1.Compact Fundus Imaging System Using Shack-Hartmann Wavefront Sensing for High-speed Auto-focus
Zhe-Kai LIN ; Long CHEN ; Geng-Yong ZHENG ; Jin-Tian HUANG ; Jia-Xin DONG ; Shang-Pan YANG ; Wen-Zheng DING ; Ding-An HAN ; Xue-Hua WANG ; Ya-Guang ZENG
Progress in Biochemistry and Biophysics 2026;53(4):1076-1086
ObjectiveThe widespread adoption of portable fundus cameras for primary care and community screening is hindered by limitations in current autofocus(AF) technologies. Image-based methods relying on sharpness evaluation require iterative searches, resulting in slow convergence, while projection-based techniques are susceptible to optical artifacts and calibration errors. To address these challenges, this study introduces a novel AF system based on direct wavefront sensing, designed to deliver simultaneous high speed, high precision, and operational robustness within the compact form factor essential for portable ophthalmic devices. MethodsOur approach fundamentally reimagines the AF process by directly measuring the ocular wavefront aberration. We developed a custom portable fundus camera integrating a miniaturized Shack-Hartmann wavefront sensor (SHWS) into the optical path. An 850 nm laser diode projects a point source onto the retina via oblique illumination to minimize corneal reflections. Light scattered from this spot carries the eye’s refractive error through the imaging optics and is directed to the SHWS, positioned at a plane optically conjugate to the primary color CMOS imaging sensor. A microlens array within the SHWS samples the incident wavefront, generating a pattern of focal spots on a CCD. Real-time centroid analysis of these spots provides a map of local wavefront slopes. These measurements are processed through a singular value decomposition (SVD) algorithm to fit a Zernike polynomial basis set, enabling real-time reconstruction of the wavefront phase. The defocus component (S) is extracted from the second-order Zernike coefficients, providing a direct, quantitative measure of the refractive error in diopters. This value serves as a precise error signal in a closed-loop control system, which commands a voice-coil actuated focusing lens to its null position in a single, deterministic step, eliminating the need for iterative search algorithms. ResultsComprehensive evaluation demonstrated the system’s high performance. Testing on a calibrated model eye (OEMI-7) established a highly linear relationship between the computed defocus S and the focusing lens position across a ±20 Diopter (D) compensation range, achievable within a 5 mm mechanical travel. The system achieved a focusing precision of 0.08 D, corresponding to an 18-fold improvement over a conventional projection spot-size method tested under identical conditions. The total focus acquisition time, encompassing wavefront measurement, computation, and lens actuation, averaged under 0.5 s. Clinical validation with 25 human volunteers (50 eyes, refractive range -15 D to +10 D) confirmed practical efficacy. The wavefront-sensing AF succeeded in 92% of attempts with a mean time of 0.5 s, substantially outperforming a projection-based benchmark which achieved only a 32% success rate with an average time of 4.25 s. The system provided instantaneous directional guidance and maintained stability during minor ocular movements. Objective assessment of image quality, via amplitude contrast of retinal vasculature, showed consistent and significant enhancement following AF correction across the entire tested diopter range. ConclusionThis work successfully implements and validates a direct wavefront-sensing autofocus paradigm for portable fundus cameras. By directly quantifying and compensating for the optical defocus aberration, this method bypasses the fundamental limitations of image-processing and projection-based techniques, enabling rapid, precise, and deterministic diopter compensation. The developed system delivers an exceptional combination of a wide operational range (±20 D), high accuracy (0.08 D), fast convergence (0.5 s), and a compact physical footprint. This technology provides a practical and high-performance focusing solution capable of enhancing the reliability, throughput, and diagnostic utility of portable retinal imaging in large-scale screening applications. Future efforts will be directed towards system cost optimization and performance adaptation for diverse ocular conditions.
