl, although these differences did not reach statistical significance for any breathing pattern (corrected P-value ≥ 0.146, d ≤ 0.69). These findings reveal that glaucoma patients or those at risk should avoid activities in which the breath is held, especially when combined with physical exercise modalities that also promote an increment in IOP values (e.g. isometric contractions).

Comparision of intraocular pressure measured using the new icare 200™ rebound tonometer and the Perkins™ applanation tonometer in healthy subjects and in patients with primary congenital glaucoma

OBJECTIVE

To compare intraocular pressure (IOP) measurements obtained using the Icare 200™ (IC200) rebound tonometer and the hand-held version of the Goldmann Applanation Tonometer (Perkins™ tonometer, GAT) in patients with primary congenital glaucoma (PCG) and in healthy subjects.

MATERIAL AND METHODS

A total of 42 eyes of healthy subjects (G1) and 40 patients with PCG (G2) were analysed. The following clinical data were collected: gender, age, Cup/Disc ratio, central corneal thickness (CCT). IOP was determined in the examination room using the IC200 and GAT tonometers, in the same order. Agreement between both tonometers was determined using the intraclass correlation coefficient (ICC) and Bland-Altman plot. A linear regression analysis was used to establish the IOP was affected by the studied variables.

RESULTS

Mean IOP between both tonometers (IC200 minus GAT) was: G1=15.91 (2.57) mmHg vs. 15.06 (2.12) mmHg (mean difference, MD=0.84 (0.50) mmHg; P<.101) and G2=20.10 (6.37) vs.19.12 (5.62) (MD=0.98 (1.36); P=.474). Excellent agreement was found between IC200 and GAT in both groups (ICC=G1: 0.875 (95% CI; 0.768-0.933; P<.001); G2: 0.924 (95% CI; 0.852-0.961; P<.001), and there was a statistically significant correlation between the IOP difference measured with IC200 and GAT and CCT in G1 (B=0.021; 95% CI; 0.005-0.037; P=.008), but was not statistically significant in G2.

CONCLUSION

There was excellent agreement between the IC200 and GAT tonometers, both in healthy subjects and PCG, with a trend to overestimate IOP when measured with IC200. There was no influence by CCT on IOP measurements in patients with PGC.

Initial experience in self-monitoring of intraocular pressure

Background/aims

Diurnal variation in intraocular pressure (IOP) is a routine assessment in glaucoma management. Providing patients the opportunity to perform self-tonometry might empower them and free hospital resource. We previously demonstrated that 74% of patients can use the Icare® HOME tonometer. This study further explores Icare® HOME patient self-monitoring.

Methods

Patients were trained by standard protocol to use the Icare® HOME rebound tonometer. Patient self-tonometry was compared to Goldmann applanation tonometry (GAT) over one clinical day. Following this, each patient was instructed to undertake further data collection that evening and over the subsequent two days.

Results

Eighteen patients (35 eyes) participated. Good agreement was demonstrated between GAT and Icare® HOME for IOPs up to 15 mm Hg. Above this IOP the Icare® tended to over-read, largely explained by 2 patients with corneal thickness >600 um. The mean peak IOP during ‘clinic hours’ phasing was 16.7 mm Hg and 18.5 mm Hg (p = 0.24) over three days. An average range of 5.0, 7.0 and 9.8 mm Hg was shown during single day clinic, single day home and three day home phasing respectively (p =<0.001). The range of IOP was lower in eyes with prior trabeculectomy (6.1 mm Hg vs 12.2 mm Hg). All patients undertook one reading in the early morning at home with an average of 4.8 readings during, and 3.1 readings after office hours.

Conclusions

This small study shows that self-tonometry is feasible. The findings from home phasing demonstrated higher peak and trough IOPs, providing additional clinical information. Home phasing is a viable alternative. The cost-effectiveness of this approach has yet to be addressed.

