Ultrasound images in acute scrotum--Torsion Testis

Diagnostic imaging, particularly Doppler ultrasonography, plays an important role in the assessment of the patient with acute scrotal pain and swelling.

                  The affected testes was removed and found to be gangrenous

Testicular torsion, also termed torsion of the spermatic cord, is a relatively common and potentially devastating acute condition due to obstruction of the arterial blood supply to the testis.Fortunately, this entity is relatively well known, and it usually occurs with enough discomfort to lead to its diagnosis and subsequent testicular salvage
. However, atypical presentations of testicular torsion, delayed recognition of the condition, and its confusion with other causes of acute scrotum can potentially delay diagnosis and lead to testicular necrosis necessitating orchiectomy

The -"Whirl pool sign"-or-"snail sign" is also seen in the testes, caused by swollen testes  and twisted, bulky spermatic cord .
These ultrasound images suggest torsion of the Right testes.

The whirl pool sign-"snail sign" is also seen in twisted, bulky spermatic cord
(body and head of snail). 

ultrasonography with color and power Doppler imaging has emerged as the primary imaging modality for the diagnosis of testicular torsion.It not only helps in corroborating the diagnosis by alteration of testicular echotexture but also provides valuable information on vascular perfusion of the testis. In addition, sonographic findings frequently allow other diagnoses to be made in those patients presenting with an acute scrotum who do not have torsion..

Prior to the development of high resolution, real-time ultrasonography coupled with sensitive color Doppler, nuclear scintigraphy was the mainstay of tests available to evaluate the acute scrotum. 

Given associated radiation, less widespread availability, limited ancillary information, and the accuracy of color Doppler imaging, scrotal scintigraphy is no longer used as frequently

..

Information about the role of MRI in the diagnosis of torsion is limited. 

Although MRI is likely to be highly sensitive..

 However, with its limited availability, particularly at night, and its cost, MRI is unlikely to become a front-line examination for the patient presenting with acute scrotal pain.

Limitations of techniques

Color Doppler ultrasonography is highly
 operator dependent.

 In the diagnosis of testicular torsion, gray-scale findings are combined with dynamic flow information. Inaccurate results may be obtained in the prepubertal patient with small testicular volume or in cases with multiple imaging and Doppler artifacts. Such imaging artifacts may result from inappropriate gain settings and the non-use of slow-flow techniques..