2.A unified framework for postoperative complications after gastrectomy for gastric cancer: insights from the Korean Quality Improvement Platform in Surgery program
Jeong Ho SONG ; Chang Seok KO ; Han Hong LEE ; Hong Man YOON ; Hyoung-Il KIM ; In Gyu KWON ; Ji Yeon PARK ; Ji Yeong AN ; Jong Won KIM ; Mi Ran JUNG ; Sang-Il LEE ; Seong Ho KONG ; Sun-Hwi HWANG ; Yun-Suhk SUH ; Sang-Yong SON ; Sang-Uk HAN
Annals of Surgical Treatment and Research 2026;110(5):290-298
Purpose:
Postoperative complications following gastric cancer surgery significantly impact patient outcomes, yet standardized definitions for these events have not been consistently applied across institutions in Korea. This study aimed to develop a consensus-based, standardized complication classification system specific to gastrectomy for gastric cancer as part of the Korean Quality Improvement Platform in Surgery (K-QIPS) initiative.
Methods:
As part of K-QIPS, a dedicated task force team (TFT) was formed with surgical experts from fourteen high-volume hospitals across Korea. The TFT conducted ten formal meetings to review existing literature and international guidelines, and incorporated findings from randomized controlled trials. The final complication list was developed through expert consensus and structured into a standardized framework. A Data Entry Manual was created to support consistent data collection by surgical clinical reviewers.
Results:
The TFT defined specific postoperative complications following gastrectomy for gastric cancer, including anastomotic leakage, duodenal stump leakage, pancreatic fistula, intra-abdominal and luminal bleeding, delayed gastric emptying, and internal hernia. Notably, internal hernia was described in standardized form for the first time. General complications were developed first and overlapped in part with the gastric cancer-specific list. The task force also produced a Data Entry Manual that provides practical instructions to ensure consistency and accuracy in complication reporting.
Conclusion
This nationwide consensus initiative established the first standardized complication classification system for gastric cancer surgery in Korea. The proposed definitions and data entry system are expected to improve complication reporting, enable multicenter research, support surgical quality benchmarking, and ultimately enhance patient outcomes.
3.Identification and Potential Clinical Utility of Common Genetic Variants in Gestational Diabetes among Chinese Pregnant Women
Claudia Ha-ting TAM ; Ying WANG ; Chi Chiu WANG ; Lai Yuk YUEN ; Cadmon King-poo LIM ; Junhong LENG ; Ling WU ; Alex Chi-wai NG ; Yong HOU ; Kit Ying TSOI ; Hui WANG ; Risa OZAKI ; Albert Martin LI ; Qingqing WANG ; Juliana Chung-ngor CHAN ; Yan Chou YE ; Wing Hung TAM ; Xilin YANG ; Ronald Ching-wan MA
Diabetes & Metabolism Journal 2025;49(1):128-143
Background:
The genetic basis for hyperglycaemia in pregnancy remain unclear. This study aimed to uncover the genetic determinants of gestational diabetes mellitus (GDM) and investigate their applications.
Methods:
We performed a meta-analysis of genome-wide association studies (GWAS) for GDM in Chinese women (464 cases and 1,217 controls), followed by de novo replications in an independent Chinese cohort (564 cases and 572 controls) and in silico replication in European (12,332 cases and 131,109 controls) and multi-ethnic populations (5,485 cases and 347,856 controls). A polygenic risk score (PRS) was derived based on the identified variants.
Results:
Using the genome-wide scan and candidate gene approaches, we identified four susceptibility loci for GDM. These included three previously reported loci for GDM and type 2 diabetes mellitus (T2DM) at MTNR1B (rs7945617, odds ratio [OR], 1.64; 95% confidence interval [CI],1.38 to 1.96]), CDKAL1 (rs7754840, OR, 1.33; 95% CI, 1.13 to 1.58), and INS-IGF2-KCNQ1 (rs2237897, OR, 1.48; 95% CI, 1.23 to 1.79), as well as a novel genome-wide significant locus near TBR1-SLC4A10 (rs117781972, OR, 2.05; 95% CI, 1.61 to 2.62; Pmeta=7.6×10-9), which has not been previously reported in GWAS for T2DM or glycaemic traits. Moreover, we found that women with a high PRS (top quintile) had over threefold (95% CI, 2.30 to 4.09; Pmeta=3.1×10-14) and 71% (95% CI, 1.08 to 2.71; P=0.0220) higher risk for GDM and abnormal glucose tolerance post-pregnancy, respectively, compared to other individuals.
