US in the assessment of acute scrotum

Abstract

Background: The acute scrotum is a medical emergency . The acute scrotum is defined as scrotal pain, swelling, and redness of acute onset. Scrotal abnormalities can be divided into three groups , which are extra-testicular lesion, intra-testicular lesion and trauma. This is a retrospective analysis of 164 ultrasound examination performed in patient arriving in the emergency room for scrotal pain.The objective of this article is to familiarize the reader with the US features of the most common and some of the least common scrotal lesions.

Methods: Between January 2008 and January 2010, 164 patients aged few month and older with scrotal symptoms, who underwent scrotal ultrasonography (US), were retrospectively reviewed. The clinical presentation, outcome, and US results were analyzed. The presentation symptoms including scrotal pain, painless scrotal mass or swelling, and trauma.

Results: Of 164 patients, 125 (76%) presented with scrotal pain, 31 (19%) had painless scrotal mass or swelling and 8 (5%) had trauma. Of the 125 patients with scrotal pain, 72 had infection,10 had testicular torsion, 8 had testicular trauma, 18 had varicocele, 20 had hydrocele, 5 had cryptorchidism, 5 had scrotal sac and groin metastases, and 2 had unremarkable results. In the 8 patients who had history of scrotal trauma, US detected testicular rupture in 1 patients, scrotal haematomas in 2 patients .Of the 19 patients who presented with painless scrotal mass or swelling, 1 6 had extra-testicular lesions and 3 had intra-testicular lesions. All the extra-testicular lesions were benign. Of the 3 intra-testicular lesions, one was due to tuberculosis epididymo-orchitis, one was non-Hodgkin's lymphoma, and one was metastasis from liposarcoma

Conclusions: US provides excellent anatomic detail; when color Doppler and Power Doppler imaging are added, testicular perfusion can be assessed.

Figure 1

(a,b,c,d) Gray-scale and Colour Doppler of epididymis US findings of these lesions, including enlarged epididymis and/or testis with heterogeneous echogenicity, are overlapping but CDUS findings are different (a). The inflamed epididymis and testis have increased blood flow whereas testicular torsion has decreased blood flow(b). The epididymal head is the most affected region, and reactive hydrocele and wall thickening are frequently present(c). Increased size and, depending on the time of evolution, decreased, increased, or heterogeneous echogenicity of the affected organ are usually observed (d).

Figure 2

(a,b) Gray-scale and Colour Doppler of testicular torsion. In the early phases of torsion (1–3 hours), testicular echogenicity appears normal. With progression, enlargement of the affected testis and increased or heterogeneous echogenicity are common findings. A definitive diagnosis of complete testicular torsion is made when blood flow is visualized on the normal side but is absent on the affected side .Incomplete torsion refers to cord twisting of less than 360°, in which some arterial flow persists in the affected testis .

Figure 3

Gray scale and Colour Doppler of testicular trauma. In this type of injury, US images also demonstrate poorly defined testicular margins and heterogeneous echotexture, with focal hyperechoic or hypoechoic areas in the testicular parenchyma corresponding to areas of hemorrhage or infarction . Color and duplex Doppler images may show decreased flow or no flow.