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PurposeTo describe a surgical approach that involves anterior segment reconstruction with CustomFlex Artificial Iris (CAI; HumanOptics, Erlangen, Germany) followed by Descemet membrane endothelial keratoplasty (DMEK) in complex eyes with corneal decompensation.MethodsRestrospective case series of eyes that underwent anterior segment restoration involving (1) synechiolysis of peripheral anterior synechiae and excision of iris remnants, (2) securing a well-fixated posterior chamber intraocular lens and (3) suture-fixated or capsular bag placement of CAI. All eyes then underwent DMEK using a pull-through technique with the DMEK EndoGlide (Network Medical Products, Ripon, UK). Main outcomes were successful anterior segment restoration and corneal clarity with central corneal thickness (CCT).ResultsFive eyes of five patients (median age 61 years, range 27–69 years; 60% female) underwent anterior segment reconstruction with CAI implantation (4 suture-fixated), followed by successful DMEK surgery (median 2 months later, range 1–5 months). There were no major intraoperative complications or primary graft failure, with one peripheral graft detachment that underwent a successful re-bubble at 1 week. All eyes had stable CAI implants and DMEK grafts remained clear at last follow-up with reduction in mean central corneal thickness (preoperative: 658±86 µm vs postoperative: 470±33 µm, p=0.005).ConclusionThis pilot study highlights a feasible approach of initial anterior segment reconstruction with CAI implantation, prior to DMEK, in eyes with significant anterior segment abnormalities such as iris damage or extensive peripheral anterior synechiae and corneal decompensation.

Myopia is an emerging public health issue with potentially significant economic and social impact, especially in East Asia. However, many uncertainties about myopia and its clinical management remain. The International Myopia Summit workgroup was convened by the Singapore Eye Research Institute, the WHO Regional Office for the Western Pacific and the International Agency for the Prevention of Blindness in 2019. The aim of this workgroup was to summarise available evidence, identify gaps or unmet needs and provide consensus on future directions for clinical research in myopia. In this review, among the many ‘controversies in myopia’ discussed, we highlight three main areas of consensus. First, development of interventions for the prevention of axial elongation and pathologic myopia is needed, which may require a multifaceted approach targeting the Bruch’s membrane, choroid and/or sclera. Second, clinical myopia management requires co-operation between optometrists and ophthalmologists to provide patients with holistic care and a tailored approach that balances risks and benefits of treatment by using optical and pharmacological interventions. Third, current diagnostic technologies to detect myopic complications may be improved through collaboration between clinicians, researchers and industry. There is an unmet need to develop new imaging modalities for both structural and functional analyses and to establish normative databases for myopic eyes. In conclusion, the workgroup’s call to action advocated for a paradigm shift towards a collaborative approach in the holistic clinical management of myopia.

AimTo evaluate the outcomes and complications of hybrid Descemet membrane endothelial keratoplasty (H-DMEK) using a Descemet stripping automated endothelial keratoplasty (DSAEK) pull-through donor inserter and donor stroma as carrier.MethodsThis was a retrospective interventional case series of eyes with bullous keratopathy (BK) and Fuchs endothelial corneal dystrophy (FECD), which underwent H-DMEK, performed using a bimanual pull-through technique using DSAEK-prepared donor stroma as carrier and the EndoGlide Ultrathin DSAEK donor insertion device. Complex cases with tube shunts, trabeculectomy, aphakia, aniridia, previous vitrectomy, keratoplasty or combined with intraocular lens exchange, were also included. The outcome measures were intraoperative and postoperative complications, best corrected visual acuity (BCVA) and endothelial cell loss after surgery.ResultsOf the 85 eyes from 79 patients, 43.5% (n=37) had BK, 28.2% (n=24) had FECD while 24.7% (n=21) had failed grafts. DMEK was performed in 37 complex eyes (43.5%). Four eyes (4.7%) required rebubbling for graft detachment and two cases of graft failure were observed. A BCVA of 20/25 or better was attained in 44.7% and 57.1% of eyes without pre-existing ocular pathology at 6 and 12 months, respectively. The overall endothelial cell loss was 32.2%±20.5% at 6 months, which improved from 37.2%±20.9% to 24.2%±17.5%, comparing the first 40 and last 45 cases (p=0.012).ConclusionHybrid DMEK offers a controlled ‘pull-through’ technique of donor insertion in the ‘endothelium-in’ configuration, which may be useful especially in complicated eyes. More studies are needed to confirm the long-term endothelial cell loss and graft survival associated with this technique.