ICare Pro: Age Dependent Effect of Central Corneal Thickness on Intraocular Pressure in Glaucoma and Ocular Hypertension Patients

Purpose: Measurement of the exact intraocular pressure (IOP) is essential in glaucoma diagnosis and follow-up, thus all therapeutic options affect IOP in order to win sighted lifetime. As it is known that corneal properties of glaucoma patients differ from normal subjects, the present study aimed to investigate the influence of CCT on rebound tonometry (ICT, ICare Pro) in glaucoma and ocular hypertension patients in dependency of age additionally considering different times of day.Methods: Three hundred sixty-two eyes of 190 subjects were included: 339 open-angle glaucoma and 23 ocular hypertension. IOP was measured at 5 different times of day (6 a.m., 12 a.m., 4 p.m., 9 p.m., and 0 p.m.) by Goldmann applanation tonometry (GAT) and Icare Pro rebound tonometry in a sitting position. Central corneal thickness was measured by central ultrasonic pachymetry (Pachymeter SP-100). Δ ICT was calculated as the difference of GAT, corrected according to age and CCT, and ICT, respectively at each time point.Results: All different GAT time points data correlated significantly (p < .05) with ICT time points. An age effect was observed on overall ICT (p = .02). A decrease of ICT was observed with increasing age. The within differences among ICT repeated measurements were significant as well. Additionally, repeated means of Δ ICT correlated significantly with age and CCT. Intercepts and coefficients were offered for each time point, respectively. GLM model yielded a relation between MD (dependent variable) and age together with CCT (age: p < .0001) and (CCT: p = .043).Conclusions: IOP measurements with ICare Pro were shown to be dependent on age, CCT and time of day in glaucoma and ocular hypertension patients. Thus, aging, corneal biomechanical properties and circadian rhythms should be taken into consideration when adjusting IOP.

Comparability of three intraocular pressure measurement: iCare pro rebound, non-contact and Goldmann applanation tonometry in different IOP group

Background

Measurement of intraocular pressure (IOP) is essential for glaucoma patients. Many factors such as central corneal thickness (CCT) can affect the accuracy of IOP measurement. The purpose of this study was to evaluate the agreement of IOP measured by non-contact tonometer (NCT), iCare pro rebound tonometer (iCare), and Goldmann applanation tonometer (GAT) in different IOP group.

Methods

This was a Hospital-based cross-sectional study. Two hundred subjects were enrolled in this study. All subjects underwent IOP measurement using an NCT–iCare–GAT sequence. Bland-Altman, Pearson correlation and intraclass correlation analysis were performed using SPSS 17.0 software. The influence of CCT on each IOP measurement methods was evaluated by linear regression analysis.

Results

The mean difference (Δ) of NCT–GAT did not differ from (Δ) iCare–GAT in IOP < 10 and 10–21 mmHg group. However, (Δ) NCT–GAT was significantly higher than (Δ) iCare–GAT in IOP 22–30 and > 30 mmHg group (P < 0.05). Bland–Altman analysis showed significant agreement between the three devices (P < 0.01). IOP measurements of the three methods were significantly correlated with CCT (P < 0.01).

Conclusions

ICare pro shows a higher agreement with GAT over a wide range of IOP compared with NCT. The consistency between the three tonometers was similar in a low and normal IOP range. However, NCT shows a greater overestimate of IOP in moderate and higher IOP group. The variability of IOP measurement affected by CCT is NCT > iCare pro > GAT.

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

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.

A comparison of Icare PRO and Perkins tonometers in anesthetized children

AIM

To compare intraocular pressure (IOP) measurements obtained with the Perkins applanation tonometer and Icare PRO (ICP) rebound tonometer in anesthetized aphakic or strabismus children. Furthermore, intra-operator correlation and inter-operator correlation have been evaluated, along with the effects of central corneal thickness (CCT) on IOP measurements.

METHODS

Seventy children undergoing examination under anesthesia with sevoflurane for aphakic patients and for surgery for strabismus were included. IOP have been measured twice immediately after anesthesia induction with both Perkins applanation tonometer (PAT) and ICP in one eye and by two different operators with both devices in the fellow eye. Furthermore, CCT was measured with ultrasound pachymetry Pacline (Optikon). Agreement between the device measurements has been evaluated using Bland-Altman analyses. Repeatability and reproducibility of the device have been evaluated with intraclass correlation coefficient (ICC) with a value > 0.75 associated with excellent reliability. The relationship between IOP and CCT has been evaluated with Spearman's correlation coefficient r and determination coefficient r².