Conclusion
Our results indicate that the genetic architecture of glucose metabolism exhibits both similarities and differences between the pregnant and non-pregnant states. Integrating genetic information can facilitate identification of pregnant women at a higher risk of developing GDM or later diabetes.
4.Identification and Potential Clinical Utility of Common Genetic Variants in Gestational Diabetes among Chinese Pregnant Women
Claudia Ha-ting TAM ; Ying WANG ; Chi Chiu WANG ; Lai Yuk YUEN ; Cadmon King-poo LIM ; Junhong LENG ; Ling WU ; Alex Chi-wai NG ; Yong HOU ; Kit Ying TSOI ; Hui WANG ; Risa OZAKI ; Albert Martin LI ; Qingqing WANG ; Juliana Chung-ngor CHAN ; Yan Chou YE ; Wing Hung TAM ; Xilin YANG ; Ronald Ching-wan MA
Diabetes & Metabolism Journal 2025;49(1):128-143
Background:
The genetic basis for hyperglycaemia in pregnancy remain unclear. This study aimed to uncover the genetic determinants of gestational diabetes mellitus (GDM) and investigate their applications.
Methods:
We performed a meta-analysis of genome-wide association studies (GWAS) for GDM in Chinese women (464 cases and 1,217 controls), followed by de novo replications in an independent Chinese cohort (564 cases and 572 controls) and in silico replication in European (12,332 cases and 131,109 controls) and multi-ethnic populations (5,485 cases and 347,856 controls). A polygenic risk score (PRS) was derived based on the identified variants.
Results:
Using the genome-wide scan and candidate gene approaches, we identified four susceptibility loci for GDM. These included three previously reported loci for GDM and type 2 diabetes mellitus (T2DM) at MTNR1B (rs7945617, odds ratio [OR], 1.64; 95% confidence interval [CI],1.38 to 1.96]), CDKAL1 (rs7754840, OR, 1.33; 95% CI, 1.13 to 1.58), and INS-IGF2-KCNQ1 (rs2237897, OR, 1.48; 95% CI, 1.23 to 1.79), as well as a novel genome-wide significant locus near TBR1-SLC4A10 (rs117781972, OR, 2.05; 95% CI, 1.61 to 2.62; Pmeta=7.6×10-9), which has not been previously reported in GWAS for T2DM or glycaemic traits. Moreover, we found that women with a high PRS (top quintile) had over threefold (95% CI, 2.30 to 4.09; Pmeta=3.1×10-14) and 71% (95% CI, 1.08 to 2.71; P=0.0220) higher risk for GDM and abnormal glucose tolerance post-pregnancy, respectively, compared to other individuals.
Conclusion
Our results indicate that the genetic architecture of glucose metabolism exhibits both similarities and differences between the pregnant and non-pregnant states. Integrating genetic information can facilitate identification of pregnant women at a higher risk of developing GDM or later diabetes.
5.Variations in management strategies for stable coronary artery disease in the Asia-Pacific region: Insights from a multinational survey.
