Transcranial magnetic stimulation (TMS) is a noninvasive activation method that is increasingly used for motor mapping. Preoperative functional mapping in vascular surgery is not routinely performed; however, in cases of high-grade arteriovenous malformations (AVMs), it could play a role in preoperative decision making. A 16-year-old male was suffering from a giant, right-sided insular, Spetzler-Martin Grade V AVM. This patient's history included 3 hemorrhagic strokes in the past 3 years, resulting in Medical Research Council Grade 2-3 (proximal) and 2-4 (distal) paresis of the left side of the body and hydrocephalus requiring a ventriculoperitoneal shunt. Preoperative TMS showed absent contralateral innervation of the remaining left-sided motor functions. Subsequently, the AVM was completely resected without any postoperative increase of the left-sided paresis. This case shows that TMS can support decision making in AVM treatment by mapping motor functions.
Keywords: AChA = anterior choroidal artery; AVM = arteriovenous malformation; EVD = external ventricular drain; GCS = Glasgow Coma Scale; HS = hemorrhagic stroke; ICA = internal carotid artery; MCA = middle cerebral artery; MEG = magnetoencephalography; MRA = MR angiography; MRC = Medical Research Council; PCA = posterior cerebral artery; TMS = transcranial magnetic stimulation; VP = ventriculoperitoneal; arteriovenous malformation; brain mapping; eloquent area; fMRI = functional MRI; microsurgical resection; outcome; pediatric hemorrhagic stroke; vascular disorders.