Evaluating referrals of flashing lights and floaters coming into secondary care from primary care

CLINICAL RELEVANCE

Optometrists should look to take every opportunity to expand their knowledge, understanding and skills pertaining to vitreoretinal conditions.

BACKGROUND

Despite the existence of acute eye care schemes and the up-skilling of optometrists, many units are still noticing large numbers of poor-quality referrals with high false positive rates. The authors pondered whether these schemes are effective.

METHODS

At two different time points, a prospective analysis of patients took place, of all the flashing lights and floaters referrals coming into secondary care at the Royal Glamorgan Hospital, Wales, UK. The following data was captured: the exact source of the primary care referral, the diagnosis being queried, the secondary care diagnoses made and the secondary care management decisions. The accuracy of retinal break and Shafer's sign detection were also directly compared between primary care and secondary care using Cohen's Kappa Coefficient.

RESULTS

For the 2018 period, n = 51 patients were included. For the 2022-23 period n = 100 patients were included. The majority of referrals during both periods were from optometrists (>80%) via the WECS pathway. The most common diagnoses being queried were retinal breaks (~50%), followed by retinal detachments (~20%). Interestingly up to 20% of patients seen in secondary care were diagnosed as normal examinations and ~ 20%. Over 1/3 of patients were discharged after their first visit to the EEC. Statistically significant differences were found between the accuracy of retinal tear and Shafer's identification between the primary and secondary care settings.

CONCLUSION

A high number of false positive referrals are coming into secondary care from the WECS pathway and clear training and education needs have been identified.

The value of virtual glaucoma clinics: a review

Virtual clinics are being utilised to tackle the growing demand for glaucoma healthcare. We conducted a literature search on 28 February 2023 using MEDLINE (PubMed), EMBASE and Web of Science databases. We searched for studies on virtual glaucoma clinics, published in the English language between 2000 and 2023. Studies suggest that virtual glaucoma clinics are a safe and effective alternative to traditional face-to-face clinics for patients with stable and early-to-moderate glaucoma. Patient satisfaction is high across all clinics surveyed. Satisfaction appears to be linked to good communication, trust and improved waiting times. The majority of healthcare professionals are also content with virtual glaucoma clinics. There are no dedicated cost-benefit analyses for virtual glaucoma clinics in the UK. However, virtual clinics in other specialties have reported significant cost savings.

Repeatability and agreement of central corneal thickness measurements with a new handheld non-contact pachymeter

PURPOSE

To compare the repeatability of central corneal thickness (CCT) measurements taken with a new handheld pachymeter (Occuity PM1 pachymeter) and to assess its agreement with ultrasound biometry and two commercially available optical biometers in participants with normal eyes.

METHODS

Three consecutive CCT measurements of the right eye of 105 participants with normal corneas were acquired by the PM1 pachymeter, Lenstar LS 900 and Oculus Pentacam HR in a random order. This was followed by three measurements with a handheld ultrasound pachymeter (UP) (Pachmate 2). Repeatability and the repeatability limit were calculated for each device and Bland-Altman limits of agreement (LoA) were determined for the PM1 pachymeter compared to the other devices.

RESULTS

The mean CCT (±SD) was 551.04 ± 33.43, 558.62 ± 31.46, 549.41 ± 31.00 and 539.73 ± 29.50 μm for the PM1 pachymeter, UP, Lenstar and Pentacam, respectively. The repeatability limits (expressed as the within subject SD for repeat measurements) were 14.02, 13.68, 4.99 and 9.90 μm, respectively. The closest agreement was between the PM1 and Lenstar (mean difference = -1.63 μm with LoA 10.72 μm below and 13.97 μm above the readings obtained with the Lenstar). The PM1 underestimated CCT compared to UP (mean difference = 7.58 μm, LoA 24.63 μm below and 9.47 μm above UP). The agreement was lowest between the PM1 and Pentacam (mean difference = -11.30 μm, LoA between 4.29 and 26.89 μm).

CONCLUSIONS

The PM1 pachymeter shows excellent precision for CCT measurements across a range of corneal thicknesses in normal eyes and provides a safe and easy-to-use alternative to ultrasound pachymetry.

Profiling and factors associated with glaucoma diagnostic practice in sub-Saharan Africa-a cross sectional study of Nigerian and Ghanaian optometrists

BACKGROUND

Ghana and Nigeria are the two countries in Africa that currently run the Doctor of Optometry (OD) program in sub-Saharan Africa (SSA). Optometrists in these countries are licensed to provide glaucoma care. Despite the clinically relevant practice guidelines for glaucoma, there is no data on the practice patterns for glaucoma eye care in SSA, a region with the highest prevalence of glaucoma. This study aimed to profile glaucoma diagnosis adherence to practice guidelines among optometrists in two neighbouring anglophone countries (Nigeria and Ghana).

