Imperforate anus: US determination of the type with infracoccygeal approach.
OBJECTIVE
To assess the usefulness of infracoccygeal transperineal ultrasonography (US) in differentiation between high- and low-type imperforate anus.


METHODS
Infracoccygeal US was prospectively performed with a 7-10-MHz linear-array transducer prior to corrective surgery in 14 neonates with imperforate anus. The approach site was just inferior to the coccyx and posterior to the anus. Transverse images of the anorectal area were obtained. The puborectalis muscle was identified, and the relationship between the puborectalis muscle and the distal rectal pouch was evaluated. US findings were compared with surgical findings.


RESULTS
In 10 neonates, a low-type imperforate anus was correctly diagnosed at infracoccygeal US. In those with low-type imperforate anus, the puborectalis muscle was seen as a hypoechoic U-shaped band (n = 10), and the distal rectal pouch passed through the puborectalis muscle (n = 10). In four neonates with high-type imperforate anus, the puborectalis muscle was not identified (n = 4).


CONCLUSIONS
Infracoccygeal transperineal US enables the determination of the type of imperforate anus.
Han
Tae Il
TI
Department of Radiology, Eulji University School of Medicine, 24-14 Mok-Dong, Jung-Gu, Taejon 301-726, South Korea. tihan31@hanmail.com
Kim
In-One
IO
Kim
Woo Sun
WS
D001006:Anus, Imperforate / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D009132:Muscles; D011446:Prospective Studies; D012007:Rectum / Q000000981:diagnostic imaging; D012445:Sacrococcygeal Region / Q000000981:diagnostic imaging; D014463:Ultrasonography