Performance of three biometry devices in patients with different grades of age-related cataract

The new Lenstar biometry device was compared in a typical clinical setting to the IOL-Master and Visante-OCT.

Fifty-one eyes of 51 patients with age-related cataract were examined with Lenstar LS900 (Haag Streit AG) biometer, IOL-Master V.5 (Carl Zeiss Meditec AG) and Visante-OCT (Carl Zeiss Meditec AG) before cataract surgery. Central corneal thickness (CCT), anterior chamber depth (ACD), keratometry readings of flattest and steepest meridian (K), corneal radius (R) and axial length (AL) values were correlated. Cataracts were graded according to the Lens Opacities Classification System III (LOCS) regarding nuclear colour (NC), nuclear opalescence (NO), cortical (C) and posterior subcapsular (P) cataract.

Mean values and standard deviations for AL, K and R was 23.66 ± 1.23 mm and 23.67 ± 1.26 mm, 43.24 ± 1.69 dpt and 43.16 ± 1.71 dpt, 7.68 ± 0.29 mm and 7.70 ± 0.28 mm with the IOL-Master and with the LS900, respectively (r = 0.99 and p = 0.76, r = 0.99 and p = 0.029, r = 0.89 and p = 0.14, respectively). Visante-OCT demonstrated highest values of three devices regarding to ACD followed by Lenstar LS900 and IOLMaster. Axial length measurements were unfeasible in 10% of the cases (five patients) and this significantly correlated with the presence of posterior subcapsular cataract of LOCS III grade 4.0 or higher.

IOL-Master, Lenstar LS900 and AC–OCT proved to be excellent non-contact measurement methods in eyes with age-related cataract. Nevertheless, ultrasound biometry is still required for cases with dense posterior subcapsular cataract.