Publications by authors named "Chee Wai Wong"

64 Publications

Retinal microvascular signs in COVID-19.

Br J Ophthalmol 2021 Mar 19. Epub 2021 Mar 19.

Singapore National Eye Centre, Singapore.

Background/aims: To explore if retinal findings are associated with COVID-19 infection.

Methods: In this prospective cross-sectional study, we recruited participants positive for COVID-19 by nasopharyngeal swab, with no medical history. Subjects underwent retinal imaging with an automated imaging device (3D OCT-1 Maestro, Topcon, Tokyo, Japan) to obtain colour fundus photographs (CFP) and optical coherence tomographic (OCT) scans of the macula. Data on personal biodata, medical history and vital signs were collected from electronic medical records.

Results: 108 patients were recruited. Mean age was 36.0±5.4 years. 41 (38.0%) had symptoms of acute respiratory infection (ARI) at presentation. Of 216 eyes, 25 (11.6%) had retinal signs-eight (3.7%) with microhaemorrhages, six (2.8%) with retinal vascular tortuosity and two (0.93%) with cotton wool spots (CWS). 11 eyes (5.1%) had hyper-reflective plaques in the ganglion cell-inner plexiform layer layer on OCT, of which two also had retinal signs visible on CFP (CWS and microhaemorrhage, respectively). There was no significant difference in the prevalence of retinal signs in symptomatic versus asymptomatic patients (12 (15.0%) vs 13 (9.6%), p=0.227). Patients with retinal signs were significantly more likely to have transiently elevated blood pressure than those without (p=0.03).

Conclusion: One in nine had retinal microvascular signs on ocular imaging. These signs were observed even in asymptomatic patients with normal vital signs. These retinal microvascular signs may be related to underlying cardiovascular and thrombotic alternations associated with COVID-19 infection.
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http://dx.doi.org/10.1136/bjophthalmol-2020-318236DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7985973PMC
March 2021

Is artificial intelligence a solution to the myopia pandemic?

Br J Ophthalmol 2021 Mar 12. Epub 2021 Mar 12.

Singapore National Eye Centre, Singapore

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http://dx.doi.org/10.1136/bjophthalmol-2021-319129DOI Listing
March 2021

Liposomal drug delivery system for anti-inflammatory treatment after cataract surgery: a phase I/II clinical trial.

Drug Deliv Transl Res 2021 Feb 10. Epub 2021 Feb 10.

Singapore National Eye Centre (SNEC), 11 Third Hospital Avenue, Singapore City, 168751, Singapore.

Liposomes as a drug delivery system may overcome the problems associated with non-compliance to eyedrops and inadequate control of inflammation after cataract surgery. We evaluated the safety and efficacy of a single subconjunctival injection of liposomal prednisolone phosphate (LPP) for the treatment of post-cataract surgery inflammation. This is a phase I/II, open-label non-comparative interventional trial of patients undergoing cataract surgery. All patients received a single injection of subconjunctival LPP intraoperatively. The primary outcome measure was the proportion of eyes with an anterior chamber cell count of 0 at postoperative month 1. Ocular and non-ocular adverse events, including elevated intraocular pressure, rebound iritis and pseudophakic macular edema were monitored. Five patients were enrolled in this study. The mean age was 66.6 ± 6.2 and 4 (80%) were male. The proportion of patients with AC cell grading of 0 was 0%, 80%, 80%, and 100% at day 1, week 1, month 1, and month 2 after cataract surgery, respectively. Mean laser flare photometry readings were significantly elevated at week 1 after cataract surgery (48.8 ± 18.9, p = 0.03) compared with baseline, decreasing to 25.8 ± 9.2 (p = 0.04) at month 1 and returned to baseline by month 2 (10.9 ± 5.1, p = 1.0). No ocular or non-ocular adverse events were observed. Liposomal prednisolone phosphate, administered as a single subconjunctival injection intraoperatively, can be a safe and effective treatment for post-cataract surgery inflammation. The delivery of steroids with a liposomal drug delivery system could potentially replace eyedrops as anti-inflammatory therapy following cataract surgery.
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http://dx.doi.org/10.1007/s13346-021-00912-xDOI Listing
February 2021

Genotypic Homogeneity in Distinctive Transforming Growth Factor-Beta Induced (TGFBI) Protein Phenotypes.

Int J Mol Sci 2021 Jan 27;22(3). Epub 2021 Jan 27.

Singapore National Eye Centre, Singapore 168751, Singapore.

To evaluate the distribution of the transforming growth factor-beta induced (TGFBI) corneal dystrophies in a multi-ethnic population in Singapore, and to present the different phenotypes with the same genotype. This study included 32 patients. Slit lamp biomicroscopy was performed for each patient to determine the disease phenotype. Genomic DNA was extracted from the blood samples and the 17 exons of the TGFBI gene were amplified by PCR and sequenced bi-directionally for genotype analysis. Regarding phenotypes, the study patients comprised 11 (34.4%; 8 with R555W and 3 with R124H mutation) patients with granular corneal dystrophy type 1 (GCD1), 6 (18.8%; 5 with R124H and 1 with R124C mutation) patients with GCD2, 13 (40.6%; 7 with R124C, 2 with H626R, 2 with L550P, 1 with A620D and 1 with H572R) patients with lattice corneal dystrophy (LCD) and 2 (6.3%; 1 with R124L and 1 with R124C) patients with Reis-Bückler corneal dystrophy. Regarding genotype, R124H mutation was associated with GCD2 (5 cases; 62.5%) and GCD1 (3 cases; 37.5%). R124C mutation was associated with LCD (7 cases; 87.5%) and GCD2 (1 case; 12.5%). All the 8 cases (100%) of R555W mutation were associated with GCD1. Although the association between genotype and phenotype was good in most cases (65.7%; 21 of 32 patients), genotype/phenotype discrepancy was observed in a significant number.
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http://dx.doi.org/10.3390/ijms22031230DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7866065PMC
January 2021

Quantitative OCT angiography of the retinal microvasculature and choriocapillaris in highly myopic eyes with myopic macular degeneration.

Br J Ophthalmol 2021 Jan 4. Epub 2021 Jan 4.

Singapore Eye Research Institute, Singapore National Eye Center, Singapore.