Aim To describe the histological features of Cytomegalovirus (CMV)-related corneal graft infections, its associated features and clinical significance. Methods This was a retrospective histological study of 48 consecutive cases of failed repeat penetrating keratoplasty cases with a clinical diagnosis of allograft rejection from 2011 to 2013. CMV infection was confirmed with CMV antibody immunohistochemistry (IHC) and electron microscopy. Additional CD163 and CD68 IHCs for macrophages were also performed. Clinical data and previous graft histology were then reviewed. Results Mean incidence of CMV infection in corneal graft rejection buttons was 6.3% per year. 3/48 graft buttons were CMV antibody positive. Histological features of CMV graft infection include: (1) stromal keratocytes with cytopathic changes; (2) lack of inflammation, only occasional macrophages present and (3) absence of vascularisation. None of the patients had a history of active CMV infection. Conclusion CMV infection is not limited as endotheliitis, but extends into the corneal stroma, and is a potential reservoir for graft infection, especially in partial thickness endothelial surgery. Clinical features are often non-specific, although glaucoma was present in our patients. CMV-infected grafts showed CD163-positive M2 macrophages in close association with the infected keratocytes, suggesting that the macrophage may be important in CMV graft infection. Histological examination with CMV IHC is a useful method to detect CMV infection postoperatively. Post penetrating keratoplasty, CMV systemic treatment with valganciclovir can prevent graft infection and failure. Boston keratoprosthesis may be a potential alternative surgery in active CMV infections that obviates the need for systemic therapy.

Descemet membrane endothelial keratoplasty (DMEK) allows for selective replacement of damaged endothelial cells, using only donor Descemet's membrane with endothelium. However, early adoption by corneal surgeons has been limited (illustrated by graft registry reports: 0.7% all corneal transplants in the USA; 0.4% in Australia for 2011) due to challenges in donor preparation and surgical technique. Recently, innovative donor preparation techniques may improve availability of pre-stripped DMEK donors from eye banks. The refinement of donor insertion and manipulation techniques has also improved outcomes and reduced graft detachment rates—still, the most common postoperative complication following DMEK. Randomised studies are needed to compare clinical practices and surgeon preferences, such as intraoperative use of long- acting gas, early versus late intervention of graft detachments and postoperative steroid management. A review of current literature reveals that most publications to date are reports from similar study cohorts by surgeons who pioneered and advocate this technique. Thus, more long-term clinical studies in other tertiary centres are required in order to confirm if the purported advantages of DMEK such as improved visual outcomes and reduced graft rejection are replicable among most corneal surgeons.

Dear Editor, We thank Mittal and Garg for their interest in our publication. Our study analysed Descemet's stripping automated endothelial keratoplasty (DSAEK) with anterior chamber intraocular lenses (ACIOL) with regards to 3-year graft survival and endothelial cell loss as our main outcome measures, not visual outcome or complications.1 Here, we used Kaplan–Meier survival analysis that takes into account any censored data from loss to follow-up, to derive that there was a significantly poorer graft survival in the DSAEK-ACIOL group versus the DSAEK group (log-rank p=0.002). In fact, completely excluding subjects …

Aim To compare visual outcomes between deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK). Secondarily to compare refractive outcomes, complications and graft survival between the three cohorts. Methods Retrospective case-control study evaluating visual acuity outcomes (VA) following DALK with complete Descemet9s baring (DALKa) (modified Anwar big bubble technique—51 eyes), pre-descemetic anterior lamellar keratoplasty (DALKm) (manual technique—52 eyes) and PK (103 eyes) with mean follow-up of 13.6, 19.3 and 18.6 months, respectively. Results The common indications for surgery were corneal scars (36.4%), keratoconus (28.6%) and corneal dystrophies (13.6%). A best-corrected VA of 6/7.5 or better was achieved in 19.4% (PK), 21.6% (DALKm) and 38.5% (DALKa) of cases (p=0.02), and eyes that underwent DALKa had significantly better visual outcomes than PK (p=0.03). Complications following PK were glaucoma (15%), endothelial rejection (12%) and epithelial problems (11%); in the lamellar group, glaucoma (9%), epithelial problems (5%) and Descemet9s detachment (3%) were more common. The 2-year estimated probability of graft survival was 90% for PK, 98% for DALKm and 100.0% for DALKa (p=0.35). Conclusions Lamellar keratoplasty with complete baring of the Descemet9s membrane (DALKa) gave significantly better visual outcomes compared to PK or pre-descemetic ALK and should be the preferred from of corneal replacement in corneal disorders with healthy endothelium.

