Clinical and Experimental Ophthalmology最新文献

Background: To evaluate the safety of repeated low-level red-light (RLRL) therapy in children, and the dynamic evolution of choroidal and retinal blood flow.

Methods: This is a single-centre, randomised, single-blind, parallel-group clinical trial. Seventy myopic children were randomly assigned to either the intervention group [receiving RLRL therapy plus single-vision spectacle (SVS)] or the control group (wearing SVS). Participants underwent comprehensive ophthalmic examinations following their first irradiation, 9 months continuous RLRL therapy and stop of treatment. Quantitative analyses of choroidal and retinal microcirculation were analysed via optical coherence tomography angiography.

Results: Over 9 months of treatment, while the RLRL treatment demonstrated significantly less increases in refractive error and axial length compared with the SVS treatment (ps < 0.05), no abnormalities in fundus structure or visual function (mfERG, VEP and microperimetry) were detected (ps > 0.05). A single red-light exposure did not exert a significant influence on choroidal thickness (ps > 0.05). Upon continuous treatment, the RLRL group achieved peak values in these circulations at 9 months (ps < 0.05). Following cessation of exposure, all circulations exhibited a declining trend, reaching similar levels in both groups (ps > 0.05). As the frequency of red-light exposures intensified, there was a consistent surge in these circulations (ps < 0.05).

Conclusions: Nine months of continuous RLRL exposure does not cause toxic side effects on retinal or optic nerve functions, and there is a time-dependent cumulative response in choroidal and retinal circulation.

Background: A high-frequency point-of-care (POC) ultrasound instrument was used to evaluate the microstructural and biomechanical properties of the anterior sclera in vivo using parameters computed from quantitative ultrasound (QUS) methods.

Methods: In this cross-sectional study, both eyes of 85 enrolled patients were scanned with the POC instrument and ultrasound data were processed to obtain QUS parameters. Pearson correlation and multi-linear regression were used to identify relationships between QUS parameters and refractive error (RE) or axial length. After categorising eyes based on RE, binary support vector machine (SVM) classifiers were trained using the QUS or ophthalmic parameters (anterior chamber depth, central corneal thickness, corneal power, and intraocular pressure) to classify each eye. Classifier performance was evaluated by computing the area under the receiver-operating characteristic curve (AUC).

Results: Individual QUS parameters correlated with RE and axial length (p < 0.05). Multi-linear regression revealed significant correlation between the set of QUS parameters and both RE (R = 0.49, p < 0.001) and axial length (R = 0.46, p = 0.001). Classifiers trained with QUS parameters achieved higher AUC (𝑝 = 0.06) for identifying myopic eyes (AUC = 0.71) compared to classifiers trained with ophthalmic parameters (AUC = 0.63). QUS-based classifiers attained the highest AUC when identifying highly myopic eyes (AUC = 0.77).

Conclusions: QUS parameters correlate with progressing myopia and may be indicative of myopia-induced microstructural and biomechanical changes in the anterior sclera. These methods may provide critical clinical information complementary to standard ophthalmic measurements for predicting myopia progression and risk assessment for posterior staphyloma formation.

Background: To assess topical dorzolamide as medical therapy for idiopathic full-thickness macular holes (FTMHs).

Methods: Randomised, double-blinded, placebo-controlled, single-centre clinical trial involving 32 patients with idiopathic small FTMHs (<400 $\mathrm{\mu m}$ ). Participants in both arms used topical dorzolamide 2% or saline thrice daily for 8 weeks with monthly OCT. Those with persisting FTMH underwent vitrectomy with ILM peel and gas tamponade. The primary outcome was the rate of FTMH closure at the end of treatment.