Purpose: To quantify retinal and choriocapillaris (CC) microvasculature in highly myopic (HM) eyes with myopic macular degeneration (MMD) using swept-source optical coherence tomography angiography (SS-OCTA).

Methods: 162 HM eyes (spherical equivalent ≤ -6.0 dioptres or axial length (AL) ≥26.5 mm) from 98 participants were enrolled, including 60 eyes (37.0%) with tessellated fundus, 54 eyes (33.3%) with peripapillary diffuse chorioretinal atrophy (PDCA), 27 eyes (16.7%) with macular diffuse chorioretinal atrophy (MDCA) and 21 eyes (13.0%) with patchy or macular atrophy. PLEX Elite 9000 SS-OCTA was performed to obtain perfusion densities (PD) of the superficial and deep retinal capillary plexus, and CC signal voids (number, area and density).

Results: Retinal PD decreased with increasing severity of MMD. Multivariable analysis showed that after adjustment of age and other factors, retinal PD decreased significantly in eyes with longer AL (β≤-0.51, p<0.001) and with an MMD severity of MDCA or worse (β≤-1.63, p<0.001). Reduced retinal PD were significantly associated with worse vision (β≤-0.01, p≤0.04). In terms of CC signal voids, multivariable analysis showed that longer AL (p<0.001), but not MMD severity (p≥0.12) was significantly associated with CC signal void changes in the earliest stage of MMD.

Conclusion: We demonstrate significant OCTA alterations in the retina and CC in HM eyes with varying severities of MMD. In eyes with early-stage PDCA, lower retinal PD and more extensive CC signal voids are predominantly associated with increasing AL. In contrast, in eyes with MDCA or worse, MMD itself was associated with sparser retinal and CC circulation.
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http://dx.doi.org/10.1136/bjophthalmol-2020-317632DOI Listing
January 2021

A review of the clinical applications of drug delivery systems for the treatment of ocular anterior segment inflammation.

Br J Ophthalmol 2020 Oct 30. Epub 2020 Oct 30.

Singapore National Eye Centre, Singapore

Ocular anterior segment inflammation is a medical problem that is seen in cases of cataract surgery and non-infectious anterior uveitis. Inadequately treated anterior segment inflammation can lead to sight-threatening conditions such as corneal oedema, glaucoma and cystoid macular oedema. The mainstay of treatment for anterior segment inflammation is topical steroid eye-drops. However, several drawbacks limit the critical value of this treatment, including low bioavailability, poor patient compliance, relatively difficult administration manner and risk of blurring of vision and ocular irritation. A drug delivery system (DDS) that can provide increased bioavailability and sustained delivery while being specifically targeted towards inflamed ocular tissue can potentially replace daily eye-drops as the gold standard for management of anterior segment inflammation. The various DDS for anti-inflammatory drugs for the treatment of anterior segment inflammation are listed and summarised in this review, with a focus on commercially available products and those in clinical trials. Dextenza, INVELTYS, Dexycu and Bromsite are examples of DDS that have enjoyed success in clinical trials leading to FDA approval. Nanoparticles and ocular iontophoresis form the next wave of DDS that have the potential to replace topical steroids eye-drops as the treatment of choice for anterior segment inflammation. With the current relentless pace of ophthalmic drug delivery research, the pursuit of a new standard of treatment that eliminates the problems of low bioavailability and patient compliance may soon be realised.
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http://dx.doi.org/10.1136/bjophthalmol-2020-315911DOI Listing
October 2020

Anti-retinal autoantibodies in myopic macular degeneration: a pilot study.

Eye (Lond) 2020 Oct 28. Epub 2020 Oct 28.

Singapore National Eye Centre, Singapore, Singapore.

Aim: The aim of this study is to evaluate the frequency and types of anti-retinal autoantibodies (ARAs) in highly myopic patients and to explore any association between ARAs and the severity of myopic macular degeneration (MMD).

Methods: This was a clinic-based study of 16 patients with high myopia (spherical equivalent worse than -6 dioptres or axial length (AL) ≥ 26.5 mm) recruited from the High Myopia clinic of the Singapore National Eye Centre. MMD was graded from fundus photographs according to the Meta-analysis for Pathologic Myopia (META-PM) classification. Severe MMD was defined as META-PM category 3 or 4. AL and logarithm of the minimal angle of resolution (logMAR) best corrected visual acuity (BCVA) were measured. Sera were obtained from subjects and analysed for the presence of ARAs with the western blot technique.

Results: The mean AL was significantly longer in patients with severe MMD (n = 8) than those without severe MMD (n = 8) (31.50 vs. 28.51, p = 0.005). There was at least one ARA identified in all patients. The most common ARA was anti-carbonic anhydrase II (anti-CAII), present in nine patients (56.3%). Anti-CAII was detected in more patients with severe MMD than those without (75 vs. 37.5%, p = 0.32). LogMar BCVA was also worse in subjects with anti-CAII (0.5 ± 0.38 vs. 0.22 ± 0.08, p = 0.06). The number of ARAs significantly correlated with increasing AL (r = 0.61, p = 0.012).

Conclusions: ARAs are prevalent in patients with high myopia, and this increases with increasing AL. In particular, anti-CAII antibodies were highly prevalent in patients with severe MMD, suggesting that ARAs may be associated with MMD. Further studies are necessary to confirm these observations in larger cohorts.
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http://dx.doi.org/10.1038/s41433-020-01241-yDOI Listing
October 2020

Endogenous or Exogenous Retinal Pigment Epithelial Cells: A Comparison of Two Experimental Animal Models of Proliferative Vitreoretinopathy.

Transl Vis Sci Technol 2020 08 31;9(9):46. Epub 2020 Aug 31.

Singapore National Eye Centre, Singapore.

Purpose: Proliferative vitreoretinopathy (PVR) is a blinding condition that can occur following ocular penetrating injury and retinal detachment. To develop effective therapeutics for PVR, it is imperative to establish an animal model that is reproducible, closest in anatomy to the human eye, and most representative of the human disease. We compared two in vivo models of PVR in minipig eyes to assess reproducibility and consistency.

Methods: Six minipigs underwent PVR induction with procedure A and six underwent procedure B. In both procedures, PVR was induced with vitrectomy, bleb retinal detachment, retinotomy, and injection of platelet-rich plasma. In procedure A, retinal pigment epithelial (RPE) cells were harvested from cadaveric pig eyes and injected at the end of surgery. In procedure B, native RPE cells were released into the vitreous cavity by creating a RPE detachment and scraping the RPE layer. PVR severity was graded on fundoscopic examination with a modified Silicone Study Classification System for PVR. Severe PVR was defined as stages 2 to 5.