RESULTS

Mean difference in IOP measurements between ICP and PAT was 1.97 mmHg ± 1.23 mmHg (p < 0.05). This difference appeared to be higher in aphakic patients (mean difference 2.15 ± 1.35) than in patients undergoing strabismus surgery (mean difference 1.83 mmHg ± 1.12). Intraclass correlation coefficient (ICC) is used to evaluate repeatability and reproducibility, which are both high for PAT (repeatability 0.96, reproducibility 0.76) compared with ICP (repeatability 0.81, reproducibility 0.70). Correlation coefficient between CCT and IOP is 0.66 for both ICP and PAT.

CONCLUSION

ICP tends to overestimate IOP compared to PAT. Repeatability and reproducibility are both high for PAT as compared to ICP. A significant correlation between IOP and CCT for both instruments has been demonstrated.

Comparison of Icare Pro Tonometry and Icare One Tonometry Measurements in Healthy Eyes

Objectives

To compare intraocular pressure (IOP) measurements obtained with the Icare Pro tonometer used in clinical practice and the Icare One self-tonometer.

Materials and Methods

Fifty-two eyes of 52 healthy, right-handed individuals with no prior intraocular surgery or ocular trauma, structural ocular pathology, or systemic disease were evaluated. IOP was first measured using the Icare Pro tonometer. The participants were then told how to use the Icare One tonometer and asked to measure their own IOP. The results were analyzed statistically using SPSS v.24.

Results

Of the 52 healthy participants, 16 (30.7%) were male and 36 (69.3%) were female. Their mean age was 31.6±6.3 (23-47) years. Mean IOP measured with the Icare Pro was 17.10±6.2 (11.5-25.2) mmHg, and the mean self-measured IOP with Icare One was 14.01±3.4 (7-24) mmHg. When the two methods were compared using Levene’s t-test, there was a significant mean difference of -3.08±0.6 (95% confidence interval: -4.39 -1.78; p<0.001).

Conclusion

In this study, there was a significant difference between the IOP measurements we made using the Icare Pro and the participants’ self-measured IOP using the Icare One, with the latter being relatively lower. This may be related to the fact that the participants were unfamiliar with using the Icare One. Although the Icare One is a promising tool for glaucoma patients to self-monitor their IOP, further studies are needed.

Icare-Pro Rebound Tonometer Versus Hand-held Applanation Tonometer for Pediatric Screening

PURPOSE

To compare intraocular pressure (IOP) measurements obtained using the new rebound tonometer Icare-Pro (Icare, Tiolat Oy, Helsinki, Finland) and the hand-held version of the Goldmann applanation tonometer (Perkins; Clement Clarke, Haag-Streit, Harlow, United Kingdom) in healthy children during clinical practice.

METHODS

In this prospective study, three IOP measurements were made using each tonometer in a single session, starting with the Icare-Pro. Participants were 173 non-anesthetized patients aged 1 to 16 years. Measurements were made in both eyes but only data for the right eye were entered in the analysis. Central corneal thickness, anterior chamber depth, and axial length were also measured in each patient. Data were compared by determining interclass correlation coefficients (ICCs) for each tonometer and representing the differences detected as Bland-Altman plots.

RESULTS

Good linear correlation was observed between IOP readings obtained using the Perkins and Icare-Pro tonometers (r = 0.87, P < .001), although the Icare-Pro readings were slightly higher (mean IOP difference: 0.26 ± 1.58 mm Hg, P = .037). The 95% limits of agreement between the two methods were 2.8 to -3.4 mm Hg. The ICC was 0.857 (95% confidence interval: 0.810 to 0.893), indicating good agreement. For both tonometers, a low but significant correlation was detected between IOP and central corneal thickness or age. However, no correlation of IOP was found with axial length or anterior chamber depth.

CONCLUSIONS

Pediatric IOP measurements determined using the new Icare-Pro rebound tonometer showed good correlation with those obtained using the hand-held Perkins applanation tonometer in a routine clinical examination with no need for general anesthesia. [J Pediatr Ophthalmol Strabismus. 2018;55(6):382-386.].

Icare® rebound tonometers: review of their characteristics and ease of use

The rebound tonometer has a unique mechanism for measuring intraocular pressure (IOP) and has become popular worldwide due to its ease of use. The most notable advantages are the lack of an air-puff and need for topical anesthesia, ease of operation and transport, and the ability to use it with children. Four rebound tonometers (Icare® TA01i, Icare PRO, Icare HOME, and Icare ic100) are currently available for clinical examination. It is important to understand the characteristics of each tonometer and select the most appropriate one because the IOP values and the purpose of measurement are different. In this review, with the goal of improving the understanding of a range of tonometers, the issues with each device are discussed.

