Functional Imaging of Testicular Torsion

This article discusses the current clinical role and scope of functional radionuclide imaging using testicular perfusion scintigraphy with ^99mTc-pertechnetate in patients presenting with an acute hemiscrotum for an early and reliable diagnosis of testicular torsion. The technique of testicular perfusion scintigraphy is described, and the characteristic findings are detailed with examples. The imaging characteristics of the various phases of testicular torsion and its differentiation from epididymitis and/or epididymo-orchitis and the other related conditions presenting as an acute hemiscrotum are detailed. In some cases, further evaluation by SPECT imaging increases the clarity and accuracy of diagnosis and, on occasion, hybrid SPECT/CT in selected complicated cases improves the diagnostic yield of the perfusion scintigraphy. Ultrasonographic and color Doppler findings are described concurrently with the scintigraphic findings. The several case examples presented demonstrate the additional clinical benefit of complementing functional and structural imaging for improving the sensitivity, specificity and accuracy of testicular imaging in the diagnosis.