Despite a universal health care system, access to vision care in Canada is not necessarily equally accessible to all patients. The purpose of this review was to explore the association between socioeconomic status (SES) and vision care utilization in Canada. Medline, Embase, CINAHL, and Cochrane were searched from inception to January 2024 for relevant articles containing original data. Studies that explored the association between SES and vision care utilization in Canadian patients were included. Risk of bias was assessed using the Newcastle-Ottawa and AXIS assessment tools. Descriptive statistics were used to summarize findings. The review was registered in PROSPERO (registration number: CRD42024502482) and followed PRISMA guidelines. The search yielded 2,670 records with 23 studies included in this review. The included studies covered all provinces and ranged in date between 1985 and 2022. The included studies explored the relationship between SES and utilization of ophthalmic care, optometric care, or both. Overall, 17 of the 23 studies found that patients of lower SES were significantly more likely to have decreased usage of vision care. Decreased vision care utilization was found for all optometry, ophthalmology care, and diabetic retinopathy screening, as well as for patients of all ages, and in all provinces. Low socioeconomic status was consistently associated with decreased vision care utilization for patients of all ages. Efforts are required to increase accessibility to vision care for low-income individuals and to improve health equity.
Background/aims To report a first-in-human trial in open-angle glaucoma (OAG) subjects treated with a new microinterventional biostent-reinforced cyclodialysis technique to enhance supraciliary aqueous drainage. Methods Subjects (N=10; 74.1±7.9 years old) with OAG and cataracts underwent combined phacoemulsification cataract surgery with implantation of a permanent endoscleral supraciliary biostent to reinforce a controlled cyclodialysis cleft. The biostent comprised decellularised scleral allograft tissue microtrephined into a polymer tubular implant intraoperative/postoperative safety, intraocular pressure (IOP) and glaucoma medications were tracked through 12 months postimplantation. Results Baseline medicated IOP averaged 24.2±6.9 mm Hg with subjects using 1.3±0.8 IOP-lowering medications. Successful biostent implantation was achieved in all individuals without significant complications. Immediate IOP lowering was sustained through 1 year. Twelve-month mean IOP was reduced 40% from baseline to 14.6±3.2 mm Hg (p=0.004; paired two-tailed t-test), and 80% of patients achieved >20% IOP reduction. Biostenting reduced glaucoma medication use 62%, from a baseline mean of 1.3 required medications to 0.5 medications (p=0.037) at postoperative 12 months. The biotissue implant was well tolerated and demonstrated good endothelial safety with only 11% endothelial cell loss at 12 months after combined phaco-biostenting surgery, similar to that expected after phacoemulsification alone. Mean BCVA increased from baseline 20/130 Snellen to 20/36 at postoperative 12 months (p=0.001). Conclusion Supraciliary biostenting in OAG patients is well tolerated, has a good safety profile and produces long-term IOP-lowering while reducing glaucoma medication requirements.
PURPOSE: To evaluate differences in higher order aberrations (HOAs) between femtosecond laser–assisted cataract surgery (FLACS) and manual cataract surgery. METHODS: In this retrospective cohort study, consecutive patients undergoing FLACS or manual cataract surgery with implantation of an intraocular lens from January 2017 to February 2018 were recruited. Patients underwent aberrometry testing at least 2 months postoperatively. The primary endpoint was internal coma < 0.32 µm, and secondary outcomes included patient-reported vision quality. Generalized estimating equations accounting for within-patient correlation were used for analysis. RESULTS: A total of 57 eyes underwent FLACS (mesopic pupil size: 4.74 ± 1.37 mm) and 50 eyes underwent manual cataract surgery (pupil size: 4.99 ± 1.24 mm). The proportion of eyes reaching internal coma < 0.32 µm was significantly greater following FLACS (54 of 57 eyes, 94.7%) relative to manual cataract surgery (39 of 50 eyes, 78.0%) (odds ratio [OR] = 5.08, 95% confidence interval [CI] = 1.24 to 20.85, P = .024). The median internal coma was 0.10 µm for FLACS and 0.12 µm for manual cataract surgery ( P = .005). There were no significant differences in vision quality between treatments ( P = .40). All eyes (n = 15) with satisfaction scores of 0 to 10 had internal coma < 0.20 µm, compared to those with scores of 11 to 20 (27 of 29 eyes, 93.1%), 21 to 30 (19 of 30 eyes, 63.3%), and > 30 (8 of 15 eyes, 53.3%) ( P < .001). The average internal coma increased by a greater amount for manual cataract surgery than for FLACS for every increase in mesopic pupil size > 5.75 mm. CONCLUSIONS: More eyes achieved internal coma < 0.32 µm following FLACS compared to manual cataract surgery. However, this does not account for improved patient-reported vision quality. There was a correlation between internal coma and patient-reported satisfaction, and eyes with excellent patient satisfaction all had internal coma < 0.20 µm. [ J Refract Surg . 2019;35(2):102–108.]
