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Comparison of testicular volume differential calculations in adolescents with varicoceles
Matthew S Christman1, Stephen A Zderic2, Thomas F Kolon2
1Department of Urology, Naval Medical Center San Diego, 34800 Bob Wilson Drive, San Diego, CA 92134, USA.
Purpose:
We aimed to develop a conversion formula between different calculations for testicular volume asymmetry.
Materials And Methods:
Male adolescents with varicoceles who underwent scrotal ultrasound were studied. Two formulas were analyzed: (1) testicular volume differential, TVDiff = (RTV - LTV)/(TTV), and (2) atrophy index, AI = (RTV - LTV)/(RTV). RTV, LTV, and TTV represent the right, left, and total testicular volume. Through transformations and regression a conversion formula between the calculations was derived.
Results:
Based on 248 ultrasounds, a clear relationship between the two formulas was demonstrated: AI = ln[(1.97 × TVDiff) + 1], (p < 0.0001).
Conclusions:
Differential testicular volumes can easily be converted from one formula to another with near-perfect accuracy. The formulas are essentially identical and interchangeable.
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