Robert Sonnenschein

VII. A Study of the Schwabach Test in One Hundred Cases

The study here presented was made on 100 unselected cases in the University Nose and Throat Clinic of Professor Gerber of Koenigsberg in 1909. These were examined in detail by means of all the usual functional tests. The result of the analysis of the Weber test (read before the Chicago Laryngological and Otological Society in February, 1911) and of the Rinne test (accepted as a thesis by the American Laryngologkal, Rhinological and Otological Society, June, 1921) have already been published, and I will take the liberty of quoting somewhat from these papers. The writer. believes that the great importan~e of the functional testing of the ears warrants the reporting of detailed findings. Inquiries addressed to prominent European otologistsat the time examination of the cases was in progress gave the following information regarding the forks employed and the region of the head on which they were placed. While we are perhaps accustomed to regard the Schwabach test as made by holding the fork in the midline of the vertex, many of the otologists quoted use the mastoid processes (just as in the Rinne) or the forehead instead of the vertex. In this country Randall and others employ the Gardner-Brown modification with the fork at the nasal root and the head bent backward.Panse (Dresden) employed the a fork (435 v. d.) on the mastoid process; Heiman (Warsaw) uses the weighted C (64 v. d.) and c (128 v. d.) fork, usually on the vertex; Schmiegelow (Copenhagen) uses a1 ( 435 v. d.) on the vertex; Urbantschitsch (Vienna) uses -c (64 Vo do), c (256 v. do) and c2 (512 V. do) on the mastoids; Hartmann (Berlin) ap-

XIV. Some Very Accurate Measurements of the Amplitude of Vibration of Tuning Fork Prongs

I have always been in favor of accurate methods in all functional testing of hearing. In order to have this, it is necessary that instruments which one uses, such as tuning forks, etc., be properly calibrated and that a definite technic be employed in order to get uniform and comparable findings. In the work done with the Webster phonometer, some years ago, it was found that apparently the greatest intensity of vibration emanated from the broad or outer surface of the prongs, a little less from the narrower surfaces, still less from the ends, and least of all from the edges or angles formed by the broad and narrow surfaces. Some forks have prongs which show a quadrilateral cross section so that one cannot say a broad or outer surface if the outer surface and the anterior surface are of the same width. At the time that the tests were made we did not realize that the shape of the prongs (that is, whether quadrilateral or oblong), the distance between the prongs or its relation to the width of the prongs made any particular difference regarding the relative intensity of one or the other side of the prongs. It was not until Mr. Eisenhour of the Riverbank Laboratory called my attention to the possibility that these factors might have some influence that I decided to check the results I had obtained in 1924, in order to definitely settle the question, and also to modify my statement, if necessary, in order that the full truth might be known. In order to test these points, Mr. Eisenhour and Mr. Tyzzer very kindly instituted some experiments at the Riverbank

LXVIII. The Use of the New Magnesium Alloy Tuning Forks

For the functional testing of hearing, many methods have been devised. Although the human voice is difficult of standardization as regards intensity and pitch, still in many ways it is the most practical method. If care is taken to use only the residual air for unaccentuated conversation or whispered voice, and every effort made to employ the same intensity and pitch, with the patients always standing in the same part of the room, the eyes closed or averted from the speaker, with no part of the body touching the walls or furniture, using both high and low pitched tones, approaching the patient from the greatest possible distance, and noting at which point he first begins to answer properly; if these various precautions are observed, sufficiently definite conclusions may be reached. After all, the actual efficiency of the ear is its ability to understand the spoken voice and, therefore, even though the tests cannot be made entirely accurate, they are very valuable from a practical standpoint. If the patient is able to hear sounds below one hundred double vibrations or above 4,000 double vibrations, but is unable to hear those between 100 and 4,000, he is deaf to all intents and purposes because he cannot understand the spoken voice. While the fundamental sounds of speech lie in the range between b-l and g-2 (according to the theory of Bezold), we must remember that the overtones or harmonics which give a special quality to the voice have a much higher range, the overtones of some of the vowels such as e reaching above 3,000 double vibrations. The watch, acoumeter and other instruments have been used, but these, from a scientific standpoint, are not very valu-

