From the Guidelines
You should not order an ultrasound for a patient with a suspected undescended testicle prior to referral, as imaging is not recommended by current guidelines. According to the American Urological Association (AUA) guideline on the evaluation and treatment of cryptorchidism 1, imaging for cryptorchidism is not recommended prior to referral, which should occur by 6 months of age. The guideline states that providers should not perform ultrasound or other imaging modalities in the evaluation of boys with cryptorchidism prior to referral, as these studies rarely assist in decision making 1.
The reason for this recommendation is that ultrasound has limited sensitivity and specificity in localizing a nonpalpable testis, with values of 45% and 78%, respectively 1. Furthermore, ultrasound cannot reliably localize a nonpalpable testis or confirm an absent testis. In fact, more than 70% of cryptorchid testes are palpable by physical examination and need no imaging, and for nonpalpable testes, surgical exploration such as diagnostic laparoscopy may be necessary to confirm the presence or absence of the testis 1.
Therefore, physical examination and referral to a specialist are the preferred initial steps in the evaluation of a patient with a suspected undescended testicle, rather than ordering an ultrasound. This approach prioritizes the patient's morbidity, mortality, and quality of life by avoiding unnecessary imaging and ensuring timely referral to a specialist for further evaluation and treatment.
From the Research
Ultrasound for Undescended Testicle
- The use of ultrasound in diagnosing undescended testicles is not recommended as a primary diagnostic tool, as stated in the study 2.
- According to the study 3, real-time ultrasonography was used to detect the anatomic positions occupied by undescended testicles, and the testis was demonstrated as an echo-poor, oval structure in 95% of examinations.
- However, the study 2 suggests that imaging should not be used in the workup of undescended testes, as no current modality has been shown to be adequately sensitive or specific to aid in management decisions.
- The study 3 found that ultrasound can characterize the positions occupied by the testis and classify them accordingly, but estimation of testicular volume by sonography was unsuccessful compared with intraoperative measurements.
Alternative Diagnostic Approaches
- Physical examination of the testicle can be difficult, and consultation should be considered if a normal testis cannot be definitely identified, as stated in the study 4.
- Patients with undescended testicles should be evaluated by a pediatric urologist or other qualified subspecialist who can assist with diagnosis and treatment, as recommended in the study 4.
- Diagnostic laparoscopy is often used for non-palpable testes, as it allows for the identification of an atrophic or absent testicle and provides an opportunity to perform an orchiopexy simultaneously, as stated in the study 2.