A system of practical medicine. By American authors. Vol. 5

by Unknown

I. The Diagnosis of Organic Diseases of the Nervous System.

This should invariably consist, in the observer's mind at least, of three separate diagnoses, each formed by the application of widely different sources of knowledge, and each requiring a different logical process. One diagnosis forms the indispensable preliminary to the others, and the last one, when correct, demonstrates that the neurologist is a physician as well as a specialist. A further utility of this procedure by the method of the threefold diagnosis is, in our opinion, that it constitutes the sure inductive reasoning to be employed in the search after the pathology of new diseases, and must prove of help in the future growth of neurological medicine.

These diagnoses are—

The diagnosis of the symptoms or symptom-group;

The diagnosis of the location of the lesion;

The diagnosis of the nature of the lesion or of the functional disorder.

1. The diagnosis of the symptom or symptom-group is to be made by—(a) careful inquiry into the manner of appearance, development, and chronological order of the symptoms as related by the patient or by his friends, and more especially by (b) an exact, and in some directions minute, determination of the symptoms, obvious or latent, present in the patient. This valuable method of exact observation is sometimes, no doubt, carried to a ridiculous extreme, entailing much loss of time without corresponding results; but in medical practice, as in all forms of professional work, there enters a sort of genius, partly innate, but largely developed by cultivation, which enables the observer to seize at once, apparently by intuition or in the course of a few minutes of study, the really valuable and suggestive phenomena; and it is in this line, the line of important and correlated facts, that observation cannot be too minute and exact. In following this method technical terms must be correctly used and definitions rigidly adhered to, as superficial and loose records nearly always mislead. Sometimes in the course of the examination a symptom is discovered or a hint is thrown out by the patient which suggests new lines of inquiry, and occasionally necessitates an entire rearrangement of the data obtained. Consequently, it is important that the observer should approach a case tabula rasa, and should, as far as possible, prevent his being biassed by anticipations of, and immature guesses at, the third or final diagnosis.

Besides exactness of observation, it is necessary that the physician should have a thorough knowledge of nervous nosology in order to complete the first diagnosis: he must be acquainted by book-study and by personal observation with the numerous types of symptom-groups which fill up our present classification of diseases, so that he can at once say, approximately at least, in what category the case before him belongs.

2. The second diagnosis, that of the location of the lesions, is to be arrived at by the application of the observer's knowledge of the anatomy and physiology of the nervous system; and therefore it is here that special training is of the greatest advantage. The anatomy and physiology of use in this connection are not the bare sciences as taught in ordinary text-books, but a higher sort of knowledge, corrected and extended by the teachings of pathology and pathological anatomy. The physician must be well versed in the recent revelations of experimentation and of autopsies bearing upon the architecture and functions of the central nervous system, and should be able to apply this knowledge deductively to the case in hand. In this manner the now abundant material grouped under the term Localization of Cerebral and Spinal Diseases (vide the next article) can be made of the greatest utility in every-day practice. The solution of the problem of localization of the lesion is much simplified if it be first accurately determined whether the lesion is peripheral, spinal, or cerebral.

3. The final diagnosis is with respect to the nature of the lesion. While the second diagnosis may be said to possess the greater scientific interest, this one must be admitted to possess paramount practical importance, as from it we derive the indications for rational treatment and the data of prognosis. The third diagnosis is to be made by the application of the observer's knowledge of general pathology and etiology; hence it is in this field that the best-trained physician succeeds—where the experienced practitioner may sometimes eclipse the brilliant specialist. The truth of this is maintained by those who hold, as we do, that it is unwise to embark in specialism without having had good hospital advantages and extensive general practice.