The 24-hour intraocular pressure control by tafluprost/timolol fixed combination after switching from the concomitant use of tafluprost and timolol gel-forming solution, in patients with primary open-angle glaucoma

Objective

The aim of this study was to evaluate the 24-hour intraocular pressure (IOP)-control effect of the tafluprost/timolol fixed combination (TAF/TIM-FC) in patients with primary open-angle glaucoma after they switched from the concomitant use of tafluprost and timolol gel-forming solution.

Patients and methods

Twenty patients with primary open-angle glaucoma (12 male and 8 female; mean ± SD age, 57.0±7.1 years) were included in this study. The patients were treated for 8 weeks with the concomitant administration of tafluprost and timolol gel-forming solution (evening dosing). At the end of this period, the patients underwent 24-hour IOP monitoring (measured at 21:00, 01:00, 05:00, 09:00, 13:00 and 17:00). IOP was measured with Goldmann applanation tonometer (GAT) and Icare PRO at sitting position at all timepoints and additionally, at supine position with Icare PRO tonometer at 01:00 and 05:00. The patients were then all switched to TAF/TIM-FC treatment (evening dosing). After 8 weeks, the 24-hour IOP monitoring was repeated.

Results

Nineteen patients completed the study. The mean 24-hour IOPs in the concomitant and TAF/TIM-FC phases were 13.8±2.7 vs 13.3±2.8 mmHg (P=0.0033) with the GAT in the sitting position and 13.96±2.56 vs 13.48±2.56 mmHg (P=0.0120) with the Icare PRO in habitual positions. In comparison with the concomitant phase, significantly lower IOP was observed for the TAF/TIM-FC phase at 21:00 and 01:00 with the GAT and at 01:00 with the Icare PRO. In addition, the maximum IOP and fluctuations in IOP in habitual positions were lower for the TAF/TIM-FC phase than for the concomitant phase.

Conclusion

TAF/TIM-FC showed a stable 24-hour IOP-lowering effect and was equally or more effective than the concomitant use of tafluprost and timolol gel, both when sitting and when in habitual positions.

Diurnal Intraocular Pressure Fluctuations with Self-tonometry in Glaucoma Patients and Suspects: A Clinical Trial

SIGNIFICANCE

This article shows that self-tonometry can provide robust measures of diurnal intraocular pressure (IOP) and also detect changes to IOP in response to treatment within a short period of monitoring. These advances in IOP monitoring may contribute to improved management of glaucoma patients and suspects.

PURPOSE

The aim of this study was to prospectively investigate the utility of rebound self-tonometry performed over several weeks for detecting diurnal IOP fluctuations in glaucoma patients and suspects and also initial response to topical treatment in glaucoma patients.

METHODS

Forty patients were recruited following glaucoma-specific examination. Subsequent to successful training with the iCare HOME tonometer, patients were instructed to measure IOP, in a sitting position, four times a day over 4 to 6 weeks. Date, time, laterality, and IOP downloaded from the tonometer and clinical examination data, including applanation IOP and corneal thickness, were analyzed. A user satisfaction survey was also administered at study completion. t Test and analysis of variance were used to compare groups and IOP across days. Pearson correlation was used to compare measurements to Goldmann applanation tonometry and IOP measurements from the first day/s to the overall mean IOP.

RESULTS

Twenty-seven patients (18 suspects and 9 glaucoma patients) completed data collection. Patients self-measured IOP on 118 (±29) occasions for 40 (±7.4) days. Two dominant patterns of fluctuation were revealed: peak IOP upon awakening (n = 11) and at midday (n = 13). Diurnal IOP measured in the first 7 days showed strong correlation to diurnal IOP across the entire study period (r = 0.82, P < .0001). Within 24 hours of treatment commencement (latanoprost 0.005% ophthalmic solution), IOP reduced from 23.9 (±5.2) to 16.1 (±2.6) mmHg. Overall, patients rated the instrument as easy to use, although difficulties with correct alignment were expressed.

