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

Fatal complications after myelography with meglumine diatrizoate

A case of inadvertent intrathecal injection of diatrizoate meglumine is presented. After myelography with 10 ml i.e. 6.5 g Angiografin, a 76-year-old man rapidly developed myoclonus, drowsiness and excessive metabolic acidosis. He died only a few hours later. Postmortem showed non-specific brain edema. RP-HPL-Chromatography confirmed high concentration of the contrast medium in CSF (6 mg/ml) which must have induced refractory central nervous dysregulation. The lethal effects of the misapplication of this agent on the nervous system are discussed.

Lateral C1-C2 puncture: a technique to reduce adverse reactions in metrizamide sellar cisternography

Fifteen metrizamide sellar cisternograms performed with lateral C1-C2 puncture are presented. The technique is explained and adverse reactions are compared with those reported in cisternograms performed with lumbar injection. Attention is drawn to the simplicity of the method, the small amount of contrast medium required and the few and mild adverse reactions.

Metrizamide cisternography and computed tomography for the investigation of pituitary lesions

Metrizamide cisternography and computed tomography (CT) have been performed on 22 patients suspected of having pituitary or suprasellar lesions, using a low dose of metrizamide. These patients would otherwise have been subjected to air encephalography. The technique is described and the results are presented. The lesions demonstrated included empty sellae and suprasellar extensions of pituitary tumours. We also identified those patients in whom there was no suprasellar extension of a pituitary tumour. The diagnostic information required was obtained in all cases by a combination of the two techniques and air encephalography was avoided in all but one case. The side effects were mild and no serious complications were encountered. We consider this combination of methods to be very useful for the investigation of pituitary lesions.

Studies of the third circulation. Amipaque CT cisternography and ventriculography

The techniques of Amipaque (metrizamide) computerized tomography (CT) cisternography and Amipaque CT ventriculography are described. Normal, intermediate, delayed, and obstructive cerebrospinal fluid circulation patterns are readily demonstrated by evaluation of ventricular stasis of Amipaque on serial CT scans. Both the morphological and physiological characteristics of intracranial cysts are accurately defined and a diagnostic classification is presented. The functional integrity of ventricular shunts can be appraised using the ventricular persistance of Amipaque as a primary criterion. Other applications of these modalities are described and their place in the neurodiagnostic armamentarium is discussed.

Potentiation of Amipaque epileptogenic activity by neuroleptics

Experiments conducted on rabbits confirmed that chlorpromazine potentiates the weak epileptogenic action of Amipaque (metrizamide). Chlorpromazine withdrawal for a period of 48 h suppresses this potentiating effect in the rabbit. Neuroleptic drugs should therefore be avoided in patients examined with Amipaque. In patients under chronic treatment, neuroleptics ought to be discontinued at least 48 h before examination with Amipaque. With the doses and methods used in the present study, diazepam was not as effective as phenobarbital in preventing epilepsy produced by Amipaque. When premidication is needed or when convulsions occur after Amipaque examinations, combined diazepam and phenobarbital therapy ought to be instituted in order to achieve the best control of epileptic reactions.

Cerebrospinal fluid imaging using serial metrizamide CT cisternography

Twenty-five patients studied by serial metrizamide (Amipaque) CT cisternography were used to analyze CSF kinetics. Delayed CSF flow patterns were noted in 7 patients, while intermediate patterns occurred in 4. The abnormal cisternogram was characterized primarily by ventricular reflux and stasis and secondarily by diminution of the parasagittal blush and a periventricular rim of decreased absorption. The intermediate group had minimal ventricular stasis after 24 hours and a normal parasagittal blush. After clinical and biochemical evaluation of the patient with dementia, CT scanning is usually indicated. If a profile suggestive of communicating hydrocephalus emerges, CSF kinetics can be monitored dynamically by CT scanning with metrizamide enhancement.