Results: Between 6 March 2020 and 16 June 2023, 32 eligible patients were enrolled: 16 participants in each arm. All participants in both groups were included in the final analysis. At the final visit, 3 of 16 (18.8%) patients in both the topical dorzolamide and placebo group demonstrated closure. There was no statistically significant difference in the proportion of FTMH closure between the control and treatment group (p = 1.00), nor statistically significant difference in the mean change in best corrected visual acuity (BCVA; p = 0.909). There was no difference in the change in FTMH diameter between groups (p = 0.225). No serious adverse events were reported in either group.

Conclusion: Topical dorzolamide was safe but not superior to placebo in the functional and anatomical outcomes of FTMH.

Background: To assess changes in ocular biometry of the phakic eye after pars-plana-vitrectomy (PPV) and silicone oil (SO) endotamponade in eyes with a retinal detachment.

Methods: This retrospective, consecutive case series included 72 eyes of 72 patients who underwent PPV with 5000-centistokes SO endotamponade between July 2018 and June 2023. Pseudophakic eyes and eyes with a combined phacovitrectomy were excluded. Primary endpoints were keratometry values, anterior chamber depth (ACD), lens thickness (LT), horizontal corneal diameter (HCD), and axial length (AL) measured by swept-source optical coherence tomography-based biometry (IOLMaster 700) preoperatively and six weeks postoperatively. A recently described formula was used to adjust the AL (aAL) in eyes with SO endotamponade and a theoretical intraocular lens (IOL) calculation was performed.

Results: The mean age was 62.1 ± 8.3 years (range: 37-85). After PPV with SO fill, there was an increase in K_mean (0.19 ± 0.51D), while ACD (0.05 ± 0.13 mm), LT (0.03 ± 0.14 mm), and HCD (0.02 ± 0.24 mm) decreased. Preoperatively, the mean AL was 25.22 ± 1.78 mm, while postoperatively the AL was overestimated by 0.12 ± 0.42 mm on average (p = 0.04). By adjusting the AL, the mean difference could be reduced to -0.002 ± 0.41 mm. The aAL resulted in a difference in the refractive outcome in eyes with an AL > 25 mm of 0.34 ± 0.10D in the IOL calculation.

Conclusions: While changes in biometry after PPV with SO endotamponade in the anterior segment are clinically less relevant, a considerable overestimation of AL with IOLMaster 700 was found. We recommend the use of a recently introduced formula for adjusting AL in eyes with SO, allowing overestimation to be minimised considerably.

Background: To evaluate repeatability and agreement in measurements of total corneal astigmatism (TCA) in keratoconic eyes, using four optical coherence tomography (OCT)-based devices: Anterion, Casia SS-1000, IOLMaster 700, and MS-39.

Methods: Three consecutive measurements were taken with each device in 136 eyes. TCA values were converted into components J₀ and J₄₅. The Anterion and the IOLMaster 700 also provided axial length (AL) measurements. The repeatability was calculated using pooled within-subject standard deviation (S_w). The agreement among the four devices was assessed by pairwise comparisons and Bland-Altman plots.

Results: For all devices, the repeatability of TCA measurements showed S_w ≤0.23 D for TCA magnitude, ≤0.14 D for J₀, and ≤0.12 D for J₄₅. There were statistically significant differences in TCA magnitude for each pair, except for IOLMaster 700 with MS-39, and Anterion with MS-39. The repeatability (S_w) of axis measurements had a statistically significant negative correlation with the TCA magnitude (p < 0.001 for all devices). Both Anterion and IOLMaster 700 had high repeatability in AL measurements (S_w: 0.007 mm for Anterion and 0.009 mm for IOLMaster 700). The difference in AL between the two was 0.015 ± 0.033 mm (p < 0.001).

Conclusions: All four devices showed good repeatability in TCA measurements in keratoconic eyes, the agreement for TCA measurements between the tested devices was generally low. Anterion and IOLMaster 700 showed good repeatability and agreement in AL measurements.

Background: To evaluate current practice patterns of Immediate Sequential Bilateral Cataract Surgery (ISBCS) by ophthalmologists in Singapore and assess their attitudes towards performing ISBCS in future cataract care.

