The application of magnetic resonance imaging for the preoperative localization of nonpalpable testis in obese children: an alternative to laparoscopy.

Abstract

Tennenbaum et al reported more than 95% success for laparoscopic examination, which has supplanted other diagnostic modalities for locating nonpalpable cryptorchid testes. 1 The open Hasson technique for pediatric laparoscopy has emerged as a preferred method at many institutions because of its lower complication rate. However, it may be difficult to perform this procedure in obese children. We report 2 cases in which magnetic resonance imaging (MRI) accurately localized testes and provided an efficient algorithm for management while avoiding a potentially arduous procedure. CASE REPORTS Case 1. D. P., a 6-year-old obese male, presented to our pediatric urology service for management of a left undescended testis. Physical examination revealed a markedly obese boy weighing 69.5 kg. (50th percentile equal to 20 kg.). The scrotum contained a normally palpable right testis and but the left testis was not palpated. Body habitus and prepubertal status made palpation of a canalicular testis difficult. Pelvic MRI using coronal T1 images identified the testicle in the left inguinal canal (fig. 1). Orchiopexy performed via the standard inguinal approach was uneventful. Case 2. A. B., a 19-year-old markedly obese male weighing 115 kg. presented with hypogonadotropic hypogonadism and delayed puberty. Male karyotype was normal (46XY), and luteinizing hormone and follicle-stimulating hormone were less than 2 mg./dl. each (normal 0.2 to 8.0 and 0.5 to 5.3, respectively). The patient responded well to testosterone replacement. Physical examination demonstrated an empty hypoplastic scrotum. No testis was palpable in either inguinal canal and assessment was difficult due to body habitus. Ultrasound was not helpful but pelvic MRI clearly identified the testes in the inguinal canal bilaterally (fig. 2). A low Pfannenstiel incision facilitated exposure and mobilization of each testis to the scrotum without difficulty. DISCUSSION Laparoscopy for nonpalpable undescended testis is a safe and simple method of diagnosis with an accuracy of 95% to 100%. 1 Laparoscopy may be done not only for localizing, but