ULTRASONOGRAPHY OF PYLOROSPASM - FINDINGS MAY SIMULATE HYPERTROPHIC PYLORIC-STENOSIS

We compared sonographic images and measurements of patients diagnosed as having hypertrophic pyloric stenosis and pylorospasm among infants with projectile vomiting. Thirty-seven patients with hypertrophic pylo ric stenosis had an unchanged pyloric length (mean, 22.5 mm) and muscl e wall thickness (mean, 5.3 mm). Thirty-four pylorospasm patients had considerable variability in measurement or image appearance during the ir studies. Means of their longest or largest measurements were 14.4 m m for pylorus length and 3.8 mm for muscle wall thickness. Among these , 53% had muscle wall thickness of 4 mm or greater and 18% had pyloric length of 18 mm or greater during some portion of their study. We con cluded (after clinical follow-up study con firmed our ultrasonographic diagnoses) that pylorospasm may mimic hypertrophic pyloric stenosis f or at least a portion of a sonographic study. Muscle wall thickness or pyloric length measurements may overlap those accepted as positive fo r hypertrophic pyloric stenosis. Image or measurement variability is a n important clue for diagnosing pylorospasm.