Ear Diseases in General Practice

THE frequency with which one meets with diseases of the ear in general practice is a reason why the general practitioner should have a clear practical knowledge of how to approach such cases with a view to their diagnosis, prognosis, and treatment. In approaching this subject it is essential to have a clear understanding of the anatomical divisions of the ear, and a good preliminary introduction to the study is often given by a careful study of the temporal bone. This should be obtained by referring to the many clear accounts in any modern textbook of anatomy. We learn there that the organ of hearing is divided into two principal divisions: the sound-conducting and sound-receiving apparatus. The sound-conducting apparatus-(a) the external ear, the auditory external canal; (b) the middle ear (the tympanic cavity with the tympanic membrane and ossicles, the eustachian and mastoid process). The sound-receiving apparatus-(a) the labryinth and cochlea; (b) the auditory nerve. Methods of examination of the organ of hearing.-The examination of the external auditory canal and of the tympanic cavity is the first essential for the diagnosis of disease of the ear. The membrana tympanicus is covered externally by the cutis of meatus and internally by the mucous membrance of the tympanic cavity. Hence it is in immediate relationship with diseases of the canal and of the middle ear. When these parts are diseased we recognise changes in the membrane which are obvious on inspection and enable us to form some conclusion as to the diseased state of the external and middle ear. We know from experience that disease of the tympanic cavity must frequently form a basis of diagnosis, and with this are noted changes on the tympanic membrane, so that the condition of the membrane is of great value in enabling us to diagnose diseases of the middle ear. We must not expect to find changes in the membrane in all cases of deafness, as in many patients with a high degree of deafness no change in the membrane can be seen. In order to make this observation we should be familiar with the practical method of inspection and have a practical knowledge of the use of a few instruments which are essential. We use ear specula-Gruber is a suitable pattern. These have an oval aperature, and are arranged in three or four sizes to suit the individual case. A head-mirror is essential to reflect light through this speculum from light reflecting on the mirror. The illumination used may be ordinary daylight or artificial light. Dressing-forceps of the pattern of Politzer and a small blunt olive-tipped probe of silver or copper are, as a rule, all that is necessary to enable one to diagnose and treat the most common diseases in these parts. If we wish to add a further method we employ Siegle's pneumatic speculum, which is indispensible for 219