Hypertrophic Pyloric Stenosis
Case Detail
| Anatomy: Gastrointestinal |
Joseph Junewick, MD FACR |
| Diagnostic Category: Developmental |
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| Created: over 3 years ago |
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| Updated: over 2 years ago |
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| Tags:
PEDS
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| Modality/Study Types:
US
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Activities: PDF ImageJA |
History
2 month old female with vomiting, weight loss and metabolic alkalosis.
Case Images
Diagnosis
Hypertrophic pyloric stenosis (HPS)
Findings
Abrupt change in the muscle thickness at the antropyloric junction.
Hypertrophied pyloric muscle invaginating into the gastric antrum.
Pyloric muscle measuring >3 mm.
Thickened pyloric mucosa.
Discussion
HPS is related to hypertrophy of the circular muscle layer of the pyloric channel leading to gastric outlet obstruction. The etiology is unknown but theories include hypervascularity of the pylorus, neurochemical disturbance or enteric hormone imbalance. Onset of disease is between 3 weeks and 3 months with very few cases outside this time period. Males are 4 times as likely as females to develop pyloric stenosis. Genetics may influence disease development. Pyloric muscle thickness greater than 3 mm is the most predictive US finding of pyloric stenosis; channel length greater than 16 mm, channel width greater than 12 mm are also helpful in discriminating between a normal and abnormal pyloric channel. On cinegraphic evaluation, gastric peristalsis is initially vigorous but decreases as the metabolic perturbation worsens, the distensibility of the pylorus is significantly decreased and little or no gastric contents pass through the pyloric channel. The pyloric mucosa and muscularis may be hyperemic on Doppler evaluation.