METHODS

A web-based cross-sectional survey of practising optometrists was conducted in both countries. Each country data was weighted to reflect the total number of licensed and practising optometrists at the time of this survey. Descriptive analyses were performed against demography and practice factors using survey commands to adjust for sampling weights when estimating confidence intervals (CI) around prevalence estimates. Simple and multiple logistic regression analyses were performed to identify factors associated with glaucoma diagnosis.

RESULTS

A total of 493 optometrists (238, 48.3% and 255, 51.7%) from Ghana and Nigeria respectively, responded to the survey-the first to document and compare the glaucoma diagnostic criteria between optometrists in Ghana and Nigeria. More Ghanaian than Nigerian optometrists diagnosed glaucoma and over 90% in both countries reported that they frequently performed either tonometry, visual field testing, or fundus examination during glaucoma diagnosis. Ghanaian optometrists were significantly more likely to diagnose glaucoma than Nigerian optometrists (adjusted odd ratio, AOR = 6.15, 95%CI:1.63-23.15, P = .007). Optometrists who have practiced for more than 10 years (AOR = 7.04; 95%CI:1.74-28.47, P = .006) and private practice optometrists (AOR = 3.33; 95%CI:1.13-9.83, P = .03) were more likely to diagnose glaucoma.

CONCLUSIONS

The study provides information for evaluating glaucoma assessment for optometrists in both countries. Optometrists in both countries are reasonably well-equipped to diagnose glaucoma and are practicing at an adequate level, but with room for improvement.

Optometrists' attitudes toward using OCT angiography lag behind other retinal imaging types

PURPOSE

While optometrists' attitudes toward established retinal imaging types are generally positive, they are unknown for optical coherence tomography angiography (OCTA). We performed a cross-sectional survey to estimate attitudes toward OCTA and identify clinician and/or practice characteristics that influence them.

METHODS

A paper-based survey was mailed to 252 randomly selected optometrists in Australia. Five-point Likert-scale items from a previous survey assessing attitudes toward new technology were included to probe respondent characteristics and attitudes toward retinal imaging. Performance expectancy attitudes toward OCTA were elicited by the statement 'I believe OCTA is useful in daily practice'. Mean scores out of five (mean [SD]) were rounded and mapped to appropriate descriptive statements.

RESULTS

The response rate was 47% (118/252). The mean (SD) age of respondents was 44.0 (13.8) years and 50.8% (60/118) were female. Optometrists had 19.9 (14.0) years of clinical experience and 66.9% (79/118) worked at independent practices. In total, 8.5% (10/118) of respondents used OCTA to provide clinical care. Optometrists agreed that optical coherence tomography (OCT), colour fundus imaging, ultra-wide field imaging and fundus autofluorescence (mean scores 3.6-4.7 out of 5) were useful in daily practice but felt neutral about whether OCTA was useful (3.4 [0.8]). Optometrists believed that OCTA was less enjoyable to use (p < 0.0001), less endorsed by peers (p < 0.0001) and felt less confident that they had the knowledge to interpret OCTA (p < 0.0001) compared to other retinal imaging types.

CONCLUSIONS

Optometrists are undecided on whether OCTA is useful in daily practice and had lower expectations that using OCTA would confer job performance benefits compared to other retinal imaging types. Further work is needed to advocate the benefits of using OCTA across the profession.

An analysis of glaucoma repeat measures assessment results: Are core competencies enough?

PURPOSE

The need to validate core competency skills in qualified optometrists wishing to take part in extended roles in glaucoma care has been questioned. This analysis examines the ability of qualified optometrists to perform relevant core competency skills under standardised objective assessment conditions to explore whether such validation is justified. It also investigates if there are associations between performance, gender and length of time since qualification.

METHODS

Anonymised data from the Cardiff University assessment programme for the Wales Optometry Postgraduate Education Centre (WOPEC) Local Optical Committee Support Unit glaucoma referral filtering and monitoring pathway delivered between January 2017 and March 2020 were analysed. Results were combined with demographic data from the General Optical Council register of optometrists in the UK to investigate associations between performance and practitioner characteristics, namely length of time since qualification and gender.

RESULTS

The assessment results of 2215 optometrists practising in England (approximately 15% of all UK registered optometrists and 30% of all optometrists registered in England) were analysed. Failure rates for first time assessment in each of five objective structured clinical examination style practical assessments were 8.5% (van Herick); 8.8% (slit lamp binocular indirect ophthalmoscopy); 10.1% (Goldmann applanation tonometry calibration); 21.9% (Goldmann applanation tonometry) and 23.3% (case scenario interpretation and management). There were either no associations or at most very weak associations between performance and practitioner characteristics.

CONCLUSIONS

Our results suggest that these competencies are not universally present in optometrists practising in England and that ongoing training and assessment of these competencies is justified for entry into extended roles. There are no meaningful associations between performance in these assessments and gender or time since qualification.

