Prenatal Presentation of Inguinoscrotal Hernia

Prenatal diagnosis of inguinal hernia is rare and easily confused with other entities, including masses of the scrotum, abdominal wall, and perineum. Pathologic processes of the scrotum rarely result in enlargement beyond 7 cm. Peristalsis can help to indentify bowel within the mass, suggestive of hernia or omphalocele rather than hydroceles or tumors that contain no bowel. Torsions have a double-ring appearance with no testicular blood flow, whereas hydroceles have visible testicles within a fluid-filled scrotum. Doppler evaluation may be helpful, as hernias typically have minimal vascularity, unlike tumors and teratomas, which are vascular with a widely variable appearance. The authors present the sonographic features of a late-presenting fetal mass that was clinically indistinguishable from omphalocele other than its skin thickness and was larger than typically reported for hernias. Skin thickness and subcapsular fluid are useful adjuncts in distinguishing inguinoscrotal hernia from omphalocele in late gestation.