Purpose To compare postoperative refractive outcomes in angle-closure eyes having phacoemulsification and intraocular lens (IOL) implantation with or without endocyclophotocoagulation (ECP). Setting Single tertiary-level ophthalmology practice. Design Retrospective comparative study. Methods Primary angle-closure suspect (PACS), primary angle-closure (PAC), or primary angle-closure glaucoma (PACG) eyes that had phacoemulsification and IOL implantation with or without ECP from 2012 to 2014 were studied. Clinical data collected included axial length (AL), minimum and maximum keratometry (K) values, corneal powers, anterior chamber depth (ACD), corneal white-to-white (WTW), implanted IOL power, and postoperative manifest refraction. The Holladay 1 formula was used for IOL calculations. Primary and secondary outcome measures were the mean absolute error (MAE) and mean arithmetic error, respectively. Results Sixty-eight eyes with ECP and 71 eyes without ECP were included. There were no statistically significant differences between the 2 groups in age, sex, eye side, ethnicity, AL, minimum or maximum keratometry values, ACD, WTW, or implanted IOL power. The MAE was lower in the non-ECP group (0.47 ± 0.32D versus 0.62 ± 0.43D; P = .0285). The mean arithmetic error showed a more myopic result in the ECP group (−0.54 ± 0.53D versus −0.26 ± 0.52D; P = .0017). Conclusion In this study, patients with PACS, PAC, or PACG having phacoemulsification and IOL implantation with ECP had decreased predictability of the postoperative refraction and a small myopic shift compared with those without ECP. Financial Disclosure Dr. Ahmed is a consultant to Alcon, Advanced Medical Optics, Bausch & Lomb, and Carl Zeiss. None of the other authors has a proprietary or financial interest in any material or method mentioned.
We read the article entitled ‘Gender differences in biometry prediction error and intra-ocular lens power calculation formula’ (Behndig et al. 2014) with interest. Authors analysed biometry prediction error (BPE) in a large Swedish cataract surgery registry and found 0.1D greater BPE in females over males where the SRK/T formula was utilized (n = 3171), though found no difference when Haigis formula (n = 2883) was used. This effect decreased over the study period. We value the sample size, though caution that large sample size can lead to spurious positive p-values (Lin et al. 2013). Regarding gender differences in BPE, we have not seen this in our own research and hypothesize that extremes in axial length (AL) are a potential confounder that may be driving the small difference found between the two genders. We recently published a study looking at factors associated with BPE in a large sample of patients undergoing bilateral cataract surgery at our Canadian centre between September 2013 and August 2015 and focused on AL and keratometry as potential drivers of BPE (Kansal et al. 2018). To elucidate whether gender was associated with BPE in our sample, we reanalysed our database of 1458 eyes (Table 1). Using Holladay 1 as our IOL formula, and generalized estimating equations to account for within-patient correlation between eyes, we found no statistically significant gender differences for overall BPE (female 0.34 ± 0.31D, male 0.33 ± 0.34D; p = 0.437). Furthermore, we found no gender differences for being within 0.25 D (female 45.5% versus male 49.3; p = 0.165), 0.50 D (female 78.9% vs. male 79.2%; p =0.886) and 1.00 D (female 97.1% vs. male 97.3%; p = 0.449) of the refractive target. Axial length is a strong predictor of BPE, specifically extremes in AL (Berk et al. 2018). Behnig et al. report significant gender differences in AL (female 23.45 ± 1.20 mm vs. male 24.01 ± 1.22 mm, p < 0.001). Given the known impact of AL on refractive outcomes, this confounder could be stratified against, similar to what they did for keratometry. While in our sample we did not find a difference by gender, it is possible that gender differences in AL are confounding the results. As such, we stratified our patients by AL ≤22, 22–25, >25 mm and still found no difference for each stratum; AL <22 mm (female 0.38 ± 0.33D versus male 0.33 ± 0.37D; p = 0.319), AL 22-25 mm (female 0.30 ± 0.26D versus male 0.28 ± 0.23D; p = 0.078) and AL > 25 mm (female 0.42 ± 0.43D versus male 0.42 ± 0.44D; p = 0.914). Additionally, to explore the trend over time, the authors could have evaluated whether the distribution of ALs changed over time (i.e. more hyperopes and myopes in a given year would lead to a higher BPE). The similar overall standard deviation in AL for the two gender groups implies there was not a significant difference in variation, though there could still be trends in axial length that are buried in that aggregate measure of variability that could explain the BPE differences. We also question the clinical significance of the 0.1D difference found. Results would be more useful if authors reported the proportion of patients outside of clinically relevant BPE targets, such as 0.5D and 1.0D (Hoffer et al. 2015). Manufacturing tolerances for intra-ocular lenses (IOL) are required to be within only ± 0.50D of the labelled IOL power, or within ± 1.00D for IOLs greater than 30D (Hoffer & Savini 2017), and spectacle/contact lens correction is accurate within 0.25D. In summary, we would be interested in further analysis on this topic: stratifying or performing regression on any potential confounders of this relationship, and the reporting of the results using clinically meaningful categorical cut points.
