Description: Segment 1 The intertitles introduce the patient, a 6-year-old boy, who has a scar in the ear area from a previous operation. The back of the boy's head is shown. Anaesthetic is administered. The ear is cleaned and an incision is made behind the ear. The intertitles give detailed explanations of the steps of the procedure. A fistula is exposed in the bone and a probe is inserted. Time start: 00:00:00:00 Time end: 00:05:12:15 Length: 00:05:12:15 Segment 2 The groups of air cells in the mastoid (part of the skull behind the ear) are scraped away. Hydrogen peroxide, rectified spirit and paraffin paste are applied to the area. A rubber drain is inserted into the area and the incision is sutured closed. Dressings are applied. Time start: 00:05:12:15 Time end: 00:09:50:15 Length: 00:04:38:00 Segment 3 The next operation shown is for abscess of the postaural lymphatic gland, which closely resembles mastoiditis. The back of the patient's head is shown. The abscess is seen, with pus oozing from a fistula. The operation begins and the tissue behind the ear is incised to the bone and the opening enlarged with scissors. A sample of pus is taken. The abscess wall is scraped away. Rectified spirit and paraffin paste are applied. A rubber drain is inserted. The wound is sutured and dressed. The intertitles explain the cause of the infection. A dissected bone is used to demonstrate the anatomy of the mastoid area. Time start: 00:09:50:15 Time end: 00:16:31:24 Length: 00:06:41:09