Relationship Between Intraocular Pressure and Age: A Population-Based Study in Nepal.

PRCIS: Intraocular pressure (IOP) decreased with age in a population-based study in Nepal, from a mean of 14.1 mm Hg among those 60-64 years old to 13.0 mm Hg among those 80 years old or older. PURPOSE: Few studies have assessed the distribution of IOP from the Indian subcontinent, despite its large population and high burden of glaucoma. The objective of this study was to assess the distribution of IOP measurements from adults living in a lowland region of Nepal. METHODS: In a population-based cross-sectional study, all individuals aged 60 years and older from an area of lowland Nepal were invited for an IOP assessment with a rebound tonometer. RESULTS: Of 160 communities (28,672 people aged ≥60 y) enrolled, 79 (13,808 people aged ≥60 y) were randomly selected for IOP testing. Of those eligible, 10,017 (72.5%) individuals underwent tonometry. Mean IOP decreased monotonically over 5-year age groups, from 14.1 mm Hg (SD: 3.6) among those aged 60-64 years to 13.0 mm Hg (SD: 4.2) among those 80 years or older. The 97.5th percentile IOP measurement was 21.0 mm Hg for all age groups. In adjusted analyses, younger age, self-reported diabetes, and higher population density were each associated with higher IOP, and self-reported cataract surgery was associated with lower IOP. CONCLUSIONS: Mean IOP was lower among older individuals in Nepal, consistent with many studies from East Asia and in contrast to many studies from western populations. These results suggest that ethnic background might be a consideration when diagnosing ocular hypertension.

Should We Perform Early Cataract Surgery? A Patient Reported Outcome Study.

PURPOSE: Current guidance states that access to cataract surgery should not be restricted by visual acuity (VA); nevertheless, 6/12 is used as a cut-off criterion in some health institutions. This study aims to determine the benefits of performing cataract surgery in patients with VA of 6/9 or better in both eyes; determine whether these benefits change over time; and compare the benefit observed between early first eye and second eye surgery. PATIENTS AND METHODS: Fifty adults with VA at least 6/9 in the worst eye and no ocular comorbidity were recruited. The Visual Function Index (VF-14) and Impact of Visual Impairment (IVI) questionnaires were conducted pre-operatively, 4 months post-operatively, and 12 months post-operatively. The t-test or a non-parametric equivalent was used to compare averages between groups. RESULTS: The mean change in VF-14 from baseline to 4 months was 16.43 (95% CI 12.49-20.50, p < 0.001) and the median change in IVI was 6.5 (IQR 9.75, p < 0.001). There was no significant difference between 4-month and 12-month follow-up (p > 0.05). There was no significant difference in the change in visual function between the first and second eye surgery (p > 0.05). CONCLUSION: This study provides evidence that visual function improves after cataract surgery in patients with pre-operative VA of 6/9 or better. The improvement observed was clinically significant and unchanged a year after surgery. Visual function improved after second eye as much as after first eye surgery. Assessing patient reported visual function may give a more realistic indication of the benefit of early cataract surgery than relying on VA alone.

Agreement amongst consultant ophthalmologists on levels of visual disability required for eligibility for certificate of sight impairment : Sight impairment registration using binocular composite visual fields.

BACKGROUND: Registration as sight impaired allows access to services important for patients. The rates of sight impairment due to visual field loss are underestimated. Previous work has shown that evaluation of visual field defects in both eyes produces poor agreement among ophthalmologists for categorisation of patients as eligible for sight impairment registration. AIM: To evaluate the impact of binocular summation of both eye glaucomatous visual field defects on agreement for sight impairment registration. METHODS: Thirty consultant ophthalmologists (Graders), graded 50 glaucomatous visual field sets. Each consisted of both monocular fields and summated binocular plots. Graders classified the visual field sets as sight impaired (SI), severely sight impaired (SSI) or neither. Trichotomous, (SI, SSI or no sight impairment) and dichotomous (any sight impairment versus no sight impairment) concordance values were estimated for the group of graders as a whole and for glaucoma and non-glaucoma experts. RESULTS: For trichotomous analysis the overall kappa agreement rate was 0.29; for dichotomous analysis it was 0.40. There was no material difference between glaucoma experts and non-experts. CONCLUSION: Overall agreement was modest. Grading for SI showed the poorest levels of agreement. Using binocular fields does not appear to improve concordance for sight impairment registration. Moreover, there is no difference in agreement between glaucoma and non-glaucoma experts. An overall score for visual disability using mean deviation may be a more pragmatic approach.

