Quantification of Trabecular-Iris Contact and its Prevalence by Optical Coherence Tomography in a Healthy Caucasian Population

Abstract

Purpose

To determine the prevalence of trabecular-iris contact (TIC) and quantify this contact in healthy Caucasian individuals using Fourier-domain optical coherence tomography (FD-OCT).

Methods

For this cross-sectional study, 2,012 eyes of 1,006 healthy subjects were recruited among individuals undergoing a routine ophthalmologic checkup. In each participant, age, sex, intraocular pressure, and spherical refractive error were first recorded along with anterior chamber depth and volume, central corneal thickness measured with the Pentacam, and axial length with the IOLMaster. Anterior chamber angle variables and the presence of TIC in the horizontal quadrants were determined by anterior segment FD-OCT (RTVue 100®). When TIC was observed, TIC length (TICL) and its percentage in relation to the length of the trabecular meshwork (TICL percentage) were also measured.

Results

Trabecular-iris contact in the horizontal quadrants was observed in 34 eyes of 25 patients, representing 1.6% of the total number of eyes examined. In this subgroup of individuals, mean age was 55.8 years, 84% were women, and spherical refractive error ranged from -0.25 to 8.25 D. Eyes with TIC showed an angle width of less than 23.2 degrees and axial length shorter than 23.7 mm. Mean TICL was 239 ± 79 μm (103-495 μm) and mean TICL percentage was 46.9% ± 13.9% (17.2%-76.3%).

Conclusions

The prevalence of TIC was low in this population. Fourier-domain optical coherence tomography emerged as useful to assess its prevalence and quantify the extent of TIC.

Keywords

Angle closure Appositional contact Glaucoma Optical coherence tomography Trabecular-iris contact

Get full access to this article

View all access options for this article.

References

Quigley

Broman

The number of people with glaucoma worldwide in 2010 and 2020.

Br J Ophthalmol 200690(3)262–267

Nolan

Aung

Machin

et al.

Detection of narrow angles and established angle closure in Chinese residents of Singapore: potential screening tests.

Am J Ophthalmol 2006141(5)896–901

Foster

Buhrmann

Quigley

Johnson

The definition and classification of glaucoma in prevalence surveys.

Br J Ophthalmol 200286(2)238–242

Cao

Wang

Chen

Jonas

Anterior chamber depth and chamber angle and their associations with ocular and general parameters: the Beijing Eye Study.

Am J Ophthalmol 2008145(5)929–936

Friedman

Gazzard

Min

et al.

Age and sex variation in angle findings among normal Chinese subjects: a comparison of UBM, Scheimpflug, and gonioscopic assessment of the anterior chamber angle.

J Glaucoma 200817(1)5–10

Amerasinghe

Foster

Wong

et al.

Variation of angle parameters in asians: an anterior segment optical coherence tomography study in a population of singapore malays.

Invest Ophthalmol Vis Sci 200950(6)2626–2631

Fernández-Vigo

García-Feijóo

Martínez-de-la-Casa

et al.

Fourier domain optical coherence tomography to assess the iridocorneal angle and correlation study in a large Caucasian population.

BMC Ophthalmol 2016 16 42

Thomas

George

Parikh

Muliyil

Jacob

Five year risk of progression of primary angle closure suspects to primary angle closure: a population based study.

Br J Ophthalmol 200387(4)450–454

Kong

Foster

Huang

et al.

Appositional closure identified by ultrasound biomicroscopy in population-based primary angle-closure glaucoma suspects: the Liwan eye study.

Invest Ophthalmol Vis Sci 201152(7)3970–3975

10.

Smith

Singh

Lin

et al.

Evaluation of the anterior chamber angle in glaucoma: a report by the american academy of ophthalmology.

Ophthalmology 2013120(10)1985–1997

11.

Sihota

Lakshmaiah

Walia

Sharma

Pailoor

Agarwal

The trabecular meshwork in acute and chronic angle closure glaucoma.

Indian J Ophthalmol 200149(4)255–259

12.

Radhakrishnan

Goldsmith

Huang

et al.

Comparison of optical coherence tomography and ultrasound biomicroscopy for detection of narrow anterior chamber angles.

Arch Ophthalmol 2005123(8)1053–1059

13.

Dada

Sihota

Gadia

Aggarwal

Mandal

Gupta

Comparison of anterior segment optical coherence tomography and ultrasound biomicroscopy for assessment of the anterior segment.

