It is not to be supposed that the case history and clinical examination, obtained by the methods outlined in the preceding chapter, will complete the investigation of every case. Very often these methods afford but leads to further investigation by special methods according to the indications presenting themselves in the case under consideration. A suspicion of syphilis, for instance, can by no means be definitely dismissed by a denial made either by the patient or other informants; the differentiation between certain alcoholic psychoses, neurasthenia, arteriosclerotic dementia, and other conditions, on the one hand, and general paralysis, on the other, cannot always be made with certainty without the aid of special diagnostic procedures; the intellectual make-up of a patient cannot be determined with any degree of accuracy without resort to measurement by means of the Binet-Simon or other appropriate psychological tests.
Lumbar puncture is a simple and harmless procedure. The only danger, that of infection, can be entirely avoided by the exercise of ordinary precautions of asepsis.
It is, however, contraindicated in cases of great general weakness and in those in which there is evidence of abnormally high intracranial pressure (brain tumor). In such cases there is possibility of fatal issue.1
The examination of cerebro-spinal fluid obtained by lumbar puncture for purposes of psychiatric diagnosis usually consists of the following procedures: (a) cell count to determine presence or absence of pleocytosis, (b) Wasser-mann reaction, (c) chemical tests.
Perhaps of greatest help in diagnosis is the cell count. The number of cells per cubic millimeter of spinal fluid varies considerably both in health and disease, and there is no definite point of demarkation between the two. Most pathologists consider any number under 5 as a negative finding, between 5 and 8 as doubtful, and over 8 as positive.
Where the clinical data would lead the physician to expect a positive finding while the actual finding is doubtful or even negative, the lumbar puncture may be repeated at the end of ten days. Either on first or second examination almost all cases of general paralysis and cerebral syphilis furnish a positive finding; other psychoses furnish, on the contrary, almost invariably a negative one.
The Wassermann reaction has become an important aid, in some cases an indispensable one, in psychiatric diagnosis. It may be applied either to the blood or the cerebro-spinal fluid, or both, and may be of assistance (a) in differentiating psychoses of syphilitic nature from others, (6) to some extent in differentiating general paralysis from cerebral syphilis and from cerebral arteriosclerosis of syphilitic origin, and (c) in judging the effect of anti-syphilitic treatment.
The chemical tests most widely used are Lange's colloidal gold test, Noguchi's butyric acid test, the Ross-Jones ammonium sulphate test and Pandy's phenol test. Their principal object is to determine the presence or absence of excess of certain protein substances in the cerebro-spinal fluid. They serve to differentiate general paralysis, cerebral syphilis, and other conditions associated with inflammatory changes in the central nervous system from conditions, organic or functional, which are not associated with such changes.
1 See Minet and Lavoit. La mort suite de ponction lombaire. L'Echo Medical du Nord, Apr. 25, 1909.
The importance of ascertaining a patient's constitutional make-up has already been pointed out. Anomalies of make-up may be either temperamental or intellectual. For a more accurate study of the latter a system of tests has been devised by Binet and Simon, constituting a measuring scale of intelligence. These tests have been applied to normal children of various ages and have thus been standardized, so that it is now possible by means of them to estimate the degree of mental development of a person in terms of the age at which such development corresponds to the normal average. The authors of these tests have taken special pains to eliminate the disturbing influence of education, having made it their aim to devise a measure of natural mental capacity and not of degree of training.
It should be mentioned that many objections have been raised to the Binet-Simon tests, some of which are directed more against their careless or inexpert use than against the principles on which they are based. On the other hand some inherent weaknesses have also been discovered, and many modifications of the tests have been developed intended to improve them.
Cases of organic brain disease with lesions involving the speech areas and therefore presenting symptoms of aphasia require a special method of examination.
Association tests may be found useful in studying disturbances of flow of thought; they afford a means of measuring mental capacity somewhat like the Binet-Simon tests; and they have been used for the detection of subconscious ideas or complexes.
1G. Aschaffenburg. Experimentelle Studien uber Associationen. Kraepelin's Psychologische Arbeiten, Vols. I, II, and IV. - C. G. Jung. Diagnostische Associaziationsstudien. - Kent and Rosanoff. A Study of Association in Insanity. Amer. Journ. of Insanity, July and Oct., 1910.
Many other tests, both physical and mental, have been more or less thoroughly standardized and are available both for clinical work and for psychiatric research.
The technique of the more commonly employed special diagnostic procedures of the psychiatric clinic will be found in Appendices I to VII in this book.
The psychiatrist - especially one whose practice is mainly institutional - often finds himself in a position unlike that of other medical specialists: he is responsible not only for the diagnosis and management of the nervous or mental disorder which he is called upon to treat, but also, by force of peculiar circumstance, for the general welfare of the patient. If there is any abnormal condition of the eyes, ears, nose or throat; if there are decayed teeth, gynecological trouble, or surgical conditions requiring intervention; or if there is anemia, tuberculosis, diabetes, nephritis, heart disease, intestinal worms, or what not, he must see to it that they are brought to light and their nature exactly determined, and that they are submitted to appropriate treatment and as far as possible remedied.
He cannot, of course, be proficient in all medical specialties, but he can and should organize his clinical work in such a way as to be able to readily avail himself of consultation with other specialists whenever necessary.
1 G. M. Whipple. Manual of Mental and Physical Tests. Second edition. Baltimore, 1915. - Woodworth and Wells. Association Tests. Psychol. Monographs, No. 57, Dec, 1911. - S. I. Franz. Handbook of Mental Examination Methods. Second Edition, New York, 1919.