The Measurement of Glomerular Filtration Rate with125-Sodium Iothalamate (Conray)

Abstract
Simultaneous renal clearances of 125j-iothalamate and inulin were performed in 10 patients. The mean 125i-iothalamate-to-inulin clearance ratio was 1.018. In 2 patients, the clearance of 131I-iothalamate was similar to that of the 131j form which is known to be excreted by glomerular filtration only. 125i-iOthalamate provides an accurate measurement of glomerular filtration rate in man.