370 THE EAR DIAGNOSIS. This is made by attention to the following points: (1) The clinical characteristics of the case already described. (2) Examination of the ear discharge for tubercle bacilli. (3) Microscopic examination of granula- tions removed from the middle ear. (4) Guinea-pig inoculation. (5) The findings at operation—enlarged caseous glands, presence of necrosed bone, pale flabby granulations, putty-like pus in the tympanic antrum, extensive caries of the bone and necrosis of the labyrinthine wall. (6) Microscopic examination of the swollen and infiltrated mucosa removed at operation. TREATMENT. This consists of intensive chemotherapy with antituberculous drugs but surgical treatment may also be required. SYPHILIS OF THE EAR Congenital Syphilis. After epidemic cerebrospinal meningitis and middle ear suppuration, this condition once ranked as the most frequent cause of acquired deaf-mutism. It is probable that some cases of so-called 'congenital' deaf-mutism are still due to intra-uterine syphilis or to syphilitic changes in the ear occurring before the child has learned to talk. Statistics as to the frequency of deafness in children suffering from congenital syphilis vary from 30 to 60 per cent. 1. In the fetus and infant. The most severe forms of ear syphilis probably occur in intra-uterine life. The infants show all the signs of congenital deaf- ness, and the static labyrinth is not excitable. Otitis media is of common occurrence in syphilitic infants. In some the infective process involves the labyrinth by rupture of the annular ligament. 2. In young children suffering from congenital syphilis what appears to be a case of simple Eustachian catarrh runs a protracted course. The usual treatment has little effect, and the drumheads remain thickened and indrawn, while the deafness is severe and persists. There is a combination of middle ear catarrh and labyrinthine deafness. 3. The late type of congenital syphilis, where deafness occurs usually between the seventh and thirteenth years, may be due to: (a) Otitis media followed by invasion of the labyrinth capsule and degeneration of the mem- branous labyrinth (Figs. 192, 193). In cases of congenital syphilitic deafness the tympanic membranes are seldom normal, pointing to a past attack (or attacks) of otitis media. (Ł) Syphilitic osteomyelitis of the bony labyrinth capsule due to spirochaetal blood infection, (e) Syphilitic neuritis of cochlear nerve. CLINICAL ASPECT. The patient is very often the eldest living child of the family and, on questioning the mother, a history is often obtained of mis- carriages and stillbirths preceding the birth of the patient. Females are affected much more frequently than males. As a rule eye trouble (inter- stitial keratitis) comes on 2 or 3 years before the deafness. 'Hutchinson' teeth (peg-shaped, notched incisors) are present in 50 per cent of cases (see Fig. 22, p. 39). Deafness may come on in one night; in such cases the vestibular tests give normal results, thus pointing to an isolated affection of the cochlear nerve. In other cases the onset of deafness is gradual, but eventually the patient becomes completely or almost completely deaf. In the early stages the deafness is probably of the middle ear type. As a rule, however, the case is not seen till later, when perceptive deafness is present.