Aim: The aim of this study was to determine if topical atropine, used to retard axial length elongation and myopia progression, had any effect on ocular astigmatism. Methods: Data collected from subjects enrolled in the Atropine in the Treatment of Myopia (ATOM) study were analysed. In this study, 400 myopic children (aged 6–12 years) were randomly assigned to administer atropine 1% or a placebo daily to a randomly selected eye for 2 years. Cycloplegic autorefraction and keratomy readings were measured using a Canon RK5 autorefractor. The refractive error was then split into its power vector components: J0 and J45. Results: Astigmatism increased by 0.12–0.16 D per year in both treated and placebo groups. There was no difference between groups (p = 0.182). The increase was mirrored by an increase in corneal astigmatism of 0.10–0.13 D per year, suggesting that most of the change was corneal in nature. There was an increase in J0 vector (with-the-rule astigmatism) with no change in the J45 (oblique) vector over time. The change in the J0 vector was significantly larger in the atropine-treated versus atropine-untreated eyes during the 2-year treatment period (p = 0.011), but this difference disappeared after atropine was stopped. Conclusion: The use of atropine on a daily basis over 2 years did not have any clinically significant effect on astigmatism.

Aim: The aim of the study was to describe the prevalence and visual outcomes of cataract surgery in an urban Asian population. Methods: This was a population-based study of 3280 Singapore Malays aged 40–80 years (response rate 78.7%). Participants had a standardised interview and comprehensive ocular examination. Poor post-operative visual outcome was defined as visual acuity ⩽20/60 in operated eyes of unilateral cataract extractions or in the better-seeing eye of bilateral cataract extractions. Factors associated with poor visual outcome were assessed. Results: Of 3280 participants, 284 (men 52.3%) had unilateral cataract extractions (age-standardised prevalence 4.7%, 95% CI 4.2% to 5.4%) and 154 persons (54%) had bilateral extractions. Older age, male sex and the presence of diabetes were significant factors associated with having had cataract surgery. Poor visual outcomes were present in 10.8% of the operated eyes using best-corrected visual acuity. Diabetic retinopathy (25.5%), glaucoma (17%), age-related macular degeneration (14.9%) and posterior capsular opacification (14.9%) were the main causes of poor visual outcome after surgery. Under-corrected refractive error accounted for 60% of patients with post-operative presenting visual acuity of ⩽20/60. Conclusions: Five per cent of the sample of the Malay population aged 40–80 years in Singapore had cataract surgery. One in ten had post-operative best-corrected visual acuity of 20/60 or worse, largely related to concomitant retinal diseases.

Aims: To determine the associations between corneal biomechanical parameters as measured by the Reichert Ocular Response Analyser (ORA) and disc morphology and retinal nerve fibre layer thickness (RNFL) measured by the Heidelberg Retinal Tomograph (HRT) II in Singaporean children. Methods: This is a cross-sectional study conducted on a subset of children enrolled in the Singapore Cohort Study of the Risk Factors of Myopia (SCORM). Corneal hysteresis (CH), corneal resistance factor (CRF) and central corneal thickness (CCT) were measured with the ORA. Optic disc morphology and RNFL thickness were assessed by the HRT II. Cycloplegic refraction and ultrasound A-scans were also performed, and disc tilt was assayed from stereo photographs. Results: 102 subjects (mean age 12.01 (SD 0.57) years; range 11–14 years) were included in the study. The mean CH was 12.00 (1.40) mm Hg, the mean CRF was 11.99 (1.65) mm Hg, and the mean CCT was 581.12 (33.53) μm. Eyes with tilted discs had significantly longer axial lengths and more myopic refraction than eyes without tilted discs. There were no significant correlations between CH, CRF or CCT and the HRT II parameters, after the application of the Bonferroni correction. When stratified for disc tilt, however, the global disc area was significantly correlated with CCT (r = −0.49, p = 0.001). Conclusion: Corneal biomechanical properties as measured with the ORA do not vary with optic disc parameters or RNFL. Central corneal thickness is correlated with disc area in Singaporean schoolchildren with tilted discs. This relationship may influence glaucoma risk in myopic subjects.

