Impact of referral refinement on management of glaucoma suspects in Australia

Which glaucoma patients benefit from 10-2 visual field testing? Proposing the functional vulnerability zone framework

CLINICAL RELEVANCE

A method for determining 10-2 deployment in glaucoma with the goal of detecting additional visual field sensitivity for the purpose of functional monitoring is proposed.

BACKGROUND

To provide a pilot method for determining when to deploy the 10-2 visual field (VF) test grid in glaucoma by characterising the 'functional vulnerability zone'.

METHODS

The cross-sectional 24-2 (central 12 locations) and 10-2 VF results from 133 eyes of 133 glaucoma subjects were used to describe the central Hill of Vision using VF sensitivity. The 'volume' (defined using arbitrary units, A.U.) under the Hill was calculated. A greater A.U. on the 10-2 indicated a functional vulnerability zone (FVZ), signifying additional clinical dynamic range for potential future monitoring. The main outcome measures were calculated A.U. and 24-2 factors which were significantly related to A.U. differences between 24-2 and 10-2.

RESULTS

Over 55% of patients had an FVZ (A.U. greater using 10-2). Several 24-2 features (worse mean deviation, worse central 24-2 mean defect, and a higher proportion of defective locations) were significant in the FVZ cohort compared to non-FVZ. 24-2 mean deviation levels at which 10-2 may be favoured were low at -3.16 to -3.62 dB. Specifically, 5 or more defective central 24-2 test locations were associated with an FVZ. Subjects exhibiting a less severe defect on the 10-2 were more likely to have an FVZ, indicating its potential for future VF monitoring.

CONCLUSIONS

The authors propose several clinical markers, focussing on the 24-2, which can guide clinicians on when the 10-2 may have utility in glaucoma assessment. The authors provide a pilot reference spreadsheet for clinicians to visualise the likelihood of 10-2 utility in the context of an FVZ.

Outcomes of newly referred patients with suspected angle closure: do we need to redefine the clinical pathways?

BACKGROUND/OBJECTIVES

To investigate outcomes of referrals for suspected angle closure and explore whether anterior segment optical coherence tomography (AS-OCT) can be used to tighten triaging criteria in a glaucoma virtual clinic.

SUBJECTS/METHODS

Retrospectively collected data. The first audit (04/2018-03/2019) identified referrals for suspected angle closure without other glaucoma-related findings (primary angle closure suspect (PACS) referrals). All patients underwent gonioscopy. The second audit (04-08/2019) identified patients with suspected angle closure in a virtual clinic. Management outcomes were assessed, using gonioscopy as reference standard. The outcomes of the second audit were re-audited after changing the triaging criterion from angle width <10° to iridotrabecular contact (ITC) in ≥1 quadrants on AS-OCT.

RESULTS

Out of 1754 glaucoma referrals (first audit), 24.6% (431/1754) were PACS referrals. Of these, only 10.7% (42/393) had an occludable angle on gonioscopy, with 97.6% (41/42) being PACS. Of these, 78% (32/41) underwent laser peripheral iridotomy. Out of 137 referrals in the virtual clinic (second audit), 66.4% (91/137) were triaged to the face-to-face clinic. Of these, 31.9% (29/91) were discharged. AS-OCT had positive and negative predictive value of 74.3% (95% confidence intervals (CI) 57.8-86.0) and 82.1% (95% CI 70.0-90.2%), respectively, in detecting ITC in ≥1 quadrants. In the re-audit 45.9% (45/98) of those with suspected angle closure were triaged for gonioscopy, with 24.4% (11/45) of them being discharged.

CONCLUSION

PACS referrals represent a substantial burden to hospital-based services and their accuracy is low. ITC in ≥1 quadrants on AS-OCT can be useful in triaging those who need further evaluation with gonioscopy.

The effectiveness of interventions for optometric referrals into the hospital eye service: A review

PURPOSE

Ophthalmic services are currently under considerable stress; in the UK, ophthalmology departments have the highest number of outpatient appointments of any department within the National Health Service. Recognising the need for intervention, several approaches have been trialled to tackle the high numbers of false-positive referrals initiated in primary care and seen face to face within the hospital eye service (HES). In this mixed-methods narrative synthesis, we explored interventions based on their clinical impact, cost and acceptability to determine whether they are clinically effective, safe and sustainable. A systematic literature search of PubMed, MEDLINE and CINAHL, guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), was used to identify appropriate studies published between December 2001 and December 2022.

