Estimation of breast prosthesis volume by the Cavalieri principle using magnetic resonance images

The purpose of this study was to search the accuracy and reproducibility of the Cavalieri method for the estimation of the breast prosthesis volume on magnetic resonance images (MRI).

Nine breast prostheses were scanned in axial and coronal section planes by MRI. The consecutive sections in 5-mm thickness were taken, after which the volumes of the prostheses were measured and estimated by means of the fluid displacement technique and three-dimensional postprocessing software, respectively. The volumes of the prostheses also were estimated by three performers using the Cavalieri principle to check the accuracy and interobserver interrelation of the suggested technique

There were no significant differences between the Cavalieri estimate and the real volumes of the breast prostheses (p > 0.05), nor between the performers's volume estimates (p > 0.05). The orientation of the section planes did not affect the accuracy of the estimates (p > 0.05)

This report describes a rapid, simple, accurate, and practical technique for estimating the volume of the breast prostheses without changing the routine process in the clinics. It was concluded that the combination of MRI with the Cavalieri principle is a direct and accurate technique that can be applied safely for estimating the volume of the breast prosthesis in 4 min and 34 s per prosthesis.