The Use of A-Mode and B-Mode Ultrasound for Ocular Biometry in Domestic Cats

Abstract

Ultrasonographic ocular biometry has its value well established, however, regarding domestic cats, some data are incomplete in the literature. The objectives of this study were to perform ocular biometry in domestic cats by two different ultrasound modes, and to compare the results. This study included 15 adult cats, totaling 30 eyes without macroscopic changes. Rostrocaudaly measurements of the eyeball (EB), anterior chamber (AC), lens (L) and vitreous chamber (VC) were made by A-mode and B-mode ultrasonography, using sagittal plane and transcorneal technique. Statistical analysis was performed by tukey test (5%). Means and standard deviations of the measurements obtained by A-mode and B-mode ultrasound, respectively, in millimeters: EB: 19.83 ± 0.52, 20.11 ± 0.81; AC: 4.20 ± 0.48, 3.95 ± 0.47; L: 6.98 ± 0.34, 8.12 ± 0.43; VC: 7.98 ± 0.39, 7.13 ± 0.63. Statistical difference was observed among the measurements of L and VC when comparing the two sonographic methods. The values of ocular biometry in healthy cats presented in this study are important bases for diagnosing of diseases. However, the differences in the values obtained by A-mode and B-mode ultrasound, highlights the need for further studies to determine which method provides more reliable measurements.