RECENT FINDINGS

A total of 55 studies were reviewed. Four main interventions were assessed, where two studies covered more than one type: training and guidelines (n = 8), referral filtering schemes (n = 32), asynchronous teleophthalmology (n = 13) and synchronous teleophthalmology (n = 5). All four approaches demonstrated effectiveness for reducing false-positive referrals to the HES. There was sufficient evidence for stakeholder acceptance and cost-effectiveness of referral filtering schemes; however, cost comparisons involved assumptions. Referral filtering and asynchronous teleophthalmology reported moderate levels of false-negative cases (2%-20%), defined as discharged patients requiring HES monitoring.

SUMMARY

The effectiveness of interventions varied depending on which outcome and stakeholder was considered. More studies are required to explore stakeholder opinions around all interventions. In order to maximise clinical safety, it may be appropriate to combine more than one approach, such as referral filtering schemes with virtual review of discharged patients to assess the rate of false-negative cases. The implementation of a successful intervention is more complex than a 'one-size-fits-all' approach and there is potential space for newer types of interventions, such as artificial intelligence clinical support systems within the referral pathway.

Implementation and scalability of shared care models for chronic eye disease: a realist assessment informed by health system stakeholders in Finland, the United Kingdom, and Australia

BACKGROUND/OBJECTIVES

Several health systems have implemented innovative models of care which share the management of patients with chronic eye diseases between ophthalmologists and optometrists. These models have demonstrated positive outcomes for health systems including increased access for patients, service efficiency and cost-savings. This study aims to understand factors which support successful implementation and scalability of these models of care.

SUBJECTS/METHODS

Semi-structured interviews were conducted with 21 key health system stakeholders (clinicians, managers, administrators, policy-makers) in Finland, United Kingdom and Australia between October 2018 and February 2020. Data were analyzed using a realist framework to identify the contexts, mechanisms of action, and outcomes of sustained and emerging shared care schemes.

RESULTS

Five key themes relating to successful implementation of shared care were identified as (1) clinician-led solutions, (2) redistributing teams, (3) building inter-disciplinary trust, (4) using evidence for buy-in, and (5) standardized care protocols. Scalability was found to be supported by (6) financial incentives, (7) integrated information systems, (8) local governance, and (9) a need for evidence of longer-term health and economic benefits.

CONCLUSIONS

The themes and program theories presented in this paper should be considered when testing and scaling shared eye care schemes to optimize benefits and promote sustainability.

Assessment of optometrists' referral accuracy and contributing factors: A review

PURPOSE

In the UK, ophthalmology has the highest number of outpatient appointments within the National Health Service. False-positive referrals from primary care are one of the main factors contributing to the oversubscription of hospital eye services (HESs). We reviewed the accuracy of referrals originating from primary care optometrists and contributing factors, such as condition type and years since registration.

RECENT FINDINGS

Of the 31 studies included in the review, 22 were retrospective analyses of referrals and appointments at the HES. Eight were prospective studies, and one used online clinical vignettes. Seven assessed the accuracy of referrals for all ocular conditions. The remaining studies focused on glaucoma (n = 11), cataracts (n = 7), emergency conditions (n = 4), neovascular age-related macular degeneration (n = 1) and paediatric binocular vision (n = 1). The diagnostic agreement for suspected emergency ocular conditions was the lowest, with only 21.1% of referrals considered to require urgent attention in one study. For glaucoma, the first-visit discharge rate was high (16.7%-48%). Optometrist referral accuracy was overall 18.6% higher than General Medical Practitioners'; however, the two mainly referred different ocular conditions. Female optometrists made more false-positive referrals than males (p = 0.008). The proportion of false positives decreased by 6.2% per year since registration (p < 0.001).

