A manual of diseases of the ear / by George P. Field.

  • Field, George P.
Date:
1893
Catalogue details

Licence: Public Domain Mark

Credit: A manual of diseases of the ear / by George P. Field. Source: Wellcome Collection.

    18/486 (page 4)
    i probablj had its origin in the fact that counter-irritation near; the orbit relieves, in some derivative way, the conjunctival: congestion. | Short thick hairs at the entrance of the external auditory i raeatus guard it somewhat against the intrusion of insects and | floating foreign bodies generally, as at the anterior nares. The j wax secreted by the glands of the canal-walh keeps the integu-| ment from drying and chapping. ' The delicate skin between the re-entering angle of the pinna; and the mastoid process is frequently the seat (especially in children) of intertrigo or eczema. The latter condition not in-1 frequently gives rise to enlargement of the lymphatic gland j over or below the mastoid process. The presence of this lym-j phatic gland should be borne in mind: it is often the seat of ! abscess from impetigo capitis. It may also take on a chronic | enlargement, like the glands under the sterno-mastoid or, indeed,! in any other region. j A small branch of the pneumogastric nerve (Arnold's) is here] distributed. This is the twig which the alderman stimulates! after dinner with the corner of his napkin dipped in rose water, | so . causing the stomach to hurry on the digestive process withj renewed energy. i The external auditory meatus is about three-quarters of an| inch long, and starting from the depths of the pinna (concha), j between the condyle of the jaw and the mastoid process, passes | at first a little upwards and then slightly downwards, until it I reaches the tympanic membrane. The main course of the canal,j like that of the petrous portion of the temporal bone itself, is' inwards and slightly forwards. Like an hour glass, it is some- what smaller at the middle than at either end; so that the^ surgeon may experience considerable difficulty in getting ai cherry-stone or a pea at its inner end back through the straits. | The cul-de-sac being considerably larger than the foreign body,' this will lie loosely, and will not set up nearly so much infiam-; mation as if it were tightly jammed at the narrower part of the! meatus. j The external meatus is partly bony, partly cartilaginous. The i latter is a split tubular inward prolongation of the auricle with! I ■ - i I .1