CONCLUSIONS

Rebound self-tonometry demonstrated utility for measuring diurnal IOP fluctuations in most patients, hence enhancing management of patient with or at risk of developing glaucoma.

Measurement of Intraocular Pressure by Patients With Glaucoma

Importance

The ability of patients to measure their own intraocular pressure (IOP) would allow more frequent measurements and better appreciation of peak IOP and IOP fluctuation.

Objective

To examine whether patients with glaucoma can perform self-tonometry using a rebound tonometer and examine patient acceptability.

Design, Setting, and Participants

An observational study in which IOP was assessed using Goldmann applanation tonometry and a rebound tonometer. Consecutive patients were provided with a patient information sheet and those consenting to take part in the study received standardized self-tonometry training and were then instructed to measure their own IOP under observation. This study was conducted at a glaucoma clinic at a university hospital from March 1, 2016, to December 30, 2016, and included both eyes of 100 patients with glaucoma or ocular hypertension.

Main Outcomes and Measures

The percentage of patients who could successfully perform self-tonometry. Complete success was defined by a good technique and an IOP reading within 5 mm Hg of that obtained by a clinician using the same device. A 3-item questionnaire was used to examine perceptions of self-tonometry among patients.

Results

Among the 100 patients, the mean (SD) age was 67.5 (10.9) years (53% female). A total 73 of 100 patients (73%) met the complete success criteria. An additional 6 patients could use the device but had IOP readings greater than 5 mm Hg different from those obtained by the clinician. On average, IOP by the rebound tonometer was 2.66 mm Hg lower than Goldmann applanation tonometry (95% limits of agreement, -3.48 to 8.80 mm Hg). The IOPs with the rebound tonometer were similar whether obtained by self-tonometry or investigator, with excellent reproducibility with an intraclass correlation coefficient of 0.903 (95% CI, 0.867-0.928). A total of 56 of 79 successful or partially successful patients (71%) felt self-tonometry was easy, with 73 of 79 (92%) reporting self-tonometry to be comfortable, and a similar number happy to perform self-tonometry in the future.

Conclusions and Relevance

Most patients could perform self-tonometry and the method was acceptable to patients. Self-tonometry has the potential to improve patient engagement, while also providing a more complete picture of IOP changes over time.

Comparison of intraocular pressure measurements using Goldmann tonometer, I-care pro, Tonopen XL, and Schiotz tonometer in patients after Descemet stripping endothelial keratoplasty

PURPOSE

Post-Descemet stripping endothelial keratoplasty (DSEK) patients are prone for intraocular pressure (IOP) elevations and glaucoma. Corneal characteristics influence various IOP measuring devices in various ways. The aim of this study was to evaluate the agreement between four different IOP measuring devices: Goldmann applanation tonometer (GAT), I-care pro, Tonopen XL, and Schiotz tonometr in patients who underwent DSEK.

METHODS

This was a prospective comparative study using a convenience cohort of post-DSEK patients with compact grafts. Post-DSEK patients had IOP measured using GAT, I-care Pro, Tonopen XL, and Schiotz tonometer. Measurements were compared and agreement assessed. Wilcoxon signed-rank test was used for comparison of means as variables did not show a normal distribution. Bland-Altman plots were used for assessing agreement.

RESULTS

Thirty eyes of 24 patients were included in the study. Mean time from DSEK surgery was 25.31 ± 13.05 months. Mean IOP with GAT, I-care pro, Tonopen XL, and Schiotz tonometer was 13.99 ± 3.76, 13.92 ± 3.36, 13.31 ± 3.89, and 12.83 ± 4.07, respectively. GAT, I-care pro, and Tonopen XL had similar mean IOP measurements (P = 0.135 and P = 0.551, respectively), while Schiotz tonometry measurements were higher (P = 0.046). Bland-Altman plots show good agreement between GAT, Tonopen XL, and I-care pro. GAT and Schiotz tonometry show less agreement, with large variations in the differences of measured IOP.

CONCLUSIONS

IOP measurements in post-DSEK patients showed good agreement between GAT and either Tonopen XL or I-care pro. Schiotz tonometer has large variations in this patient group. IOP measurements and IOP difference between devices were not dependent on central corneal thickness.

