Canal of Nuck Abnormalities.

Canal of Nuck abnormalities are underrecognized causes of labial masses with potential adverse outcomes. The 2 main categories of canal of Nuck abnormalities are hernias and hydroceles. There are 3 types of canal of Nuck hydroceles: communicating, encysted, and bilocular. Canal of Nuck hernia contents vary, but those containing ovaries need urgent medical attention because of an increased risk of ischemia. Ultrasound can establish a definite diagnosis in all cases. This article reviews the embryologic characteristics, anatomy, pathologic characteristics, and imaging features of these abnormalities while providing a clear pictorial depiction of various unique hernias and hydroceles seen with this entity.