Fig. 2. US images illustrating transrectal US vas-tracing technique of identifying retained abdominal testis.
vein, helps to properly identify the retained testis (Fig. 1, A–C).5 If the retained testis is not found in the inguinal
region, suspect complete or incomplete abdominal cryptorchidism. In such cases, perform transab- dominal or transrectal US exam, or both. While transabdominal US is noninvasive, the authors pre- fer transrectal US. Various regions of the abdomen
are systematically scanned using transabdominal ultrasonography to search for the retained abdomi- nal testis, which is often time-consuming. Trans- rectal US, by contrast, allows tracing the vas deferens all the way to the testis, which signifi- cantly shortens the examination time required. In more challenging cases, use a combination of both techniques.
Fig. 3. Series of US images (from A to D) illustrating the transrectal US vas-tracing technique of identifying the retained abdominal testis that shows all anatomical elements of the reproductive tract that can be visualized during this procedure: ampulla, narrow part of the vas deferens, epididymal tail, epididymal body, blood vessels, testis. Note that not all anatomical details are visualized during each examination.