Effects of short-term mild hypercapnia during head-down tilt on intracranial pressure and ocular structures in healthy human subjects

Many astronauts experience ocular structural and functional changes during long-duration spaceflight, including choroidal folds, optic disc edema, globe flattening, optic nerve sheath diameter (ONSD) distension, retinal nerve fiber layer thickening, and decreased visual acuity. The leading hypothesis suggests that weightlessness-induced cephalad fluid shifts increase intracranial pressure (ICP), which contributes to the ocular structural changes, but elevated ambient CO2 levels on the International Space Station may also be a factor. We used the spaceflight analog of 6° head-down tilt (HDT) to investigate possible mechanisms for ocular changes in eight male subjects during three 1-h conditions: Seated, HDT, and HDT with 1% inspired CO2 (HDT + CO2). Noninvasive ICP, intraocular pressure (IOP), translaminar pressure difference (TLPD = IOP-ICP), cerebral and ocular ultrasound, and optical coherence tomography (OCT) scans of the macula and the optic disc were obtained. Analysis of one-carbon pathway genetics previously associated with spaceflight-induced ocular changes was conducted. Relative to Seated, IOP and ICP increased and TLPD decreased during HDT During HDT + CO2 IOP increased relative to HDT, but there was no significant difference in TLPD between the HDT conditions. ONSD and subfoveal choroidal thickness increased during HDT relative to Seated, but there was no difference between HDT and HDT + CO2 Visual acuity and ocular structures assessed with OCT imaging did not change across conditions. Genetic polymorphisms were associated with differences in IOP, ICP, and end-tidal PCO2 In conclusion, acute exposure to mild hypercapnia during HDT did not augment cardiovascular outcomes, ICP, or TLPD relative to the HDT condition.

Agreement among Goldmann applanation tonometer, iCare, and Icare PRO rebound tonometers; non-contact tonometer; and Tonopen XL in healthy elderly subjects

PURPOSE

To evaluate the inter-device agreement among the Goldmann applanation tonometer (GAT), iCare and Icare PRO rebound tonometers, non-contact tonometer (NCT), and Tonopen XL tonometer.

METHODS

Sixty healthy elderly subjects were enrolled. The intraocular pressure (IOP) in each subject's right eye was measured thrice using each of the five tonometers. Intra-device agreement was evaluated by calculating intraclass correlation coefficients (ICCs). Inter-device agreement was evaluated by ICC and Bland-Altman analyses.

RESULTS

ICCs for intra-device agreement for each tonometer were >0.8. IOP as measured by iCare (mean ± SD, 11.6 ± 2.5 mmHg) was significantly lower (p < 0.05) than that measured by GAT (14.0 ± 2.8 mmHg), NCT (13.6 ± 2.5 mmHg), Tonopen XL (13.7 ± 4.1 mmHg), and Icare PRO (12.6 ± 2.2 mmHg; Bonferroni test). There was no significant difference in mean IOP among GAT, NCT, and Tonopen XL. Regarding inter-device agreement, ICC was lower between Tonopen XL and other tonometers (all ICCs < 0.4). However, ICCs of GAT, iCare, Icare PRO, and NCT showed good agreement (0.576-0.700). The Bland-Altman analysis revealed that the width of the 95% limits of agreement was larger between the Tonopen XL and the other tonometers ranged from 14.94 to 16.47 mmHg. Among the other tonometers, however, the widths of 95% limits of agreement ranged from 7.91 to 9.24 mmHg.

CONCLUSION

There was good inter-device agreement among GAT, rebound tonometers, and NCT. Tonopen XL shows the worst agreement with the other tonometers; therefore, we should pay attention to its' respective IOP.

CLINICAL TRIAL REGISTRATION

Japan Clinical Trials Register; number: UMIN000011544.

Self-tonometry as a complement in the investigation of glaucoma patients

PURPOSE

To evaluate the reliability of intraocular pressure measured by patients with glaucoma themselves using a new hand-held tonometer and to observe whether the intraocular pressure (IOP) variations have the same pattern on different days while glaucoma treatment is constant.

METHODS

Eighty-seven patients diagnosed with open-angle glaucoma or ocular hypertension were recruited to the study. Intraocular pressure measured using Goldmann applanation tonometry (GAT) was compared with IOP measured using tonometry at baseline and on the second visit. Patients measured their IOP at home using the hand-held tonometers.