J Cataract Refract Surg 200733(5)837–840

14.

Kunimatsu

Tomidokoro

Mishima

et al.

Prevalence of appositional angle closure determined by ultrasonic biomicroscopy in eyes with shallow anterior chambers.

Ophthalmology 2005112(3)407–412

15.

Nongpiur

Gong

Lee

et al.

Subgrouping of primary angle-closure suspects based on anterior segment optical coherence tomography parameters.

Ophthalmology 201312012 2525–2531

16.

Nolan

See

Chew

et al.

Detection of primary angle closure using anterior segment optical coherence tomography in Asian eyes.

Ophthalmology 2007114(1)33–39

17.

Quek

Narayanaswamy

Tun

et al.

Comparison of two spectral domain optical coherence tomography devices for angle-closure assessment.

Invest Ophthalmol Vis Sci 201253(9)5131–5136

18.

Wylegała

Teper

Nowińska

Milka

Dobrowolski

Anterior segment imaging: Fourier-domain optical coherence tomography versus time-domain optical coherence tomography.

J Cataract Refract Surg 200935(8)1410–1414

19.

Fernández-Vigo

García-Feijóo

Martínez-de-la-Casa

García-Bella

Fernández-Vigo

Morphometry of the trabecular meshwork in vivo in a healthy population using fourier-domain optical coherence tomography.

Invest Ophthalmol Vis Sci 201556(3)1782–1788

20.

Barkana

Dekel

Goldich

Morad

Avni

Zadok

Angle closure in Caucasiansa pilot, general ophthalmology clinic-based study.

J Glaucoma 201221(5)337–341

21.

Kagemann

Wollstein

Ishikawa

et al.

Identification and assessment of Schlemms canal by spectral-domain optical coherence tomography.

Invest Ophthalmol Vis Sci 201051(8)4054–4059

22.

Liu

Lam

Leung

Anterior chamber angle imaging with swept-source optical coherence tomography: an investigation on variability of angle measurement.

Invest Ophthalmol Vis Sci 201152(12)8598–8603

23.

Tan

Sauren

de Brabander

et al.

Reproducibility of anterior chamber angle measurements with anterior segment optical coherence tomography.

Invest Ophthalmol Vis Sci 201152(5)2095–2099

24.

Fernández-Vigo

Macarro-Merino

Fernández-Vigo

et al.

Effects of Implantable Collamer Lens V4c Placement on Iridocorneal Angle Measurements by Fourier-Domain Optical Coherence Tomography.

Am J Ophthalmol 2016 162 43 52.e1

25.

Mishima

Tomidokoro

Suramethakul

et al.

Iridotrabecular contact observed using anterior segment three-dimensional OCT in eyes with a shallow peripheral anterior chamber.

Invest Ophthalmol Vis Sci 201354(7)4628–4635

26.

Friedman

See

et al.

Degree of angle closure and extent of peripheral anterior synechiae: an anterior segment OCT study.

Br J Ophthalmol 200892(1)103–107

27.

Lai

Mak

Lai

Lam

Leung

Anterior chamber angle imaging with swept-source optical coherence tomography: measuring peripheral anterior synechia in glaucoma.

Ophthalmology 2013120(6)1144–1149

28.

Chong

Sakata

Narayanaswamy

et al.

Relationship between intraocular pressure and angle configuration: an anterior segment OCT study.

Invest Ophthalmol Vis Sci 201354(3)1650–1655

29.

Foster

Baasanhu

Alsbirk

Munkhbayar

Uranchimeg

Johnson

Glaucoma in Mongolia.

A population-based survey in Hövsgöl province, northern Mongolia. Arch Ophthalmol 1996114(10)1235–1241

30.

Bhargava

Leighton

Phillips

Early angle-closure glaucoma.

Distribution of iridotrabecular contact and response to pilocarpine. Arch Ophthalmol 197389(5)369–372

31.

Ang

Wells

Factors influencing laser peripheral iridotomy outcomes in white eyes: an anterior segment optical coherence tomography study.

J Glaucoma 201120(9)577–583

32.

Barkana

Dorairaj

Gerber

Liebmann

Ritch

Agreement between gonioscopy and ultrasound biomicroscopy in detecting iridotrabecular apposition.

Arch Ophthalmol 200712510 1331–1335