Kelvin Yi Chong Teo

Dr. Kelvin Yi Chong Teo


Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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18 November 2019 in Eye and Vision
Verified
Journal Article
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KTKai Yuan Tey
Kai Yuan Tey
KTKelvin Yi Chong Teo
Kelvin Yi Chong Teo
ATAnna C. S. Tan
Anna C. S. Tan
KDKavya Devarajan
Kavya Devarajan
BTBingyao Tan
Bingyao Tan
MAMarcus Ang
Marcus Ang
Background: Diabetic retinopathy (DR) is a leading cause of vision loss in adults. Currently, the standard imaging technique to monitor and prognosticate DR and diabetic maculopathy is dye-based angiography. With the introduction of optical coherence tomography angiography (OCTA), it may serve as a potential rapid, non-invasive imaging modality as an adjunct.Main text: Recent studies on the role of OCTA in DR include the use of vascular parameters e.g., vessel density, intercapillary spacing, vessel diameter index, length of vessels based on skeletonised OCTA, the total length of vessels, vascular architecture and area of the foveal avascular zone. These quantitative measures may be able to detect changes with the severity and progress of DR for clinical research. OCTA may also serve as a non-invasive imaging method to detect diabetic macula ischemia, which may help predict visual prognosis. However, there are many limitations of OCTA in DR, such as difficulty in segmentation between superficial and deep capillary plexus; and its use in diabetic macula edema where the presence of cystic spaces may affect image results. Future applications of OCTA in the anterior segment include detection of anterior segment ischemia and iris neovascularisation associated with proliferative DR and risk of neovascular glaucoma.Conclusion: OCTA may potentially serve as a useful non-invasive imaging tool in the diagnosis and monitoring of diabetic retinopathy and maculopathy in the future. Future studies may demonstrate how quantitative OCTA measures may have a role in detecting early retinal changes in patients with diabetes.

24 September 2022 in American Journal of Ophthalmology
Verified
Journal Article
Closed access
KCKai Xiong Cheong
Kai Xiong Cheong
CCChui Ming Gemmy Cheung
Chui Ming Gemmy Cheung
KTKelvin Yi Chong Teo
Kelvin Yi Chong Teo

7 April 2023 in American Journal of Ophthalmology
Verified
Journal Article
Open access
FRFrancesco Romano
Francesco Romano
ECElisa Cozzi
Elisa Cozzi
MAMatteo Airaldi
Matteo Airaldi
MNMarco Nassisi
Marco Nassisi
FVFrancesco Viola
Francesco Viola
AIAlessandro Invernizzi
Alessandro Invernizzi
To report the incidence and risk factors for fibrosis at 10 years in a large cohort of persons with neovascular age-related macular degeneration (nAMD). Retrospective, multicenter, cohort study. We included 225 naive nAMD eyes that underwent intravitreal anti-vascular endothelial growth factor treatment over 10 years of follow-up at two Italian referral centers. Demographic and clinical data were reviewed at baseline and on an annual basis. Onset of fibrosis was defined by clinically assessing photographs, fundus descriptions, or fluorescein angiograms. Optical coherence tomography (OCT) scans of fibrosis were inspected by an external reading center and graded as subretinal pigment epithelium (RPE), mixed, or subretinal. The mean age at baseline was of 72.1 ± 6.9 years. The incidence rate of fibrosis was estimated to be 8.9 per 100 person-years, with a cumulative incidence of 62.7% at 10 years. Fibrotic lesions were sub-RPE in 46.1%, mixed in 29.8%, and subretinal in 22.7%. Independent factors associated with fibrosis included the following: larger central subfield thickness variation (P < .001), submacular hemorrhages (P = .008), higher number of injections (P = .01), and worse baseline visual acuity (VA) (P = .03). Type 2 macular neovascularization was significantly associated with mixed and subretinal fibrosis. VA significantly declined over 10 years (-16.4 Early Treatment Diabetic Retinopathy Study [ETDRS] letters), particularly in eyes with mixed and subretinal fibrosis (P < .001). We identified a 62.7% cumulative incidence of fibrosis in a large nAMD cohort at 10 years. Fibrosis was more common with frequent reactivations and lower baseline VA; its onset had a significant impact on final VA. This supports the hypothesis that nAMD patients should be promptly treated with proactive regimens.

