PMID- 37793787
OWN - NLM
STAT- Publisher
LR  - 20240507
IS  - 1468-2079 (Electronic)
IS  - 0007-1161 (Linking)
DP  - 2023 Oct 4
TI  - Investigating the determinants of iridolenticular contact area: a novel parameter 
      for angle closure.
LID - bjo-2022-322810 [pii]
LID - 10.1136/bjo-2022-322810 [doi]
AB  - BACKGROUND/AIMS: To identify ocular determinants of iridolenticular contact area 
      (ILCA), a recently introduced swept-source optical coherence tomography (SSOCT) 
      derived parameter, and assess the association between ILCA and angle closure. 
      METHODS: In this population-based cross-sectional study, right eyes of 464 
      subjects underwent SSOCT (SS-1000, CASIA, Tomey Corporation, Nagoya, Japan) 
      imaging in the dark. Eight out of 128 cross-sectional images (evenly spaced 22.5 degrees  
      apart) were selected for analysis. Matlab (Matworks, Massachusetts, USA) was used 
      to measure ILCA, defined as the circumferential extent of contact area between 
      the pigmented iris epithelium and anterior lens surface. Gonioscopic angle 
      closure (GAC) was defined as non-visibility of the posterior trabecular meshwork 
      in two or more angle quadrants. RESULTS: The mean age of subjects was 62+/-6.6 
      years, with the majority being female (65.5%). 143/464 subjects (28.6%) had GAC. 
      In multivariable linear regression analysis, ILCA was significantly associated 
      with anterior chamber width (beta=1.03, p=0.003), pupillary diameter (beta=-1.9, 
      p<0.001) and iris curvature (beta=-17.35, p<0.001). ILCA was smaller in eyes with 
      GAC compared with those with open angles (4.28+/-1.6 mm(2) vs 6.02+/-2.71 mm(2), 
      p<0.001). ILCA was independently associated with GAC (beta=-0.03, p<0.001), 
      iridotrabecular contact index (beta=-6.82, p<0.001) or angle opening distance 
      (beta=0.02, p<0.001) after adjusting for covariates. The diagnostic performance of 
      ILCA for detecting GAC was acceptable (AUC=0.69). CONCLUSIONS: ILCA is a 
      significant predictor of angle closure independent of other biometric factors and 
      may reflect unique anatomical information associated with pupillary block. ILCA 
      represents a novel biometric risk factor in eyes with angle closure.
CI  - (c) Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and 
      permissions. Published by BMJ.
FAU - Tun, Tin A
AU  - Tun TA
AUID- ORCID: 0000-0001-7649-6952
AD  - Singapore Eye Research Institute and Singapore National Eye Centre, Singapore.
AD  - Duke-NUS Medical School, Singapore.
FAU - Nongpiur, Monisha Esther
AU  - Nongpiur ME
AUID- ORCID: 0000-0003-2372-8523
AD  - Singapore Eye Research Institute and Singapore National Eye Centre, Singapore.
AD  - Duke-NUS Medical School, Singapore.
FAU - Xu, Benjamin Y
AU  - Xu BY
AUID- ORCID: 0000-0003-1573-988X
AD  - Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine, 
      University of Southern California, Los Angeles, California, USA.
FAU - Wang, Xiaofei
AU  - Wang X
AUID- ORCID: 0000-0002-3175-0344
AD  - Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, 
      Beijing Advanced Innovation Center for Biomedical Engineering, School of 
      Biological Science and Medical Engineering, Beihang University, Beijing, China.
FAU - Tan, Marcus
AU  - Tan M
AD  - Singapore Eye Research Institute and Singapore National Eye Centre, Singapore.
AD  - Ophthalmology Service, Jurong Health Service, Singapore.
FAU - Quah, Joanne Hui Min
AU  - Quah JHM
AD  - SingHealth Polyclinics, Outram, Singapore.
FAU - Lim, Hou-Boon
AU  - Lim HB
AD  - Singapore Eye Research Institute and Singapore National Eye Centre, Singapore.
FAU - Cheng, Ching Yu
AU  - Cheng CY
AD  - Singapore Eye Research Institute and Singapore National Eye Centre, Singapore.
AD  - Duke-NUS Medical School, Singapore.
FAU - Aung, Tin
AU  - Aung T
AUID- ORCID: 0000-0002-7916-0589
AD  - Singapore Eye Research Institute and Singapore National Eye Centre, Singapore 
      aung.tin@snec.com.sg.
AD  - Duke-NUS Medical School, Singapore.
LA  - eng
PT  - Journal Article
DEP - 20231004
PL  - England
TA  - Br J Ophthalmol
JT  - The British journal of ophthalmology
JID - 0421041
SB  - IM
OTO - NOTNLM
OT  - Anterior chamber
OT  - Glaucoma
OT  - Imaging
OT  - Iris
OT  - Lens and zonules
COIS- Competing interests: None declared.
EDAT- 2023/10/05 01:00
MHDA- 2023/10/05 01:00
CRDT- 2023/10/04 21:13
PHST- 2022/10/26 00:00 [received]
PHST- 2023/08/03 00:00 [accepted]
PHST- 2023/10/05 01:00 [medline]
PHST- 2023/10/05 01:00 [pubmed]
PHST- 2023/10/04 21:13 [entrez]
AID - bjo-2022-322810 [pii]
AID - 10.1136/bjo-2022-322810 [doi]
PST - aheadofprint
SO  - Br J Ophthalmol. 2023 Oct 4:bjo-2022-322810. doi: 10.1136/bjo-2022-322810.