Results: Three eyes (50%) and five eyes (83.3%) developed re-detachment of the retina from severe PVR in procedures A and B, respectively ( = 0.55). Median PVR stage was higher in eyes that underwent procedure B compared to eyes that underwent procedure A, although the difference was not statistically significant (2.5 vs. 1.5, = 0.26).

Conclusions: This new model utilizing native RPE cells achieved a high consistency in inducing severe PVR in the minipig.

Translational Relevance: Our model closely follows pathogenic events in human PVR, making it ideal for preclinical testing of novel therapeutics for PVR.
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http://dx.doi.org/10.1167/tvst.9.9.46DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7463202PMC
August 2020

Highlights from the 2019 International Myopia Summit on 'controversies in myopia'.

Br J Ophthalmol 2020 Aug 18. Epub 2020 Aug 18.

Singapore National Eye Centre, Singapore

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.
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http://dx.doi.org/10.1136/bjophthalmol-2020-316475DOI Listing
August 2020

Digital Screen Time During the COVID-19 Pandemic: Risk for a Further Myopia Boom?

Am J Ophthalmol 2021 03 30;223:333-337. Epub 2020 Jul 30.

Singapore National Eye Center, Duke-National University of Singapore Medical School, Singapore; Singapore Eye Research Institute, Singapore Health Service (SingHealth), Duke-National University of Singapore Medical School, Singapore. Electronic address:

Purpose: To review the impact of increased digital device usage arising from lockdown measures instituted during the COVID-19 pandemic on myopia and to make recommendations for mitigating potential detrimental effects on myopia control.

Design: Perspective.

Methods: We reviewed studies focused on digital device usage, near work, and outdoor time in relation to myopia onset and progression. Public health policies on myopia control, recommendations on screen time, and information pertaining to the impact of COVID-19 on increased digital device use were presented. Recommendations to minimize the impact of the pandemic on myopia onset and progression in children were made.

Results: Increased digital screen time, near work, and limited outdoor activities were found to be associated with the onset and progression of myopia, and could potentially be aggravated during and beyond the COVID-19 pandemic outbreak period. While school closures may be short-lived, increased access to, adoption of, and dependence on digital devices could have a long-term negative impact on childhood development. Raising awareness among parents, children, and government agencies is key to mitigating myopigenic behaviors that may become entrenched during this period.

Conclusion: While it is important to adopt critical measures to slow or halt the spread of COVID-19, close collaboration between parents, schools, and ministries is necessary to assess and mitigate the long-term collateral impact of COVID-19 on myopia control policies.
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http://dx.doi.org/10.1016/j.ajo.2020.07.034DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7390728PMC
March 2021

Correction: Design, implementation, and evaluation of a nurse-led intravitreal injection programme for retinal diseases in Singapore.

Eye (Lond) 2020 Nov;34(11):2151

Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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http://dx.doi.org/10.1038/s41433-020-1077-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7784974PMC
November 2020

Evaluation of Intraocular Pressure After Water Drinking Test in Patients with Unilateral Hemifacial Spasm.

Clin Ophthalmol 2020 18;14:1675-1680. Epub 2020 Jun 18.

Department of Cataract and Comprehensive Ophthalmology, Singapore National Eye Centre, Singapore.

Purpose: The aim of the study is to examine the baseline intraocular pressure (IOP) and its changes after performing a water drinking test (WDT) in patients with unilateral hemifacial spasm (HFS).

Patients And Methods: In this prospective observational study, patients aged 21 years and above diagnosed with unilateral HFS were recruited from the Singapore National Eye Centre between January 2015 and August 2016. The unaffected eye of each patient served as a matched control. An interviewer-administered standardized questionnaire on HFS symptoms and ophthalmic examination was performed. Automated perimetry, optical coherence tomography (OCT) of the optic nerve head, color disc stereophotography and water drinking test (WDT) were done. The primary outcome measure was the difference in IOP between eyes affected by HFS and fellow eyes at baseline and at 15, 30 and 45 minutes of the WDT.

Results: Fifty-four patients with unilateral HFS were included. Mean age was 59.8±9.9 years (range, 37.0-84.0). Of these, 54% were female and 94% were Chinese. Mean baseline IOP was significantly higher in eyes with HFS (13.9±3.1mmHg) compared to fellow eyes (13.3±2.8mmHg) (p=0.008). There was no significant difference in absolute or percentage change in IOP from baseline between the 2 groups at 15, 30 and 45 minutes of the WDT. Mean vertical cup-disc ratio (VCDR) on clinical examination was significantly higher in eyes with HFS (0.5±0.2) compared to fellow eyes (0.4±0.2) (p=0.02). There was no significant difference between the groups for visual field parameters and mean retinal nerve fiber layer thickness on OCT.

Conclusion: Hemifacial spasm is associated with a small but significant difference in mean baseline IOP and VCDR between affected and fellow eyes. However, when eyes affected by HFS and fellow eyes were challenged with the WDT, both responded in similar ways.
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http://dx.doi.org/10.2147/OPTH.S249943DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7308145PMC
June 2020

Prevalence, risk factors and impact of posterior staphyloma diagnosed from wide-field optical coherence tomography in Singapore adults with high myopia.

Acta Ophthalmol 2021 Mar 29;99(2):e144-e153. Epub 2020 Jun 29.

Singapore Eye Research Institute, Singapore, Singapore.

Purpose: To investigate the prevalence and risk factors of posterior staphyloma using wide-field optical coherence tomography (WF-OCT) in adults with high myopia in Singapore.

Design: Population-based cross-sectional study.

Methods: Adults with spherical equivalent (SE) ≤ -5D in either eye at the first visit of Singapore Epidemiology of Eye Diseases study and Singapore Prospective Study Program study were recruited. Posterior staphyloma was diagnosed using WF-OCT (PLEX Elite9000, Carl Zeiss Meditec). Myopic macular degeneration (MMD), myopic traction maculopathy (MTM) and vision-related quality of life (VRQoL) were assessed using fundus photographs, DRI-Triton OCT (Topcon) and the Impact of Vision Impairment (IVI) questionnaire, respectively. Factors associated with posterior staphyloma were identified with multilevel, multivariable logistic regression. Impact of posterior staphyloma on MMD, MTM and visual function was analysed with multilevel, multivariable logistic regression and linear mixed model, respectively.

