Akira Nagasaki, Yoshio Zaizen, Takashi Kawanami^1）

Department of Surgery and Radiology^1）, Fukuoka Children’s Hospital

　　Ultrasonographic examination before and after treatment was made on 27 patients with hypertrophic pyloric stenosis who underwent pyloromyotomy and 10 treated with atropine sulfate. The clinical conditions before and after the respective treatments were compared regarding the diameter, length and thickness of the pyloric muscle, the region of the pyloric inner cavity and the volume of the pyloric part. The time-course changes in diameter as well as those in thickness and length of pyloric muscle of both groups were similar. These factors were smaller than the preoperative volume one month after but they became normal 3 months after the treatment. The cross-section of the inner cavity of the pylorus was not changed, except that the cavity was transiently enlarged nearly one week after the surgical treatment. The postoperative volume of the pyloric part became smaller than the preoperative volume 1week after treatment. The results indicated that food intake was possible even before morphological normalization of the pyloric part. It was therefore thought that some functional improvement might lead to the disappearance of vomiting in both groups.

Keywords：Hypertrophic Pyloric Stenosis, Ultra Sound, Pyloromyotomy, Atropine Therapy, Pyloric Muscle