Abstract: Men or boys, who present with acute scrotal pain without prior trauma or a known mass, most commonly suffer from torsion of the spermatic cord; epididymitis or epididymoorchitis; or torsion of the testicular appendages. Less common causes of pain include a strangulated hernia, segmental testicular infarction, or a previously undiagnosed testicular tumor. Ultrasound is the study of choice to distinguish these disorders; it has supplanted Tc-99 m scrotal scintigraphy for the diagnosis of spermatic cord torsion. MRI should be used in a problem solving role if the ultrasound examination is inconclusive. The ACR Appropriateness Criteria® are evidence-based guidelines for specific clinical conditions that are reviewed every two years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.