MEDICAL OTOLOGY.

BY GEORGE STRAWBRIDGE, M.D.

In this article on Medical Otology it is proposed to include those diseases of the ear that are frequently seen by the general practitioner, and especially those that exist as sequelæ to some general disease, and where the ear complication would be treated in connection with the general disorder.

Examination of a Patient.

As nearly all ear patients are afflicted with varying degrees of deafness, one of the first points of inquiry will be as to their hearing power. There are three tests commonly employed for this purpose: the ticking of a watch, the human voice, and the tuning-fork.

1st. The Watch.-By this method of examination the patient is placed with closed eyelids, so as to exclude the visual power as a factor in the examination, as it is a curious fact that many people are apparently unable to distinguish between seeing a watch and hearing its tick, and therefore so long as they can see the watch they will imagine that they can hear it ticking. Bring the watch (held by the physician) from a distance toward the patient until the tick is heard, and note the distance in inches. The plan of holding the watch close to the ear, and then slowly removing it until the extreme limit of hearing is attained, gives an incorrect result as regards the distance that the watch can be heard, due to the fact that the impressions produced on the terminal endings of the auditory nerve by the watch-tick continue a sensible time after the watch-tick has passed out of the nerve-limit, and therefore the watch-tick can still be noted. Prout has prepared a convenient method for recording the hearing power. Note the number of inches that the watch-tick can be heard by a normal ear, and let this serve as a denominator of a fraction, the numerator of which is the number of inches that the same watch-tick can be heard by the ear of the person under examination. For instance: a normal ear can distinguish my watch-tick at a distance of twenty inches; if, now, the patient's ear can perceive the same sound at only five inches, the hearing power would be noted as By this it is not meant that the hearing power is one-fourth of normal hearing, as it would be only one-sixteenth of normal hearing, as the volume of sound is inversely in proportion to the square of the distance.

2d. The human voice tells more about the hearing power for practical purposes than does the watch. There are many persons who can readily

hear the watch-tick at several inches, and yet who hear very imperfectly ordinary conversation, and also many who hear very well the human voice and very badly the watch-tick. The method of examination is to speak ordinary words in a tone that can be heard by the average ear a given number of feet, and to note the distance in feet that the ear under observation can detect the words that are spoken. In this way can be noted the hearing power of the human voice, the numerator of the fraction being the distance that the word can be heard by the observed ear, the denominator being the distance that the word can be distinguished by the normal ear.

The patient should always be examined with closed eyelids, as deaf people quickly learn by watching the movements of the lips of the speaker to know the words that are being spoken. Another precaution is to have the ear to be tested directly opposite the mouth of the observer, the other ear being firmly closed.

3d. The Tuning-Fork.-Bone-conduction of sound is used by this method. The great use of the tuning-fork is in determining diseased conditions of the auditory nerve and internal ear, and it enables one to make a differential diagnosis as to whether deafness is due to a diseased condition of the sound-conducting apparatus or whether the nerve portion of the ear is at fault. For instance: a patient complains of deafness. This may be due to some obstruction in the external auditory canal, such as impacted cerumen, or it may be due to a diseased middle ear, with thickening of its membranes, or it may be due to a diseased internal ear. The watch and human voice would only show the ear to be defective in its hearing power, and it may be from any of the above-mentioned causes. The tuning-fork, in vibration, placed on an incisor tooth or on the frontal bone, would bring out the fact that if the deafness was due to a diseased middle ear or obstruction in the external auditory canal, the tuning-fork would be heard best by the defective ear; but if due to a disease of the internal ear, it would be heard the least distinctly by the defective-hearing ear. Mack explains this by the supposition that the sound-waves are prevented from freely escaping through the sound-conducting apparatus, and are reflected back on the auditory nerve-elements, and thus make a double impression. Tuning-forks having the note C are best adapted for this examination.

EXAMINATION OF THE EXTERNAL CANAL AND TYMPANIC MEMBRANE. This can be done by direct or by reflected light, better by the latter. A mirror and speculum are needed. The mirror should be concave, with a focal distance of from 5"-7" and a diameter of 23"-3", with a ball-and-socket-joint and head-band, so as to allow of the two hands being free, the head holding the mirror in the required position. The mirror should have a central perforation of 2"-3", with a brass back, rendering it less liable to break. As a light-source can be used the light from an argand burner, but preferably sunlight reflected from a cloud or white wall.

The Ear Speculum.-The Wilde or Gruber speculum answers equally well. The Wilde speculum is cone-shaped, and best of German silver: it is easily cleansed and has four sizes. The Gruber speculum has a larger mouth and gives a large visual field. It has a parabolic curve, for the purpose of admitting more light; there are also four sizes.

The

speculum should be warm when in use, and is to be held in position in the canal by the thumb and forefinger of the left hand. Often in the examination of an external canal an angular-toothed forceps is needed to remove foreign substances.

