Progressive edematous lesions in subacute phase after neuroendovascular therapy.

Background: The appearance of edematous lesions in the subacute phase is a rare complication following neuroendovascular therapy. Effective management of these lesions remains unclear. In this report, a case with progressive edematous lesions in the subacute phase after neuroendovascular therapy was described, and the clinical features and therapeutic strategies were discussed.

Case Description: A 54-year-old female with a large, right cavernous internal carotid artery aneurysm was treated with a flow diverter. Left hemiparesis developed 15 days after the procedure, and multiple edematous lesions in areas of prior catheter procedures were revealed on radiological findings. Steroid pulse therapy was employed, and the lesions were gradually reduced without any additional neurological deficits. No recurrence was recognized in the follow-up study.

Conclusion: In some reports, pathological findings indicate that these lesions result from the presence of foreign bodies, and emboli could be caused by cotton fibers or hydrophilic polymers used as surface coatings on endovascular catheters. In this case, the edematous lesions were most likely caused by hydrophilic polymer emboli. Steroid pulse therapy had a beneficial effect on the lesions. It is important to effectively manage prescribed periods after the procedure to avoid such a rare complication.