The study was done to investigate agreement between biometric measurements obtained from the Lenstar LS 900 (Haag-Streit AG) based on OLCR and the Tomey OA-2000 (Tomey Corporation) based on SS-OCT in dense cataracts.
124 eyes of 76 patients were analysed. Intraocular lens prediction errors and absolute prediction errors were assessed based on postoperative manifest refraction. Analyses used were paired t test, Pearson correlation coefficient (r), and Bland-Altman plots.
Failure in axial length measurements was noted in 28 eyes (22.58%) with OCLR compared to 2 eyes (1.6%) with SS-OCT. Although not statistically significant, axial length measurements were clinically higher with SS-OCT (23.78 ± 1.76 mm) compared to OCLR (23.72 ± 1.58 mm) (P = .81) (r = 0.23; P = .01). There was a significant trend toward myopic intraocular lens prediction with SS-OCT (−0.09 ± 0.48) compared to OLCR (0.09 ± 0.41, P < .01) (r = 0.25, P = .01). There was good agreement for keratometric and ACD values between the two devices. SS-OCT gave significantly higher values of lens thickness compared to OCLR (4.44 ± 0.44 vs 4.18 ± 0.48 mm, P < .01) (r = 0.39, P < .01). CCT measured with OCLR was significantly higher than SS-OCT (525.64 ± 27.0 vs 513.21 ± 29.24 µm; P < .01) (r = 0.98, P < .01).
The study concluded that one-fifth of the patients with dense cataracts failed axial length measurement on OCLR. SS-OCT gives clinically higher axial length measurements leading to more myopic intraocular lens prediction errors postoperatively. OCLR provides higher pachymetry and lower lens thickness values compared to the SS-OCT device.
Reference: https://doi.org/10.3928/1081597X-20200612-03