Utility of cine clips of the spermatic cord in the diagnosis of testicular torsion in the pediatric population.

Background: Indirect evidence of testicular torsion, namely lack of blood flow, has been a mainstay in the imaging diagnosis of testicular torsion. Recently, attention has been given to the etiology of testicular torsion, namely the twisted vascular pedicle. However, no study to date has demonstrated the diagnostic yield of inclusion of cine clips of the spermatic cord in identifying this twist.

Objective: This study seeks to demonstrate whether the inclusion of cine clips of the spermatic cord impacts the diagnostic performance of ultrasound in diagnosing testicular torsion.

Materials and methods: This study employed a multi-reader multi-case complete and balanced block cross-over design to assess the diagnostic performance of ultrasound, specifically the impact of cine clips of the spermatic cord. From 1/1/2015 to 12/31/2017, ultrasounds of 156 patients presenting with acute onset of unilateral scrotal pain were reviewed by five pediatric radiologists. Within this data set were 52 cases of surgically confirmed testicular torsion, 52 cases that were abnormal but without testicular torsion, and 52 normal exams. The data set was reviewed twice; initially, static images alone were reviewed. After a period of at least 2 weeks, the data set was again reviewed with the inclusion of cine clips of the spermatic cord. A questionnaire was answered after each review that elicited the radiologist's final diagnosis. Sensitivity and specificity between imaging features were estimated using generalized linear mixed modeling with the GLIMMIX procedure.

Results: With the inclusion of cine clips of the spermatic cord, the sensitivity in diagnosing testicular torsion increased from 88.8% (95%CI 78.1-94.6%) to 98.5% (95%CI 96.0-99.5%) (P < 0.0001) with no statistically significant change to specificity 98.4% (95%CI 95.9-99.4%) to 97.0% (95%CI 94.9-98.3%) (P = 0.61).

Conclusion: This study provides compelling evidence to consider cine clips of the spermatic cord as part of a standard ultrasound approach for the work-up of testicular pain due to the nearly 10% increase in sensitivity in diagnosing testicular torsion with their inclusion.