Calculation of body surface area via computed tomography–guided modeling in domestic rabbits (Oryctolagus cuniculus)

Abstract

Objective To optimize the use of CT-guided modeling for the calculation of body surface area (BSA) in domestic rabbits (Oryctolagus cuniculus). Animals 12 domestic rabbits. Procedures Adult rabbits (body weight, 1 to > 4 kg) that were client-owned animals undergoing CT for disease diagnosis or deceased laboratory animals donated from other research projects were scanned with a CT scanner. Images were transferred to a radiation therapy planning software program. Image slices were captured as contiguous slices at 100 kVp and 100 mA and processed to 0.1-cm-thick sections. The length of each contoured slice was summed to calculate a final BSA measurement. Nonlinear regression analysis was then used to derive an equation for the calculation of BSA in rabbits. Results The constant calculated by use of this method was 9.9 (range, 9.59 to 10). The R2 for the goodness of fit was 0.9332. The equation that best described BSA as a function of body weight for domestic rabbits with this method was as follows: BSA = (9.9 × [body weight {in grams}]2/3)/10,000. Conclusions and Clinical Relevance The BSA calculated via the CT-guided method yielded results similar to those obtained with equations for other similarly sized mammals and verified the use of such equations for rabbits. Additionally, this technique can be used for species that lack equations for the accurate calculation of BSA.

Measurements of body surface area and volume in laboratory rabbits (New Zealand White rabbits) using a computed tomography scanner

“…The present k value was larger than the k value (9.9) of rabbits (NZW, Mini-lop, Netherland Dwarf, Dutch Belted, Chinchilla, Flemish Giant, and breed unknown) analyzed the CT images using their own procedure reported by Zehnder [ 15 ]. The surface area of the small cuboid was computed to be 0.111 ± 0.001 m 2 (mean ± SD) from the MPR of CT images by Zehnder’s procedure (i.e., summing the lengths of contour for each slice and multiplying this total length by the reconstruction interval.…”

“…The surface area of the small cuboid was computed to be 0.111 ± 0.001 m 2 (mean ± SD) from the MPR of CT images by Zehnder’s procedure (i.e., summing the lengths of contour for each slice and multiplying this total length by the reconstruction interval. Additionally, the areas of the end slices were added to this value [ 15 ]). The average value computed by Zehnder’s procedure was 80.4% of the calculated value (0.138 m 2 ).…”

“…measured the BSA of 12 rabbits (multiple breeds of rabbits including New Zealand White rabbits [NZW]) using a CT scanner and analyzed the CT images using their own procedure. They reported the k value for rabbits to be 9.9 [ 15 ]. In the present study, we measured the BSA of 72 laboratory rabbits (NZW) using a CT scanner and employing our measurement methods to verify the k value of laboratory rabbits.…”

Use of computed tomography and radiation therapy planning software to develop a novel formula for body surface area calculation in dogs

“…Computed tomography (CT) modeling has been used to formulate a K constant in rabbits. In that study, CT images from 12 pet rabbits were transferred to radiation therapy planning software and 1 mm slices were used to generate the surface contours to determine BSA, and nonlinear regression was then used in the current formula to generate a K constant of 9.9 . This was similar to another CT‐based derivation of a BSA formula for ferrets which yielded a K constant of 9.94 with the help of 3D surface modeling using open‐source imaging software to determine BSA .…”

Measurements of body surface area and volume in male Japanese White rabbits using a computed tomography scanner: comparison with male New Zealand White rabbits

“…The k values (100 × BSA [m 2 ] = k × BW [kg] 2/3 , i.e., Meeh’s formula) for various animal species have been reported and used to extrapolate the test results between species. To date, the k values for rabbits have been calculated in various ways; k values of 5.7 to 10.0 were determined by use of skinning and triangulation reported by Spector [16], while values of 12.0 to 12.9 were reported by Fougère and Wynn who did not show the method of BSA determination [4], and Zehnder et al reported a k value of 9.9 analyzed the Computed tomography (CT) images using their own procedure [17]. Additionally, Bai et al reported 7-month old male JW (working BW range: 2.5 to 3.0 kg) k values of 11.30 to 11.35 determined by use of paper cover and skinning [1].…”