Increased thickness (anterior-posterior diameter – APD), mono- or bilateral (>14 mm);

Asymmetry (>2.5 mm) between the two SVs, even with normal APD (7–14 mm);

Reduced APD, mono- or bilateral (<7 mm)

Thickened glandular epithelium or with calcification/s;

The presence of polycyclic areas separated by hyperechoic septa (honeycomb shaped) in one or both SVs (Fig. 25.3) [3, 4].

Glandular bottom-body ratio inferior to 1 or superior to 2.5;

APD of the body unmodified after ejaculation. Currently there are no literature data about the description of the SV dilation with a volumetric cut-off. Nevertheless, an elevated volume after ejaculation is highly associated with SV anomalies, with large prostate or with the presence of median cysts which might cause obstruction of the ejaculatory ducts. A reduced volume of the SV is defined as hypoplasia, and it principally refers to congenital forms with small SV. Nevertheless, acquired forms, associated with testosterone deficiency, exist. Hypoplasia is defined such by some authors when the APD VS is <5 or <7 mm, whereas other authors suggest to refer to the longitudinal diameter (normal if >25 mm, hypoplastic if 16–25 mm, and atrophic if <16 mm).

Bilateral agenesis;

Monolateral agenesis (Fig. 25.4);