RESULTS

The mean difference between GAT and iCare^® values varies from 0 to 1 mmHg. Seventy-eight per cent of iCare^® measurements were within 3 mmHg of the GAT measurements. Approximately 64% of the study eyes had higher IOP in the morning than in the afternoon/evening. Circadian patterns differed between consecutive days in 47% of the study eyes. There were IOP peaks outside office hours in up to 16% of the study eyes.

CONCLUSION

Measurements made using rebound self-tonometry are accurate and could be used to complement the investigation of patients with glaucoma. Intraocular pressure curves provide valuable data usable when adapting glaucoma treatment.

Systematic Review of Current Devices for 24-h Intraocular Pressure Monitoring

Glaucoma is a common optic neuropathy that can lead to irreversible vision loss, and intraocular pressure (IOP) is the only known modifiable risk factor. The primary method of treating glaucoma involves lowering IOP using medications, laser and/or invasive surgery. Currently, we rely on in-office measurements of IOP to assess diurnal variation and to define successful management of disease. These measurements only convey a fraction of a patient’s circadian IOP pattern and may frequently miss peak IOP levels. There is an unmet need for a reliable and accurate device for 24-h IOP monitoring. The 24-h IOP monitoring devices that are currently available and in development fall into three main categories: self-monitoring, temporary continuous monitoring, and permanent continuous monitoring. This article is a systematic review of current and future technologies for measuring IOP over a 24-h period.

The Icare HOME (TA022) Study: Performance of an Intraocular Pressure Measuring Device for Self-Tonometry by Glaucoma Patients

PURPOSE

To evaluate the Icare HOME (TA022) device (Icare Oy, Vanda, Finland) for use by glaucoma patients for self-tonometry.

DESIGN

Prospective performance evaluation of a medical device.

PARTICIPANTS

One hundred eighty-nine participants with glaucoma or suspected glaucoma were recruited from the Wilmer Eye Institute, Baltimore, Maryland, between July 2014 and April 2015.

METHODS

Participants had standardized training and had to be able use the Icare HOME device independently. Subjects also had to be able to obtain the first intraocular pressure (IOP) measurement within 5 mmHg of Goldmann applanation tonometry (GAT). Those certified obtained 3 IOP measures using the HOME device, and these were compared with Icare TA01i and GAT IOP measurements.

MAIN OUTCOME MEASURES

The agreement between Icare HOME and reference tonometers was used to assess precision. The intraclass correlation coefficient was used to assess within-patient reliability for the HOME device.

RESULTS

Eighteen of 189 recruited patients were ineligible to take part in the study. Forty-four of 171 patients (25.7%) started but failed to complete the study: 7 stopped because of time concerns, 10 of 171 patients (6%) stopped because of difficulty using the device during certification, and 27 of 171 patients (16%) failed to be certified based on IOP. The HOME and GAT measurements agreed within 5 mmHg in 116 of 127 participants (91.3%); 2 participants (1.6%) had a difference of more than 7 mmHg. The mean difference between the Icare HOME and GAT measurements was -0.33 mmHg (standard deviation, 3.11 mmHg). The overall intraclass correlation coefficient for the HOME device was 0.92 (95% confidence interval, 0.89-0.95).

CONCLUSIONS

Not all participants could learn how to use the Icare HOME device, but for those who could, most were able to obtain measurements similar to those obtained by GAT. The Icare HOME device is safe and reliable for self-tonometry, but nearly 1 in 6 individuals may fail to certify in use of the device based on large differences in IOP when comparing GAT with the Icare HOME measurements. The device has the potential to address an unmet need by providing more frequent IOP measurements in a patient's day to day life.

Evaluation of a new rebound tonometer for self-measurement of intraocular pressure

BACKGROUND/AIMS

To compare the accuracy of self-obtained, partner-obtained and trainer-obtained measurements using the handheld Icare Home rebound tonometer with Goldmann applanation tonometry (GAT), and to evaluate the acceptability to subjects of Icare Home measurement.

METHODS

76 subjects were trained to use Icare Home for self-measurement using a standardised protocol. A prespecified checklist was used to assess the ability of a subject to perform self-tonometry. Accuracy of Icare Home self-measurement was compared with GAT using one eye per subject, randomly selected. Bland-Altman difference analysis was used to compare Icare Home and GAT intraocular pressure (IOP) estimates. Acceptability of self-tonometry was evaluated using a questionnaire.

