ABNORMALITIES OF THE EAR FOUND BY OBJECTIVE EXAMINATION. - While the section of this paper on morbid anat omy will be mainly devoted to the path ological changes of the deeper parts of the ear, it is my purpose, under this head ing, to deal with the abnormalities found in those parts of the ear which are ac cessible to objective examination. It would naturally be supposed that as deaf mutism is often caused by anomalies of the ear, deaf-mutes would often exhibit congenital abnormalities of the external ear. This is, however, not the case, as congenital malformations of tbe external ear are but seldom met with. A close investigation of the cases of malforma tion of the external car reported in lit erature proves also that these abnormali ties are but very rarely accompanied by such a diminution of the powers of hear ing as to result in deaf-mutism, which circumstance has been laid much stress upon by Toynbee. Abnormalities of the external meatus have been often met with. It is, however, often difficult to decide the nature of the abnormalities from the descriptions of them we possess, and a comparison of the frequency with which they have been found by various investigators is, therefore, of no interest. Contraction of the meatus would seem to be the abnormality most frequently met with. The greatest interest, how ever, attaches to the closing of this pas sage, which has been found by many in vestigators without being accompanied by any malformation of the external car.
There can be little doubt that when the meatus is closed by a membrane situated close to the external ear this is due to congenital malformation; should the membrane, however, be situated in the neighborhood of the tympanum, it is pos sible that the obstruction is the result of inflammation in the tympanic cavity. I
have, at least, in two cases, observed such a closing of the external meatus of deaf mutes resulting from scarlatinal inflam mation, in the one case on both sides, in the other on one.
As to otoscopic examinations of deaf mutes, these have contributed very little to the pathogenesis or etiology of deaf mutism. Such investigations have been published by various authors, whose re searches, in spite of the care which has been bestowed upon them, have lead to very little result; in fact, the various authors differ very considerably in the results obtained. The difference ob served in the results of examinations of normal children and pupils at deaf-and dumb asylums lies in the greater fre quency with which the abnormalities found appeared in deaf-mutes, and not in the nature and kind of these abnor malities. All investigators who have classified the deaf-mutes examined by them according to the nature of their deafness (congenital, acquired, or doubt ful) agree that the otoscopic examina tion of the drum-heads in cases of con genital deafness yields a negative result more frequently than in cases of acquired deafness, the latter more frequently ex hibiting destructive inflammatory proc esses or the traces of such.