IS Case 170: Testicular torsion
Imaging Sciences URMC 2008
Publication Date: 2009-05-21
Patient is an 14-year-old boy with a 12 hour history of right scrotal pain.
Testicular torsion is a twisting of the spermatic cord which can strangulate blood flow to and from the testicle. Although it may occur at any age, it most commonly affects young males, approximately 1 in 4000 under the age of 25. Intravaginal torsion is the most common subtype, accounting for 90% of cases, and typically occurring between the ages of 12 and 18. This type is due to an abnormal testicular suspension known as the bell-clapper deformity and occurs within the tunica vaginalis, hence the term intra-vaginal torsion.
Testicular torsion is one of many diagnostic considerations which exist for acute scrotal pain. The differential also includes epididymo-orchitis, torsion of the testicular appendages, and trauma. Distinguishing among these urgently is necessary given the serious morbidity of testicular ischemia and for treatment planning. When a testicle torses, it has salvage rates near 100% within the first 6 hours, 70% between 6 and 12 hours, and 20% between 12 and 24 hours. Salvage rates after 24 hours are less than 10%.
In addition to patient history and physical exam, sonography has become a valuable tool in assisting the clinician to diagnose the acute scrotum. Grayscale evaluation of partial torsion usually appears normal. Color flow and spectral Doppler evaluation of torsion may demonstrate: (1) Absent arterial and venous flow, (2) increased resistive index on the affected side (diminished or reversed diastolic flow), or (3) decreased flow velocity, low amplitude on symptomatic side.
- Lin EP, Bhatt S, Rubens DJ, Dogra VS. Testicular torsion: twists and turns. Semin Ultrasound CT MR. 2007 Aug;28(4):317-28. [PMID: 17874655]