Research Article

Comparison of CT-Derived Prostate Volume Measurements Using Three-Dimensional Segmentation and the Ellipsoid Formula in Intact Male Dogs

Number: 2026 October 21, 2026
EN TR

Comparison of CT-Derived Prostate Volume Measurements Using Three-Dimensional Segmentation and the Ellipsoid Formula in Intact Male Dogs

Abstract

This retrospective study compared prostate volumes obtained from computed tomography images using three-dimensional segmentation and the ellipsoid formula. Archived CT examinations of eight intact male dogs with radiological findings consistent with prostatic hyperplasia were included. The prostate was manually delineated on consecutive transverse images using 3D Slicer, and segmentation-based volume was calculated automatically. Prostatic length, height, and width were measured, and ellipsoid volume was calculated using the formula V = H × W × L × 0.523. Paired measurements were compared using the Wilcoxon signed-rank test. The relationship and agreement between the methods were evaluated using linear regression and Bland–Altman analyses, respectively. Mean prostate volume was 16.57 ± 11.20 cm³ with three-dimensional segmentation and 16.35 ± 14.63 cm³ with the ellipsoid formula. No significant difference was found between the methods (P = 0.945). A positive linear association was observed between segmentation- and ellipsoid-derived volumes (R = 0.970; R² = 0.942; P < 0.001). Bland–Altman analysis showed a mean difference of −0.224 cm³, with 95% limits of agreement ranging from −9.291 to 8.843 cm³. Although the ellipsoid formula produced a group mean close to that obtained by three-dimensional segmentation, the relatively wide limits of agreement indicated variability between the methods at the individual-case level. These preliminary findings should be confirmed in larger canine populations before the methods are considered interchangeable.

Keywords

computed tomography, dog, ellipsoid formula, prostate, three-dimensional segmentation, volumetry

Thanks

The author thanks the staff of the Veteriner Radyoloji Merkezi for their assistance in retrieving the archived computed tomography images and clinical records used in this study.

References

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APA
Nizam, M. Y. (2026). Comparison of CT-Derived Prostate Volume Measurements Using Three-Dimensional Segmentation and the Ellipsoid Formula in Intact Male Dogs. Journal of Anatolian Environmental and Animal Sciences, 2026. https://doi.org/10.35229/jaes.2018505
AMA
1.Nizam MY. Comparison of CT-Derived Prostate Volume Measurements Using Three-Dimensional Segmentation and the Ellipsoid Formula in Intact Male Dogs. JAES. 2026;(2026). doi:10.35229/jaes.2018505
Chicago
Nizam, Mustafa Yiğit. 2026. “Comparison of CT-Derived Prostate Volume Measurements Using Three-Dimensional Segmentation and the Ellipsoid Formula in Intact Male Dogs”. Journal of Anatolian Environmental and Animal Sciences, nos. 2026. https://doi.org/10.35229/jaes.2018505.
EndNote
Nizam MY (October 1, 2026) Comparison of CT-Derived Prostate Volume Measurements Using Three-Dimensional Segmentation and the Ellipsoid Formula in Intact Male Dogs. Journal of Anatolian Environmental and Animal Sciences 2026
IEEE
[1]M. Y. Nizam, “Comparison of CT-Derived Prostate Volume Measurements Using Three-Dimensional Segmentation and the Ellipsoid Formula in Intact Male Dogs”, JAES, no. 2026, Oct. 2026, doi: 10.35229/jaes.2018505.
ISNAD
Nizam, Mustafa Yiğit. “Comparison of CT-Derived Prostate Volume Measurements Using Three-Dimensional Segmentation and the Ellipsoid Formula in Intact Male Dogs”. Journal of Anatolian Environmental and Animal Sciences. 2026 (October 1, 2026). https://doi.org/10.35229/jaes.2018505.
JAMA
1.Nizam MY. Comparison of CT-Derived Prostate Volume Measurements Using Three-Dimensional Segmentation and the Ellipsoid Formula in Intact Male Dogs. JAES. 2026. doi:10.35229/jaes.2018505.
MLA
Nizam, Mustafa Yiğit. “Comparison of CT-Derived Prostate Volume Measurements Using Three-Dimensional Segmentation and the Ellipsoid Formula in Intact Male Dogs”. Journal of Anatolian Environmental and Animal Sciences, no. 2026, Oct. 2026, doi:10.35229/jaes.2018505.
Vancouver
1.Mustafa Yiğit Nizam. Comparison of CT-Derived Prostate Volume Measurements Using Three-Dimensional Segmentation and the Ellipsoid Formula in Intact Male Dogs. JAES. 2026 Oct. 1;(2026). doi:10.35229/jaes.2018505