The current use of glaucoma virtual clinics in Europe

Objectives

To assess and describe current utilisation, characteristics and perspectives on virtual glaucoma clinics (VGCs) amongst European glaucoma specialists.

Methods

Cross-sectional, anonymized, online questionnaire distributed to all European Glaucoma Society-registered specialists. Questions were stratified into five domains: Demographics, Questions about VGC use, Questions for non-VGC users, COVID-19 effects, and VGC advantages/disadvantages.

Results

30% of 169 participants currently use VGCs, with 53% based in the United Kingdom. Of those using VGCs, 85% reported higher patient acceptance compared to traditional care. The commonest virtual model was asynchronous remote monitoring (54%). Nurses (49%) and ophthalmic technicians (46%) were mostly responsible for data collection, with two-thirds using a mixture of professionals. Consultant ophthalmologists were the main decision-makers in 51% of VGCs. Preferred cohorts were: ocular hypertension (85%), glaucoma suspects (80%), early/moderate glaucoma in worse eye (68%), stable glaucoma irrespective of treatment (59%) and stable glaucoma on monotherapy (51%). Commonest investigations were: IOP (90%), BCVA (88%), visual field testing (85%) and OCT (78%), with 33 different combinations. Reasons for face-to-face referral included: visual field progression (80%), ‘above-target’ IOP (63%), and OCT progression (51%). Reasons for not using VGCs included: lack of experience (47%), adequate systems in place (42%), no appropriate staff (34%) and insufficient time/money (34%). 55% of non-VGC users are interested in their use with 38% currently considering future implementation. 83% stated VGC consultations have increased during the COVID-19 pandemic; 86% of all participants felt that the pandemic has highlighted the importance of VGCs.

Conclusions

A significant proportion of European glaucoma units are currently using VGCs, while others are considering implementation. Financial reimbursement and consensus guidelines are potentially crucial steps in VGC uptake.

An overview of optometrists' diabetic retinopathy practice patterns - a cross-sectional survey

PURPOSE

Contemporary eye care increasingly recommends the use of advanced retinal imaging technology. Anecdotal evidence suggests that this equipment is widely available in primary eye care settings; however, knowledge regarding how optometrists use this equipment in the context of diabetic retinopathy (DR) is limited. This study aimed to obtain a current overview of optometrists' clinical practice behaviours in the detection, screening, diagnosis and management of patients with diabetes.

METHODS

A cross-sectional survey was designed to evaluate optometrists' self-reported clinical practice patterns and perceptions, as well as the availability and impact of retinal imaging equipment specific to DR and diabetic macular oedema (DMO) on optometrists' clinical practice. The survey invited participation from all optometrists practising in Australia.

RESULTS

One hundred and sixty-seven optometrists participated. Optometrists' self-reported confidence in assessing DR and DMO was high. Optometrists' referral patterns considered the severity of DR and DMO before initiating referral to secondary ophthalmology care. Nearly all optometrists (98.8%) indicated that they had some form of retinal imaging equipment available to them in clinical practice. An optical coherence tomography (OCT) device was available to 75.5% of optometrists. A significant association between having an OCT device in the practice and higher self-reported confidence levels in the assessment of DMO was found.

CONCLUSIONS

Many optometrists are well equipped with sophisticated retinal imaging technology for the provision of high-quality eye care. Enhancing optometric training and education programmes can maximise the community benefit of access to this equipment and improve delivery of eye care in the community.

Impact of optical coherence tomography on diagnostic decision-making by UK community optometrists: a clinical vignette study

Purpose

In recent years, there has been widespread investment in imaging technologies by community optometrists in the UK, most notably optical coherence tomography (OCT). The aim of the current study was to determine the value of OCT in the diagnosis of posterior segment diseases in a representative sample of community optometrists using a clinical vignette methodology.

Methods

A group of community optometrists (n = 50) initially completed a standardised training package on OCT interpretation followed by a computer‐based assessment featuring 52 clinical vignettes, containing images of healthy (n = 8) or glaucomatous (n = 18) discs or healthy (n = 8) or diseased (n = 18) fundi. Each vignette featured either a single fundus/disc photographic image, or a combination of a fundus/disc image with the corresponding OCT scan. An expert panel confirmed that the fundus images presented alone and those in combination with OCT data were of a similar level of difficulty and that the cases were typical of those seen in primary care. For each case, the optometrist selected their diagnosis from a pull‐down list and reported their confidence in their decision using a 10‐point Likert scale. Pairwise comparisons of the fundus image alone and fundus image/OCT combination were made for both diagnostic performance and confidence.

Results

The mean percentage of correct diagnoses using fundus imaging alone was 62% (95% CI 59–64%) and for the combination of fundus image/OCT was 80% (95% CI 77–82%). The mean false negative rate with fundus alone was 27% reducing to 13% with the OCT combination. Median confidence scores for fundus imaging alone was 8.0 (IQR 7.0–8.0) and 8.3 (IQR 8.0–9.0) for the combination. Improvements in performance and confidence were statistically significant (p < 0.001).

