Sonographic evidence for patency of the processus vaginalis in children with acquired undescended testis

Testes do ascend, but for unknown reasons. A testis may ascend through a patent processus vaginalis (PV). However, data for PV patency in acquired undescended testes (aUDT) are inconclusive. In this article, we aim to assess the sonographic PV diameter in boys with aUDT in comparison with normal group boys (obliterated PV) and boys with hydrocele or inguinal hernia (patent PVs). This retrospective study included 43 boys operated unilaterally for aUDT (n = 16), communicating hydrocele (n = 11) and inguinal hernia (n = 16). All selected patients had a preoperative measurement of the ipsilateral PV diameter. In addition, 17 boys with phimosis (normal group boys) were prospectively included, and underwent a sonographic examination of the inguinoscrotal area of a randomly selected side to measure the diameter of the respective PV. In total, 60 sides were examined. An aUDT was defined as a testis that had been identified at least twice previously in scrotal position. The results indicated that in normal group boys, PV could not be detected by sonography. In contrast, PVs ipsilateral to aUDT were visualized as hypoechoic tubules connecting the peritoneal cavity with the scrotum, similar to patent PVs in hydroceles. PV diameter in the aUDT group did not differ from the hydrocele group. However, PVs in aUDT and hydrocele were significantly narrower than in inguinal hernias. This is the first report of a patent PV in aUDT, comparable with hydrocele. Our findings suggest high ligation of the patent PV during orchidopexy.