XXV. The Rationale of Tuning Fork Tests

A definite diagnosis is needed before prognosis can be decid: ed or treatment instituted, and to arrive at the diagnosis careful examination is essential. To do this properly, definite rnethods are necessary, and one must decide on a regular routine to get comparable results. Instruments of precision are required and they must be properly handled in order to obtain accurate results. The psychology of the patient is important, as the hearing tests are subjective and not objective. It is, therefore, important to note whether the individual is cooperating, whether he is overanxious and tries to anticipate findings, or whether he is simulating disease and thus thwarting the test in every possible way.

XXVIII. Methods and Interpretation of the Fundamental Tests of Hearing

The purpose of functional testing of the hearing is twofold: first. to determine the presence of impaired hearing and the degree thereof; and secondly, to decide the localization of the hearing defect, if any. Various methods have been devised to determine the presence of impaired hearing. As it is most important in intercourse with the rest of mankind to hear and appreciate the spoken language, it is by means of the voice that we learn whether an impairment is present or not. From the practical standpoint it is most important to know to what degree the hearing for the voice has been changed. Many appliances which will be mentioned later have been devised to gauge the degree of the hearing impairment. The determination of the localization of the hearing defect-s-that is to say, whether impairment is in the conduction apparatus (the external auditory meatus, the middle ear, the eustachian tube), or wkether the changes lie in the perception apparatus (the inner ear with its organ of Corti, or in the auditory nerve), is made to a very large extent by means of tuning forks, as well as the employment of the Galton whistle and monochord for the lIighest tones. Xluch can be learned regarding the state of the individuals hearing by an observation of the patient before any other tests are undertaken. The pitch of the voice helps us in differentiating between impairment of the conduction and perception apparatuses. When there is marked middle ear deafness, as, for instance, in an otosclerosis or a chronic tubal catarrh, the patient has an autophonia-s-that is to say, his own voice sounds very loud to him. He thinks it also appears very loud

XXIII. A Suggestion regarding the Rinne Test

While various constructions have been placed upon, and different deductions drawn from, the test devised in 1855 by Dr. A. Rinne, we probably all agree with Bezold that of the tests usually made, namely, the Schwabach, Weber and Rinne, the latter is the most reliable. This is so because in applying it one can more easily get from the patient intelligent and distinct answers, thus noting more definite findings. Rinne himself performed the test by placing the vibrating fork on the inner incisor teeth, but the method afterwards used by Bezold, Politzer, Urbantschitsch, and the other authorities (such as Boenninghaus, Gruber, Jacobson, etc.), is the one now in vogue, and probably used by all of us. This consists in striking the fork, the one advised by Bezold being a1 (435 v. d.), and placing the stem on the mastoid process. When no longer heard, the prongs of the fork are held near the auditory meatus and the length of time noted by which the air conduction exceeds the bone conduction, when the test is positive. Where the Rinne proves to be negative, the air conduction is first determined and the fork then placed on the mastoid. Please pardon this trite statement in the presence of otologists, as it is made only for the sake of completeness. It is not my intention now to discuss the various types of Rinne reaction, their clinical significance, nor their relation to the other functional tests, but will leave such consideration for another occasion. At present I desire merely to point out a fact, which, so far as my perusal of the literature goes, seems to have escaped the attention of most men of late, and that

LXXI. Schaefer-Galton Whistle

Whatever its actual value to the profession may be, it seems to me whenever a new instrument or modification of some appliance pertaining to our specialty appears, it is no more than proper that the same be called to the attention of our colleagues as soon as possible. When in Berlin last September, I spent a little time with my good and distinguished friend, Prof. Karl M. Schaefer, who has, as you know, done so much work in the physiology of the ear and in connection with various apparatus used in acoustics, and in otology. It was his resonators with which I did work that I have reported to you before, and it was he who modified the Struycken monochord some time ago. He quite recently modified the Edelmann-Galton whistle, and was in the process of calibrating a number of them while I was in his laboratory a few months ago.