Current Trends in Tonometry and Tonometer Tip Disinfection

A comparison of iCare and Goldmann applanation tonometry measurements during the COVID-19 pandemic: a retrospective study

PURPOSE

To evaluate factors associated with differences in intraocular pressure (IOP) readings between iCare and Goldmann applanation tonometry (GAT) in established glaucoma patients.

METHODS

This retrospective comparative study included clinical data of 350 eyes from 350 established glaucoma patients who had iCare and GAT IOP measured by an ophthalmic technician and a glaucoma specialist, respectively. The main outcome measure was the difference in IOP measurements of the right eyes with iCare and GAT.

RESULTS

The intraclass correlation coefficient (ICC) between GAT and iCare was 0.90. The mean IOP difference between tonometers was - 0.18 ± 2.89 mmHg. Bland-Altman plots indicated a 95% limit of agreement of - 5.8 to 5.5 mmHg. Central corneal thickness (CCT) and age were significantly correlated with the difference in IOPs of the iCare and GAT. GAT-IOP and age were significantly associated with the absolute difference in measured IOP of the two tonometers. The difference in measurements was not significantly associated with prior glaucoma surgery, average global index of optical coherence tomography, axial length, technician years of experience and certification, and IOP range.

CONCLUSION

Although there is good agreement between the iCare and GAT mean values, these devices are not interchangeable in glaucoma patients due to the wide range of the limit of agreement.

Optical illusions: The vital importance of instructions for use and intentionally approaching eye device processing

BACKGROUND

The purpose of this process and quality improvement activity was to address opportunities identified with cleaning, disinfection, and sterilization requirements for eye devices, and implement a robust and sustainable processing system to support safe patient care.

METHODS

Through the lean 6 Sigma methodology, the evaluation of noncritical, semicritical and critical device processing was conducted. A hierarchal approach to law, regulation, manufacturer's instructions for use, evidence-based guidelines, consensus documents, facility risk assessments, policy, and procedure was conducted. Over 15 diverse clinical areas within a large health care network were assessed for utilization of ophthalmic and optometric devices, with the review of inventory for manufacturer-instructed cleaning, disinfection and sterilization compliance.

RESULTS

An interdepartmental multidisciplinary team with oversight of over 10 service lines led the implementation of point-of-use treatment, transport, high-level disinfection, sterilization, storage, and documentation based on intended use.

CONCLUSIONS

During this experience, infection Preventionists performed a vital role in supporting a highly reliable cleaning, disinfection, and sterilization process. This undertaking required a team approach to apply instructions for uses and evidence-based practice that promoted sustainability and ultimately led to supporting the prevention of health care-associated infections and patient harm.

How should we measure intraocular pressure in the era of coronavirus disease 2019? Balancing infectious risk, cleaning requirements, and accuracy

PURPOSE OF REVIEW

Accurate and precise measurement of intraocular pressure (IOP) is a vitally important component of the ophthalmic examination. There are multiple methods of tonometry, each of which has considerations in light of the ongoing severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic. This review discusses these considerations and compares various tonometer methods with the gold standard of Goldmann applanation tonometry (GAT).

RECENT FINDINGS

The SARS-CoV-2 virus may spread via droplets, microaerosols, or direct contact in the ophthalmology clinic. Tonometry poses a high risk of contamination. The accuracy and reliability of various methods of tonometry with single-use disposable equipment has been compared with Goldmann applanation tonometry.

SUMMARY

Goldmann applanation tonometry with disposable applanation tips, Tono-pen, and iCare employ single use tips to decrease the risk of cross-contamination of infectious agents. Review of the literature demonstrates good correlation between these devices and GAT, although the published level of agreement between devices varies.

How glaucoma care changed for the better after the pandemic

PURPOSE OF REVIEW

The current article reviews enhancements to the delivery of glaucoma care that developed in response to the coronavirus disease 19 (COVID-19) pandemic and are likely to persist beyond its resolution.

RECENT FINDINGS

Literature from the review period (2020-2021) includes reports highlighting contributions of the ophthalmology community to global health during the pandemic. Glaucoma practices worldwide have instituted more robust infection control measures to mitigate severe acute respiratory syndrome coronavirus 2 transmission in the outpatient setting, and many of these modifications will endure in the post-COVID era. Operational adjustments have led to the provision of more efficient glaucoma care. A hybrid care model involving technician-based diagnostic testing and subsequent virtual consultation with a glaucoma specialist has evolved as a useful adjunct to traditional face-to-face encounters with patients.

SUMMARY

Glaucoma specialists, patients, and staff have adapted to a 'new normal' of glaucoma care delivery during the COVID-19 pandemic. Although innovation has propelled several improvements to glaucoma care during this global health crisis, significant barriers to more widespread implementation of teleglaucoma still exist. Whether, and in what capacity, the pandemic has permanently altered glaucoma practice patterns remains to be seen.

The effectiveness of a three-step sterilization method for Goldmann tonometer prism: A cross-sectional study

Purpose:

To propose a three-step sterilization method for Goldmann tonometer prism (GTP) and to analyze the sterilization effects of each step.

Methods:

120 patients (240 eyes) who underwent Goldmann applanation tonometer (GAT) IOP measurement were enrolled in this study. GTPs were used individually for each patient and wiped by swabs soaked with 75% ethyl alcohol, ofloxacin eye drops, and 75% ethyl alcohol for at least 5 s. GTPs were directly pressed onto the surface of agar plates before (W0) and after three-step sterilization (W1, W2, and W3). All the agars were sent to the laboratory in 2 h and incubated at 37°C for 48 h. Subsequently, the growth of microbial species was assessed through visual inspection of the colonies at the inoculation points on the agar surface.