The cotton-holder is a most important instrument, furnishing a means of thoroughly drying the external canal of any fluid with the least possible amount of irritation-much less than that caused by the use of the ear-syringe. It is a slender steel rod 6" long, having a number of serrations at one end to more easily allow cotton to be wrapped around it; the other end has a convenient handle. In using this instrument a small tuft of well-cleansed cotton is wrapped around the holder, so that one half of the length of the cotton tuft projects beyond the end of the instrument. By slight adaptation with the fingers the cotton roll can be made soft or quite firm, and large or small in proportion to the amount of cotton used. The cotton-holder should always be used under the light from the head-mirror.

The curette is of the same length as the cotton-holder, but is made of heavier steel, and terminates at one end in a small ring of a diameter of from 2-3 mm. It is useful in removing scabs, etc. from the external canal, also in loosening impacted cerumen.

Probes are also needful. A good middle-ear probe is made of a single piece of silver, of the same length as the cotton-holder, and tapering down to a slender shank with a small knob-like ending.

The ear syringe, a most excellent instrument, is now made of rubber, holding two ounces of fluid, and has a bulbar extremity, so as to avoid injuring the external canal or tympanic membrane. The syringe has a finger-rest, with the piston ending in a ring, so as to admit of its use with one hand. In using a syringe warm water should be always employed, and at a temperature that the finger would indicate as being quite warm. Also at first force the water very gently into the meatus, so that the patient shall not be startled; also it is well to bear in mind that many patients become very giddy under its use, necessitating either very gentle use or its being abandoned for the time.

EXAMINATION OF THE EUSTACHIAN TUBE.-The main point is as to whether the tube permits the free passage of air up to the middle ear. This can be ascertained by three methods: 1. Valsalva's method; 2. Politzer's method; 3. Catheterization of the tube.

Valsalva's method consists in forcing air through the tube by a forced expiration, the mouth and nasal passages being at the same time firmly closed. The patient can distinctly feel the air pressing against the tympanic membrane, causing it to bulge outwardly, provided the tube is open. This proceeding has certain disadvantages, sometimes causing head congestions and giddiness.

Politzer's Method.-In this proceeding a gum air-bag is used as the means of forcing air into the tube. In the act of swallowing the soft palate is drawn against the posterior wall of the pharynx, and at the same time the pharyngeal mouth of the tube is well opened, so that air forced through the nasal passages at such a moment, being prevented from passing downward by the up-drawn palate, is forced up through the Eustachian tube into the middle ear. The success of this procedure depends entirely upon the inflation being made at the same moment that

the soft palate is drawn up against the pharyngeal wall; otherwise the air would naturally pass by the widest passage, in this case downward into the stomach. The usual plan of inflating at the moment that the patient is told to swallow fails, from the fact that patients differ so materially in the quickness with which they respond to an order. Many in their anxiety will swallow before the word is given, others will allow an appreciable time to pass before swallowing, so that the inflation will fail. For this reason I have adopted the following plan: It is well known that in the act of swallowing the larynx is drawn forcibly upward, and also that the moment of the extreme elevation is nearly coincident with the moment that the soft palate is drawn against the wall of the pharynx. The prominence of the thyroid cartilage (the so-called pomus Adami) enables one to easily watch until the maximum elevation of the larynx is reached, and then quickly, by a forcible contraction of the air-bag, to thoroughly inflate the middle ear. The Politzer method so thoroughly accomplishes the object, and with the least possible irritation, that the use of the catheter in the majority of cases is no longer indicated. The method of Politzer is as follows: The patient takes some water in the mouth; the air-bag has attached to it a short piece of gum tubing ending in a nose-piece in shape like an olive, or sometimes a small gum catheter is attached to it. This is placed in the lower nasal passage and the nose held firmly closed over it with one hand, the second hand grasping the air-bag. The patient is then told to swallow, so as to cause elevation of the soft palate (this can also be accomplished by the patient speaking quickly some word like hoc), and the air-bag is forcibly pressed. In this way the air is quickly driven, viâ the nasal passage and Eustachian tube, into the middle ear. In little children it is sufficient to quickly inflate, as the crying of the child elevates the soft palate to a certain degree, and so cuts off the downward passage into the stomach.

External Ear Diseases of the Auricle.

ECZEMA. This disease occurs very frequently in infants during dentition, where irritation of the dental branches of the fifth pair of nerves causes irritation in other branches of the same nerve, including those distributed to the skin of the face and auricle, causing acute attacks of the disease. It is also frequently observed that successive teeth penetrating the periosteum will cause fresh attacks of this skin irritation, so that as long as the teething process continues, so long is the eczema apt to continue, and treatment will probably prove only palliative. Eczema occurs also in both the male and female approaching the period of adolescence, a time when other forms of skin disease are especially common.

The aged do not escape this annoying malady, where it is apt to occur in the chronic form, and is due to want of nerve-force in the skin branches of the nerves distributed to this part-a wise provision of nature allowing nerve-power to fail first in the nerves distributed to parts where the harm done is a minimum one, rather than in the nervecentres, where disease fatal to life would result. The treatment in this class of cases would be radically different from the preceding divisions, where nerve-irritation is the cause.