Measuring anterior chamber depth with Orbscan Topography System

• Published in: Journal of cataract and refractive surgery Vol. 23; no. 9; p. 1351
• Main Authors: Auffarth, G U, Tetz, M R, Biazid, Y, Völcker, H E
• Format: Journal Article
• Language: English
• Published: United States 01-11-1997
• Subjects: Aged; Anterior Chamber - anatomy & histology; Anterior Chamber - diagnostic imaging; Corneal Topography - instrumentation; Humans; Ophthalmology - instrumentation; Reproducibility of Results; Ultrasonography - instrumentation
• ISSN: 0886-3350
• DOI: 10.1016/S0886-3350(97)80114-9

To assess the reliability of the Orbscan Topography System in measuring anterior chamber depth (ACD).
Department of Ophthalmology, Ruprecht-Karls-University of Heidelberg, Heidelberg, Germany.
The Orbscan Topography System is a 3-D, scanning slit beam system for analyzing corneal surfaces as well as structures of the anterior segment, e.g., iris, lens. Reflected surface data points are measured in the x, y, and z axes, creating color-coded true surface topography maps. We measured ACD prior to cataract surgery in 56 eyes of 37 patients (mean age 70.4 years + 13.2 [SD]) using the Orbscan system and, as a control, the Grieshaber Biometric System (ultrasound) and the Jäger ACD slitlamp measurement system.
Mean ACD values measured with the Orbscan system were 3.23 +/- 0.55 mm; ultrasound measurements were 3.27 +/- 0.54 mm and Jäger measurements, 3.10 +/- 0.55 mm. The average difference between Orbscan and ultrasound values was 0.04 +/- 0.15 mm. The correlation coefficient between Orbscan and ultrasound was 0.96 (P < .00001) and between Orbscan and Jäger, 0.899 (P < .0001).
The ACD measurements by the Orbscan system were equivalent to common reference measurements.