Abstract:
Objective：To summarize the value of ultrasonography in the diagnosis of congenital hypertrophic pyloric stenosis.
Methods：The ultrasonic instrument was used for inspection.Observe pyloric edema and measure the pyloric diameter and pyloric muscular layer thickness.
Results：In all 36 cases high-frequency ultrasound examination showed a typical hypoechoic ring performance；there was extension of the pyloric tube in the gallbladder；pyloric muscular layer thickening was hypoechoic ring, with a thickness of 0.40 to 0.62 cm；pyloric tube length was 1.7 to 2.4 cm, and anteroposterior diameter was 1.2 to 1.5 cm.The 36 cases of children received pyloromyotomy，and gastric dilatation didn't occur after surgery under ultrasonography in the 36 cases.
Conclusion：Ultrasonography can directly show the pathological manifestations of the disease, providing the basis for diagnosis and differential diagnosis, which is the first choice in the diagnosis.

Key words: pyloric stenosis, ultrasonography, diagnosis, children