Conclusion

The results from this vignette study suggests that OCT improves optometrists’ diagnostic performance compared to fundus observation alone. These initial results suggest that OCT provides valuable additional data that could augment case‐finding for glaucoma and retinal disease; however, further research is needed to assess its diagnostic performance in a routine clinical practice setting.

Ocular biometric parameters are associated with non-contact tonometry measured intraocular pressure in non-pathologic myopic patients

PURPOSES

This research aimed to investigate effects and risk factors on non-contact tonometer (NCT) readings in healthy myopic subjects by employing cross-sectional study design.

METHODS

Totally, sixty otherwise healthy myopic volunteers (mean 28.4 years old) with 90% female were recruited in ophthalmic clinic. The routine ophthalmic tests, refractive evaluation, examination central corneal thickness (CCT), depth of anterior chamber, axial length, corneal curvature, white-to-white and NCT were assessed at baseline. The linear-mixed model was utilized to evaluate correlation between the readings and ocular biometric parameters.

RESULTS

For population in this study, mean spherical equivalents were - 4.85 ± 1.79 diopters in right eyes and - 4.63 ± 1.95 diopters in left eyes. Meanwhile, 28.3% of the eyes had a refractive error exceeding - 6.0 diopters. The mean NCT reading was 15.02 ± 3.02 mmHg in left eyes and 15.33 ± 2.96 mmHg in right eyes. Among the factors analyzed, CCT was the most significant parameter associated with NCT readings. After adjusting for the other factors, per one standard deviation increase of central corneal thickness (36.11 μm) was associated a 1.14 (95% confidence interval 0.53-1.77) mmHg elevated NCT reading. The average central corneal curvature, age and spherical equivalence were also significantly and independently associated with NCT readings.

CONCLUSIONS

Central corneal thickness, age, corneal curvature and degree of myopia were independently associated with NCT measured intraocular pressure. Central corneal thickness is one of the most influential factors.

Expanding the traditional role of optometry: Current practice patterns and attitudes to enhanced glaucoma services in Ireland

PURPOSE

To investigate current diagnostic equipment availability and usage for glaucoma case-finding within community optometric practice, and to explore optometrists' attitudes towards an enhanced scope of clinical practice.

METHODS

An anonymous survey was developed, validated, and distributed to all optometrists in Ireland.

RESULTS

199 optometrists (27% of registrants) responded to the survey. 87% had access to the traditional triad of tests necessary to conduct adequate glaucoma case finding. Standard automated perimetry was the most commonly absent (13%) of the three essential screening tests. 64% of respondents indicated that monocular direct ophthalmoscopy was their first choice technique for fundus examination. 47% of respondents had access to contact applanation tonometry, though just 14% used it as first choice during routine eye examinations. Among the 73 participants with access to both contact and non-contact tonometry (NCT), 80.8%, used NCT preferentially. The significant majority (98%) indicated an interest in enhanced glaucoma services with 57% agreeing that postgraduate training was an essential prerequisite to any increase in scope of practice.

CONCLUSION

Irish optometrists are well equipped with the traditional tests used in glaucoma detection. However, implementation of enhanced referral schemes or glaucoma monitoring or management services would require equipment upgrades and associated training in at least half of the surveyed practices. There is strong interest in furthering optometric professional development and expanding the traditional role boundaries of optometrists, incorporating further education as an essential prerequisite to an enhanced scope of practice.

The relationship between unwarranted variation in optometric referrals and time since qualification

PURPOSE

To investigate variation in optometric referral decision-making and the influence of experience and continuing education and training (CET).

METHODS

To gain insight into unwarranted variation in referral activity in the United Kingdom (UK): (1) triage data were audited to investigate source of referral, provisional diagnosis, and outcome; (2) an online system was developed to present two sets of 10 vignettes, designed to avoid prompting answers. Participating optometrists completed 10 pre-CET vignettes, recording their tests and management decisions. The main group of participants chose whatever CET they wished over a 6-month period and then completed another 10 post-CET vignettes. A second group of newly-qualified optometrists completed the vignettes before and after a CET course intervention, followed by a third group of pre-registered optometrists with an intervention of 6-months experience of their pre-registration year.

RESULTS

The audit identified 1951 optometric referrals and 158 optometrists (211 referrals were from general medical practitioners), with 122 of the 158 optometrists making fewer than ten referrals. Two newly-qualified optometrists generated 12.5% of the total referrals in the audit (N = 2162). Many suspect glaucoma referrals were based on a single suspect measurement resulting in a high discharge rate after community review, as did referrals for certain fundus-related appearances for which no treatment was indicated. The intervention of gaining CET points appeared to have no significant impact (p = 0.37) on referral decision-making, although this part of the study was underpowered. Self-selection bias was confirmed in the main group. When the main group and newly-qualified practitioners were compared, the number of referrals was negatively associated with time since qualification (p = 0.005). When all 20 referral decisions were compared, all optometrists referring more than 10 vignette patients came from a group of newly-qualified practitioners up to 2 years post-qualification. Pre-registered optometrists generally referred more appropriately than newly-qualified. Upon qualification, there was a significant increase in the number of sight tests undertaken per day (p = <0.0005).

