Abstract
OBJECTIVES: Measurement of white-to-white (WtW) distance is essential in the pre-operative evaluation of candidates for cataract or refractive surgery, and in determining the appropriate haptic size of newly developed phakic intraocular lenses (IOLs). This distance can be measured quickly and easily using various methods. However, inconsistencies among reported results raise concerns about whether these measurements can be used interchangeably. Although previous studies have analyzed the agreement between different devices, there has been no such study conducted at the national level. Based on this, our study aimed to analyze the agreement between WtW measurements obtained by the IOLMaster 500 and Pentacam devices for use in phakic IOL (pIOL) calculations. METHODS: A total of 66 eyes from 66 candidates for cataract or refractive surgery were included in the study. WtW distance measurements obtained from both devices were recorded and analyzed. A one-sample t-test was used to compare the mean WtW values. Bland-Altman analysis was performed to assess the agreement between the two devices. RESULTS: The mean age of the participants was 63.42±18.27 years, and 20 (60.6%) were male. The mean WtW distances measured by the IOLMaster 500 and Pentacam were 11.80±0.48 mm and 11.50±0.56 mm, respectively (p<0.001) (limits of agreement: Lower limit 0.19, upper limit 0.41; 95% confidence interval). CONCLUSION: Our study showed that the IOLMaster 500 measured significantly higher WtW distances compared to the Pentacam. Therefore, these two devices should not be used interchangeably for WtW measurements. We recommend using the devices endorsed by the chosen pIOL manufacturer.