Results:

Staphylococcus. epidermidis was the most frequently isolated bacterium and was observed in 23.33% of all prisms. Most of the bacteria were eliminated at W3 except Staphylococcus. epidermidis and Kocuria roseus in one case. The isolation rates of Staphylococcus genus and Staphylococcus. epidermidis were significantly decreased (both with P < 0.001). The number of bacteria types isolated from prisms at time point W2 and W3 had a statistically significant difference compared with W1 and W (both with P < 0.05), while W2 and W3 exhibited no significant difference.

Conclusion:

This three-step sterilization method for GTP proved to be effective and safe for repeated use. We recommend using ofloxacin to prevent the transmission of pathogens based on ethyl alcohol, which could also bring some economic benefits.

Assessing the Reliability of Intraocular Pressure Measurements Using Rebound Tonometry

PRECIS

In a trio of prospective studies, the iCare rebound tonometer demonstrated significantly lower test-retest variability than Goldmann tonometry with good interoperator and interdevice reproducibility, supporting its value in monitoring intraocular pressure (IOP) changes over time.

PURPOSE

The purpose of this study was to characterize intraoperator and interoperator and interdevice reliability of IOP measurements with rebound tonometry (RT, ic100).

METHODS

Three prospective cross-sectional studies were conducted in distinct sample of adult patients with established glaucoma, suspected glaucoma, or no glaucoma at the West Virginia University Eye Institute. Participants in study 1 underwent 5 RT measurements in one randomly selected eye and 5 Goldmann tonometry measurements in the fellow eye by 1 operator; intraoperator variability was compared using the F test. In study 2, 3 operators each obtained 3 RT measurements in participants in randomized operator order. In study 3, a single operator collected 3 measurements each with 3 RTs in randomized device order. Between-operator and between-device reproducibility were characterized using intraclass correlation coefficients (ICCs).

RESULTS

Overall, 28, 19, and 25 subjects participated in the 3 respective studies. Within-subject variance across subjects was 0.757 in RT measurements and 2.471 in Goldmann measurements (P=0.0035). Interoperator reproducibility of RT measurements was good in both eyes [ICC for right eyes 0.78, 95% confidence interval (CI): 0.60-0.85; ICC for left eyes 0.75, 95% CI: 0.50-0.83]. Interdevice reproducibility of RT measurements was good approaching excellent (ICC for right eyes 0.87, 95% CI: 0.83-0.90; ICC for left eyes 0.89, 95% CI: 0.86-0.91).

CONCLUSIONS

The RT's lower measurement variability and good interoperator and interdevice reproducibility suggest that it can characterize IOP changes over time more robustly than Goldmann tonometry, aiding clinicians in assessing the effectiveness of glaucoma therapy and the consistency of IOP control.

The Tube Versus Trabeculectomy IRIS® Registry Study: Cohort Selection and Follow-up and Comparisons to the Randomized Controlled Trial

PURPOSE

To assess the feasibility of replicating a randomized controlled trial (RCT) with a cohort of eyes, from IRIS® Registry data, analogous to the Tube Versus Trabeculectomy (TVT) RCT cohort and compare characteristics and follow-up.

DESIGN

Comparison of RCT and IRIS Registry cohorts and follow-up.

METHODS

We identified a cohort of IRIS Registry eyes (2013-2017) that received either a glaucoma drainage implant (tube) or trabeculectomy after a previous trabeculectomy and/or cataract extraction; extracted clinical and demographic characteristics for baseline surgery and follow-up visits through 1 year; and compared treatment groups in the IRIS Registry cohort and this cohort to the TVT RCT cohort.

RESULTS

The IRIS Registry cohort included 419 eyes: 183 (43.7%) trabeculectomy; 236 (56.3%) tube. There were significant differences between treatment groups, including race (White: trabeculectomy 61.8%, tube 44.9%; Black: trabeculectomy 20.8%, tube 35.6%; P = .003) and the percentage of follow-up visits completed (trabeculectomy 88.4%, tube 83.8%, P = .004). There were also significant differences between the TVT IRIS Registry cohort and the TVT RCT cohort in the percentage of follow-up visits completed (IRIS Registry 85.6%, RCT 96.1%, P < .001) and in the probability of having a 1-year follow-up visit (IRIS Registry 81.4%, RCT 89.2%, P = .011).

CONCLUSION

The TVT IRIS Registry cohort had several significant treatment group differences at baseline, whereas there had been none in the TVT RCT cohort. Follow-up in the TVT IRIS Registry cohort was inferior to that of the TVT RCT. Some data needed to refine the selection of eyes for the cohort were not available in the IRIS Registry.

Guidelines and Recommendations for Tonometry Use during the COVID-19 Era

The novel coronavirus disease COVID-19 caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has resulted in a substantial change in eye care and clinical practice. There has been conflicting information and weak evidence on the virus's transmission through tears. Yet, virus detection on cornea and conjunctiva surface as a gateway for infection is not well-studied. Moreover, there have been no reported cases of SARS-CoV-2 transmission through tonometry to date. Thus, this uncertainty has urged this review on evidence-based guidelines and recommendations on tonometer use in the COVID-19 era. The aim of this article is to provide ophthalmologists with recommendations for tonometry practice based on current evidence and best practice guidelines.