Microembolic Signal Monitoring after Coiling of Unruptured Cerebral Aneurysms: An Observational Analysis of 123 Cases

The case of a patient on clopidogrel with a large, broad-based, left-sided ophthalmic aneurysm is presented (A). A stent was placed across the neck of the aneurysm (B; left, dotted arrow); however, only incomplete embolization could be achieved (B; middle and right, full arrows). The procedure was uneventful; no focal neurologic deficits were noted after procedure. However, the patient then developed severe agitation and refused heparinization. The next morning, the patient presented with new receptive aphasia and a profound weakness of her right upper and lower extremity. Follow-up MES monitoring performed at this time (12 hours after the procedure) showed 72 MESs/hr, indicating that antiplatelet agents alone may not suffice early after this particular intervention. When we were able to initiate the heparin drip later on, repeat MES monitoring 6 hours later showed a reduction to 12 MESs/hr, but unfortunately, CT already confirmed multiple areas of embolic infarction (C; left, dotted arrows), which also were demonstrated by MR imaging later that day (C; middle and right, full arrows).