Prevalence of treatment with glaucoma medication in Scotland, 2010-2017.

AIMS: To report the number and demographic distribution of patients receiving intraocular pressure (IOP)-lowering medications across the whole population of Scotland for the years 2010-2017 and, using national census data, show how the observed changes compare with those predicted by the increasing age of the population structure over this period. METHODS: Data were sourced from the Prescribing Information System of the NHS Information and Statistics Division for Scotland. The number of patients dispensed any IOP-lowering medication from a community pharmacy during each calendar year was collected by gender and by 5-year age bands. National census data were used to model the expected annual increase in treatment numbers due to population ageing. RESULTS: The number of treated patients in 2017 was 61 249 which represents 1.13% of the whole population (or 2.16% over 40 years of age). The number increased from 48 178 in 2010-an increase over this period of 27.13% (3.88% per year).Prevalence increased with age, reaching 10.67% in those over 90 years. After age adjustment, more men were treated than women (OR 1.26).The expected number treated in 2017 based on census predictions was 54 075 (an increase of 5897 (12.24%) from 2010). The observed growth of 27.13% was 2.22-fold greater than the rate expected by population changes over the period 2010-2017. CONCLUSION: The number of patients on medication for glaucoma and ocular hypertension in Scotland is increasing. The rate of increase cannot be explained by changes in the size and age structure of the population alone.

Establishing an allied health professional delivered selective laser trabeculoplasty service in Scotland.

PURPOSE: To describe the process of establishing a selective laser trabeculoplasty (SLT) service delivered by experienced allied health professionals (AHP) in a Scottish NHS Hospital Eye Service, and assess the safety and efficacy in comparison with SLT performed by ophthalmologists. METHODS: A training scheme for AHPs who were experienced in extended roles within the glaucoma service was developed, consisting of supervised training by a consultant ophthalmologist specialising in glaucoma leading to the AHPs independently delivering SLT. A prospective audit of consecutive SLT procedures performed by AHPs between November 2015 and April 2017 was performed. Data were analysed and compared to a previous intradepartmental audit of SLT performed by ophthalmologists (consultants and trainees). RESULTS: A total of 325 eyes of 208 patients underwent SLT, of which 117 patients had bilateral SLT in a single session. The overall rate of complications was 3.9%, however these were minor and/or self-limiting (this compared to a 3.8% complication rate in the ophthalmologist delivered SLT series). The rate of intraocular pressure (IOP) spike was 0.3%, compared to 1.4% in the ophthalmologist delivered SLT series. Mean IOP at listing was 20.9 ± 5.1 mmHg, 17.3 ± 4.5 mmHg at 3 months post SLT and 17.6 ± 3.7 mmHg at 12 months-a median reduction of 16.7% at 3 months and 17.4% at 12 months. There was no statistically significant difference between the percentage reduction in IOP in the AHP and ophthalmologist delivered SLT groups at 3 or 12 months. CONCLUSIONS: This is the first service of its kind in Scotland and the outcomes of this study demonstrate that the AHP delivered SLT service is at least as safe as the previous ophthalmologist delivered SLT service. The data demonstrate a similar efficacy between AHP and ophthalmologist delivered SLT. In the face of increasing demand and workload, this is a practical model in service commissioning to free up medical clinicians for more complex glaucoma management.

Cataract surgery refractive outcomes: representative standards in a National Health Service setting.