SUMMARY

There was significant variation in referral accuracy across different ocular conditions, partly due to differences when defining accurate referrals. Optometrists working in primary care are generally more limited in their resources than the HES. Thus, choosing the cautious option of referral when they are unsure could be in the patients' best interests. The possible effect of increased use of advanced imaging on referrals requires evaluation. Although interventions such as refinement schemes have been put in place, these vary across regions, and their approaches such as virtual referral triaging may reduce unnecessary HES face-to-face appointments and promote communication between primary and secondary care.

Feasibility of providing collaborative glaucoma care from a community optometry perspective: a mixed-methods assessment

CLINICAL RELEVANCE

Despite evidence showing that optometry-led collaborative glaucoma care can be delivered at reduced cost compared to ophthalmology-based care without compromising patient outcomes, such models of care are not widely practiced in Australia. Ensuring glaucoma patients have equitable access to effective and cost-effective care is a matter of public health importance.

BACKGROUND

This study examined the feasibility and business case assessment for providing glaucoma care from a community optometry perspective.

METHODS

Nine optometrists were interviewed in a semi-structured format, focusing on the economic feasibility, barriers, and benefits of collaborative glaucoma care. The Consolidated Framework for Intervention Research was used for thematic data analysis. Costs and revenues associated with providing glaucoma care were sourced from the literature and interviews. A business case model assessing the profitability of glaucoma care in optometric practice was developed.

RESULTS

Thematic analysis revealed concerns over financial viability such that current Medicare Benefits Schedule fees are not sufficient to justify the cost of running a community optometry glaucoma clinic. All participants received a supplementary source of revenue. This finding was confirmed by the business case assessment. Inter-professional trust was perceived to be a key barrier to initiation of collaborative care however was able to be overcome quickly upon commencement of a collaborative care relationship. Optometrists perceived that collaborative care was beneficial to all involved, including patients, ophthalmologists, optometrists, and health payers. There was a perception of a growing divide between clinical and retail optometry, which was thought by most participants to be appropriate.

CONCLUSION

This study is the first to explore the feasibility and business case for community-based optometrists to provide collaborative glaucoma care in Australia. Our findings show that current public funding is insufficient to justify the business case to private optometry practice, despite being perceived by optometrists as beneficial to all involved.

Referrals from community optometrists in England and their replies: A mixed methods study

PURPOSE

Community optometrists, through routine eye examinations, identify patients with disease or ocular abnormalities requiring referral to the Hospital Eye Service. In many cases no reply to the referral letter is received, resulting in some patients being re-referred unnecessarily, potentially increasing the number of other patients who lose sight whilst on hospital waiting lists. This study investigated, qualitatively and quantitatively, factors influencing optometric referrals and replies.

METHODS

The three-phase, sequential mixed methods study started with a literature review and qualitative phase, interviewing stakeholders to identify issues for exploration in subsequent phases. The second, quantitative phase, undertook documentary analysis of 349 patient referral records from three optometric practice modalities (domiciliary, independently owned, and corporate chain) in England. A final qualitative phase obtained views from stakeholders to explore unexplained findings from the first two phases.

RESULTS

Phase 1 identified communication, financial, professional and technological issues for further exploration. In Phase 2, the referral rate was 22.2% for domiciliary provider, 2.1% for independent practice and 2.5% for the corporate chain, with the variation most likely explained by patient age and associated ophthalmic disease, illness and disability. The referral reply rate was 5.7% for domiciliary provider, 25.0% for independent practice and 4.9% for the corporate chain. The community optometrist remained unaware of the outcome of their referral in 72.8% of cases. Qualitative analyses indicate the main factors influencing referral reply rates are technology, the General Medical Practitioner, community optometrists' utility to and utility of the National Health Service and patient mobilisation.

CONCLUSIONS

The low referral reply rate creates a break in the feedback loop required to raise the standard of referrals and avoid unnecessary re-referral. Of the factors identified that influence referral reply rates, technology is key in view of the increasing use of online referral platforms. Feedback to the referring optometrist should be embedded in such systems.

Glaucoma Suspects: The Impact of Risk Factor-Driven Review Periods on Clinical Load, Diagnoses, and Healthcare Costs

Purpose

To model the healthcare impact (clinical attendance time and financial cost) and clinical outcomes (glaucoma diagnoses) of different risk factor–driven review frequencies for glaucoma suspect patients up until the point of discharge or diagnosis.

