Testicular atrophy after mumps orchitis: ultrasonographic findings

PURPOSE: The purpose of this study was to describe the ultrasonographic findings of testicular atrophy after mumps orchitis. METHODS: We retrospectively reviewed the case files of eight patients (14 to 24 years old; mean, 17 years) with mumps orchitis and testicular atrophy who were treated between January 2011 and September 2017. On gray-scale and color Doppler, the ultrasonographic features of volume, shape, echogenicity, and degree of blood flow in the testes were analyzed as part of both initial and follow-up ultrasonography. The duration between the initial diagnosis of mumps orchitis and the ultrasonographic diagnosis of testicular atrophy after mumps orchitis ranged from 25 to 230 days (mean, 95.9 days). RESULTS: Of the eight patients with testicular atrophy after mumps orchitis, the testes were affected unilaterally in seven patients (6 right-sided and 1 left-sided) and bilaterally in one patient. The affected testes (n=9) were 23%-55% (mean, 44.7%) smaller in volume (mean, 6.3±2.0 mL) than the contralateral normal testes (n=7) (mean, 10.8±2.3 mL) on follow-up ultrasonography (P=0.001). The shape of the atrophic testes was oblong in seven cases and elliptical in two cases. The atrophic testes were either heterogeneously hypoechoic with multiple hyperechoic islands (n=7) or heterogeneously hyperechoic (n=2). On follow-up color Doppler ultrasonography, the degree of vascularity of the atrophic testis was either similar to (n=3) or lower than (n=6) that of the contralateral testis. CONCLUSION: On ultrasonography, atrophic testes after mumps orchitis tended to exhibit an oblong shape, heterogeneous low echogenicity with multiple hyperechoic islands, and decreased vascularity.