Lucky CUENZA ; Satoshi HONDA ; Khi Yung FONG ; Mitsuaki SAWANO ; F Aaysha CADER ; Purich SURUNCHUPAKORN ; Wishnu Aditya WIDODO ; Mayank DALAKOTI ; Jeehoon KANG ; Misato CHIMURA ; Mohammed AL-OMARY ; Zhen-Vin LEE ; Novi Yanti SARI ; Thanawat SUESAT ; Tanveer AHMAD ; Jose Donato MAGNO ; Chen Ting TAN ; Badai Bhatara TIKSNADI ; Uditha HEWARATHNA ; Faisal HABIB ; Derek Pok Him LEE ; Jonathan YAP
Annals of the Academy of Medicine, Singapore 2025;54(5):283-295
INTRODUCTION:
Randomised controlled trials (RCTs) have informed guideline recommendations for the management of stable coronary artery disease (CAD). However, the real-world impact of contemporary guidelines and trials on practising physicians in the Asia-Pacific region remains uncertain. We aimed to evaluate the knowledge, attitudes and practices among cardiovascular physicians in the region regarding stable CAD management.
METHOD:
An anonymised cross-sectional electronic survey was administered to cardiovascular practitioners from the Asia Pacific, assessing 3 domains: 1) baseline knowledge on recent trials and society guideline, 2) attitudes towards stable CAD, and 3) case scenarios reflecting management preferences. Correlations among knowledge, attitudes and practice scores were assessed between physicians from developed and developing countries using Pearson correlation.
RESULTS:
Overall, 713 respondents from 21 countries completed the survey. The mean knowledge score was 2.90±1.18 (out of 4), with 37.3% of respondents answering all questions correctly, while 74.6% noted that guidelines have significant impact on their practice. Despite guidelines recommending optimal medical therapy, majority chose revascularisation (range 53.4- 90.6%) as the preferred strategy for the case scenarios. Practitioners from developed regions had higher knowledge scores and lower attitude scores compared to developing regions, while practice scores were similar in both groups. Weakly positive correlations were noted between knowledge, attitude and practice scores.
CONCLUSION
Variations exist in knowledge and attitudes towards guideline recommendations and correspondingly actual clinical practice in the Asia Pacific, with most practitioners choosing an upfront invasive strategy for the treatment of stable CAD. These differences reflect real-world disparities in guideline interpretation and clinical adoption.
Humans
;
Coronary Artery Disease/therapy*
;
Cross-Sectional Studies
;
Practice Patterns, Physicians'/statistics & numerical data*
;
Asia
;
Health Knowledge, Attitudes, Practice
;
Surveys and Questionnaires
;
Male
;
Practice Guidelines as Topic
;
Female
;
Attitude of Health Personnel
;
Middle Aged
;
Developing Countries
6.Prognostic factors and outcomes of extremity necrotising fasciitis in Singapore.
Shaun Kai Kiat CHUA ; Noah Tian Run LIM ; Anna Hien Anh TRAN ; Liang SHEN ; Choon Chiet HONG ; Joel Yong Hao TAN ; Mark Edward PUHAINDRAN ; Jonathan Jiong Hao TAN
Annals of the Academy of Medicine, Singapore 2025;54(10):679-681
7.Performance evaluation of a wearable steady-state visual evoked potential based brain-computer interface in real-life scenario.
Xiaodong LI ; Xiang CAO ; Junlin WANG ; Weijie ZHU ; Yong HUANG ; Feng WAN ; Yong HU
Journal of Biomedical Engineering 2025;42(3):464-472
Brain-computer interface (BCI) has high application value in the field of healthcare. However, in practical clinical applications, convenience and system performance should be considered in the use of BCI. Wearable BCIs are generally with high convenience, but their performance in real-life scenario needs to be evaluated. This study proposed a wearable steady-state visual evoked potential (SSVEP)-based BCI system equipped with a small-sized electroencephalogram (EEG) collector and a high-performance training-free decoding algorithm. Ten healthy subjects participated in the test of BCI system under simplified experimental preparation. The results showed that the average classification accuracy of this BCI was 94.10% for 40 targets, and there was no significant difference compared to the dataset collected under the laboratory condition. The system achieved a maximum information transfer rate (ITR) of 115.25 bit/min with 8-channel signal and 98.49 bit/min with 4-channel signal, indicating that the 4-channel solution can be used as an option for the few-channel BCI. Overall, this wearable SSVEP-BCI can achieve good performance in real-life scenario, which helps to promote BCI technology in clinical practice.
