The determination of the refractive index of blood has been in use for several years owing to the work of Reiss,1 Naegeli,2 Rohrer3 and many others. It seemed to us worth while to determine the refractive index of cerebrospinal fluid. The literature reviewed by us revealed so far only two references to such determinations, the work of Polanyi4 and that of Molnar.5 It was our hope that the refractive index of cerebrospinal fluid in various conditions might yield some data that would be found useful for diagnosis, as has been the case in blood.1 In order to do the work along the same lines as has been done on blood, it was deemed advisable to do viscosimetric readings together with refractometric determinations. It also was hoped that the combination of the two, the refractometric and the viscosimetric indexes, might throw light on the albumin-globulin ratio of cerebrospinal fluid.
LEVINSON A, SERBY AM. THE REFRACTOMETRIC AND VISCOSIMETRIC INDEXES OF CEREBROSPINAL FLUID. Arch Intern Med (Chic). 1926;37(1):144-150. doi:10.1001/archinte.1926.00120190147013