Results: Among the 225 eyes [mean SE = -6.5 ± 2.2 D, mean axial length (AL) = 26.2 ± 1.5 mm] of 117 participants (mean age = 60.3 ± 7.1 years), posterior staphyloma was detected in 47 (20.9%) eyes of 38 (32.5%) participants. Older age [odds ratio (OR), 1.18; 95% confidence interval (CI), 1.10-1.26], more myopic SE (0.63; 0.51-0.77) and increased AL (2.51; 1.69-3.73) were associated with higher prevalence of posterior staphyloma (all p < 0.001). Adults with posterior staphyloma had higher odds of MMD (2.67; 1.23-5.82; p = 0.013), MTM (3.79; 1.13-12.68; p = 0.031) and worse IVI Reading (β = -1.44; -2.31 to 0.58; p = 0.001) scores.

Conclusions: About one in three adults with high myopia had posterior staphyloma, which was associated with increased odds of having myopic maculopathy and a detrimental impact on VRQoL.
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http://dx.doi.org/10.1111/aos.14527DOI Listing
March 2021

Characteristics of myopic traction maculopathy in myopic Singaporean adults.

Br J Ophthalmol 2021 Apr 23;105(4):531-537. Epub 2020 May 23.

Singapore Eye Research Institute, Singapore National Eye Centre, Singapore

Purpose: To investigate the characteristics, risk factors and visual impact of myopic traction maculopathy (MTM) among adults with myopia in Singapore.

Methods: We analysed 3316 myopic eyes of adults aged over 40 years who participated in the Singapore Epidemiology of Eye Diseases-2 study. Detailed questionnaires and ophthalmic examinations were conducted. A total of 2913 myopic eyes of 1639 subjects were graded for MTM by spectral-domain optical coherence tomography. MTM is defined as the presence of retinoschisis, lamellar or full-thickness macula hole and foveal retinal detachment. Fundus photographs were graded for myopic macular degeneration (MMD).

Results: Of these 2913 myopic eyes, the mean and SD of age was 60.1±8.0 years; the spherical equivalent (SE) was -2.5±2.3 D; and the axial length (AL) was 24.6±1.3 mm. MTM was found in 0.9% of myopic eyes and 7.3% of highly myopic eyes. In the multivariate analysis, myopic SE (p<0.001), longer AL (p<0.001), MMD (p=0.01) and epiretinal traction (p<0.001) were independent risk factors for MTM. MTM was not associated with age (p=0.38). MTM was significantly associated with poorer best-corrected visual acuity (BCVA) (p<0.01).

Conclusions: Our population-based study revealed that MTM was present in 0.9% of myopic eyes and 7.3% of highly myopic eyes. While greater myopic SE, longer AL, MMD and epiretinal traction are risk factors of MTM, age was not related to MTM. MTM has a negative effect on BCVA.
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http://dx.doi.org/10.1136/bjophthalmol-2020-316182DOI Listing
April 2021

Design, implementation, and evaluation of a nurse-led intravitreal injection programme for retinal diseases in Singapore.

Eye (Lond) 2020 11 7;34(11):2123-2130. Epub 2020 May 7.

Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.

Background: To describe the design, implementation, and evaluation of a nurse-led intravitreal injection (NL-IVT) programme in a Singapore tertiary eye hospital.

Methods: Patients requiring anti-vascular endothelial growth factor (VEGF) IVT were recruited. Implementation and evaluation were done in the Singapore National Eye Centre, a tertiary centre. To assess safety, nurse injectors recorded details of procedures performed and complications for an 8-month period from February 2019. To evaluate patient experience, we used a modified patient questionnaire and recorded both patients' waiting time and IVT procedure duration. A retrospective audit of IVTs before and after the introduction of NL-IVT was performed from January 2017 to September 2019. Cost difference between NL-IVT and standard doctor-led (DL) IVT was evaluated.

Results: A total of 8599 NL-IVTs were performed. No cases of severe complication were detected in the follow-up. A total of 135 patients who received NL-IVT and DL-IVT were surveyed. General satisfaction, interpersonal manner, financial aspect, time spent with injector, and staff competence were higher in NL-IVTs than in DL-IVTs (p < 0.05). There were no differences in terms of technical quality and communication. For 934 patients, waiting time was significantly shorter in NL-IVT (3.6 ± 10.3 min) compared with DL-IVTs (35.3 ± 32.3 min); on average, 19.7  min were saved through NL-IVT (p < 0.01). The cost difference per IVT between NL-IVT and DL-IVT is estimated at 286 SGD (163 GBP).

Conclusion: With a well-designed training programme, NL-IVT is a safe, acceptable, and cost savings procedure. With increasing demand for IVT, NL-IVT provides an alternative model of care for healthcare systems globally.
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http://dx.doi.org/10.1038/s41433-020-0920-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7784933PMC
November 2020

Six-Year Changes in Myopic Macular Degeneration in Adults of the Singapore Epidemiology of Eye Diseases Study.

Invest Ophthalmol Vis Sci 2020 04;61(4):14

.

Purpose: To examine the 6-year incidence, progression, associated risk factors, and impact of myopic macular degeneration (MMD) in a myopic population in Singapore.

Methods: We examined myopic (spherical equivalent ≤-0.5 diopters) adults (N = 2157 persons and 3661 eyes) who were phakic at baseline and participated in both baseline and 6-year follow-up visits of the Singapore Epidemiology of Eye Diseases study. Eye examinations, including visual acuity, subjective refraction and axial length (AL) measurements, were performed. MMD was graded from fundus photographs following the META-PM classification. Vision-related quality of life was assessed with Rasch-transformed scores from reading, mobility, and emotional domains of the Impact of Vision Impairment questionnaire.

Results: The 6-year eye-specific incidence of MMD among myopic eyes was 1.2% (95% CI, 0.9%-1.6%). Older age, worse spherical equivalent, and longer AL at baseline were associated with MMD incidence (all P < 0.001). The 6-year eye-specific progression of MMD in 288 eyes with baseline MMD was 17.0% (95% CI, 12.6%-21.4%). More severe MMD at baseline, worse spherical equivalent, and longer AL (all P < 0.05) were associated with MMD progression. Patients with Meta-PM categories 3 and 4 had worse best-corrected visual acuity and poorer vision-related quality of life outcomes than those without MMD (all P < 0.05).

