Diagnostic imaging for pediatric scrotal disorders.

Classification of pediatric scrotal disorders into three typical clinical manifestations--acute scrotal disorders, scrotal masses, and cryptorchidism--provides a practical basis for evaluation with the most commonly used modalities--sonography, scintigraphy, and magnetic resonance (MR) imaging. Acute scrotal disorders of children include acute epididymitis, torsion of an appendix testis or appendix epididymis, and torsion of the spermatic cord. Either scintigraphy or sonography may be used as the first imaging study, and both can aid in distinguishing among the disorders to different degrees. However, sonography is becoming the preferred modality, primarily because of the superior anatomic detail provided. Scrotal masses are also best depicted with sonography, although MR imaging can occasionally be a useful adjunctive modality. In cases of suspected cryptorchidism with equivocal clinical findings, both sonography and MR imaging may be useful, although sonography is usually the initial study. Knowledge of characteristic imaging appearances, as well as benefits and limitations of the available modalities, enables appropriate, expeditious radiologic evaluation of pediatric scrotal disorders.