Aims: To describe the long-term risk of bullous keratopathy following argon laser iridotomy (ALI) in Japan and to compare it with other centres in the world. Methods: We retrospectively reviewed the case records of all patients with ALI-induced bullous keratopathy that underwent penetrating keratoplasty at Kyoto Prefectural University of Medicine (KPUM) from January 2001 to December 2004. The results were compared with the other representative centres in Singapore and the UK. Results: Thirty-nine eyes of 33 patients were included in the study. The mean age of patients was 73.3±6.9 years (range, 58 to 87 years). Patients developed bullous keratopathy at a mean duration of 6.9±4.9 years (range, 0.2 to 16 years) after the laser iridotomy procedure. The majority of eyes that developed bullous keratopathy (59.0%) occurred following prophylactic ALI. KPUM had the highest percentage of ALI-induced bullous keratopathy cases that underwent penetrating keratoplasties, as compared with other centres in Singapore and the UK (20.0%, 1.8% and 0%, respectively). Conclusion: Bullous keratopathy may arise many years following ALI, and is a growing problem in Asian countries. This condition is a major cause of ocular morbidity in Japan, which has seen a worrying increase in the number of cases in recent years.

To compare the prevalences of refractive errors in Malay, Chinese and Indian children in Malaysia and Singapore.Children aged 7-9 years from three schools in the Singapore Cohort study of the Risk factors for Myopia (n = 1962) and similarly aged children from a random cluster sample in the metropolitan Kuala Lumpur area in the Malaysia Refractive Error Study in Children (n = 1752) were compared. Cycloplegic autorefraction was conducted in both countries.The prevalence of myopia (spherical equivalent of at least -0.5 diopters (D) in either eye) was higher in Singapore Malays (22.1%) than in Malays in Malaysia (9.2%; 95% confidence interval (CI) 11.2 to 14.7; p0.001). Similarly, Singapore Chinese (40.1%) had higher prevalences than Malaysian Chinese (30.9%; 95% CI 1.5 to 16.9). Singapore Indians had a higher prevalence (34.1%) than Malaysian Indians (12.5%; 95% CI 17.4 to 25.9). The multivariate odds ratio of astigmatism (cylinder at least 0.75 D in either eye) in Singapore Malays compared with Malaysian Malays was 3.47 (95% CI 2.79 to 4.32). Ethnicity-specific hyperopia rates did not differ in Singapore and Malaysia.The ethnicity-specific prevalences of myopia in Singapore Malays, Chinese and Indians are higher than those in Malaysian Malays, Chinese and Indians. As Malays, Chinese and Indians in Malaysia have genetic make-up similar to that of Malays, Chinese and Indians in Singapore, environmental factors may contribute to the higher myopia rates.

Aim: To determine the prevalence rates and major contributing causes of low vision and blindness in adults in a rural setting in Indonesia Methods: A population based prevalence survey of adults 21 years or older (n=989) was conducted in five rural villages and one provincial town in Sumatra, Indonesia. One stage household cluster sampling procedure was employed where 100 households were randomly selected from each village or town. Bilateral low vision was defined as habitual VA (measured using tumbling “E” logMAR charts) in the better eye worse than 6/18 and 3/60 or better, based on the WHO criteria. Bilateral blindness was defined as habitual VA worse than 3/60 in the better eye. The anterior segment and lens of subjects with low vision or blindness (both unilateral and bilateral) (n=66) were examined using a portable slit lamp and fundus examination was performed using indirect ophthalmoscopy. Results: The overall age adjusted (adjusted to the 1990 Indonesia census population) prevalence rate of bilateral low vision was 5.8% (95% confidence interval (CI) 4.2 to 7.4) and bilateral blindness was 2.2% (95% CI 1.1 to 3.2). The rates of low vision and blindness increased with age. The major contributing causes for bilateral low vision were cataract (61.3%), uncorrected refractive error (12.9%), and amblyopia (12.9%), and the major cause of bilateral blindness was cataract (62.5%). The major causes of unilateral low vision were cataract (48.0%) and uncorrected refractive error (12.0%), and major causes of unilateral blindness were amblyopia (50.0%) and trauma (50.0%). Conclusions: The rates of habitual low vision and blindness in provincial Sumatra, Indonesia, are similar to other developing rural countries in Asia. Blindness is largely preventable, as the major contributing causes (cataract and uncorrected refractive error) are amenable to treatment.