Conclusions: Over a 6-year period, one in 80 myopic eyes developed MMD and one in six with existing MMD had MMD progression. Myopia severity and AL were strong predictors of MMD development and progression. Eyes with severe MMD were at higher risk of MMD progression than those with less severe MMD, and were associated with poorer visual acuity and vision-related quality of life.
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http://dx.doi.org/10.1167/iovs.61.4.14DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7401489PMC
April 2020

25-years Trends and Risk factors related to Surgical Outcomes of Giant Retinal Tear-Rhegmatogenous Retinal Detachments.

Sci Rep 2020 03 25;10(1):5474. Epub 2020 Mar 25.

Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore.

To describe the 25-year surgical trends, long-term outcomes and risk factors affecting the outcomes of giant retinal tear-related rhegmatogenous retinal detachments (GRT-RRD). Patients' demographics, pre-operative characteristics, risk factors, operative procedures and post-operative outcomes were collected and divided into three groups - Group A: 1991 to 2015 (overall); Group B: 1991 to 2005, and Group C: 2006 to 2015. Functional and anatomical successes were monitored over a 5-year period. Multivariate logistic regression analysis was performed to identify the risk factors related to functional and anatomical success.127 eyes of 127 patients were included in the study. At 5 year, 69.4% patients had visual acuity (VA) < logMAR 1.0 with 87.5% primary anatomical success rate. While the functional outcome remained the same between group B and C, there was an increase in the anatomical success from 89.7% to 100%, albeit not statistically significant. Patients with worse presenting VA, 150 degrees or more of giant retina tear, macula-detached status and presence of PVR were associated with VA of> logMAR 1.0 (all p < 0.05). The types of surgery (TPPV vs combined SB/TPPV), number of breaks, lens extraction and additional cryotherapy were not associated with the functional or anatomical success. In conclusion, the GRT-RRD functional and structural outcomes were comparable between 1991-2005 and 2006-2015, albeit a statistically insignificant improvement of anatomical outcome over the past 25 years. Worse presenting VA, 150 degrees or more of giant retinal tear, detached macula and presence of PVR were associated with poorer visual outcome.
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http://dx.doi.org/10.1038/s41598-020-61592-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7096512PMC
March 2020

Review: Myopia control strategies recommendations from the 2018 WHO/IAPB/BHVI Meeting on Myopia.

Br J Ophthalmol 2020 11 26;104(11):1482-1487. Epub 2020 Feb 26.

Brien Holden Vision Institute, Sydney, New South Wales, Australia.

Myopia is a major public health problem, particularly in East Asia. In this summary report, we present key findings and recommendations on strategies for myopia control discussed during the meeting jointly organised by the WHO Regional Office for the Western Pacific, the International Agency for the Prevention of Blindness and the Brien Holden Vision Institute. First, myopia prevalence was reported to be increasing, with up to 80% of junior school students with myopia in East Asia. However, common challenges in implementing myopia control strategies on a national level included lack of school screening programme, and paucity of accurate prevalence data. Second, there continues to be broad public misconception about myopia and myopia control, including lack of parental awareness and resistance to wearing spectacles. Third, best practices for myopia management were shared, and recommendations for policy implementation are presented in this review. Key recommendations from this meeting include increased public education to raise parent and teacher awareness; encouragement of increased outdoor time of 2-3 hours per day for schoolchildren-as a practical public health intervention that has been shown to potentially reduce onset and progression of myopia. Governments and non-governmental organisations are encouraged to collaborate, especially education and health ministries to develop national myopia prevention programme. Lastly, it is important to emphasise that the key recommendations, such as increasing outdoor time for schoolchildren, are specific for East Asian nations in the Western Pacific region and may not be entirely applicable for Western nations.
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http://dx.doi.org/10.1136/bjophthalmol-2019-315575DOI Listing
November 2020

A vision 'bolt-on' increases the responsiveness of EQ-5D: preliminary evidence from a study of cataract surgery.

Eur J Health Econ 2020 Jun 4;21(4):501-511. Epub 2020 Jan 4.

Saw Swee Hock School of Public Health, National University of Singapore, 12 Science Drive 2, Singapore, Singapore.

Objectives: (1) To evaluate the effect of adding a vision dimension ('bolt-on') to the 5-level EQ-5D (EQ-5D-5L) and 3-level EQ-5D (EQ-5D-3L) on their responsiveness, and (2) to compare the responsiveness of a vision 'bolt-on' EQ-5D-3L (EQ-5D-3L + V) with SF-6D and Health Utilities Index Mark 3 (HUI3) to the benefit of cataract surgery.

Methods: Sixty-three patients were assessed before and after their cataract surgery using the EQ-5D-3L, EQ-5D-5L, SF-6D, HUI3, as well as a 3-level and a 5-level vision dimension. Preference-based indices were calculated using available value sets for EQ-5D-3L, EQ-5D-3L + V, EQ-5D-5L, SF-6D, and HUI3, and non-preference-based indices were calculated using the sum-score method for EQ-5D-5L and EQ-5D-5L + V (vision bolt-on EQ-5D-5L). Responsiveness was assessed using the standardized response mean (SRM) and F-statistic.

Results: Among preference-based indices, mean changes from pre to post-surgery in EQ-5D-3L + V and EQ-5D-3L indices were 0.031 and 0.018, respectively. The mean changes for EQ-5D-5L, SF-6D and HUI3 indices were 0.020, 0.012 and 0.105, respectively. The SRM (F-statistic) for EQ-5D-3L + V and EQ-5D-3L indices were 0.458 (13.2) and 0.098 (0.6), respectively. The responsiveness of EQ-5D-3L + V was better than EQ-5D-5L, SF-6D; the responsiveness of HUI3 was better than all other measures. Using non-preference-based indices, mean change for EQ-5D-5L + V and EQ-5D-5L were 0.067 and 0.017, respectively. The corresponding SRM (F-statistic) were 0.709 (31.7) and 0.295 (5.4).