Methods

Medical records of 494 glaucoma suspects were examined to extract the clinical diagnosis. Two criteria for review periods were defined, based on contrasting stringency from established clinical guidelines: American Academy of Ophthalmology (AAO), more stringent/less frequent; and the Australian National Health and Medical Research Council (NHMRC), less stringent/more frequent. We used these data to model patient outcomes and healthcare costs using a Markov model.

Results

The less stringent/more frequent criterion resulted in more high-risk glaucoma suspects requiring more frequent review compared with the more stringent/less frequent criterion. Across the 15 Markov cycles (7.5 years), the less stringent/more frequent review criterion resulted in 6.6% more diagnoses and fewer overall clinical visits (14.7%) and reduced cost per diagnosis by 12% to 32% (P < 0.0001). The number of glaucoma diagnoses made using each criterion converged at 2.5 to 3 years.

Conclusions

The stringency of risk assessments for glaucoma suspects impacts review periods and therefore clinical load, healthcare costs, and diagnosis rates. Using current testing methods, more frequent review periods appear advantageous for diagnostic efficiency, with both lower clinic load and lower cost up until the point of discharge or glaucoma diagnosis.

Translational Relevance

A less stringent criterion for assessing the risk of developing glaucoma potentially offers a more cost-effective method for reviewing glaucoma suspects, especially within the first 2.5 years.

A prospective study on effectiveness of elevated intraocular pressure as a criterion for glaucoma referrals by optometric practitioners in Sweden

PURPOSE

To evaluate the outcome of referrals for suspected glaucoma based on elevated intraocular pressure (IOP) made by optometric practitioners in Sweden.

METHODS

This prospective study included 95 individuals referred to the Skåne University Hospital Malmö, Sweden, during 2019, by optometric practitioners, based on elevated IOP. Positive outcome was defined as a diagnosis of glaucoma, or a diagnosis of suspected glaucoma. Referral accuracy was analysed. Positive predictive values (PPV) of different hypothetical IOP and age thresholds were calculated.

RESULTS

In 34% (95% CI: 24-43%) of the referrals, no eye disease was found. Intraocular pressure (IOP) was the only referral criterion in 77% (73/95). The PPV was 35% (95% CI: 25-45%) for all referrals, 27% (95% CI: 16-38%) for IOP-only referrals and 59% (95% CI: 36-82%) for referrals including additional findings. In IOP-only referrals, no definite diagnosis of glaucoma was made in any patients <45 years of age. Applying a theoretical age limit of ≥45 years with a hypothetical IOP limit of ≥25 mmHg in patients 45-69 years and of ≥22 mmHg in patients ≥70 years increased the PPV to 42% (95% CI: 27-57%). IOP-only referrals would have been reduced by 27% without missing any glaucoma cases.

CONCLUSION

The overall predictive value of the referrals was poor. Glaucoma resources would have been used more effectively by increasing the required age for IOP-only referrals to ≥45 years in combination with different IOP thresholds for certain age groups.

Review of referrals reveal the impact of referral content on the triage and management of ophthalmology wait lists

OBJECTIVES

Many chronic eye conditions are managed within public hospital ophthalmology clinics resulting in encumbered wait lists. Integrated care schemes can increase system capacity. In order to direct implementation of a public hospital-based integrated eye care model, this study aims to evaluate the quality of referrals for new patients through information content, assess triage decisions of newly referred patients and evaluate the consistency of referral content for new patients referred multiple times.

DESIGN

A retrospective and prospective review of all referral forms for new patients referred to a public hospital ophthalmology clinic between January 2016 and September 2017, and September 2017 and August 2018, respectively.

SETTING

A referral-only public hospital ophthalmology clinic in metropolitan Sydney, Australia.

PARTICIPANTS

418 new patients on existing non-urgent wait lists waiting to be allocated an initial appointment, and 528 patients who were newly referred.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was the information content of referrals for new patients. The secondary outcomes were triage outcomes for new incoming referrals, and the number of new patients with multiple referrals.

