Abstract
The paper describes a modification of the constant infusion method in which filtration rates as low as 25 per cent of the normal can be measured with the same dosage of inulin and without collecting the urine. The theoretical basis is reviewed, and a comparison is made with the results calculated on the basis of collection of urine. With a view to the applicability of the method in patients with ureterocolic anastomosis, it has been ascertained that reabsorption of inulin from the intestine will not take place to an extent involving any errors.