Role of Ultrasonography in the Preoperative Assessment of Impalpable Testes: A Single Center Experience

Background. Abdominoscrotal sonogram is often used in boys with a nonpalpable testis to determine the presence of the testis. We describe our experience with the use of ultrasonography in boys with a nonpalpable testis. Methods. We retrospectively reviewed the medical records of boys aged less than 14 years, who underwent preoperative ultrasonography for an impalpable undescended testis (IUDT) between 2006 and 2010 in our institution. The results of sonography and laparoscopy were compared. Results. A total of 26 impalpable testes in 22 patients, including 4 with bilateral impalpable testes, were preoperatively assessed by ultrasonography for their localization. Sonography localized only 6 of the 26 (23%) testes, which were laparoscopically explored and followed by orchiopexy. Conclusion. Ultrasound is not reliable in the preoperative assessment of patients with impalpable testes. 1. Introduction About 1-2% of boys at age 1 year have an undescended testis (UDT); this disorder is unilateral in about 90% of cases and bilateral in about 10% [1–3]. Almost one-fifth of undescended testes are nonpalpable [4]. Approximately 50% of nonpalpable testes are abdominal, with 45% being atrophic secondary to in utero spermatic cord torsion, and 5% being in the inguinal canal [5–7]. Among the radiologic methods used to try to “localize” the nonpalpable testis preoperatively are retrograde venography, computerized tomography (CT), magnetic resonance imaging (MRI), and sonography [8–12]. Abdominoscrotal sonography appears promising for the evaluation of impalpable testes, as it is noninvasive, with no radiation risk, and does not require sedation or general anesthesia. We describe our experience with ultrasonography in the preoperative diagnosis of impalpable testes. 2. Methods We retrospectively reviewed the medical records of all patients less than 14 years who underwent abdominoscrotal ultrasonography for impalpable undescended testes (IUDT) between 2006 and 2010 at our institution. Data reviewed included patient age at surgery, ultrasound results, and intraoperative laparoscopic findings. The results of sonography were compared with those of laparoscopy. 3. Results We identified a total of 22 patients with 26 impalpable testes, including 4 patients with bilateral impalpable testes, who underwent ultrasonography during the study period. Average patient age at the time of laparoscopy was 31 months. Ultrasonography was successful in localizing 8 of 26？(31%) testes (Table 1). Table 1: Comparison of ultrasonographic and operative findings. Only 6 of 26？(23%) testes