Overview
Cryptorchidism is defined as failure of the testis to descend from its intra-abdominal location into the scrotum. The exact etiology of cryptorchidism is not known. In one third of patients, the condition is bilateral. Ultrasonography (US), computed tomography (CT) scanning, magnetic resonance imaging (MRI), arteriography, and laparoscopy are used for diagnosis.
Orchiopexy is the treatment of choice and usually is performed in patients aged 2-10 years. A cryptorchid testis, shown in the image below, is 20-48 times more likely to undergo malignant degeneration than a normal testis. Orchiopexy does not alter the risk of malignant transformation. The incidence of malignant transformation also is increased in the unaffected testis. Consider hormone treatment with either human chorionic gonadotropin or gonadotropin-releasing hormone analogues for palpable high-scrotal position of the testis; however, efficacy is less than 20%. Surgical treatment is most effective and reliable.
Longitudinal sonogram of the right cryptorchid testis at the level of the inguinal canal. Intratesticular spectral Doppler waveform demonstrates normal low-resistance pattern of flow.
No radiologic intervention exists.
Ultrasonography is the first imaging modality performed on a cryptorchid testis. Of cryptorchid testes, 72% are in the inguinal canal; therefore, they are easily accessible to US examination. In addition, US is readily available and is easy to schedule.
If US cannot identify the testis (US effectively detects cryptorchid testis below the level of the internal inguinal ring), MRI and CT scanning are the subsequent modalities of choice. Both can detect an abdominal testis.
Laparoscopy is performed if MRI and CT cannot localize the testis,
but it is invasive and expensive.
US cannot detect an intra-abdominal testis, and CT scanning uses radiation and does not have multiplanar capability. MRI has better soft-tissue contrast and multiplanar capability; however, when the testis is higher in the abdomen, the presence of bowel loops lowers the sensitivity for detecting the cryptorchid testis.