Babies with hypertrophic pyloric stenosis (HPS) are generally healthy, normally developing infants in whom, suddenly, at the end of the first month of life, projectile vomiting develops. Clinically, a small “olive-shaped” tumor may be palpable. In this study, real-time ultrasound imaging was used in the evaluation of 57 cases of suspected HPS. The target sign, a hypoechoic ring of hypertrophied pyloric muscle, with a wall thickness of 4 mm or greater, proved to be a positive finding for hypertrophic pyloric stenosis. A pyloric channel length, or cervix sign, of greater than 1.4 cm was also a positive criterion for HPS. At the Children's Hospital of Philadelphia, we diagnosed 24 positive and 33 negative cases with 100% accuracy. High-resolution real-time ultrasound should be the first imaging modality used when evaluating cases of suspected HPS.
- hypertrophic pyloric stenosis
- pyloric stenosis