Diffuse Cerebral Edema After CT Myelography Causing Focal Neurological Symptoms

Abstract

Adverse effects of nonionic contrast agents are rare. We present a case of diffuse cerebral edema and neurological deficits after computed tomography (CT) myelography that resolved without specific intervention.An 80-year-old woman presented with left-sided weakness, left facial droop, and slurred speech. Two days prior, she underwent CT myelography for evaluation of her lower back pain. Twelve milliliters of iohexol (Omnipaque 180 mgI/mL; GE Healthcare, Pittsburgh, Pa) were injected into the L3-L4 interlaminar lumbar space using a 22-gauge spinal needle with the patient in prone position. She was taking 5 mg of apixaban twice daily for atrial fibrillation, which was discontinued 5 days prior to the procedure and restarted afterward. The dysarthria started the night prior to admission, followed by left-sided hemiparesis and left facial droop. Her medical history included nonischemic cardiomyopathy, hypertension, and a left parietal stroke 2 years earlier, without residual deficit. A biventricular implantable cardioverter-defibrillator was in place. Her medications include losartan, carvedilol, furosemide, levothyroxine, and pregabalin. Physical examination revealed partial flattening of the left nasolabial fold with sparing of the forehead, left grip strength weaker than the right, 4/5 strength in the left upper and left lower extremities, and normal strength in the right upper and lower extremities. Aside from an estimated glomerular filtration rate of 51 mL/min/1.73m 2 , laboratory studies and electrocardiography were unremarkable. CT of the head showed diffuse cerebral edema with gyral swelling and loss of sulci, effacement of the basal cisterns, and hypoattenuation of the cerebral white matter. There was no intracranial hemorrhage or shift. The presence of the implantable cardioverter-defibrillator precluded magnetic resonance imaging. The initial concern was for a multifocal embolic stroke. However, her signs and symptoms completely resolved gradually over the next 48 hours. Repeat brain CT 2 days after the onset of her symptoms showed marked improvement of the cerebral edema and resolution of the white matter hypodensities. She was discharged on her fourth hospital day with no residual neurological deficits.