RESUMEN
<p><b>OBJECTIVE</b>To evaluate the effect of the treatment of congenital hypertrophic pyloric stenosis (CHPS) with endoscopic pyloromyotomy.</p><p><b>METHOD</b>Nine consecutive infants (7 boys, 2 girls; age range 26 - 70 days; weight range 2.65 - 6.10 kg), with a diagnosis of CHPS according to typical clinical manifestations, transabdominal ultrasound (US), gastroenterography and gastroscope. All the cases had accompanying malnutrition, anaemia, metabolic alkalosis, and some were complicated with congenital heart disease. In gastroscope operating room, all the patients were given pentobarbital and midazolam intravenously. A gastroscope with an outer diameter of 5.9 mm was passed through mouth, stomach, pylorus to the descending segment of duodenum. Under gastroscopy, two incisions were made along the anterior and posterior wall of pylorus from the duodenal bulb to the antrum by using endoscopic electrosurgical needle knife and an arch sphincter sarcosome. Incisions were deepened by 2 to 3 procedures until the longitudinal muscle was exposed, about 2 to 4 mm according to transabdominal US performed before operation. The incision depth was 2 - 3 mm if pylorus wall was 4 - 6 mm in thickness; or 3 - 4 mm when the wall was thicker than 6 mm.</p><p><b>RESULT</b>The endoscope was easily passed through the pylorus to the duodenum post-operation. The transabdominal US and gastroenterography showed that liquid easily flew through pylorus. All patients were able to have regular feeding about 2 to 10 hours after the operation. Vomiting in all patients was significantly decreased in frequency and amount, and in 8 infants vomiting stopped within 1 week, in one case it did not stop until 1 month after the treatment. Some cases showed slight adverse reaction, no perforation or massive haemorrhage in stomach or intestines occurred in any of the patients during and post-operation. Eight infants were doing well at follow-up (range 2 to 9 months). One girl had recurred vomiting at normal feeding after a period of 1 month postoperation without vomiting. This case was cured by second endoscopic pyloromyotomy.</p><p><b>CONCLUSIONS</b>Endoscopic pyloromyotomy is effective, safe, simple, and offers several advantages: no need for open-abdomen surgery, feeding can be initiated rapidly.</p>