Conclusions: Preliminary evidence from our study suggests that a vision 'bolt-on' may increase the responsiveness of EQ-5D-3L and EQ-5D-5L to change in health outcomes experienced by patients undergoing cataract surgery. In absence of the preference-based vision bolt-on EQ-5D-5L index, HUI3 was the most responsive measure.
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http://dx.doi.org/10.1007/s10198-019-01156-wDOI Listing
June 2020

DIABETIC MACULAR ISCHEMIA: Correlation of Retinal Vasculature Changes by Optical Coherence Tomography Angiography and Functional Deficit.

Retina 2020 Nov;40(11):2184-2190

Singapore National Eye Centre, Singapore, Singapore.

Purpose: To examine the relationship between macular microvasculature parameters and functional changes in persons with diabetic retinopathy (DR).

Methods: Cross-sectional study of 76 eyes with varying levels of DR. Optical coherence tomography angiography (OCTA) quantified superficial and deep perifoveal vessel densities and foveal avascular zone areas. Retinal sensitivity was measured using microperimetry. Optical coherence tomography angiography parameters and retinal sensitivity were correlated.

Results: Deep perifoveal vessel density decreased with increasing severity of DR (adjusted mean 51.93 vs. 49.89 vs. 47.96, P-trend = 0.005). Superficial and deep foveal avascular zone area increased with increasing DR severity (adjusted mean: 235.0 µm vs. 303.4 µm vs. 400.9 µm, P-trend = 0.003 [superficial]; 333.1 µm vs. 513.3 µm vs. 530.2 µm, P-trend = 0.001 [deep]). Retinal sensitivity decreased with increasing DR severity (adjusted mean: 25.12 dB vs. 22.34 dB vs. 20.67 dB, P-trend = 0.003). Retinal sensitivity correlated positively with deep perifoveal vessel density (Pearson's ρ = 0.276, P = 0.020) and inversely with superficial foveal avascular zone area (Pearson's ρ = -0.333, P = 0.010).

Conclusion: Alterations in retinal microvasculature can be observed with OCTA with increasing severity of DR. These changes are correlated with reduced retinal sensitivity. Optical coherence tomography angiography is useful to detect and quantify the microvasculature properties of eyes with diabetic macular ischemia.
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http://dx.doi.org/10.1097/IAE.0000000000002721DOI Listing
November 2020

In Vitro Expansion of Keratinocytes on Human Dermal Fibroblast-Derived Matrix Retains Their Stem-Like Characteristics.

Sci Rep 2019 12 6;9(1):18561. Epub 2019 Dec 6.

School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin University, Bentley, WA, 6102, Australia.

The long-term expansion of keratinocytes under conditions that avoid xenogeneic components (i.e. animal serum- and feeder cell-free) generally causes diminished proliferation and increased terminal differentiation. Here we present a culture system free of xenogeneic components that retains the self-renewal capacity of primary human keratinocytes. In vivo the extracellular matrix (ECM) of the tissue microenvironment has a major influence on a cell's fate. We used ECM from human dermal fibroblasts, cultured under macromolecular crowding conditions to facilitate matrix deposition and organisation, in a xenogeneic-free keratinocyte expansion protocol. Phospholipase A decellularisation produced ECM whose components resembled the core matrix composition of natural dermis by proteome analyses. Keratinocytes proliferated rapidly on these matrices, retained their small size, expressed p63, lacked keratin 10 and rarely expressed keratin 16. The colony forming efficiency of these keratinocytes was enhanced over that of keratinocytes grown on collagen I, indicating that dermal fibroblast-derived matrices maintain the in vitro expansion of keratinocytes in a stem-like state. Keratinocyte sheets formed on such matrices were multi-layered with superior strength and stability compared to the single-layered sheets formed on collagen I. Thus, keratinocytes expanded using our xenogeneic-free protocol retained a stem-like state, but when triggered by confluence and calcium concentration, they stratified to produce epidermal sheets with a potential clinical use.
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http://dx.doi.org/10.1038/s41598-019-54793-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6897920PMC
December 2019

Correlation of axial length and myopic macular degeneration to levels of molecular factors in the aqueous.

Sci Rep 2019 10 31;9(1):15708. Epub 2019 Oct 31.

Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.

To elucidate the molecular processes associated with the development of myopic macular degeneration (MMD), we measured the intraocular concentrations of molecular factors in emmetropic and myopic eyes. This is a retrospective clinic-based case-control study that included eyes undergoing routine cataract surgery whereby aqueous humour samples were obtained. We measured the concentrations of pigment epithelium derived factor(PEDF), matrix metalloproteinase 2(MMP-2), tissue inhibitor of metalloproteinase(TIMP-2), vascular endothelial growth factor isoform A(VEGF-A), interleukin 8(IL-8), interleukin 6(IL-6), C-reactive protein(CRP), angiopoietin 2(Ang2), and amphiregulin. 38 eyes (axial length (AL): 22.4-32.4 mm), including 12 highly myopic (HM) eyes (AL ≥ 26.5 mm) without MMD and 12 HM eyes with MMD but without neovascularization were included. Eyes with MMD were found to have significantly lower VEGF-A levels (p = 0.007) and higher MMP-2 levels (p = 0.02) than control eyes after adjusting for age and gender. MMP-2 levels correlated positively (r = 0.58, p = 0.002), while VEGF-A levels correlated negatively with longer axial length (r = -0.75, p < 0.001). Both the concentrations of VEGF-A (P = 0.25) and MMP-2 (P = 0.69) were not significantly associated with MMD after adjusting for AL. These findings suggest that the predominant mechanism underlying the development of non-neovascular MMD may be axial elongation, driven in part by MMP-2 related mechanisms.
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http://dx.doi.org/10.1038/s41598-019-52156-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6823508PMC
October 2019

Characterisation of the inflammatory cytokine and growth factor profile in a rabbit model of proliferative vitreoretinopathy.

Sci Rep 2019 10 28;9(1):15419. Epub 2019 Oct 28.

Singapore National Eye Centre (SNEC), 11 Third Hospital Avenue, Singapore, 168751, Singapore.

