Testicular Volume Assessment
Your testicle with a length of 3.5 cm and volume of 13.1 ml is borderline-small but NOT definitively atrophied, as the established threshold for testicular atrophy is <12 ml. 1
Understanding the Volume Threshold
Testicular volumes less than 12 ml are definitively considered atrophic and associated with significant pathology, including impaired spermatogenesis and increased risk of intratubular germ cell neoplasia. 1, 2
Your volume of 13.1 ml falls just above this threshold, placing you in the borderline-small category (12-15 ml range) rather than definitively atrophic. 1
The 12 ml cutoff is well-established across multiple international guidelines as the lower limit distinguishing normal from atrophic testes. 3, 1
Clinical Significance of Your Measurement
While not technically atrophied, your testicular volume warrants clinical correlation based on specific risk factors:
High-Risk Scenarios Requiring Further Evaluation:
Age under 30-40 years with history of cryptorchidism (undescended testicle): This combination carries approximately 30-34% risk of intratubular germ cell neoplasia in the contralateral testis if testicular cancer develops. 3, 1
Presence of testicular cancer: If you have or develop testicular cancer, contralateral biopsy is strongly indicated given the elevated cancer risk at volumes near 12 ml. 3, 1
Infertility concerns: Volumes at this threshold warrant semen analysis and hormonal evaluation (FSH, LH, testosterone), as testicular volume strongly correlates with total sperm count and sperm concentration. 1
Important Caveats:
If there is a size discrepancy between your testes greater than 2 ml or 20%, further evaluation including ultrasound is warranted to exclude pathology. 1
Measurement accuracy matters: Technical errors in ultrasound caliper placement can lead to incorrect volume calculations. If this measurement seems inconsistent with your clinical picture, request a repeat scrotal ultrasound with explicit attention to proper measurement technique. 1
Recommended Next Steps
Obtain detailed history focusing on:
- History of cryptorchidism (undescended testicle). 1
- Infertility concerns or difficulty conceiving. 1
- Family history of testicular cancer. 1
- Prior testicular pathology or trauma. 1
Consider hormonal evaluation if:
- You have infertility concerns or abnormal semen analysis. 1, 4
- You are experiencing symptoms of low testosterone. 4
Refer for testicular biopsy if high-risk features present:
- Age <30 years with history of cryptorchidism. 1
- Presence of testicular cancer (for contralateral biopsy). 1
- Infertility with bilateral small testes. 1
Teach yourself testicular self-examination given the slightly increased cancer risk with smaller volumes, particularly if you have other risk factors. 1, 4