Can a Radiologist Diagnose Testicular Atrophy?
Yes, a radiologist can and should diagnose testicular atrophy using ultrasound, as it is a critical finding with significant clinical implications including increased cancer risk and fertility concerns. 1
Diagnostic Criteria and Measurement
- Testicular atrophy is definitively diagnosed when testicular volume measures less than 12 mL, which is the established clinical threshold used in practice. 2, 1, 3
- Radiologists calculate testicular volume using the formula π/6 × length × height × width from ultrasound measurements. 3, 4
- The contralateral testis serves as an internal control to assess for true pathologic asymmetry, making bilateral measurement essential. 1
Clinical Significance Requiring Radiologist Documentation
- Men with testicular atrophy have an 11.9-fold higher risk of testicular cancer, particularly in the setting of cryptorchidism, family history, or prior cancer. 1, 3
- Marked atrophy in the setting of cryptorchid testis warrants consideration of contralateral testicular biopsy according to NCCN guidelines. 2, 1
- Testicular atrophy is a critical factor in evaluating male fertility, especially in men with oligozoospermia or azoospermia. 1, 3
Ultrasound Findings of Testicular Atrophy
- Volume reduction is the primary diagnostic criterion, with atrophic testes measuring significantly smaller than the contralateral normal testis (typically 23%-55% reduction). 5
- Heterogeneous or mottled echotexture on grayscale ultrasound corresponds to extensive tubular sclerosis and atrophy on histology. 6
- Atrophic testes may demonstrate heterogeneously hypoechoic appearance with multiple hyperechoic islands or heterogeneously hyperechoic patterns. 5
- Color Doppler evaluation may show decreased vascularity compared to the contralateral testis, though perfusion can appear similar in some cases. 5
Radiologist's Role and Reporting Responsibilities
- The radiologist should actively measure and document testicular volumes bilaterally, calculate the percentage difference, and explicitly state when atrophy is present. 1, 3
- Ultrasound is the established first-line imaging modality for scrotal disease and can diagnose testicular atrophy promptly and with high accuracy. 2
- The radiologist must document suspicious associated findings such as hypoechoic masses or macrocalcifications that may accompany atrophy, as these require further evaluation with tumor markers. 1
- Doppler evaluation should be performed even when grayscale appearance seems normal, as perfusion abnormalities may indicate underlying pathology. 1
Clinical Contexts Where Atrophy Diagnosis is Critical
- Risk assessment for testicular cancer: Atrophy should always be documented when present in patients with cryptorchidism, family history of testicular cancer, or prior contralateral cancer. 1, 3
- Infertility evaluation: Testicular volume measured by ultrasound correlates significantly with testicular function and spermatogenesis. 7
- Post-mumps orchitis monitoring: Atrophy develops 25-230 days after mumps orchitis and requires documentation for prognostic purposes. 5
- Cryptorchidism assessment: Three-dimensional ultrasound with testicular atrophy index objectively reflects testicular volume and guides surgical timing. 8