Hypertrophic pyloric stenosis – classically presents as…
Hypertrophic pyloric stenosis – classically presents as non-bilious projectile vomiting during the second month of life. Ultrasound is excellent for first line assessment with the pylorus considered hypertrophied if it exceeds 15mm in length and 3mm or more in thickness (from lumen to outer edge). The stomach will usually be distended with fluid and at no time during the scan will the pylorus open. The cervix sign (left image), antral nipple sign and target sign are commonly described in pyloric stenosis but really they are of little relevance compared to direct muscle measurements.
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