CONCLUSIONS

Gaining CET points alone is unlikely to significantly improve referral decision-making. Mentoring and targeted CET for the newly-qualified up to 2 years post-qualification should be considered. Ophthalmology replies to the referring newly-qualified optometrist are vital for moderating future referrals and developing clinical confidence.

Comparison of central corneal thickness measurements obtained by community optometrists to those obtained in secondary care

PURPOSE

Corneal central thickness (CCT) is an important risk factor for glaucoma, which also influences intraocular pressure (IOP) measurements. Recently, all community optometrists in Scotland were provided with pachymeters. This study examined the accuracy of CCT measured by community optometrists compared to measurements in the glaucoma clinic.

METHODS

A retrospective analysis of consecutive patients referred to the glaucoma clinic at a university hospital between June and November 2016. 142 of 715 (19.9%) patients had CCT measurements included in the referral, all of whom had repeat measurements in the glaucoma clinic. CCT was measured using the PachPen (Accutome Inc) which generates a CCT reading by automatically taking the average of up to 9 measurements. Measurements were compared using Bland-Altman analysis.

RESULTS

CCT measured by community optometrists was slightly thicker than CCT in the glaucoma clinic (558.3 ± 41.5 vs. 552.6 ± 58.8 µm, P < 0.001), however the mean difference was only 13.8 ± 18.0 µm. In 223 of 284 eyes (78.5%), CCT measurements taken by community optometrists were within 20 µm of those obtained in the glaucoma clinic. 61 of 284 (21.5%) differed by >20 µm, 40 (14.1%) by >30 µm and 17 (6.0%) by >50 µm. There was no significant relationship between difference in CCT and IOP (-0.02, 95% CI -0.05 to 0.002, P = 0.077), gender (0.00, 95%CI -0.01 to 0.01, P = 0.805), or age (-0.01, 95% CI -0.08 to 0.06, P = 0.791).

CONCLUSIONS

There was good overall agreement between CCT measured by community optometrists and measurements obtained in the glaucoma clinic. The tendency for thicker CCT measurements by community optometrists may be due to more peripheral or non-perpendicular positioning of the pachymeter relative to the cornea.

Developing standards for the development of glaucoma virtual clinics using a modified Delphi approach

Purpose

To obtain consensus opinion for the development of a standards framework for the development and implementation of virtual clinics for glaucoma monitoring in the UK using a modified Delphi methodology.

Methods

A modified Delphi technique was used that involved sampling members of the UK Glaucoma and Eire Society (UKEGS). The first round scored the strength of agreement to a series of standards statements using a 9-point Likert scale. The revised standards were subjected to a second round of scoring and free-text comment. The final standards were discussed and agreed by an expert panel consisting of seven glaucoma subspecialists from across the UK. A version of the standards was submitted to external stakeholders for a 3-month consultation.

Results

There was a 44% response rate of UKEGS members to rounds 1 and 2, consisting largely of consultant ophthalmologists with a specialist interest in glaucoma. The final version of the standards document was validated by stakeholder consultation and contains four sections pertaining to the patient groups, testing methods, staffing requirements and governance structure of NHS secondary care glaucoma virtual clinic models.

Conclusions

Use of a modified Delphi approach has provided consensus agreement for the standards required for the development of virtual clinics to monitor glaucoma in the UK. It is anticipated that this document will be useful as a guide for those implementing this model of service delivery.

Factors influencing accuracy of referral and the likelihood of false positive referral by optometrists in Bradford, United Kingdom

AIMS

Levels of false positive referral to ophthalmology departments can be high. This study aimed to evaluate commonality between false positive referrals in order to find the factors which may influence referral accuracy.

METHODS

In 2007/08, a sample of 431 new Ophthalmology referrals from the catchment area of Bradford Royal Infirmary were retrospectively analysed.

RESULTS

The proportion of false positive referrals generated by optometrists decreases with experience at a rate of 6.2% per year since registration (p<0.0001). Community services which involved further investigation done by the optometrist before directly referring to the hospital were 2.7 times less likely to refer false positively than other referral formats (p=0.007). Male optometrists were about half as likely to generate a false positive referral than females (OR=0.51, p=0.008) and as multiple/corporate practices in the Bradford area employ less experienced and more female staff, independent practices generate about half the number of false positive referrals (OR=0.52, p=0.005).

CONCLUSIONS

Clinician experience has the greatest effect on referral accuracy although there is also a significant effect of gender with women tending to refer more false positives. This may be due to a different approach to patient care and possibly a greater sensitivity to litigation. The improved accuracy of community services (which often refer directly after further investigation) supports further growth of these schemes.