Brain-Computer Interfaces
;
Humans
;
Evoked Potentials, Visual/physiology*
;
Electroencephalography
;
Wearable Electronic Devices
;
Algorithms
;
Signal Processing, Computer-Assisted
;
Adult
;
Male
8.Identification and Potential Clinical Utility of Common Genetic Variants in Gestational Diabetes among Chinese Pregnant Women
Claudia Ha-ting TAM ; Ying WANG ; Chi Chiu WANG ; Lai Yuk YUEN ; Cadmon King-poo LIM ; Junhong LENG ; Ling WU ; Alex Chi-wai NG ; Yong HOU ; Kit Ying TSOI ; Hui WANG ; Risa OZAKI ; Albert Martin LI ; Qingqing WANG ; Juliana Chung-ngor CHAN ; Yan Chou YE ; Wing Hung TAM ; Xilin YANG ; Ronald Ching-wan MA
Diabetes & Metabolism Journal 2025;49(1):128-143
Background:
The genetic basis for hyperglycaemia in pregnancy remain unclear. This study aimed to uncover the genetic determinants of gestational diabetes mellitus (GDM) and investigate their applications.
Methods:
We performed a meta-analysis of genome-wide association studies (GWAS) for GDM in Chinese women (464 cases and 1,217 controls), followed by de novo replications in an independent Chinese cohort (564 cases and 572 controls) and in silico replication in European (12,332 cases and 131,109 controls) and multi-ethnic populations (5,485 cases and 347,856 controls). A polygenic risk score (PRS) was derived based on the identified variants.
Results:
Using the genome-wide scan and candidate gene approaches, we identified four susceptibility loci for GDM. These included three previously reported loci for GDM and type 2 diabetes mellitus (T2DM) at MTNR1B (rs7945617, odds ratio [OR], 1.64; 95% confidence interval [CI],1.38 to 1.96]), CDKAL1 (rs7754840, OR, 1.33; 95% CI, 1.13 to 1.58), and INS-IGF2-KCNQ1 (rs2237897, OR, 1.48; 95% CI, 1.23 to 1.79), as well as a novel genome-wide significant locus near TBR1-SLC4A10 (rs117781972, OR, 2.05; 95% CI, 1.61 to 2.62; Pmeta=7.6×10-9), which has not been previously reported in GWAS for T2DM or glycaemic traits. Moreover, we found that women with a high PRS (top quintile) had over threefold (95% CI, 2.30 to 4.09; Pmeta=3.1×10-14) and 71% (95% CI, 1.08 to 2.71; P=0.0220) higher risk for GDM and abnormal glucose tolerance post-pregnancy, respectively, compared to other individuals.
Conclusion
Our results indicate that the genetic architecture of glucose metabolism exhibits both similarities and differences between the pregnant and non-pregnant states. Integrating genetic information can facilitate identification of pregnant women at a higher risk of developing GDM or later diabetes.
9.Identification and Potential Clinical Utility of Common Genetic Variants in Gestational Diabetes among Chinese Pregnant Women
Claudia Ha-ting TAM ; Ying WANG ; Chi Chiu WANG ; Lai Yuk YUEN ; Cadmon King-poo LIM ; Junhong LENG ; Ling WU ; Alex Chi-wai NG ; Yong HOU ; Kit Ying TSOI ; Hui WANG ; Risa OZAKI ; Albert Martin LI ; Qingqing WANG ; Juliana Chung-ngor CHAN ; Yan Chou YE ; Wing Hung TAM ; Xilin YANG ; Ronald Ching-wan MA
Diabetes & Metabolism Journal 2025;49(1):128-143
Background:
The genetic basis for hyperglycaemia in pregnancy remain unclear. This study aimed to uncover the genetic determinants of gestational diabetes mellitus (GDM) and investigate their applications.
