Reliability of ultrasound for the diagnosis of hypertrophic pyloric stenosis.

An ultrasound (US) examination might be the best way to study the pylorus and its pathological states once the reliability of this technique has been demonstrated. In order to evaluate the reliability of a sonographic diagnosis of hypertrophic pyloric stenosis (HPS), 17 randomly chosen patients with HPS were examined with both ultrasonography and radiography and then operated on or followed up clinically. Rank correlation between the size and morphological features of the pylorus was found in babies with HPS using US. No false positives or negatives were obtained, and all true positives and negatives were detected. Because of this and the safety of the US technique we wish to emphasize that it should be considered the method of choice in screening infants with severe vomiting. Whenever HPS is suspected from clinical observation, ultrasonography should precede a radiological examination before surgery.