title: Comparison of anterior chamber depth measurements using the IOLMaster, scanning peripheral anterior chamber depth analyser, and anterior segment optical coherence tomography.
abstract: OBJECTIVE
  To compare anterior chamber depth measurements by three non-contact devices-the IOLMaster, scanning peripheral anterior chamber depth analyser (SPAC), and Visante anterior segment optical coherence tomography (AS-OCT) METHODS: Prospective, cross sectional study of 497 phakic subjects over 50 years of age attending a community clinic in Singapore. Anterior chamber depth of the right eye was measured using all three techniques by the same investigator. Depth measurements were made from the corneal epithelium to the anterior lens surface. The values obtained were compared using Bland-Altman analysis.
  
  
  RESULTS
  232 men and 265 women were examined (mean (SD) age, 63.4 (7.9) years). Mean anterior chamber depth was 3.08 (0.36) mm with IOLMaster, 3.10 (0.44) mm with SPAC, and 3.14 (0.34) mm with AS-OCT. A significant difference was present between the anterior chamber depth measurements recorded by the three devices (p<0.0001). Mean differences between the measurements were: AS-OCT v IOLMaster, 0.062 (0.007) mm (95% limits of agreement, -0.37 to 0.25 mm) (p<0.0001); AS-OCT v SPAC, 0.035 (0.011) mm (-0.44 to 0.51 mm) (p = 0.0001); SPAC v IOLMaster, 0.027 (0.012) mm (-0.57 to 0.50 mm) (p = 0.027).
  
  
  CONCLUSIONS
  AS-OCT gave systematically deeper anterior chamber measurements than SPAC and IOL-Master. However, as the differences found were small they are unlikely to be clinically important.
authors.affiliation: Glaucoma Department, Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore 168751.
authors.forename: Raghavan
authors.initials: R
authors.lastname: Lavanya
authors.forename: Livia
authors.initials: L
authors.lastname: Teo
authors.forename: David S
authors.initials: DS
authors.lastname: Friedman
authors.forename: Han T
authors.initials: HT
authors.lastname: Aung
authors.forename: Mani
authors.initials: M
authors.lastname: Baskaran
authors.forename: Hong
authors.initials: H
authors.lastname: Gao
authors.forename: Tamuno
authors.initials: T
authors.lastname: Alfred
authors.forename: Steve K
authors.initials: SK
authors.lastname: Seah
authors.forename: Kenji
authors.initials: K
authors.lastname: Kashiwagi
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Foster
authors.forename: Tin
authors.initials: T
authors.lastname: Aung
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000867:Anterior Chamber / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D003315:Cornea / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D003430:Cross-Sectional Studies; D003941:Diagnostic Techniques, Ophthalmological; D005260:Female; D006801:Humans; D007908:Lens, Crystalline / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012846:Singapore / Q000453:epidemiology; D041623:Tomography, Optical Coherence / Q000379:methods*; D014463:Ultrasonography