RESULTS

56 subjects (74%, 95% CI 64 to 84) were able to correctly perform self-tonometry. Mean bias (95% limits of agreement) was 0.3 mm Hg (-4.6 to 5.2), 1.1 mm Hg (-3.2 to 5.3) and 1.2 mm Hg (-3.9 to 6.3) for self-assessment, partner-assessment and trainer-assessment, respectively, suggesting underestimation of IOP by Icare Home tonometry. Differences between GAT and Icare Home IOP were greater for central corneal thickness below 500 µm and above 600 µm than data points within this range. Acceptability questionnaire responses showed high agreement that the self-pressure device was easy to use (84%), the reading was quick to obtain (88%) and the measurement was comfortable (95%).

CONCLUSIONS

Icare Home tonometry can be used for self-measurement by a majority of trained subjects. IOP measurements obtained using Icare Home tonometry by self-assessment and third party-assessment showed slight underestimation compared with GAT.

[Ease of handling of first and second generation rebound tonometers]

PURPOSE

To evaluate the ease of handling of two rebound tonometers, which are designed for self-measurement of intraocular pressure (IOP) in a clinical setting by untrained patients.

METHODS

After self-measurement of the IOP with the rebound tonometers iCare ONE and iCare HOME, participants were asked to complete a questionnaire containing different subitems concerning ease of operation using a visual analog scale (1 = very good to 5 = very poor). Moreover, the feasibility and duration of measurement were tested.

RESULTS

A total of 147 subjects participated in this study. The mean score for general handling ability was 2.79 ± 1.01 for the iCare ONE and 1.85 ± 0.87 for the iCare HOME (p < 0.001). The evaluation of the subitems sense of safety (iCare ONE: 2.71 ± 1.03 and iCare HOME: 1.87 ± 0.81, p < 0.001) and comfort of measurement (iCare ONE: 2.07 ± 1.01 and iCare HOME: 1.66 ± 0.72, p < 0.001) also showed a significant discrepancy between the two tonometers. Participants needed significantly less time for a single valid measurement when using the iCare HOME tonometer (mean 66.14 ± 61.54 s) compared to the iCare ONE tonometer (mean 81.54 ± 69.51 s, p < 0.001).

CONCLUSIONS

A better handling of the iCare HOME rebound tonometer in comparison to the iCare ONE tonometer can be deduced on the basis of the subjective assessments of patients and the shorter duration of measurements. Moreover, the iCare HOME received a significantly better evaluation for all subitems. The accuracy of measurements using the iCare HOME still needs to be clarified.

Twenty-four-hour efficacy of preservative-free tafluprost for open-angle glaucoma patients, assessed by home intraocular pressure (Icare-ONE) and blood-pressure monitoring

PURPOSE

To evaluate the effect of preservative-free (PF) tafluprost on diurnal variation of intraocular pressure (IOP) and ocular perfusion pressure (OPP), measured by use of home IOP and blood-pressure (BP) monitoring devices, for primary open angle glaucoma (POAG) patients.

METHODS

Twenty-two eyes from 22 patients with POAG were studied. Initially, IOP was measured at the hospital by Goldmann applanation tonometry (GAT) and Icare-ONE rebound tonometry. Each patient was then instructed how to use the Icare-ONE and BP home monitoring devices. IOP and BP were measured at home by the patients, every 4 h, before and 2 weeks after once daily treatment with PF tafluprost (0.0015%) ophthalmic solution.

RESULTS

Intraclass correlations between different IOP measurements were greater than 0.8. PF tafluprost reduced mean diurnal IOP significantly for patients with POAG, from 15.7 ± 1.2 mmHg at baseline to 12.5 ± 0.6 mmHg 2 weeks after treatment (p < 0.001). It increased mean diurnal OPP from 48.5 ± 7.3 mmHg at baseline to 51.3 ± 7.0 mmHg post-treatment (p < 0.017).

CONCLUSIONS

Icare-ONE enables glaucoma patients to measure their own diurnal IOP fluctuations. Patient-measured Icare-ONE IOP readings showed that PF tafluprost effectively reduced diurnal IOP in eyes with POAG.