7 February 2022 in Clinical & Experimental Ophthalmology
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Journal Article
Open access
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Himal KandelHimal Kandel
Himal Kandel
VNVuong Nguyen
Vuong Nguyen
SPStefano Piermarocchi
Stefano Piermarocchi
LCLala Ceklic
Lala Ceklic
KTKelvin Yi Chong Teo
Kelvin Yi Chong Teo
SWStephanie Watson
Stephanie Watson
Background: The objectives of this study were to evaluate the quality‐of‐life (QoL) impact of eye diseases (keratoconus; neovascular age‐related macular degeneration, AMD; retinal vein occlusion, RVO; and diabetic macular edema, DME) using the Impact of Vision Impairment (IVI) questionnaire, and to determine the relationship between the IVI scores and visual acuity.Methods: This cross‐sectional, multicentre, real‐world study utilised the prospective, web‐based Save Sight Registries. The IVI was completed by 1557 patients: 307 with keratoconus, 1049 with AMD, 148 with RVO and 53 with DME. Statistical analysis included Rasch analysis, Welcht‐test, one‐way ANOVA, Tukey's test, Pearson correlation, and multiple regression.Results: The IVI scales (Overall; Visual Function, VF; Emotional, EM) had robust psychometric properties. The keratoconus patients had the worst Overall (adjusted mean: 48.2 vs. DME 58.8, RVO 64.6, AMD 67.6 units), VF (47.7 vs. DME 59.4, RVO 65.9, AMD 68.9 units) and EM (50.8 vs. DME 63.1, RVO 69.2, AMD 71.8 units) scores (allp < 0.05).The IVI scales scores weakly correlated with better and worse eye visual acuity (Pearson'sr0.24–0.39, allp < 0.05). The correlations were similar in the better eye (Overall 0.35, VF 0.39, EM 0.24) and the worse eye (Overall 0.31, VF 0.33, EM 0.25) visual acuity. Correlations with visual acuity were stronger for VF than for the EM scores.Conclusions: The IVI was a psychometrically robust QoL questionnaire. Keratoconus patients had worse IVI scores than patients with retinal diseases. The low strength of correlations between visual acuity and QoL scores, although statistically significant, suggested that a complex relationship exists.

17 February 2020 in Retina
Verified
Journal Article
Closed access
KTKelvin Yi Chong Teo
Kelvin Yi Chong Teo
AJAaron W. Joe
Aaron W. Joe
VNVuong Nguyen
Vuong Nguyen
AIAlessandro Invernizzi
Alessandro Invernizzi
JAJennifer J. Mbbs Arnold
Jennifer J. Mbbs Arnold
MGMark Gillies
Mark Gillies
Purpose: To assess the prevalence and incidence of and risk factors for subretinal fibrosis (SRFi) in eyes with neovascular age-related macular degeneration (nAMD) that underwent vascular endothelial growth factor inhibitor treatment for up to 10 years. Methods: A cross-sectional and longitudinal analysis was performed on data from a neovascular age-related macular degeneration registry. The presence and location of SRFi were graded by the treating practitioner. Visual acuity, lesion characteristics (type, morphology, and activity), and treatment administered at each visit was recorded. Results: The prevalence of SRFi in 2,914 eyes rose from 20.4% at year interval 0-1 to 40.7% at year interval 9 to 10. The incidence in 1,950 eyes was 14.3% at baseline and 26.3% at 24 months. Independent characteristics associated with SRFi included poorer baseline vision (adjusted odds ratio 5.33 [95% confidence interval 4.66–7.61] for visual acuity ≤35 letters vs. visual acuity ≥70 letters, P < 0.01), baseline lesion size (adjusted odds ratio 1.08 [95% confidence interval 1.08–1.14] per 1000 µm, P = 0.03), lesion type (adjusted odds ratio 1.42 [95% confidence interval 1.17–1.72] for predominantly classic vs. occult lesions, P = 0.02), and proportion of active visits (adjusted odds ratio 1.58 [95% confidence interval 1.25–2.01] for the group with the highest level of activity vs. the lowest level of activity, P < 0.01). Conclusion: Subretinal fibrosis was found in 40% of eyes after 10 years of treatment. High rates of lesion activity, predominantly classic lesions, poor baseline vision, and larger lesion size seem to be independent risk factors for SRFi.

14 July 2021 in Eye
Verified
Journal Article
Open access
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BFBeau J. Fenner
Beau J. Fenner
CCChui Ming Gemmy Cheung
Chui Ming Gemmy Cheung
SSShaun S. Sim
Shaun S. Sim
WLWon Ki Lee
Won Ki Lee
GSGiovanni Staurenghi
Giovanni Staurenghi
KTKelvin Yi Chong Teo
Kelvin Yi Chong Teo
Polypoidal choroidal vasculopathy (PCV) is a subtype of neovascular AMD (nAMD) that accounts for a significant proportion of nAMD cases worldwide, and particularly in Asia. Contemporary PCV treatment strategies have closely followed those used in typical nAMD, though there are significant gaps in knowledge on PCV management and it remains unclear if these strategies are appropriate. Current clinical trial data suggest intravitreal anti-vascular endothelial growth factor (VEGF) therapy alone or in combination with photodynamic therapy is effective in managing haemorrhage and exudation in PCV, although the optimal treatment interval, including as-needed and treat-and-extend approaches, is unclear. Newer imaging modalities, including OCT angiography and high-resolution spectral domain OCT have enabled characterisation of unique PCV biomarkers that may provide guidance on how and when treatment and re-treatment should be initiated. Treatment burden for PCV is a major focus of future therapeutic research and several newly developed anti-VEGF agents, including brolucizumab, faricimab, and new modes of drug delivery like the port delivery system, offer hope for dramatically reduced treatment burden for PCV patients. Beyond anti-VEGF therapy, recent developments in our understanding of PCV pathophysiology, in particular the role of choroidal anatomy and lipid mediators in PCV pathogenesis, offer new treatment avenues that may become clinically relevant in the future. This article explores the current management of PCV and more recent approaches to PCV treatment based on an improved understanding of this unique disease process.