Testicular torsion occurring beyond the neonatal period is related to the abnormal suspension of the testicles within the tunica vaginalis, sometimes referred to as a “bell clapper” deformity, which allows the testicles to rotate on the spermatic cord. 360 degrees of torsion will occlude venous return, but arterial flow may persist, a situation roughly analogous to that of compartment syndrome in the limbs. Patients present with intense pain of acute onset.

TORSION – SONOGRAPIC FINDINGS
An enlarged, in homogenously hypoechoic testicle
Lack of flow on Doppler interrogation
Peritesticular hyperemia
Reactive hydrocele
TORSION - DISCRIMINATORS
In epididymo-orchitis, the echo pattern may be similar to that of torsion, but there will be increased epididymal and testicular flow. The onset of symptoms is usually insidious.
Completed testicular infarction may usually be distinguished by history. The testicle should not be enlarged.