Methods: An anonymised electronic survey, modified to local context from a similar study conducted in the United Kingdom, was distributed to members of the College of Ophthalmologists, Academy of Medicine, Singapore, from 20 June to 1 September 2023. An initial screening question on prior experience with ISBCS directed the rest of the survey. Questions explored ophthalmologists' current ISBCS practice patterns and the importance of factors affecting their willingness to perform ISBCS. Results were descriptively analysed.

Results: Results collated 2 months upon survey dissemination saw a total of 58 respondents from 235 eligible members (24.7% response rate). Of these, 16 (27.6%) were currently performing ISBCS, 37 (63.8%) had never performed, and 5 (8.6%) had stopped performing. In considering ISBCS, patient convenience (n = 11, 68.8%) and reduced hospital visits (n = 8, 50.0%) were the most important factors nominated. The most important barriers to performing ISBCS were medico-legal issues (n = 31, 83.8%) and risk of endophthalmitis (n = 27, 73.0%), followed by perceived lack of evidence for its effectiveness (n = 19, 51.4%).

Conclusion: This is one of the first studies evaluating ophthalmologists' sentiments towards performing ISBCS in an Asian country. It highlights some of the most pertinent barriers and concerns that ophthalmologists face in performing and offering ISBCS. This study provides a better understanding of the potential role and prospects of ISBCS in future cataract care in Singapore.

Background: Paediatric vitreoretinal pathology is distinct from adult cases in both presentation and surgical planning. Here we aim to report the aetiology and epidemiology in children 0-18 years requiring vitreoretinal surgery at a major tertiary paediatric hospital in Queensland, Australia.

Methods: Retrospective review of cases requiring vitreoretinal surgery between May 2015 and October 2022 was conducted. Demographics, ocular and medical history, surgical pathology, procedures performed, and epidemiology data were retrieved. Patients were grouped into three main aetiologies: traumatic, syndromic, or secondary.

Results: A total of 124 patients, the majority male (87, 70.2%) with a mean age of 10.3 years underwent vitreoretinal surgery. Trauma accounted for 32.3% of cases requiring surgery of which 47% were due to a penetrating eye injury. 35.5% were associated with a syndromic cause with common aetiology including coats, congenital cataract, sticklers, and retinopathy of prematurity. 32.3% developed secondary pathology and retinal detachment was the primary cause for surgery (55%). The average time from symptom onset to presentation was 30 days (SD 56.88) with patients living an average of 306.2 km (SD 558.9) away from the Queensland Children's Hospital. Older age was significantly associated with increased days to presentation in the traumatic group (p < 0.05).

Conclusions: This study provides an insight into the aetiology and epidemiology of paediatric vitreoretinal presentations in Queensland, Australia.

Background: Patients in rural Australia have limited access to intravitreal treatments due to a maldistribution of the ophthalmology workforce. To improve access, a novel outreach service model was implemented whereby junior medical staff administered intravitreal injections under a supervising ophthalmology consultant. This model involves outreach visits in hospitals, mobile clinics and a remote hub with intravitreal injections administered by junior doctors overseen by an ophthalmologist. The article explores the safety of this approach with respect to the rate of post-injection endophthalmitis.

Methods: A retrospective audit was conducted by the Lions Outback Vision outreach ophthalmology service from 2017 to mid-2023. The number of injections, locations, diagnoses, intravitreal agents used, designation of administering doctor and cases of endophthalmitis were reviewed.

Results: A 12 632 intravitreal injections were administered across 32 locations throughout rural Western Australia in the 6.5-year period. Three cases of endophthalmitis occurred representing a rate of 0.0237%.

Conclusion: The rate of endophthalmitis in the outreach service is comparable to other centres. The outreach model with supervising ophthalmology consultant support in person or via telehealth and administration of injections by junior medical staff has improved access for underserved or marginalised populations.