Contrast-induced Encephalopathy Following Embolization of Intracranial Aneurysms in Hemodialysis Patients

Abstract

Contrast-induced encephalopathy is a very rare complication associated with endovascular treatment of intracranial aneurysms. Patients with renal dysfunction may be prone to developing contrast medium neurotoxicity as a result of delayed elimination of the contrast medium in renal metabolism. This article focuses on our experience with contrast-induced encephalopathy in patients with end-stage renal disease requiring hemodialysis. The authors retrospectively reviewed five patients diagnosed with contrast-induced encephalopathy who underwent aneurysm coil embolization at their institution from January 2006 to December 2015. During the 10-year period, embolization was performed in 755 cases, among which contrast-induced encephalopathy occurred in five patients (0.66%). Three of the five patients were undergoing dialysis for chronic renal failure (one male and two female; mean age 66.7). Embolization for hemodialysis patients was performed in eight during the same period and the incidence of contrast-induced encephalopathy in hemodialysis patients is quite high in our series (3 of 8; 38%). Procedures were performed in one for recurrence of unruptured anterior-communicating artery aneurysm and in two for unruptured basilar-tip aneurysm. Mean approximately 220 ml of contrast media was used among three hemodialysis patients. All three patients showed an improvement or a control in symptoms soon after hemodialysis. Recovery of neurological symptoms was complete in two and almost normal in one within 1 week after intervention. Contrast-induced encephalopathy should be kept in mind as an expected complication of aneurysm embolization in hemodialysis patients. In hemodialysis patients with contrast-induced encephalopathy, performing hemodialysis is an effective treatment to improve symptoms early.

Keywords: contrast-induced encephalopathy; embolization; end-stage renal disease; hemodialysis; intracranial aneurysm.

Fig. 1

Case 1. Left internal carotid angiogram demonstrating recurrence of anterior communicating artery aneurysm (A: three-dimensional reconstruction angiogram and B: conventional angiogram). C: Angiogram acquired after embolization by a stent-assisted technique showing complete occlusion of the aneurysm. D and E: Non-contrast head CT acquired immediately after embolization revealed a cortical contrast enhancement along the sulcus of the bilateral frontal lobes. F and G: Diffusion-weighted image of MRI performed 3 hrs after treatment showing a faint hyper-intense area in the bilateral frontal lobes. H and I: Non contrast CT performed 20 hrs after treatment demonstrating a residual cortical enhancement in the bilateral frontal lobes with edematous changes.

Fig. 2

Case 2. A: Left vertebral angiogram demonstrating an unruptured basilar tip aneurysm. B: Angiogram acquired after embolization by a double catheter technique showing complete occlusion of the aneurysm. C and D: Non-contrast head CT acquired the day after embolization showing a residual cortical enhancement in the bilateral occipital lobes and left thalamus with edematous changes. E and F: Diffusion-weighted image of MRI performed 2 days after treatment showing a hyper-intensity along the sulcus of the left occipital lobe, and faint hyper-intensity in the left thalamus.