It is estimated that approximately 300,000 Australians have glaucoma, however only 50% have been diagnosed.1 There is also a large portion of Australians who are glaucoma suspects of some description. Identifying these patients and ensuring they receive time-sensitive and appropriate care can be a challenge.
As of October 2019, there were 5,600 practising optometrists registered with the Optometry Board of Australia (OBA);2 and as of 2016, there were just over 900 accredited ophthalmologists practising in Australia.3
With the rapid growth and aging nature of the Australian population, the incidence of glaucoma is expected to increase. Collaborative care between optometrists and ophthalmologists provides the opportunity to detect disease in a timely manner, ensure appropriate monitoring and review systems are in place and, above all else, prioritise patient-focussed care and treatment.
COLLABORATIVE CARE: WHERE ARE WE NOW?
The goal of collaborative care in glaucoma management, above all else, is to optimise patient care and patient outcomes. At the current time, there are guidelines endorsed by the Royal Australian and New Zealand College of Ophthalmology (RANZCO) outlining the core principles of collaborative care4 and detailing what a suitable referral pathway might look like (Figure 4).5 As shown in Figure 4, the pathway proposes that low-risk glaucoma suspects can be primarily monitored by optometrists, whereas high-risk glaucoma suspects and early-to-moderate primary open angle glaucoma (POAG) patients should, at the very least, have an initial ophthalmology assessment, and thereafter intermittent reviews with an ophthalmologist depending on their risk of lifetime vision loss. The ophthalmologist can then determine the need for treatment (including a discussion around all possible treatment options, ranging from medication to laser and surgical interventions) as well as assess the patient’s suitability for a collaborative care model. Advanced, acute or unstable glaucoma has been considered “not usually suitable for collaborative care”.5
The goal of collaborative care in glaucoma management above all else is to optimise patient care and patient outcomes
Collaborative Care in Action
IOPs were measured with Goldmann applanation tonometry (GAT) and found to be 18mmHg in the right eye and 23mmHg in the left eye. Pachymetry was 506 microns in the right, and 511 microns in the left. There was a known family history of glaucoma (the patient’s mother had been diagnosed in her 60s, and her older brother was being monitored as a glaucoma suspect at the time). Humphrey visual field testing was performed and showed an early superior arcuate scotoma in the left eye (less than 6db and not within 10 degrees of fixation), whereas the right field was normal (Figure 3). Gonioscopy showed open angles in each eye and there was no evidence of pseudoexfoliation syndrome or pigment dispersion syndrome.
In view of the family history, the patient’s young age, and the structural and functional findings, a decision was made to commence treatment in the form of once-daily topical hypotensive medication to both eyes. The target pressure was set as 13mmHg in the right eye and 15mmHg in the left, and this was successfully achieved at a pressure check arranged for six weeks later. The patient subsequently had two six month follow up visits with her ophthalmologist, during which all disc and visual field findings were stable, and the IOPs within target range. A collaborative care model was discussed with the patient. She subsequently agreed to being reviewed on a six monthly basis, alternating between her optometrist and ophthalmologist. A letter was sent to the referring optometrist regarding this plan, and it was indicated that any significant changes in pressure, optic disc appearance (including increased cupping or Drance haemorrhage), field progression or intolerance to medication would warrant earlier ophthalmological review.
Figure 1. Red-green composite photographs of the optic nerve heads using Optos 200Tx ResMax imaging (Optos plc.). Note the asymmetry in the cup-disc ratios between the two eyes, and the thinning of the supero- and infero-temporal rims of the left optic disc. There was also mild asymmetry between the disc sizes (vertical disc diameters of 1.82mm in the right eye, and 1.98mm in the left).
For collaborative care models to be successful and patient-focussed, White and Goldberg6 highlighted the need for “clear lines of communication” (preferably in written form) between optometrists and ophthalmologists. Clinical information, such as review periods, target pressures, treatment plans (both short and long-term), and structural or functional changes which would warrant earlier ophthalmology review, should be included. This case study represents POAG which was fortunately stabilised at an early stage with treatment. Given this, and in accordance with the current guidelines and referral pathway, it was suitable for the patient to enter into a collaborative care plan in which all clinical information was openly shared. Similar collaborative care schemes have had success overseas in countries such as Canada, New Zealand, and the United Kingdom.6,7 In the Australian context, the advantages of collaborative care may be even more evident. Collaborative care is particularly well-placed to help tackle the geographic barriers that patients face when accessing specialist care and may help mitigate costs to the patients and the healthcare system as a whole. Collaborative care can potentially improve outcomes for glaucoma patients over the longer-term by breaking down these barriers.
POTENTIAL BARRIERS TO COLLABORATIVE CARE
While there are certainly advantages to collaborative care models, perceived barriers at the current time include practitioners’ access to diagnostic equipment, variability between different equipment and machines, practitioner skill and knowledge (as well as their desire to participate in collaborative care schemes) and, as mentioned above, ensuring there are reliable and confidential systems in place for communication and transfer of information.