BACKGROUND/AIMS: To report refractive outcomes from an National Health Service (NHS) cataract surgery service and assess if results meet suggested benchmark standard. METHODS: Details of all patients undergoing cataract surgery in the Southern General and New Victoria hospitals in Glasgow, UK, between November 2006 and December 2016 were prospectively entered into an electronic database. Patients were reviewed 4 weeks postoperatively in the eye clinic and underwent refraction at their local optometrist prior to this appointment. Surgically uncomplicated cases with in the bag' non-toric intraocular lens implantation were included. Patients with previous laser refractive procedures or failing to achieve 6/12 acuity or better postoperatively were excluded. Proximity to targeted postoperative refraction was documented. RESULTS: Over this 10-year period, 11 083 eyes underwent cataract surgery. Of these, 8943 eyes of 6936 patients (80.69%) met the inclusion criteria and had both target and postoperative outcome refraction recorded. The mean difference between the targeted and outcome refraction was -0.07 D (SD 0.67). The mean absolute error was 0.50 D. Postoperative refraction was within 1 D of target refraction for 7938 eyes (88.76%) and within 0.50 D for 5577 eyes (62.36%). CONCLUSION: Refractive outcomes following routine cataract surgery reported here are well within the targets recommended by the Royal College of Ophthalmologists and European guidelines, but suggest that higher cataract refractive outcome benchmark standards may not yet be a realistic expectation for all NHS units with current biometry practice.

The impact of SIGN glaucoma guidelines on false-positive referrals from community optometrists in Central Scotland.

BACKGROUND: Since the introduction of National Institute for Health and Care Excellence glaucoma guidelines 2009, the number of referrals from community optometrists to hospital eye services has increased across the UK, resulting in increase in first visit discharge rates (FVDRs). AIM: To assess the impact of Scottish Intercollegiate Guidelines Network (SIGN) 144 on quality of referrals from community optometrists. METHODOLOGY: A retrospective study of patient records who attended as new adult glaucoma referrals to clinics in Princess Alexandra Eye Pavilion, Edinburgh, and in Greater Glasgow and Clyde, was carried out across October-November 2014 (group 1) and September-October 2016 (group 2), before and after the introduction of SIGN 144. The primary outcome of this study is FVDRs. A secondary outcome is the extent of compliance to referral recommendations by SIGN guidelines. RESULTS: Three hundred and twelve and 325 patients were included in groups 1 and 2, respectively. There was a significant decline in FVDRs between these two periods from 29.2% to 19.2%. (p=0.004) (OR 0.58 (95%CI 0.40 to 0.84)). Post-SIGN guidelines, 87% of referrals were compliant to SIGN referral criteria while 13% remained non-compliant. The main reasons for non-compliance were no repeatable visual field defects (42.0%) and referrals due to high intraocular pressure were either not repeated or not interpreted in the context of age and central corneal thickness (36.8%). CONCLUSION: Patients referred after the introduction of SIGN guidelines were 33.5% less likely to be discharged at the first visit. Although compliance to most recommendations in SIGN guidelines has improved, there is still a need to improve adherence to referral criteria.

Outcome of repeat trabeculectomies: long-term follow-up.

AIM: To assess medium-term to long-term outcomes of a cohort of repeat trabeculectomy augmented with mitomycin C (MMC). METHODS: A prospective evaluation of consecutive separate site repeat MMC-augmented trabeculectomies undertaken at a single institution between October 2000 and December 2012. Information regarding visual acuity (VA), intraocular pressure (IOP), visual field progression, postoperative interventions, surgery complications and success of surgery are presented.Complete and qualified (ie, with or without glaucoma medication) success rates were presented on the basis of three levels of IOP control: ≤21, ≤17 and ≤14 mm Hg without hypotony or reoperation. RESULTS: Fifty-six eyes of 56 patients were evaluated. Thirty-seven per cent of the cohort had a previously augmented trabeculectomy. Mean follow-up was 6.3±3.4 years. At 60-month follow-up, 56.1% of patients achieved complete success and 75.6% achieved qualified success at the ≤21 mm Hg target. Complete and qualified success rates were 53.7% and 73.2%, respectively at the ≤17 mm Hg target and 51.2% and 61.0%, respectively at the ≤14 mm Hg target. Mean preoperative IOP was 29.1±6.0 mm Hg. At the 60-month follow-up visit the mean IOP was 12.6±4.7 mm Hg. Requirement for topical medications dropped from a mean of 2.9 to 0.5 per patient. No medications were required in 68.3%. CONCLUSIONS: Safe repeat trabeculectomy technique with antimetabolite titrated against the individual patients risk profile can result in improved results in the medium-term to long-term.