Central Corneal Thickness in Spectral-Domain OCT and Associations with Ocular and Systemic Parameters

Background. Optical coherence tomography (OCT) allows quantitative analysis of the anterior segment of the eye with a noncontact examination. The aim of this study is to analyze associations of central corneal thickness (CCT) as measured by OCT with ocular and systemic cardiovascular parameters. Methods. A cross-sectional study of 734 persons was performed in a working age population. Only healthy eyes were included. A comprehensive ophthalmological examination including refraction, noncontact tonometry, and imaging of the anterior segment by SD-OCT was performed. In parallel, a broad range of systemic cardiovascular parameters were measured. Associations were analyzed using a generalized estimating equations' model. Results. CCT measurements showed a significant association with corneal curvature and intraocular pressure: a thinner CCT was associated with a flatter cornea and with lower intraocular pressure (p < 0.001). Age was positively associated with CCT (p < 0.001); all other cardiovascular parameters were not associated. Conclusion. A thinner cornea is associated with a flatter surface and with lower intraocular pressure readings, while there are no independent associations with refraction and systemic cardiovascular parameters. Our findings highlight the value of SD-OCT CCT measurements as a standard tool in anterior segment analysis.

Test-retest variability of retinal nerve fiber layer thickness and macular ganglion cell-inner plexiform layer thickness measurements using spectral-domain optical coherence tomography

PURPOSE

To evaluate the test-retest variability of spectral-domain optical coherence tomography (OCT) in measurement of retinal nerve fiber layer (RNFL) thickness and macular ganglion cell-inner plexiform layer (GCIPL) thickness.

METHODS

A total of 65 eyes of healthy subjects were enrolled in this observational cross-sectional study. RNFL thickness and GCIPL thickness were measured using the repeat scan optic cube and macular cube protocol using Cirrus HD-OCT (software version 6.0). A single operator obtained 3 measurements during 1 session to determine test-retest variability. Intrasession repeatability was defined by intraclass correlation, limits of agreement, and coefficient of variation.

RESULTS

The mean age of patients was 37.89±15.11 years (range, 10 to 70 y). The mean RNFL thickness readings as measured during 3 sessions were 93.89±9.73, 93.63±10.00, and 93.55±9.64 μm and average GCIPL thickness measurements were 82.90±4.61, 82.98±4.24, and 83.06±4.36 μm, respectively. Coefficient of variation was 1.2 for average RNFL thickness and 0.82 for average GCIPL thickness. The intraclass correlation coefficient showed a good correlation between repeat measurements for both average RNFL and GCC thicknesses (0.994 and 0.990, respectively). The limits of agreement (95% confidence interval) for the 3 sessions ranged from -3.61 to 4.13 μm for the average RNFL thickness and -2.55 to 2.40 μm for GCIPL thickness measurements.

CONCLUSIONS

In healthy eyes, Cirrus HD-OCT shows excellent intrasession repeatability for RNFL and GCIPL thickness measurements.

A survey of current and anticipated use of standard and specialist equipment by UK optometrists

PURPOSE

To investigate current and anticipated use of equipment and information technology (IT) in community optometric practice in the UK, and to elicit optometrists' views on adoption of specialist equipment and IT.

METHODS

An anonymous online questionnaire was developed, covering use of standard and specialist diagnostic equipment, and IT. The survey was distributed to a random sample of 1300 UK College of Optometrists members.

RESULTS

Four hundred and thirty-two responses were received (response rate = 35%). Enhanced (locally commissioned) or additional/separately contracted services were provided by 73% of respondents. Services included glaucoma repeat measures (30% of respondents), glaucoma referral refinement (22%), fast-track referral for wet age-related macular degeneration (48%), and direct cataract referral (40%). Most respondents (88%) reported using non-contact/pneumo tonometry for intra-ocular pressure measurement, with 81% using Goldmann or Perkins tonometry. The most widely used item of specialist equipment was the fundus camera (74% of respondents). Optical Coherence Tomography (OCT) was used by 15% of respondents, up from 2% in 2007. Notably, 43% of those anticipating purchasing specialist equipment in the next 12 months planned to buy an OCT. 'Paperless' records were used by 39% of respondents, and almost 80% of practices used an electronic patient record/practice management system. Variations in responses between parts of the UK reflect differences in the provision of the General Ophthalmic Services contract or community enhanced services. There was general agreement that specialised equipment enhances clinical care, permits increased involvement in enhanced services, promotes the practice and can be used as a defence in clinico-legal cases, but initial costs and ongoing maintenance can be a financial burden. Respondents generally agreed that IT facilitates administrative flow and secure exchange of health information, and promotes a state-of-the-art practice image. However, use of IT may not save examination time; its dynamic nature necessitates frequent updates and technical support; the need for adequate training is an issue; and security of data is also a concern.

