Short segment pyloric narrowing. Pylorospasm or pyloric stenosis?

Short segment narrowing of the pyloric canal is a common finding in infants with chronic vomiting, and most often is due to pylorospasm. In such cases, it is transient, and offers no real problem in diagnosis. On the other hand, when it persists, a question arises as to whether it is due to fixed stenosis. Differentiation of the two conditions is difficult, but important, for while spasm can be treated medically, true stenosis requires surgical intervention. Just how to accomplish this differentiation is the subject of this report, and for the most part, centers around the infant's response to a therapeutic trial of antispasmodics. Patients with pylorospasm respond favorably, while those with fixed stenosis do not. Generally, these latter patients require pyloromyotomy, but in the occasional infant, so little muscle hypertrophy is present that we have found pyloroplasty to be the preferred procedure.