To clarify the mechanisms and their temporal relationship in the development of proliferative vitreoretinopathy (PVR), we measured vitreous levels of pro-inflammatory cytokines and growth factors in a rabbit model of PVR. PVR was surgically induced in 11 rabbit eyes by vitrectomy, retinotomy, cryotherapy and injection of platelet-rich plasma at baseline. Severity of PVR was assessed on dilated fundal examination with indirect binocular ophthalmoscopy and graded based on the revised experimental PVR classification. Severe PVR was defined as stage 5 or worse. Vitreous concentrations of interleukin 6 (IL-6), interleukin 8 (IL-8), interleukin 1 beta (IL-1 β), tumor necrosis factor beta (TNF-β), granulocyte macrophage colony stimulating factor (GM-CSF), interferon gamma (IFN-γ), C reactive protein; (CRP), placental growth factor (PlGF), platelet derived growth factor BB (PDGF-BB), vascular endothelial growth factor (VEGF) and angiopoietin 2 (Ang-2) at weeks 2, 3 and 4 were compared to baseline and correlations between the cytokines with PVR severity were assessed. Four weeks after PVR induction, 5 eyes (45.5%) had developed severe PVR. IL-8 was raised at 2 weeks post PVR induction (1.46 ± 0.48 pg/ml vs 0.53 ± 0.25 pg/ml, p = 0.04) and remained significantly elevated at week 4 (2.6 ± 3.1 pg/ml, p = 0.03). CRP was significantly raised at week 4 (34.8 ± 12.0 pg/ml vs 13.0 ± 13.1 pg/ml, p < 0.001). Among the growth factors, PDGF-BB was the earliest to show significantly elevated levels, at 3 weeks (50.4 ± 19.0 pg/ml vs 6.2 ± 10.1 pg/ml) and remained elevated at week 4 (p = 0.002), while PlGF (11.2 ± 7.7 pg/ml vs 5.3 ± 3.8 pg/ml, p = 0.002) and Ang2 (13617.0 ± 8170.2 pg/ml vs 38593.8 ± 8313.4, p = 0.02) were significantly raised at week 4. IFN-γ (p = 0.03), PDGF-BB (p = 0.02) and VEGF (p = 0.02) were significantly associated with PVR severity. We demonstrated that inflammatory cytokines IL-6, -8, elevation post PVR induction is followed by elevated levels of fibroproliferative growth factors, Ang2, PlGF, VEGF and PDGF-BB in the development of PVR. These findings will guide future studies targeting appropriate therapeutic strategies for the treatment of PVR.
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http://dx.doi.org/10.1038/s41598-019-51633-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6817814PMC
October 2019

Optical coherence tomography angiography for the assessment of choroidal vasculature in high myopia.

Br J Ophthalmol 2020 07 4;104(7):917-923. Epub 2019 Oct 4.

Singapore Eye Research Institute, Singapore

Aims: To assess specific layers of the choroid in highly myopic young adults and to examine their associations with levels of myopia.

Methods: We recruited 51 young myopes (n=91 eyes) from the Singapore Cohort of Risk Factors for Myopia cohort. We performed standardised optical coherence tomography (OCT) and OCT angiography imaging and developed a novel segmentation technique assessing choroidal layers' thickness (overall choroidal thickness (CT), medium-vessel choroidal layer (MVCL) thickness, large-vessel choroidal layer (LVCL)) and vasculature (choroidal vessel density (%), choroidal branch area (CBA, %) and mean choroidal vessel width (MCVW, mm)).

Results: We found that eyes with extreme myopia (EM) had thinner vascular layers compared with high myopia (HM), that is, LVCL (36.0±1.5 vs 39.2±1.2 µm, p=0.002) and MVCL (185.5±5.7 vs 198.2±4.6 µm, p=0.014). Overall CT was thinnest in the nasal and inferior quadrants in EM (nasal: 157.1±9.6 vs 187.2±8.3 µm, p<0.001; superior: 236.6±11.1 vs 257.0±9.5 µm, p=0.02; temporal: 228.0±10.6 vs 254.3±8.8 µm, p=0.012; and inferior quadrant: 198.7±10.0 vs 239.8±8.3 µm, p=<0.001) when compared with HM. We also observed significantly more vessel branching in eyes with EM as compared with eyes with HM (CBA, 10.2%±0.7% vs 9.95%±0.8%, p=0.018).

Conclusions: The novel segmentation technique and introduced choroidal parameters may serve as new biomarkers to study disease conditions in myopia.
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http://dx.doi.org/10.1136/bjophthalmol-2019-314769DOI Listing
July 2020

Genetic variants linked to myopic macular degeneration in persons with high myopia: CREAM Consortium.

PLoS One 2019 15;14(8):e0220143. Epub 2019 Aug 15.

Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.

Purpose: To evaluate the roles of known myopia-associated genetic variants for development of myopic macular degeneration (MMD) in individuals with high myopia (HM), using case-control studies from the Consortium of Refractive Error and Myopia (CREAM).

Methods: A candidate gene approach tested 50 myopia-associated loci for association with HM and MMD, using meta-analyses of case-control studies comprising subjects of European and Asian ancestry aged 30 to 80 years from 10 studies. Fifty loci with the strongest associations with myopia were chosen from a previous published GWAS study. Highly myopic (spherical equivalent [SE] ≤ -5.0 diopters [D]) cases with MMD (N = 348), and two sets of controls were enrolled: (1) the first set included 16,275 emmetropes (SE ≤ -0.5 D); and (2) second set included 898 highly myopic subjects (SE ≤ -5.0 D) without MMD. MMD was classified based on the International photographic classification for pathologic myopia (META-PM).

Results: In the first analysis, comprising highly myopic cases with MMD (N = 348) versus emmetropic controls without MMD (N = 16,275), two SNPs were significantly associated with high myopia in adults with HM and MMD: (1) rs10824518 (P = 6.20E-07) in KCNMA1, which is highly expressed in human retinal and scleral tissues; and (2) rs524952 (P = 2.32E-16) near GJD2. In the second analysis, comprising highly myopic cases with MMD (N = 348) versus highly myopic controls without MMD (N = 898), none of the SNPs studied reached Bonferroni-corrected significance.

Conclusions: Of the 50 myopia-associated loci, we did not find any variant specifically associated with MMD, but the KCNMA1 and GJD2 loci were significantly associated with HM in highly myopic subjects with MMD, compared to emmetropes.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0220143PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6695159PMC
March 2020

Global Assessment of Retinal Arteriolar, Venular and Capillary Microcirculations Using Fundus Photographs and Optical Coherence Tomography Angiography in Diabetic Retinopathy.