Conjunctival Chemosis as a Specific Feature of Pseudomonas aeruginosa Corneal Ulcers.

PURPOSE: Timely identification of a bacterial agent and its corresponding antibiotic sensitivity pattern is paramount in the management of infective corneal ulcers. Isolating the microbiological agents can take time; during this time, the initial therapy used is a chosen form of broad-spectrum antibiotics. There are no specific features of bacterial corneal ulcers that aid in identification of the involved pathogen with certainty. A clinical "marker" would undoubtedly be useful in the management of corneal ulcers. METHODS: Early clinical photographs and clinical notes of 62 cases with confirmed infective corneal ulcers were examined by a masked reviewer. RESULTS: Conjunctival chemosis was observed in 14 out of 16 cases of Pseudomonas aeruginosa-related corneal ulcers, as compared with 6 out of 46 cases caused by other organisms. The association between conjunctival chemosis and Pseudomonas aeruginosa is statistically significant, with P value <0.000001 and odds ratio 42.0 (7.2-470) using the Fisher exact test. CONCLUSIONS: Our findings suggest that conjunctival chemosis could be a useful marker to predict the presence of Pseudomonas aeruginosa in bacterial corneal ulcers.

Validity of the Monocular Trial of Intraocular Pressure-Lowering at Different Time Points in Patients Starting Topical Glaucoma Medication.

IMPORTANCE: Establishing the true therapeutic effect of eyedrops when initiating glaucoma therapy is important. Accurate prediction of the intraocular pressure (IOP)-lowering response in the fellow eye when using a monocular trial eliminates the need for additional office visits to confirm the therapeutic effect. OBJECTIVE: To investigate the validity of the monocular trial in patients commencing topical glaucoma treatment at different time points. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study of untreated patients with open-angle glaucoma or ocular hypertension at a hospital-based glaucoma service among treatment-naive individuals. The study dates were October 1, 2008, to November 30, 2009. INTERVENTIONS: Participants had 8 visits. After the recruitment visit, IOP was measured in both eyes by masked applanation tonometry at 8 am, 11 am, and 4 pm for 7 consecutive weeks. Treatment with travoprost, 0.004%, was commenced at week 3 in the trial eye and at week 4 in the fellow eye. MAIN OUTCOMES AND MEASURES: Three IOP outcomes were measured for the trial eye, including unadjusted IOP-lowering effect, adjusted IOP-lowering effect, and true therapeutic effect. RESULTS: Of 30 topical glaucoma treatment-naive individuals (11 male and 19 female), 16 had ocular hypertension and 14 had primary open-angle glaucoma. Their mean (SD) age was 64.4 (12.6) years (age range, 42-88 years). The unadjusted IOP-lowering effect overestimated the true therapeutic effect by mean (SD) 2.5 (4.8), 3.1 (3.8), and 4.9 (4.4) mm Hg at 8 am, 11 am, and 4 pm, respectively, and the mean (SD) adjusted IOP-lowering effect was almost identical to the true therapeutic effect at each of the 3 time points (0.43 [3.87], 0.02 [2.82], and -0.40 [3.90]), respectively. The correlation between the unadjusted effect of treatment and the true therapeutic effect was 0.55 (95% CI, 0.23-0.76), and the effect when adjusted by the monocular trial was 0.72 (95% CI, 0.49-0.86). Fellow eye responses to treatment were correlated at all time points (r range, 0.78-0.86). Treatment did not demonstrate any effect on the diurnal pattern of IOP. CONCLUSIONS AND RELEVANCE: The monocular trial of therapy is effective in accurately predicting the response of an untreated eye to monotherapy with a prostaglandin analogue at all daytime time points measured. There is no requirement for patients to be seen at the same time of day after treatment has commenced. The effect in the first eye predicts both the likelihood and magnitude of an effect in the second eye at all time points during office hours and negates the requirement for an additional visit to check the therapeutic effect when commencing therapy in the second eye.

