Purchase this article with an account.
Julien PLAT, Arnaud Payerols, Max Villain, Didier Hoa, Vincent Daien; Biometric factors associated with effective lens position in capsular bag after cataract surgery. Invest. Ophthalmol. Vis. Sci. 2016;57(12):923.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Effective lens position (ELP) in the capsular bag is one of the main factor of refractive outcome after cataract surgery, as suggested by Olsen and al. The aim of this study is to investigate the clinical and biometrical factors associated with ELP depends of the type of intraocular lens (IOL) we use.
This is a single-center prospective study conducted in the public hospital of Montpellier between 2012 and 2015, from patients who underwent uncomplicated standard phacoemulsification. We collected clinical factors (age, sex, history, refraction, keratometry, vitreous status) and biometrical factors (axial length, pachymetry, anterior chamber depth, lens thickness, white to white) which may affect ELP. Optical biometry was performed preoperatively and one month postoperatively. Power and type of IOL were collected to stratify patients into 3 groups: SN60WF Alcon®, ZCB00 Tecnis®, Asphina409MV Zeiss®. ELP was measured by the c constant as described by Olsen et al.
244 eyes from 181 patients were included (mean age 73.1 ± 9.3 years). The c constant was respectively 0.38 ± 0.04, 0.44 ± 0.05, 0.39 ± 0.06 for the 3 groups SN60WF, ZCB00, ASPHINA. The anterior chamber depth and anterior segment depth were two factors significantly correlated with ELP (r = -0.44, p <0.0001; r = -0.31, p <0.0001, respectively). The lens thickness was positively correlated with ELP for ASPHINA IOL only (r = 0.52, p = 0.006). The age, sex, refraction, keratometry, white to white, axial length, vitreous status showed no significant correlation with ELP.
Estimating ELP by current formulas is probably one main source of postoperative refractive error. The current formulas such as SRK/T estimate ELP from keratometry and axial length, without taking into account the anterior segment anatomy. However, anterior segment anatomy is not always correlated to the axial length in particular with extreme myopic and hyperopic eyes. The latest generation of formulas, such as Olsen and Barrett formulas, take more parameters into account to better estimate the ELP. This study found that the ELP is correlated to anterior chamber depth and anterior segment depth. The integration of these data in formulas may improve the refractive outcome after cataract surgery.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.
This PDF is available to Subscribers Only