Why Do Our Colleagues Still Image for Cryptorchidism? Ignoring the Evidence

Abstract

To the Editor: Commenting on imaging for cryptorchidism by primary care providers (PCPs), Elder emphasizes its use in patients with nonpalpable testes. While this is one scenario that may lead PCPs to order ultrasound, our study and that of Tasian et al revealed that imaging is also commonly ordered in boys older than 1 year with palpable testes, indicating that these providers are unaware that ultrasound cannot distinguish a retractile from an undescended testis. We agree with Elder that education to end these practices requires, among other efforts, reports in the pediatric literature to reach PCPs, which we and Tasian and Copp have recently published. However, we also must comment on the review of nonpalpable testes, as it perpetuates misconceptions that hinder discussions between pediatric urologists regarding best management. While it may be true that overall 50% of nonpalpable testes are viable, data from prospective series indicate that findings are significantly different in boys with unilateral vs bilateral nonpalpable testes. Nearly all boys with bilateral nonpalpable testes have bilateral viable testes, whereas the majority (two thirds) of those with a unilateral nonpalpable testis have ipsilateral testicular loss, usually with a scrotal nubbin. The viable testes in the remaining third are found equally within the abdomen and extra-abdominally, meaning that only 15% of patients have an intra-abdominal viable testis. Compensatory hypertrophy of the contralateral descended testis, defined as length 1.8 cm or greater, positively predicts testicular loss in 90% of unilateral cases. From these data a rational approach can be devised that varies with the clinical scenario. Patients with bilateral nonpalpable testes likely have intra-abdominal testes, and initial laparoscopy is reasonable. A boy with a unilateral nonpalpable testis and compensatory hypertrophy on the other side most likely has a scrotal nubbin, and initial scrotal exploration is most efficient. Patients with unilateral nonpalpable testis and no contralateral hypertrophy most likely have a viable testis that, despite careful examination preoperatively and under anesthesia, has a 50% chance of being outside the abdomen. Here is another scenario in which preoperative ultrasound might be considered, to guide the surgeon toward initial laparoscopy vs an extra-abdominal incision. It is not concern about laparoscopy being a risky procedure that leads me most often to begin surgery for the unilateral nonpalpable testis with a scrotal incision. It is the evidence of what I am most likely to encounter, especially when testicular loss is anticipated.