Methods:
We performed a meta-analysis of genome-wide association studies (GWAS) for GDM in Chinese women (464 cases and 1,217 controls), followed by de novo replications in an independent Chinese cohort (564 cases and 572 controls) and in silico replication in European (12,332 cases and 131,109 controls) and multi-ethnic populations (5,485 cases and 347,856 controls). A polygenic risk score (PRS) was derived based on the identified variants.
Results:
Using the genome-wide scan and candidate gene approaches, we identified four susceptibility loci for GDM. These included three previously reported loci for GDM and type 2 diabetes mellitus (T2DM) at MTNR1B (rs7945617, odds ratio [OR], 1.64; 95% confidence interval [CI],1.38 to 1.96]), CDKAL1 (rs7754840, OR, 1.33; 95% CI, 1.13 to 1.58), and INS-IGF2-KCNQ1 (rs2237897, OR, 1.48; 95% CI, 1.23 to 1.79), as well as a novel genome-wide significant locus near TBR1-SLC4A10 (rs117781972, OR, 2.05; 95% CI, 1.61 to 2.62; Pmeta=7.6×10-9), which has not been previously reported in GWAS for T2DM or glycaemic traits. Moreover, we found that women with a high PRS (top quintile) had over threefold (95% CI, 2.30 to 4.09; Pmeta=3.1×10-14) and 71% (95% CI, 1.08 to 2.71; P=0.0220) higher risk for GDM and abnormal glucose tolerance post-pregnancy, respectively, compared to other individuals.
Conclusion
Our results indicate that the genetic architecture of glucose metabolism exhibits both similarities and differences between the pregnant and non-pregnant states. Integrating genetic information can facilitate identification of pregnant women at a higher risk of developing GDM or later diabetes.
10.Recommendations for enhanced primary series (third dose) COVID-19 vaccination for people with rheumatic diseases: chapter of Rheumatologists, College of Physicians, Singapore.
Chuanhui XU ; Manjari LAHIRI ; Amelia SANTOSA ; Li-Ching CHEW ; Stanley ANGKODJOJO ; Melonie SRIRANGANATHAN ; Warren FONG ; Thaschawee ARKACHAISRI ; Ernest SURESH ; Kok Ooi KONG ; Aisha LATEEF ; Tau Hong LEE ; Keng Hong LEONG ; Andrea LOW ; Teck Choon TAN ; Ying-Ying LEUNG
Singapore medical journal 2025;66(10):532-539
INTRODUCTION:
This review aims to provide evidence-based recommendations for an enhanced primary series (third dose) coronavirus disease 2019 (COVID-19) vaccination in people with rheumatic diseases (PRDs) in the local and regional context.
METHODS:
Literature reviews were performed regarding the necessity, efficacy, safety and strategies for enhanced primary series COVID-19 vaccination in PRDs. Recommendations were developed based on evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. Evidence was synthesised by eight working group members, and the consensus was achieved by a Delphi method with nine members of an expert task force panel.
RESULTS:
Two graded recommendations and one ungraded position statement were developed. PRDs have impaired immunogenicity from the COVID-19 vaccine and are at an increased risk of postvaccine breakthrough severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and poor clinical outcomes, compared to the general population. We strongly recommend that PRDs on immunomodulatory drugs be offered a third dose of the messenger RNA (mRNA) vaccine as part of an enhanced primary series, after the standard two-dose regimen. We conditionally recommend that the third dose of mRNA vaccine against SARS-CoV-2 be given at least 4 weeks after the second dose or as soon as possible thereafter. There is insufficient data to inform whether the third mRNA vaccine should be homologous or heterologous in PRDs.
CONCLUSION
These recommendations that were developed through evidence synthesis and formal consensus process provide guidance for an enhanced primary series COVID-19 vaccination in PRDs.
Humans
;
COVID-19/prevention & control*
;
COVID-19 Vaccines/administration & dosage*
;
Rheumatic Diseases/immunology*
;
Singapore
;
SARS-CoV-2
;
Vaccination/methods*
;
Delphi Technique
;
Immunization, Secondary

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