Embolic agent useful in pediatric neurovascular lesions

By Eleanor McDermid, Senior medwireNews Reporter

Researchers report a low permanent morbidity rate when using the liquid embolic agent Onyx to treat cranial and spinal vascular lesions in children.

"Although the overall rate of complications (23.8%) was higher than expected, most of them either were clinically silent or had only transient clinical effect," say Mohammad Ali Aziz-Sultan (University of Miami Miller School of Medicine, Florida, USA) and co-workers.

"Thus, our initial experience suggests that Onyx [ev3 Neurovascular, Irvine, California, USA] embolization can be performed in children for a diverse group of vascular lesions with low overall permanent morbidity."

The rate of permanent morbidity was just 1.9% and no patient died, they report in Neurosurgery.

Of the 69 children in the study, who underwent 105 procedures using Onyx, two developed permanent neurologic deficits. One of these two patients had an arteriovenous malformation (AVM) and developed deficits resulting from nontarget embolization; the other had a cerebral aneurysm and developed an infarct in the embolization territory.

The most common complication was infarction in the embolization territory, occurring in six children, followed by microcatheter-related vessel perforation, which occurred in three children. Other complications included hemorrhage (intraparenchymal and intraventricular), cerebral-to-pulmonary-artery embolization, edema, and a retained microcatheter.

Overall, the rate of periprocedural ischemic and hemorrhagic complications was similar to that reported in adults, notes the team.

No factor from a range including age, gender, AVM grade, and procedural variables predicted complications.

Three-quarters of the patients had primary vascular lesions - mostly AVMs - and the other patients had various types of tumor. All but two of the complications occurred in patients with vascular lesions.

"We favor staged embolization of complex lesions, especially in pediatric patients, to limit both the contrast dose and the radiation exposure," comment Aziz-Sultan et al. "Additionally, we believe that less dramatic alterations in cerebral hemodynamics, achieved through staged embolization, result in lower potential for morbidity."

In particular, the researchers believe staged embolization can help to reduce hemorrhage risk. They also suggest measures to avoid the other complications they encountered, such as adjunctive flow reduction to avoid nontarget embolization; and antiplatelet therapy, if appropriate, and support of blood pressure to avoid ischemic complications.

Licensed from medwireNews with permission from Springer Healthcare Ltd. ©Springer Healthcare Ltd. All rights reserved. Neither of these parties endorse or recommend any commercial products, services, or equipment.