Polymer degradation rates and persisting brain lesions post endovascular procedures.

Polymer coating emboli have been affiliated with persisting brain lesions after endovascular procedures.1–6 Patient symptoms include headaches, fevers, chills (ie, constitutional symptoms), neurological presentations of focal weakness, sensory and visual deficits, and seizures. Follow-up imaging highlights distinct areas of contrast enhancement in slightly different locations, with some lesions increasing in number and size (see figure 1). Polymer particles from various coating compositions have different rates of degradation, absorption, and metabolism or excretion (DAM/E). These varied rates of DAM/E may have impacts on persisting brain lesions, recurrent patient symptoms, and adverse event outcomes. Figure 1 Characteristic MRI of patients with persisting brain lesions. T1 postcontrast images highlighting an increase in the number and size of lesions (white arrows) over a 12 month period. Also note formation of new enhancing lesions. Images used with permission by Williams and Wilkins Co. (license ID: 1100407-1). Degradation is the chemical breakdown of a polymer by hydrolysis, oxidation, or enzymatic processes. A faster degradation rate may result in less obstruction within blood vessels or reduced presence …