Contralateral Patent Processus Vaginalis in Unilateral Undescended Testis: Comparison between Preoperative Ultrasonographic and Transinguinal Laparoscopic Inspection

ABSTRACT

PURPOSE: The presence of a contralateral patent processus vaginalis (CPPV) is a risk factor for a metachronous hernia and may alter the surgical approach in unilateral cryptorchidism. We prospectively investigated the prevalence of a CPPV and compared the results between ultrasound (US) and transinguinal laparoscopy (TIL). MATERIALS AND METHODS: We analyzed a single surgeon's experience with preoperative US, TIL, and inguinal orchiopexy. We included 74 patients with a palpable (or identified by US) cryptorchidism with patent processus vaginalis who underwent inguinal orchiopexy. We performed an inguinal exploration when we could identify an opened internal ring through TIL. RESULTS: The prevalence of a CPPV was 18.9%. There was no significant difference in the occurrence of a CPPV by laterality, age, gestational age, or location of testis. A CPPV was detected 10 patients by US and in 15 patients by TIL, but one of them was revealed to be a blind pouch. The sensitivity and the specificity of US were 71.4% and 100%, respectively. Four CPPV cases were undiagnosed by US; all had a narrow internal ring. The accuracy of US was dependent on the width of the CPPV and the morphology of the internal ring. CONCLUSIONS: It was considerable that about 20% of patients with unilateral cryptorchidism had a CPPV, a risk factor for metachronous hernia. The presence of a CPPV in unilateral cryptorchidism should be considered in clinical practice.