IMPORTANT: We currently have a number of bugs related to image cropping and are actively trying to resolve them. In the meantime, we have disabled cropping. Apologies for any inconvenience. Stay informed: radiopaedia.org/chat

Undescended testis

Case contributed by Ian Bickle
Diagnosis certain

Presentation

One palpable testis in the scrotum.

Patient Data

Age: 20 years
Gender: Male
mri

Prior ultrasound in an alternative institution.

The normal left testis is identified lying within the left side of the scrotal sac.  The undescended smaller right testis is intraperitoneal in location, lying medial to the right external iliac vessels.

Case Discussion

The undescended testis (cryptorchidism) may be intra-abdominal or what is termed canalicular in nature. Canilicular describes those testes along the normal pathway of descent, that are both outside of the abdominal cavity, but not in the scrotum.

Ultrasound is the first line investigation, as a large percentage of undescended testes (80%) are within the inguinal canal and therefore can be identified.

MRI has a role, especially in identifying those within the abdomen, when ultrasound has not a canilicular type. It is usually of greater use in the late presenter, that is older children or young adults, due the difficulties in cooperation with small children and infants.

The undescended testis is also often smaller, as in this case (3.5 cm vs 2.4 cm).

T1 and T2 weighted axial and coronal sequences, especially with a small field of view (FOV) are advisable as well as diffusion weighted imaging. The testis is typically low signal on T1 and high signal on T2. The normal testis exhibits intense diffusion restriction, and these sequences can aid confident identification.

How to use cases

You can use Radiopaedia cases in a variety of ways to help you learn and teach.

Creating your own cases is easy.

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.