CONCLUSION

UK optometrists increasingly employ modern equipment and IT services to enhance patient care and for practice management. While the clinical benefits of specialist equipment and IT are appreciated, questions remain as to whether the investment is cost-effective, and how specialist equipment and IT may be used to best advantage in community optometric practice.

Therapeutic endorsement enhances compliance with national glaucoma guidelines in Australian and New Zealand optometrists

PURPOSE

Previous studies confirmed that optometrists have access to and confidence in applying clinical tests recommended for glaucoma assessment. Less is known about factors best predicting compliance with national clinical guidelines and thus by inference, the provision of suitable care by primary care ophthalmic practitioners. We utilised the unique two-tiered profession (therapeutic and non-therapeutic scope of practice) in Australia and New Zealand to assess the prospective adherence to glaucoma guidelines dependent on the clinician's background.

METHODS

Australian and New Zealand optometrists were surveyed on ophthalmic techniques for glaucoma assessment, criteria for the evaluation of the optic nerve head, glaucoma risk categories and review times while also recording background, training, and experience. Parameters identifying progression/conversion and patients' risk levels were analysed comparatively to ophthalmologists' opinions. Linear regression analysis identified variables significantly improving the likelihood of concordance with guidelines.

RESULTS

Reported application of techniques complied well with glaucoma guidelines although gonioscopy and pachymetry, pupil dilation for optic nerve head examination, and acquisition of permanent records were less frequently employed. The main predictors for entry-level diagnostic standards were therapeutic endorsement together with the associated knowledge of relevant guidance and procedural confidence. Other findings suggested a potential underestimation in the value of optic disc size and intraocular pressure for the prediction of glaucoma risk, while optometrists more frequently relied on the outcomes of non-standardised automated perimetry and auxiliary imaging.

CONCLUSIONS

Optometrists in Australia and New Zealand may not always exercise optimal clinical acumen regarding techniques/criteria for glaucoma diagnosis. Therapeutic endorsement was gradually adopted in different jurisdictions in various forms since 1999 and is mandatory for registration since late 2014. The result of the two-tiered optometric cohorts suggest that inclusion of therapeutic training as part of the core training is likely a key factor to enhanced compliance with glaucoma guidelines. Improved adherence to the current clinical standards should positively impact on the facilitation of appropriate glaucoma diagnosis and management. Obligatory knowledge and possibly accreditation of available guidelines might ensure a uniform standard in glaucoma testing protocols in concordance with compulsory entry-level skills.

Cambridge community Optometry Glaucoma Scheme

BACKGROUND

With a higher life expectancy, there is an increased demand for hospital glaucoma services in the United Kingdom.

DESIGN

The Cambridge community Optometry Glaucoma Scheme (COGS) was initiated in 2010, where new referrals for suspected glaucoma are evaluated by community optometrists with a special interest in glaucoma, with virtual electronic review and validation by a consultant ophthalmologist with special interest in glaucoma.

PARTICIPANTS

1733 patients were evaluated by this scheme between 2010 and 2013.

METHODS

Clinical assessment is performed by the optometrist at a remote site. Goldmann applanation tonometry, pachymetry, monoscopic colour optic disc photographs and automated Humphrey visual field testing are performed. A clinical decision is made as to whether a patient has glaucoma or is a suspect, and referred on or discharged as a false positive referral. The clinical findings, optic disc photographs and visual field test results are transmitted electronically for virtual review by a consultant ophthalmologist.

MAIN OUTCOME MEASURES

The number of false positive referrals from initial referral into the scheme.

RESULTS

Of the patients, 46.6% were discharged at assessment and a further 5.7% were discharged following virtual review. Of the patients initially discharged, 2.8% were recalled following virtual review. Following assessment at the hospital, a further 10.5% were discharged after a single visit.

CONCLUSIONS

The COGS community-based glaucoma screening programme is a safe and effective way of evaluating glaucoma referrals in the community and reducing false-positive referrals for glaucoma into the hospital system.

Agreement of glaucoma specialists and experienced optometrists in gonioscopy and optic disc evaluation

Purpose

To compare the diagnostic performance of glaucoma specialists and experienced optometrists in gonioscopy and optic disc assessment.

Methods

This study was done to validate the diagnostic performance of two experienced optometrists for using their skills of detecting glaucoma using gonioscopy and optic disc assessment in a major epidemiological study, the L V Prasad Eye Institute Glaucoma Epidemiology and Molecular Genetics Study (LVPEI-GLEAMS). Gonioscopic findings for 150 eyes were categorized as 0, 1 and 2 for open angle, primary angle closure suspect (PACS) and primary angle closure (PAC) respectively. Optic disc findings for 200 eyes were categorized as 0, 1 and 2 for normal, suspects and glaucomatous respectively. Weighted kappa (κ) and diagnostic accuracy parameters were calculated. Two optometrists (#1 and #2) participated in the study.

