Urachal remnants in asymptomatic children: gray-scale and color Doppler sonographic findings

PURPOSE: We undertook this study to evaluate the frequency of visualization and the sonographic appearances of urachal remnants (URs) in asymptomatic children. METHODS: One hundred eighty-two children without any urachus-related symptoms underwent sonography of the prevesical region and urinary bladder with high-frequency transducers. RESULTS: A UR was visualized in 180 (99%) of the children. The URs had a mean length +/- standard deviation of 13 +/- 5 mm. Most of the URs were ovoid, and most demonstrated a moderate protrusion into the bladder cavity. The URs with a central echogenic area were larger than those without central echogenicity. In 36 (61%) of the 59 URs that were evaluated with color Doppler sonography, vascular signals were demonstrated within the lesion. The URs with internal vascular signals were significantly larger than those without internal vascular signals. CONCLUSIONS: The gray-scale and color Doppler sonographic characteristics of URs seem to be related to their size and their degree of involution rather than to the age of the child. We think that URs are present in almost all children. URs should be considered normal findings if they are asymptomatic and their length is not significantly greater than 22.5 mm, the 95th percentile in our study.