Reversible Acute Onset Coma Following Iodinated Contrast Agent During Carotid Angioplasty And Stenting: Unusual Case Report

Abstract

Contrast-induced encephalopathy (CIE) is a rare complication of angiographic contrast use that occurs
during or after in various angiographic procedures and can result in a range of neurological symptoms.
Important diagnostic radiological signs include brain edema and cortical enhancement. Neurotoxicity
appears to be due to disruption of the blood-brain-barrier by the high osmolarity of the contrast agent.
Here, we present a case of transient contrast encephalopathy “coma of unknown etiology” following
carotid angioplasty and stenting (CAS). A 78-year-old right-handed man soon after the procedure
of CAS, he developed rapidly aphasia and right faciobrachial hemiparesis. Immediately following
neurological focal event, the patient developed psychomotor agitation and delirium. The patient
subsequently developed a state of coma. The total amount iomeprol intravascular administered during
the procedure was of 190 ml. An emergency nonenhanced CT showed bilateral cortical enhancement
and edema in the left cerebral hemisphere. On the second post-procedure day, the patient was transferred
to the intensive care unit. Fortunately, her clinical manifestations disappeared gradually, and the patient
recovered with complete resolution of contrast enhancement after seven days of conservative treatment.
The patients received IV hydration, IV mannitol as part of is treatment protocol. Urgent neuroimaging
is important to obtain the correct diagnosis and treated with supportive management as soon as possible.
This is an unusual report of neurotoxicity mimicking massive vascular causes of coma clinically. The
findings suggest that CIE should be considered in the differential diagnosis if any acute neurological
symptoms are noted during and immediately after of angiography examinations. To our knowledge, the
development of prolonged coma by neurotoxicity cause, after application of intravascular radiographic
contrast is a rare complication of endovascular treatment. This case highlights that severe symptom can
persist for many days after endovascular intervention. A high index of suspicion should be maintained
for patients with angiographic procedures and rapidly developing neurological deterioration postprocedure.
We herein report a case of prolonged coma following procedure of CAS. This case illustrates
the diagnostic challenges for a patient that they fall into a coma because of angiographic procedures and
raises awareness for CIE as an exclusion diagnosis.