Immersion B-guided versus contact A-mode biometry for accurate measurement of axial length and intraocular lens power calculation in siliconized eyes.

PURPOSE: To compare the accuracy of the immersion B-guided versus the contact A-mode biometry in measuring the axial length and intraocular lens power of the siliconized eyes.
METHODS: Sixty eyes with silicone cataract were divided into two groups. In Group A, the axial length of 30 eyes was measured by contact A-mode biometry. In Group B, the axial length of 30 eyes was measured by immersion B-guided biometry. The postoperative refraction was done after 3 months and was compared with the attempted values.
RESULTS: Twenty-five eyes of the B-guided group (83.3%) achieved a refraction deviation of ± 1 D or less versus 14 (46.6%) in the A-mode group. The mean refractive deviation was less with the B-mode (0.15 ± 0.94) versus contact A-mode (-0.95 ± 1.157); the difference is statistically significant (P = 0.024, Fisher test).
CONCLUSION: B-guided biometry was found to be more accurate than the contact method in measuring axial length and intraocular lens power calculation in siliconized eyes and spared the time and cost needed for a separate B-scan.