Delayed Leukoencephalopathy: A Rare Complication after Coiling of Cerebral Aneurysms

Abstract

Background and purpose: Delayed leukoencephalopathy is a rare complication that occurs after endovascular coiling of cerebral aneurysms. We aimed to describe a clinical picture of delayed leukoencephalopathy and explore potential associations with procedural characteristics.

Materials and methods: We considered endovascular coiling procedures for cerebral aneurysms performed between January 2006 and December 2017 in our institution with follow-up MRIs. We used logistic regression models to estimate the ORs of delayed leukoencephalopathy for each procedural characteristic.

Results: We reviewed 1754 endovascular coiling procedures of 1594 aneurysms. Sixteen of 1722 (0.9%) procedures demonstrated delayed leukoencephalopathy on follow-up FLAIR MR imaging examinations after a median period of 71.5 days (interquartile range, 30-101 days) in the form of high-signal changes in the white matter at locations remote from the coil mass. Seven patients had headaches or hemiparesis, and 9 patients were asymptomatic. All imaging-associated changes improved subsequently. We found indications suggesting an association between delayed leukoencephalopathy and the number of microcatheters used per procedure (P = .009), along with indications suggesting that these procedures required larger median volumes of contrast medium (225 versus 175 mL, OR = 5.5, P = .008) as well as a longer median fluoroscopy duration (123.6 versus 99.3 minutes, OR = 3.0, P = .06). Our data did not suggest that delayed leukoencephalopathy was associated with the number of coils (P = .57), microguidewires (P = .35), and guiding systems (P = .57).

Conclusions: Delayed leukoencephalopathy after coiling of cerebral aneurysms may have multiple etiologies such as foreign body emboli, contrast-induced encephalopathy, or hypersensitivity reaction to foreign bodies.

FIG 1.

Flow diagram of procedure inclusion.

FIG 2.

An illustrative case with left ICA aneurysm post-endovascular coiling (patient 11). The aneurysm size is >17 mm in maximum diameter (A), and endovascular coiling was successfully performed using the double-microcatheter technique (B). After 55 days, right weakness developed and broad high-signal change in the left parieto-occipital region is detected on a FLAIR image (C). In the same region, there is a scattered contrast effect (D) and low spotty regions in the SWI (E). The patient was hospitalized and treated with steroid pulse therapy, and the symptoms and image abnormality subsequently improved.