Glaucoma-service provision in Scotland: introduction and need for Scottish Intercollegiate Guidelines Network guidelines.

PURPOSE: To describe the pattern of glaucoma-service delivery in Scotland and identify areas for improvement, taking into account Scottish General Ophthalmic Services (GOS) arrangements and the Eye Care Integration project, and to design Scottish Intercollegiate Guidelines Network (SIGN) guidelines to refine the primary and secondary interface of glaucoma care. MATERIALS AND METHODS: A glaucoma-survey questionnaire was sent to all consultant glaucomatologists in Scotland. The design of SIGN guidelines was based on the results of the questionnaire using SIGN methodology. RESULTS: Over 90% of Scottish glaucoma care is triaged and delivered within hospital services. Despite GOS referral, information is variable. There are no consistent discharge practices to the community. These results led to defined research questions that were answered, thus formulating the content of the SIGN guidelines. The guideline covers the assessment of patients in primary care, referral criteria to hospital, discharge criteria from hospital to community, and monitoring of patients at risk of glaucoma. CONCLUSION: With increasing age and limitations to hospital resources, refining glaucoma pathways between primary and secondary care has become a necessity. Scotland has unique eye care arrangements with both the GOS and Eye Care Integration project. It is hoped that implementation of SIGN guidelines will identify glaucoma at the earliest opportunity and reduce the rate of false-positive referrals to hospital.

Repeatability of measurements of effectiveness of glaucoma medication.

AIMS: To determine short-term repeatability of the effect of intraocular pressure (IOP) reducing medication and the number of repeated measurements necessary to estimate therapeutic effect with a given degree of precision. METHODS: IOP was measured at 8:00, 11:00 and 16:00 h at each of three weekly visits in untreated patients with primary open-angle glaucoma or ocular hypertension. After starting travaprost (0.004%) to both eyes, the measurements were repeated for a further three weekly visits. Repeatability of the change in IOP 1, 2 and 3 weeks after starting treatment was reported as the coefficient of repeatability (CR) and coefficient of variability (CV). RESULTS: Mean reduction in IOP was 7.5 mm Hg (29.9%). CR and CV between visits were 7.8 mm Hg and 37.2%, respectively. Repeated estimates of the effectiveness of treatment in the same subject at the same time of day would, therefore, be expected to lie within a range of 7.8 mm Hg and within ±73.2% of the mean effect with 95% confidence. A reduction in IOP less than 7.8 mm Hg over a single pair of measurements would be indistinguishable from measurement error. Precision improves from ±73.2% for a single pair of readings to ±25.9% for eight pairs. CONCLUSIONS: Day-to-day repeatability in the estimation of medication effectiveness is poor even for time-of-day standardised measurements and the number of IOP measurements required to achieve precision adequate for use in clinical practice is large.

Day-to-day variability in intraocular pressure in glaucoma and ocular hypertension.

AIMS: To investigate the day-to-day repeatability of intraocular pressure (IOP) measurements. METHODS: A prospective cohort study of untreated patients presenting with primary open-angle glaucoma or ocular hypertension presenting with IOP>21 mm Hg. IOP was measured by masked Goldmann tonometry at 08:00, 11:00 and 16:00 at each of the three weekly visits. After starting travaprost (0.004%) to both eyes, the measurements were repeated for a further three weekly visits. Day-to-day repeatability was estimated before and after commencing medication and reported as the coefficient of repeatability and coefficient of variability. RESULTS: At the 8:00 time point, mean IOPs were 26.1 and 17.9 mm Hg in the eye with higher pressure before and after starting treatment, respectively. Coefficient of repeatability and coefficient of variability were 6.8 mm Hg and 10.0%, respectively, before treatment, and 4.6 mm Hg and 10.5% on treatment. Therefore, before treatment and after starting medication the IOP lay within a range of ±20% of the mean IOP with 95% confidence. CONCLUSIONS: The non-therapeutic variability from day to day significantly undermines the precision of IOP estimation and of the estimation of medication effectiveness even when the time of day is standardised in patients with primary open-angle glaucoma/ocular hypertension.