Testicular volume measurement: comparison of ultrasonography, orchidometry, and water displacement

Urology. 2007 Jan;69(1):152-7. doi: 10.1016/j.urology.2006.09.012.


Objectives: To determine the accuracy of orchidometry and ultrasonography for measuring the testicular volume by comparing the resultant measurements with the actual testicular volume in humans.

Methods: The testicular volume of 40 testes from 20 patients with prostate cancer (mean age +/- SD 74.5 +/- 7.5 years) was measured using the Prader orchidometer and ultrasonography before therapeutic bilateral orchiectomy. The ultrasound measurements of testicular volume were calculated using three formulas: length (L) x width (W) x height (H) x 0.52, L x W2 x 0.52, and L x W x H x 0.71. The actual testicular volumes were determined by water displacement of the surgical specimen.

Results: The mean actual testicular volume of the 40 testes was 9.3 cm3 (range 2.5 to 23.0). A strong correlation was found between the testicular volume calculated by the three ultrasound formulas and the actual volume (r = 0.910 to 0.965, P <0.0001) and was stronger than the correlation with the Prader orchidometer (r = 0.818, P <0.0001). The smallest mean difference from the actual testicular volume was observed with the formula L x W x H x 0.71, which overestimated the actual volume by 0.80 cm3 (7.42%). The measurements using the Prader orchidometer correlated with the actual testicular volume and with the testicular volume calculated using the three ultrasound formulas (r = 0.801 to 0.816, P <0.0001). However, the orchidometer measurements had the largest mean difference from the actual testicular volume (6.68 cm3, 81.7%).

Conclusions: The results of this study have shown that measuring the testicular volume by ultrasonography is more accurate than by the Prader orchidometer, and the formula L x W x H x 0.71 was the most accurate for calculating the testicular volume.

Publication types

  • Comparative Study

MeSH terms

  • Aged
  • Anthropometry
  • Humans
  • Male
  • Orchiectomy
  • Organ Size
  • Reproducibility of Results
  • Testis / anatomy & histology*
  • Testis / diagnostic imaging*
  • Ultrasonography
  • Water


  • Water