Collaborative care is particularly well-placed to help tackle the geographic barriers that patients face when accessing specialist care and may help mitigate the costs to the patients and the healthcare system as a whole
Figure 2. Retinal nerve fibre layer (RNFL) analysis of the optic discs using HRA+OCT Spectralis (Heidelberg Engineering). Right eye data is displayed on the left, and left eye data on the right. There is borderline thinning, particularly of the inferotemporal sector of the left optic disc, and asymmetry of the mean RNFL measurements (95 microns in the right eye versus 79 microns in the left).
White and Goldberg6 proposed that optometrists who are involved in collaborative care glaucoma models should have access to, and demonstrate proficiency in, Goldmann applanation tonometry (GAT), pachymetry, disc imaging, full-threshold visual field testing, and preferably gonioscopy and optical coherence tomography (OCT), amongst others. GAT has long been considered the gold standard for IOP measurement – non-contact tonometry is known to be strongly influenced by central corneal thickness (CCT) and is prone to over-estimating IOPs.8 Rebound tonometry can similarly over-estimate high IOPs, and values can be significantly affected if measurements are taken off-axis.8
Visual field testing has historically been readily available in many optometry practices, however there are various manufacturers of automated perimeters as well as different testing strategies. Generally speaking, field results from different machines and/or based on different testing strategies are not directly comparable. Similarly, OCT technology is becoming increasingly commonplace in optometry practices but retinal nerve fibre layer (RNFL) measurements can vary significantly across different OCT devices. Diagnostic testing also can be associated with poor reliability indices (as is the case with visual field testing, especially on initial attempts) and poor specificity/high false positives.6 In these situations, it can be the progression of structural findings or functional results that alerts a practitioner to the presence of glaucomatous disease.
Figure 3. SITA Faster 24-2 results on the Humphrey Field Analyser 3 (HFA3) showing a full field in the right eye, and an early superior arcuate defect in the left eye. The central 10 degrees of the visual field in the left eye have been marked with a blue box. Note there are no defects in this region greater than 6dB.
Optometrists and ophthalmologists who are participating in collaborative care schemes would ideally have the same visual field and OCT machines for longitudinal monitoring and comparisons. Even if this were the case, however, glaucoma practitioners rely greatly on the ability of the field tests and OCT to predict the rate of vision loss over time. This requires the cumulative data for each patient to be analysed within one system (having six monthly scans done at the optometrist and then at the ophthalmologist halves the usable data points for analysis). Practitioners, industry and regulatory agencies all need to work together to find solutions to this barrier.
Additionally, of the 5,600 optometrists currently registered with the OBA, 62.8% (approximately 3,500) are therapeuticallyendorsed. 2 Some of these optometrists have completed further training in the management of glaucoma through courses offered by universities or other educational providers. There is, therefore, significant variation between optometrists with respect to skill and knowledge of glaucoma co-management. Moreover, the desire to participate in a collaborative care scheme differs greatly between practitioners.
Currently, optometrists and ophthalmologists who practice geographically close to one another have ad hoc discussions regarding preferences on collaborative care. The authors believe it would be useful to establish a national database of optometrists and their qualifications, as well as their interest in glaucoma co-management and access to diagnostic and imaging equipment, to better facilitate collaborative care models between practitioners.
Finally, various legal hurdles exist which are unique to collaborative care models. These include the complex interplay of shared care and shared responsibility. We have yet to have clear guidance as to how medical indemnity will adapt to the new paradigm. Patient consent will also be needed, both in terms of sharing their health information amongst practitioners (which entails privacy considerations) as well as their willingness to accept that their care will be divided between healthcare providers.
NEXT STEPS
NEXT STEPSCollaborative care in glaucoma will likely become increasingly common in Australia. The benefits and effectiveness of such models should be assessed periodically, both with respect to economic impact and to determine if there is measurable improvement in patient outcomes such as adherence to reviews and treatment regimes. This will validate the theorised benefit of collaborative care and allow for refinement of policies and guidelines. Not-for-profit organisations like Glaucoma Australia are already encouraging referrals of glaucoma patients into a standardised national database.1 Historically, Glaucoma Australia provides invaluable educational services, support and information for practitioners and patients alike, however the organisation also plays a role in facilitating communication between optometrists and ophthalmologists and could certainly provide a means of monitoring the benefits of collaborative care.
it would be useful to establish a national database of optometrists and their qualifications, as well as their interest in glaucoma comanagement and access to diagnostic and imaging equipment
It is also largely recognised that there is maldistribution of eye care practitioners throughout Australia – approximately 83% of ophthalmologists are located in major capital cities,3 and similarly, over three-quarters of optometrists practise in metropolitan areas.9 Patients in rural and regional Australia could, unfortunately, have delayed access to care. Collaborative care in these locations plays a paramount role in ensuring patients are assessed by a suitable practitioner in a timely fashion. Telehealth (or teleglaucoma), in which patient information and imaging is confidentially transferred through the Internet, will almost certainly play a significant role in collaborative care in these situations. Kassam and colleagues10 reviewed the success of a teleglaucoma system in Western Australia, which allowed for real-time discussion between a regionallylocated provider, the patient and an ophthalmologist, thereby providing prompt assessment and initiation of treatment for patients who required this. This model or similar may be one to adopt in other regional or remote parts of Australia.
