The mother’s abdomen is opened in more or less the same way as in a cesarean section (1). The uterus is lifted partially out of the abdomen (2) and the site at which it is to be opened is determined with the aid of the ultrasound transducer. A small initial opening is made in the uterine wall between holding sutures to permit the introduction of an instrument (stapler) for making a longer incision (3). A stapler is used to make a longer opening in the uterine wall, all layers of the uterine wall being clamped toigether and any bleeding stopped (4). The lesion, with its soft and histologically intact spinal cord (arrow), has been brought to the middle of the opening in the uterine wall for the operation (5).