The diagnostic value of ultrasound in pediatric testicular torsion with preserved flow

Abstract

BackgroundTesticular torsion is the reduction of blood flow to the testis after spermatic cord torsion. For patients, the diagnosis of testicular torsion is controversial and complicated by the fact that ultrasound blood flow signals are not significantly reduced in comparison to the unaffected, healthy, testis, despite persistent symptoms on the affected side. Our study aims to investigate the diagnostic characteristics of high-resolution ultrasonography (US) in pediatric testicular torsion with the preserved flow to increase diagnostic accuracy.MethodsSeven pediatric patients aged 49 days to 15 years old, with the preserved blood flow, but surgically diagnosed as testicular torsion, from October 2017 to August 2019, were retrospectively included in the study. The imaging manifestations of high-frequency ultrasonography were evaluated.ResultsAll cases had preserved testicular blood flow, but the surgical findings showed various degrees of twist, from 90 to 540 degrees. Preoperative ultrasound showed spermatic cord distortion in all cases, and testicular long axis tilting in four cases (4/7 = 57.1%).ConclusionIn some testicular torsion cases, Color Doppler may show normal or increased blood flow signals in the testis. We should further observe the morphology and position of the testes and epididymides, the echo of the testicular parenchyma, and, especially evaluate the “whirlpool sign” in the spermatic cord, to avoid missing testicular torsion with blood flow signals.

Solitary whirlpool sign demonstrated with testicular torsion on ultrasonography

“…In the ultrasound diagnosis of TT, findings of decreased testicular blood flow on color Doppler are generally considered useful, with a reported sensitivity of 86% and specificity of 100% 2 . However, there are some reports of testicular torsion in which blood flow can be confirmed, and the risk of a false negative diagnosis based solely on the presence of blood flow has been reported 3 . Doppler may also misidentify artifacts as blood flow, and there are problems such as difficulty in obtaining testicular blood flow signals in young children.…”

“…However, diagnostic skill that accurately delineates the whirlpool sign is needed. The whirlpool sign has been shown to be depicted with torsion of more than 90 degrees 3 . Recently, it has also been reported that superb microvascular imaging can depict blood flow more clearly than power Doppler in testicular torsion 5…”

“…2 However, there are some reports of testicular torsion in which blood flow can be confirmed, and the risk of a false negative diagnosis based solely on the presence of blood flow has been reported. 3 Doppler may also misidentify artifacts as blood flow, and there are problems such as difficulty in obtaining testicular blood flow signals in young children. On the other hand, the whirlpool sign has a sensitivity and specificity of nearly 100% and is considered the most useful ultrasound finding in the diagnosis of TT.…”

“…The whirlpool sign has been shown to be depicted with torsion of more than 90 degrees. 3 Recently, it has also been reported that superb microvascular imaging can depict blood flow more clearly than power Doppler in testicular torsion. 5 In the present case, scrotal pain had improved at the time of the outpatient visit and we thought that blood flow in the testis was visible due to the intermittent nature of the TT.…”