Comparative study of anterior segment measurement with rotating dual Scheimpflug analyzer and optical low coherence reflectometry

Abstract

AbstractPurpose The aim of the study was to compare the anterior segment measurements obtained with optical low coherence reflectometry (Lenstar LS 900, version 1.1, Haag‐Streit, Koeniz, Switzerland) and rotating dual Scheimpflug analyzer (Galilei Dual Scheimpflug Analyzer versión 3, Ziemer Ophthalmic Systems, Port, Switzerland).Methods Prospective, comparative, observational study in which 59 eyes of 30 patients who needed a preoperative study for a refractive procedure or cataract surgery were studied with both the Lenstar 900 and Galilei systems. Central corneal thickness (CCT), anterior chamber depth (ACD), horizontal limbal distance (white‐to‐white distance; WTW), pupil diameter (PD), as well as the keratometric readings at the steepest meridian (Ks), the flattest meridian (Kf), the corneal astigmatism power, and the plus astigmatic cylinder axis were measured. Degree of agreement between Ks, Kf, astigmatism power, cylinder axis, CCT, ACD, WTW and PD were the main outcome measures.Results Ks, Kf, corneal astigmatism power, cylinder axis, and WTW measurements with the Lenstar and the Galilei system showed narrow 95% limits of agreement (LoA), which implies good agreement (p>0.05, Bland‐Altman plot analysis). In contrast, range and 95% LoA were significantly different for CCT, ACD and PD values (p<0.05, Bland‐Altman plot analysis).Conclusion In clinical practice, the Lenstar and the Galilei system can be used interchangeably for WTW measurements and K readings but not for CCT, ACD and PD values.