7. What special investigations would you use to investigate congenital hypertrophic pyloric stenosis? Posted on April 19, 2023 Correct answer: (1) Ultrasound. (2) Abdominal X-ray. (3) Barium meal. Post navigation Previous Post6. What are the differential diagnoses for congenital hypertrophic pyloric stenosis? Next Post8. Why is ultrasound used to investigate congenital hypertrophic pyloric stenosis?