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

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.

Critical pathway for primary open angle glaucoma diagnosis

AIM

To develop a critical pathway for primary open angle glaucoma (POAG) diagnosis intended to be efficient, to unify criteria, reduce resource use and minimize costs to the health system.

METHODS

We performed a systematic search on PubMed, Cochrane, Embase and ClinicalTrials.org databases and classified the quality of evidence from level I through III.

RESULTS

A critical pathway was designed by setting a key-decision step by step model on the basis of the best current evidence.

CONCLUSION

A critical pathway, evidence-based guideline, may be a useful tool intended to reduce costs while maintaining or even improving the quality of care for diagnosing a highly prevalent pathology such as open angle glaucoma.

Self-Monitoring Symptoms in Glaucoma: A Feasibility Study of a Web-Based Diary Tool

Purpose. Glaucoma patients annually spend only a few hours in an eye clinic but spend more than 5000 waking hours engaged in everything else. We propose that patients could self-monitor changes in visual symptoms providing valuable between clinic information; we test the hypothesis that this is feasible using a web-based diary tool. Methods. Ten glaucoma patients with a range of visual field loss took part in an eight-week pilot study. After completing a series of baseline tests, volunteers were prompted to monitor symptoms every three days and complete a diary about their vision during daily life using a bespoke web-based diary tool. Response to an end of a study questionnaire about the usefulness of the exercise was a main outcome measure. Results. Eight of the 10 patients rated the monitoring scheme to be “valuable” or “very valuable.” Completion rate to items was excellent (96%). Themes from a qualitative synthesis of the diary entries related to behavioural aspects of glaucoma. One patient concluded that a constant focus on monitoring symptoms led to negative feelings. Conclusions. A web-based diary tool for monitoring self-reported glaucoma symptoms is practically feasible. The tool must be carefully designed to ensure participants are benefitting, and it is not increasing anxiety.

Applications of the water drinking test in glaucoma management

Intraocular pressure (IOP) peaks and means have been considered important factors for glaucoma onset and progression. However, peak IOP detection depends only on appropriated IOP checks at office visits, whereas the mean IOP requires longitudinal IOP data collection and may be affected by the interval between visits. Also, IOP peak assessment is necessary to verify if the peak pressure of a given patient is in target range, to evaluate glaucoma suspect risk, the efficacy of hypotensive drugs and to detect early loss of IOP control. The water-drinking test has gained significant attention in recent years as an important tool to evaluate IOP peaks and instability. The main objective of this review was to present new findings and to discuss the applicability of the water-drinking test in glaucoma management.

Long-term home monitoring of intraocular pressure in pediatric glaucoma

PURPOSE

Diurnal fluctuation of intraocular pressure (IOP), implicated in progression of adult glaucoma, has been reported in children only in the context of office and short-term home monitoring. The purpose of this study was to evaluate long-term patterns of IOP fluctuation and changes resulting from outflow-enhancing intervention in pediatric glaucoma.

METHODS

Parent-measured home-based rebound tonometry (Icare, Finland Oy) in pediatric glaucoma patients was studied prospectively. IOP was monitored for more than 1 month, with requested measurements at least 3 times daily. Demographic and glaucoma-related information were collected for each participant. IOP was recorded at home on electronic data sheets. It was then evaluated for trends including mean overall IOP, IOP pre- and post-planned IOP-lowering interventions, and IOP spikes over determined time intervals.

RESULTS

IOP was measured in 14 eyes of 7 children (mean age, 9.3 ± 2.4 years) over a mean of 164.3 days (range, 75-341), with a mean of 2.46 readings daily. Six eyes of 5 children underwent attempted outflow improvement, with improved mean IOP before versus after intervention (26.6 vs 15.5 mm Hg, P < 0.0001) and decreased mean daily IOP fluctuation (8.4 vs 4.6 mm Hg, P < 0.001) for each. An IOP reading 20% greater than mean for an individual eye over the entire period (a pressure "spike") occurred in 19.3 ± 6.7% over 1 day, 62.9 ± 18.0% over 3 days, 80.8 ± 12.2% over 7 days, and 92.9 ± 9.4% over 14 days.

CONCLUSIONS

Long-term home monitoring in pediatric glaucoma proved feasible in this study population and often demonstrated large IOP fluctuations. A 14-day period of home monitoring provided >90% chance of identifying an IOP spike. Successful outflow improvement lowered both mean IOP and mean daily IOP fluctuations.