RESULTS

Of the wait-listed referrals, 0.2% were complete in referral content compared with 9.8% of new incoming referrals (p<0.001). Of new incoming referrals, 56.7% were triaged to a non-urgent clinic. Multiple referrals were received for 49 patients, with no change in the amount of referral content.

CONCLUSIONS

Most referrals were incomplete in content, leading to triage based on limited clinical information. Some new patients were referred multiple times with their second referral containing a similar amount of content as their first. Lengthy wait lists could be prevented by improving administrative processes and communication between the referral centre and referrers. The future implementation of an integrated eye care model at the study setting could sustainably cut wait lists for patients with chronic eye conditions.

Effectiveness of Elevated Intraocular Pressure as a Criterion for Glaucoma Referral After 6 Years of Follow-Up

Purpose

To evaluate the long-term predictive value of the need to treat patients referred by optometric practitioners, regarding glaucoma, in Malmö, Sweden, using intraocular pressure (IOP) as the primary referral criterion.

Patients and Methods

This retrospective study included 94 of 108 (87%) individuals referred to the Skåne University Hospital in Malmö, Sweden, for elevated IOP during 2012–2013. Data were extracted from patient records by the end of 2019. Positive outcome was defined as glaucoma, treated suspected glaucoma or treated ocular hypertension (OH) at referral or during the follow-up period. Positive predictive values (PPV) were calculated using different hypothetical thresholds for age and IOP-levels. Long-term follow-up was used to evaluate whether the first visit diagnoses would change over time, and if this would affect the effectiveness of the referrals.

Results

Elevated IOP was the only referral criterion in 84% (n=79). In 28 patients (35%) among the IOP-only referrals, no ocular disease was found, and 26 patients (33%) had a positive outcome at the first visit. Median follow-up time was 6.4 years. PPV according to diagnosis after follow-up was 42% (95% CI: 32–54%) for IOP-only referrals. Including thresholds of ≥45 years of age in combination with an IOP of ≥25 mmHg in the referral criteria would have reduced the number of IOP-only referrals by 27% (21 of 79), and increased the PPV to 57% (95% CI: 45–71%) at the last visit. No positive outcome would have been missed, among those that were followed-up after the first visit, when applying these thresholds for referral, over a follow-up period of six years.

Conclusion

Using only elevated IOP as referral criterion showed a poor accuracy for predicting those that require IOP lowering treatment. The long-term follow-up allowed us to verify the applicability of higher hypothetical threshold requirements on age and IOP for glaucoma referrals from optometric practices.

Clinical outcomes of the Centre for Eye Health: an intra-professional optometry-led collaborative eye care clinic in Australia

Clinical relevance: This novel clinical model is the first of its kind in Australia and was designed to help reduce unnecessary referrals into overburdened public systems by utilising pre-existing community-based resources.Background: The Centre for Eye Health (CFEH) is an intra-professional optometry-led care clinic offering an alternative pathway to traditional ophthalmology-based pathways (public hospital clinics or private practices) for 'at-risk' patients requiring ocular imaging, diagnostic and management services. This study evaluates the CFEH integrated eye-care model in the identification of chronic eye diseases within the community.Methods: A retrospective random clinical audit of over 750 medical records of patients referred to the CFEH between July 2016 and June 2019 was conducted. Demographics of patients, referral type, final diagnosis and recommended management plans were extracted from this subset. Clinic key performance indicators (referral turnaround time, and net cost per patient appointment) were also extracted.Results: Of the 755 referrals associated with the audited records, 77.4% resulted in the identification of patients with or at-risk of developing eye diseases with 73.5% of this cohort requiring ongoing monitoring at CFEH or referral to ophthalmology. Although the CFEH model is not designed to diagnose or manage acute conditions, 1.5% of patients in this pathway required same day ophthalmological or medical intervention. The cost per patient was equivalent to hospital eye departments costs.Conclusion: This integrated care pathway has the potential to reduce unnecessary referrals from optometrists to hospital ophthalmological service by offering a safe and effective alternate pathway. The majority of patients seen within this pathway were able to be monitored within optometry-led services. This is a unique clinical model utilising inter-professional referrals within optometry which has the potential to reduce preventable blindness within the community through the early detection of eye diseases.