Results

Agreement between glaucoma specialists and optometrist for interpretation of gonioscopy to discriminate PACS and PAC from open angles and for interpretation of optic disc to discriminate glaucomatous and suspicious discs from normal, the kappa (κ) was 0.92 and 0.84 and 0.90 and 0.89 for optometrists #1 and #2 respectively. Sensitivities and specificities were above 90% for gonioscopy. Optic disc evaluation had specificities greater than 95% to discriminate normal from glaucomatous discs while the sensitivities were 83% and 93% for optometrists #1 and #2 respectively.

Conclusion

Agreement between optometrists and glaucoma specialists, in diagnostic performance of gonioscopy and optic assessment was excellent with high sensitivity and specificity. Hence, we conclude that the experienced optometrists can detect glaucoma accurately in the LVPEI-GLEAMS.

Advice about diet and smoking for people with or at risk of age-related macular degeneration: a cross-sectional survey of eye care professionals in the UK

Background

In the absence of a cure, there has been considerable interest in attempts to prevent or reduce the progression of age-related macular degeneration (AMD) by targeting particular modifiable risk factors. The aim of this study was to conduct a cross-sectional survey of the current practice of UK eye care professionals in relation to advice given on diet and other lifestyle modifications for patients with or at risk of AMD.

Methods

Optometrists and ophthalmologists on the membership databases of professional organisations for the two professions were invited to participate in an online survey. The survey was open for 12 weeks between July and September 2012.

Results

A total of 1,468 responses were received (96.3% from optometrists and 3.7% from ophthalmologists). The response rate of those receiving the invitation was 16.2% (1,414/8735) for optometrists and 6% (54/1460) for ophthalmologists. A majority of respondents reported that they frequently provide dietary advice to patients with established AMD (67.9%) and those at risk of AMD (53.6%). Typical advice consisted of a recommendation to eat plenty of leafy green vegetables and eat more oily fish. The decision to recommend nutritional supplements was based on the risk of progression to advanced AMD, with approximately 93% of respondents recommending supplementation in a patient with advanced AMD in one eye. However for the majority, the type of supplement recommended did not comply with current best research evidence, based on the findings of the Age-related Eye Disease Study (AREDS). Only one in three optometrists regularly assessed smoking status and advised on smoking cessation.

Conclusions

Within a large sample of eye care professionals, consisting predominantly of optometrists, who responded to a cross-sectional survey, there was active engagement in providing nutritional advice to patients with or at risk of AMD. However, the results demonstrate a need to raise awareness of the evidence underpinning the use of nutritional supplements together with an increased involvement in targeted smoking cessation.

Comparison of optometrist glaucoma referrals against published guidelines

PURPOSE

To examine if community optometrists follow published guidelines for referral of patients with suspect glaucoma to the hospital eye service.

METHODS

A retrospective audit of new optometrist-initiated referrals to the Glaucoma Service at Moorfields Eye Hospital, London was performed. Clinical data from referral letters recorded included evidence of intraocular pressure (IOP) measurement and tonometer used. Referral letter information was compared to 2009 guidelines published jointly by the College of Optometrists and Royal College of Ophthalmologists on referring glaucoma suspect patients.

RESULTS

A total of 289 new patients were seen in the Glaucoma Service over a 6 week period from 4th January 2011; a 100% hospital record retrieval rate was obtained. Of these, 114 (39%) were optometrists initiated referrals. Optometrist letters were available for 105 patients. IOP measurements were recorded in 102 (97%); most practitioners used non-contact tonometry (NCT; n = 69; 68%). Practitioners recorded <4 NCT readings per eye (4 readings: n = 3, 4%; 3 readings: n = 42, 61%; 2 readings: n = 6, 9%; 1 reading: n = 18, 26%). Seventy-seven patients (73%) reported with raised IOP as the main referral reason; of these, 33 (43%) were referred with raised IOP in isolation. NCT was the instrument used in the majority of these raised IOP cases (n = 56; 73%). In cases where raised IOP in isolation was the referral reason, 24 (73%) were recorded using NCT; 10 (30%) provided repeat IOP measurement data in the letter. One hundred and two (97%) referred patients attended the hospital appointment. Thirty (29%) were deemed not to have glaucoma, with the remainder diagnosed with ocular hypertension (n = 25; 25%), glaucoma suspect/glaucoma (n = 35, 34%) or narrow angles requiring intervention (n = 12, 12%). Thirty of the 33 patients referred with raised IOP in isolation attended their hospital visit. Ten (33%) of these patients were subsequently discharged. Six (20%) patients had IOP within normal limits when measured with applanation tonometry; all of these patients were kept within the service.

CONCLUSIONS

Community optometrists using NCT for measurement should be reminded of the guidelines on number of readings to take and also the value of repeating NCT measures when appropriate. This may help to increase the accuracy of glaucoma suspect referrals to hospital eye service.