Trauma. A direct blow to the scrotal sac can cause significant testicular parenchymal injury or hemorrhage and can definitely alter the normal homogeneous appearance of the testicle. Hematomas in the epididymis or scrotal wall may have variable sonographic appearances. Just like hematomas in other parts of the body, their appearance may vary depending upon the age of the hematoma. At first the hematoma will be hypoechoic as the red blood cells fill the space; as the hematoma ages, its appearance becomes more echogenic as clot begins to form within the bleed.


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