Small Parts Scrotal Ultrasound ScanCoach™

Supine with the scrotum supported on a towel draped between the thighs. The penis should be retracted superiorly and taped to the abdomen. This position stabilizes the scrotum and allows bilateral comparison. Use copious warm gel to minimize patient discomfort.

Begin with a split-screen transverse view of both testes simultaneously to compare size, echogenicity, and vascularity side-by-side. This bilateral comparison is essential for detecting subtle asymmetry in echogenicity or blood flow, particularly in torsion.

Confirm presence of two testes; compare size, echogenicity, and vascularity bilaterally; identify any gross asymmetry in testicular size (>20% difference is significant); assess the epididymis bilaterally; identify any hydrocele, hematocele, or pyocele.

Always perform a bilateral comparison scan first, before focusing on the symptomatic side. In torsion, the affected testis may appear normal in echogenicity early — the key finding is absent or markedly reduced blood flow on color Doppler compared to the contralateral testis. A unilateral finding is more significant than an absolute measurement.

Normal testicular volume: 12–20 mL (length × width × depth × 0.71). Testicular atrophy is defined as volume <12 mL or >20% smaller than the contralateral testis. Prepubertal testes are smaller (1–2 mL) and have less vascularity — do not mistake reduced flow for torsion in a child.