SUMMARY
One could hypothesise what would constitute an ideal collaborative glaucoma system. In essence, this would be a system that is easy for patients and healthcare providers to navigate, one that desegregates the public and private systems, and one that reduces the overall cost to society. Additionally, the ideal system would be one that automates the reliable and confidential transfer of data between collaborative partners, and one that has a high fidelity for detecting and treating disease.
Although we have come a long way in glaucoma co-management, and we are already making significant inroads to broadening access to glaucoma care in Australia, there are still many foreseen and unforeseen challenges ahead. Now may be an ideal time for us to take stock of where we are and where we are heading. Data is needed to assess the effectiveness of the various collaborative care programs being implemented, as well as to guide us on where they are of most benefit. Similarly, there is a need for agreed upon processes that help tackle the barriers, such as effective communication, technology and consent. Perhaps by grappling with these thorny issues we may move closer to that ideal of seamless glaucoma care for all Australians.
Inez Hsing BAppSc(Optom)(Hons), GradCertOcTher, graduated from QUT in 2008 with First Class Honours and a University Medal. She was also awarded the Optometry Australia (QLD & NT Division) Clinical Excellence Award, and completed a Graduate Certificate in Ocular Therapeutics in 2013. Ms Hsing has worked as a clinical optometrist in private ophthalmology practice since 2013 and is currently based at the OKKO Eye Specialist Centre, Brisbane. She is also active in training optometry students as a Clinical Supervisor in the QUT School of Optometry’s primary care clinics. Ms Hsing joined the Glaucoma Australia Optometry Committee in 2017 and is passionate about early detection and education of glaucoma in the general community.
Dr Nick Toalster MBBS(Hons), FRANZCO is an ophthalmologist who sub-specialises in cataract, cornea and glaucoma. He completed degrees in both optometry as well as medicine and surgery, both with honours, at the Queensland University of Technology and University of Queensland, respectively. Dr Toalster trained as an ophthalmologist in Sydney and worked in indigenous communities in the Northern Territory right through to rural New South Wales, as well as in a number of major hospitals in Sydney and Melbourne. He completed subspecialty fellowships in glaucoma, cornea and anterior segment disease. As both an optometrist and an ophthalmologist Dr Toalster is particularly well placed to understand the emerging field of eye disease co-management, having been involved with glaucoma comanagement programs run through the Royal Victorian Eye & Ear Hospital and helping establish the program at the Royal Brisbane & Women’s Hospital. Dr Toalster is currently based at the OKKO Eye Specialist Centre, Brisbane, and is a Consultant at the Royal Brisbane & Women’s Hospital (RBWH).
References
- Glaucoma Australia. Glaucoma Australia launches a bold new referral response intervention [Internet]. New South Wales, 2018 [updated 21 June 2018, cited 29 December 2018]. Available from: www.glaucoma.org.au/articles/ glaucoma-australia-launches-a-bold-new-referral-responseintervention- article/?sch=1178&kw=referral%20pathway.
- AHPRA Optometry Board of Australia. Optometry Board of Australia: Registrant Data. 31 October 2019. Available from: www.optometryboard.gov.au/About/Statistics.aspx
- Australian Government Department of Health. Ophthalmology: 2016 Facstheet [Internet]. October 2017. Available from: https://hwd.health.gov.au/webapi/ customer/documents/factsheets/2016/Ophthalmology.pdf
- RANZCO. Principles for Collaborative Care of Glaucoma Patients [Internet]. Surry Hills (NSW); 2015. Available from: ranzco.edu/wp-content/uploads/2018/11/Guidelines-forcollaborative- care-of-glaucoma-patients-1.pdf
- RANZCO. RANZCO Referral Pathway for Glaucoma Management [Internet]. 2019. Available from: ranzco.edu/ wp-content/uploads/2019/06/RANZCO-Referral-Pathwayfor- Glaucoma-Management.pdf.
- White A, Goldberg I. Guidelines for the collaborative care of glaucoma patients and suspects by ophthalmologists and optometrists in Australia. Clinical & Experimental Ophthalmology 2014; 42(2):107-117.
- Botha VE, Ah-Chan J, Taylor SK, Wang P. Collaborative glaucoma care. Clinical & Experimental Ophthalmology 2015; 43(5):480-483.
- Resende AF, Yung ES, Waisbourd M, Katz LJ. Monitoring intra ocular pressure in glaucoma: current recommendations and emerging cutting-edge technologies. Expert Review of Ophthalmology 2015; 10(6):563-576.
- Australia Optometry. POSITION STATEMENT: The optometry workforce in Australia [Internet]. June 2017. Available from: www.optometry.org.au/wp-content/ uploads/POSITION-STATEMENT-The-Optometry- Workforce-May-2017.pdf
- Kassam F, Yogesan K, Sogbesan E, Pasquale LR, Damji KF. Teleglaucoma: improving access and efficiency for glaucoma care. Middle East African Journal of Ophthalmology 2013; 20(2): 142-149.
