Seizures after intravenous contrast media for cranial computed tomography.

Abstract

SUMMARY Patients who had contrast medium-induced seizures were reviewed retrospectively in a consecutive series of 15,226 contrast-enhanced head CT examinations. An incidence of 0 19% was found. There was a strong association with a history ofspontaneous seizure and with the presence ofa structural intracranial abnormality. The contrast medium-induced seizures were short-lived and selflimiting or readily controlled with small doses of intravenous diazepam. They were clinically benign.Seizures are rare after intravenous injection of iodinated radiographic contrast media. In patients undergoing excretory urography an incidence of 0-001-0-0 I% has been reported. '-3 Patients who have computed tomography (CT) of the brain might be expected to have a higher incidence of seizure because epilepsy and structural lesions which lower the seizure threshold are more common in this selected group. An incidence of0 5% was found in two series.45 The risk of seizure is particularly high in patients with cerebral metastatic disease undergoing contrast-enhanced CT, in whom an incidence of 6-19% is reported.'In the General Infirmary at Leeds we have used a greater variety of contrast media in a wider range of osmolalities and doses than has been previously reported in series of contrast-enhanced cranial CT examinations. Fisher's exact two-tailed test was used to assess the significance of the variations in seizure incidence.The technique of contrast medium injection varied little between patients. For adults a 19 gauge butterfly needle was inserted in an arm vein and contrast medium was injected as rapidly as possible by hand, in practice taking 2-3 minutes for injections of 100 ml. After injection patients were observed continuously for 30 minutes by a senior radiographer. In the event of a seizure a radiologist was called promptly to attend the patient. Seizures were treated with intravenous diazepam (Valium, Roche) at the discretion of the attending radiologist.The patients' medical records and CT scans were reviewed to determine; (1) the type and duration of the contrast medium-induced seizure; the dose and concentration of the contrast medium used; the time ofseizure onset after contrast injection and whether the seizure was self-limited or lasted sufficiently long to require treatment, in the view ofattending medical staff. (2) The type and duration of previous seizures.

Contrast-Induced Neurotoxicity following Cardiac Catheterization

“…We speculate that patient's blood brain barrier in the right hemisphere might impaired by small ischemic strokes from microemboli occurring during the cardiac catheterization or from her underlying carotid stenosis. Additionally, she had received a very high dose of contrast and had baseline impaired kidney function [12], that likely resulted in an unusually high concentration of contrast to the brain with subsequent neurotoxicity: a large dose of contrast (regardless of osmolality) itself can cause disruption of the blood brain barrier and neurotoxicity in the absence of underlying brain pathology [12, 13]. Finally, the patient had a previous history of transient cortical blindness after cardiac catheterization which may also be associated to CIN as well.…”

Focal seizure with transient asymmetrical cortical and subarachnoid enhancement on computed tomography following iodinated contrast administration

“…Iodinated contrast is a rare precipitant of seizures, with an incidence of 0.19% in one series 1 . The risk was higher in patients with pre-existing epilepsy and/or intracranial pathology.…”

Myocardial infarction, seizure and an abnormal head CT scan

“…Contrast agent neurotoxicity presenting with focal seizures with CT head findings similar to subarachnoid haemorrhage has also been reported 9. Contrast- medium-induced seizures are well described in the literature and their incidence has been reported to be about 0.2–0.5% 10. They are typically self-limiting and do not require prolonged anticonvulsant treatment.…”