Sonographic findings of coccygeal abscess in the neonates

The purpose of this study was to report the sonographic findings of neonatal coccygeal abscess, previously not described. Eighteen neonates (5-18 days old) presented with swelling in the coccygeal area and by either open drainage (n=13) or follow-up after antibiotic therapy (n=5), this was diagnosed as coccygeal abscess. We retrospectively reviewed the size, shape, location, echo pattern and marginal characteristics of the abscesses, as seen on sonography, as well as their intradural content and relationship with the spine. Additional MR images (n=5) were separately reviewed. Coccygeal abscesses were confined to the subcutaneous fat layer and were either isoor hypoechoic compared with surrounding fat. In neonates, abscess formation in the coccygeal area is possible and coccygeal abscess should therefore be included in the differentiation of coccygeal masses. (author). 7 refs., 3 figs