A number of testicular diseases may present as diffuse abnormalities of the testis. In general, these may be separated into inflammatory and neoplastic groups.

Diffuse neoplastic disease of the testicle is associated with moderate to marked enlargement, globular shape, lobulated contour, and heterogenous texture of the testes. The epididymis and scrotal skin are usually normal.

In diffuse inflammatory disease, the testis is mild to moderately enlarged, the oval shape and smooth contour are often preserved, and the texture is generally homogeneous with the epididymis enlarged and scrotal skin thickening present. Despite these differences, diffuse testicular neoplasm may mimic infection and vice versa.

Color flow Doppler ultrasound can show a diffusely abnormal testis. This may be useful in separating inflammatory from neoplastic disease in confusing cases. With diffuse neoplastic infiltration of the testicle, you may see increased vascularity on color flow or Doppler ultrasound. The normal vascular architecture is usually distorted or completely replaced by the neoplastic tissue. Diffuse inflammatory changes demonstrate an increased testicular flow in most cases, with this increased vascularity present in the normal vascular distribution.

The most common inflammatory process which would produce a diffuse vascular pattern in the testicle is epididymo-orchitis. In acute torsion of the testis, diminished or absent flow will be demonstrated within these vessels. An abrupt cessation of flow may be noted in the spermatic cord.