Sci Rep 2019 08 13;9(1):11751. Epub 2019 Aug 13.

Singapore Eye Research Institute, Singapore, Singapore National Eye Centre, Singapore, Singapore.

Retinal arterioles, venules and capillaries are differentially affected in diabetes, and studying vascular alterations may provide information on pathogenesis of diabetic retinopathy (DR). We conducted a cross-sectional study on 49 diabetic patients, who underwent fundus photography and optical coherence tomographic angiography (OCT-A). Fundus photographs were analysed using semi-automated software for arteriolar and venular parameters, including central retinal arteriolar equivalent (CRAE), central retinal venular equivalent (CRVE) and fractal dimension (FD). Capillary parameters were measured using OCT-A, including capillary density index (CDI) and capillary FD of superficial (SVP) and deep (DVP) vascular plexuses. Severe DR was defined as severe non-proliferative DR and proliferative DR. We found that eyes with severe DR had narrower CRAE and sparser SVP CDI than eyes without. In logistic regression analysis, capillary parameters were more associated with severe DR than arteriolar or venular parameters. However, combining arteriolar, venular and capillary parameters provided the strongest association with severe DR. In linear regression analysis, eyes with poorer visual acuity had lower CRAE and FD of arterioles, venules, and DVP capillaries. We concluded that the retinal microvasculature is globally affected in severe DR, reflecting widespread microvascular impairment in perfusion. Arteriolar, venular and capillary parameters provide complementary information in assessment of DR.
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http://dx.doi.org/10.1038/s41598-019-47770-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6692394PMC
August 2019

Posterior segment drug delivery for the treatment of exudative age-related macular degeneration and diabetic macular oedema.

Br J Ophthalmol 2019 10 30;103(10):1356-1360. Epub 2019 Apr 30.

Duke-NUS Graduate Medical School, Singapore, Singapore

Inhibitors of vascular endothelial growth factors are used to treat a myriad of retinal conditions, including exudative age-related macular degeneration (AMD), diabetic macular oedema (DME) and diabetic retinopathy. Although effective, long-term efficacy is limited by the need for frequent and invasive intravitreal injections. The quest for sustained action therapeutics that can be delivered to target tissue in the least invasive manner is an arduous endeavour that has ended in premature failure for several technologies in Phase II or III trials. Nevertheless, there have been promising preclinical studies, and more are on the horizon: port delivery systems for the treatment of exudative AMD have entered Phase III trials and a wide array of preclinical studies have demonstrated the potential for nanoparticles, such as liposomes, dendrimers and cell penetrating peptides to deliver therapeutics into the posterior segment via minimally invasive routes. In this review, we discuss the challenges posed by ocular barriers for drug penetration and present the recent advancements of the most pertinent drug delivery platforms with a focus on the treatment of exudative AMD and DME.
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http://dx.doi.org/10.1136/bjophthalmol-2018-313462DOI Listing
October 2019

Imaging in myopia: potential biomarkers, current challenges and future developments.

Br J Ophthalmol 2019 06 12;103(6):855-862. Epub 2019 Jan 12.

Singapore National Eye Centre, Singapore, Singapore.

Myopia is rapidly increasing in Asia and around the world, while it is recognised that complications from high myopia may cause significant visual impairment. Thus, imaging the myopic eye is important for the diagnosis of sight-threatening complications, monitoring of disease progression and evaluation of treatments. For example, recent advances in high-resolution imaging using optical coherence tomography may delineate early myopic macula pathology, optical coherence tomography angiography may aid early choroidal neovascularisation detection, while multimodal imaging is important for monitoring treatment response. However, imaging the eye with high myopia accurately has its challenges and limitations, which are important for clinicians to understand in order to choose the best imaging modality and interpret the images accurately. In this review, we present the current imaging modalities available from the anterior to posterior segment of the myopic eye, including the optic nerve. We summarise the clinical indications, image interpretation and future developments that may overcome current technological limitations. We also discuss potential biomarkers for myopic progression or development of complications, including basement membrane defects, and choroidal atrophy or choroidal thickness measurements. Finally, we present future developments in the field of myopia imaging, such as photoacoustic imaging and corneal or scleral biomechanics, which may lead to innovative treatment modalities for myopia.
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http://dx.doi.org/10.1136/bjophthalmol-2018-312866DOI Listing
June 2019

EQ-5D-5L is More Responsive than EQ-5D-3L to Treatment Benefit of Cataract Surgery.

Patient 2019 08;12(4):383-392

Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore.

Background: It is not clear whether 5-level EQ-5D (EQ-5D-5L) utilities based on recently developed value sets are more responsive than 3-level EQ-5D (EQ-5D-3L) utilities.

Objectives: The study aims were to compare (1) the responsiveness of EQ-5D-5L and EQ-5D-3L utilities and (2) the responsiveness of these utilities with the Short Form-6 Dimension (SF-6D) and Health Utilities Index Mark 3 (HUI3) utilities to the treatment benefit of cataract surgery.

Methods: A total of 148 patients were interviewed before and after their cataract surgery using EQ-5D-3L, EQ-5D-5L, SF-6D, and HUI3. Responsiveness was assessed for all measures using the mean change (post-treatment-pre-treatment), standardized effect size (SES), standardized response mean (SRM), and F-statistic.

Results: Using the Singapore value sets, mean change for EQ-5D-3L and EQ-5D-5L utilities was 0.016 and 0.028, SES was 0.097 and 0.199; SRM was 0.091 and 0.196; and F-statistic was 1.2 and 5.7, respectively. Similar trends were observed using the UK/England EQ-5D value sets, although the magnitude was slightly smaller. The mean change, SES, SRM and F-statistics for SF-6D (UK value set) were 0.020, 0.234, 0.249, and 9.2, respectively. The values of mean change, SES, SRM and F-statistics for HUI3 (Canada value set) were 0.080, 0.472, 0.474, and 33.3, respectively.

Conclusions: The EQ-5D-5L utilities tend to be more responsive than the EQ-5D-3L utilities to treatment benefits of cataract surgery. The HUI3 utilities are more responsive than both the EQ-5D-5L and SF-6D, and SF-6D utilities may be slightly more responsive than the EQ-5D-5L for assessing patients undergoing cataract surgery.
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http://dx.doi.org/10.1007/s40271-018-00354-7DOI Listing
August 2019