Emergency Ultrasound > Top 10 Pathology > Testicular Torsion

Testicular Torsion

Testicular torsion is one of the most common indications for scrotal ultrasound as it requires accurate and prompt diagnosis in order to allow salvage of the hemodynamically compromised organ. It usually occurs in young teenage boys and presents as acute painful swelling. The differential diagnosis for acute painful testicular swelling include testicular torsion, torsion of a testicular appendage, epididymoorchitis, trauma and neoplasm Torsion is caused in most cases by a congenital abnormality related to high insertion of the tunica vaginalis and a "bell clapper" deformity. The risk of infarction of the testicle varies with the degree of torsion and studies have shown that torsion of 720 obstructs arterial blood flow and may cause testicular infarction within two hours. It is imperative to scan the patient within the shortest period of time and to consult the Urology clinical team. Doppler interrogation shows no flow or in cases of lesser degree of torsion, decreased flow with low peak systolic velocity (Fig 4a). If the findings from the study are doubtful and no definite answer for the symptoms is found, the study should be repeated when symptoms recur and again, the Urology clinical team should be consulted.

3a1.jpg 3b.jpg

Fig 4 a. Torsion, view of epidydimis, b. Torsion, gross pathology


Fig 4 c. Side-by-side both testes with & without flow.

The incidence of torsion is approximately 1 in 160 males by 25 years of age and salvage is much higher when treatment is instituted within 6 hours of the onset of symptoms. Severity of torsion depends on the degree of twisting. Torsion has been shown to occur at 450, but the range lies between 180 and 720. Collateral blood flow is not adequate to maintain testicular viability after a significant degree of torsion, 450 degrees, has occurred. Venous congestion leads to arterial occlusion which leads to ischemia and infarction (Fig 4b). The sonographic study of torsion must include gray scale and color Doppler images in order to demonstrate alteration of testicular echogenicity, scrotal wall edema, hydrocele and the presence or absence of symmetric testicular blood flow (Fig 4c). Spontaneous detorsion can occur and may still show sonographic abnormal findings where there is presence of blood flow but with abnormally low peak systolic velocity. The most important clinical finding of detorsion is the spontaneous improvement in patient's symptomatology. Again, a repeat scan if symptoms recur is indicated as the symptoms of torsion may repeat later.

© Copyright Rector and Visitors of the University of Virginia 2013