Absorption of labelled metrizamide, diatrizoate, inulin and water from cerebrospinal fluid to blood. A pharmacokinetic investigation in cats with normal and impaired renal function

The rate of CSF formation in man: preliminary observations on metrizamide washout as a measure of CSF bulk flow

Metrizamide, a nonionic, water-soluble contrast agent, was injected into the ventricular system of 3 patients with indwelling ventricular catheters and subcutaneous cerebrospinal fluid reservoirs. A first-order rate constant, k, for metrizamide washout from the right lateral ventricle was determined with reference to mean ventricular metrizamide concentration on serial CAT scans; right ventricular volume, V, was estimated after metrizamide injection by multiplying the appropriate ventricular area on consecutive CAT slices by the nominal slice thickness. The rate of right lateral ventricular CSF formation, If, in our 3 patients was calculated as k X V and ranged from 0.083 to 0.103 ml per minute.

Results of the use of a new water-soluble contrast medium (metrizamide) in the posterior fossa of the baboon

An investigation was made of the use of a new water-soluble contrast material (metrizamide) for posterior-fossa radiography in the baboon. The experiments showed that the concentration of metrizamide needed to produce adequate radiographs from sub-occipital injections into the posterior fossa always produced generalized seizures. Intraventricular injection produced excellent radiographs from metrizamide concentrations, which did not result in either clinical or EEG seizure activity. Seizures, when they occurred, were easily controlled with pentobarbitone and phenytoin. In all the experiments, ECG changes were found, which disappeared after some hours.