Also known as Ramstedt's operation or Ramstedt's pyloromyotomy, this is an operation performed on a baby with pyloric stenosis to relieve the blockage.
Basically, after the stomach has been emptied via suction through a naso-gastric tube, an incision is made on the abdominal wall, the stomach is visualised and the pylorus brought up outside the abdomen. Then, a longitudinal cut is made in the hypertrophied muscle and the muscle fibres are separated by blunt dissection up to the mucosa. This releases the pressure on the pyloric sphincter. After that, its only a matter of closing up the abdominal wound.
Complications in this operation are rare but care must be taken to ensure that the mucosa is not accidentally perforated during surgery as this could lead to peritonitis.