Diagnostic imaging in cryptorchidism: utility, indications, and effectiveness.

BACKGROUND: Cryptorchidism (undescended testis) is the most common genitourinary anomaly in male infants.

METHODS: We reviewed the available literature on the diagnostic performance of ultrasound, computed tomography, and magnetic resonance imaging (MRI) in localizing undescended testes.

RESULTS: Ultrasound is the most heavily used imaging modality to evaluate undescended testes. Ultrasound has variable ability to detect palpable testes and has an estimated sensitivity and specificity of 45% and 78%, respectively, to accurately localize nonpalpable testes. Given the poor ability to localize nonpalpable testes, ultrasound has no role in the routine evaluation of boys with cryptorchidism. Magnetic resonance imaging has greater sensitivity and specificity but is expensive, not universally available, and often requires sedation for effective studies of pediatric patients. Diagnostic laparoscopy has nearly 100% sensitivity and specificity for localizing nonpalpable testes and allows for concurrent surgical correction.

CONCLUSIONS: Although diagnostic imaging does not have a role in the routine evaluation of boys with cryptorchidism, there are clinical scenarios in which imaging is necessary. Children with ambiguous genitalia or hypospadias and undescended testes should have ultrasound evaluation to detect the presence of müllerian structures.