Introduction: The natural history of traumatic internal carotid artery (ICA) pseudoaneurysms (Biffl grade III), as well as indications for endovascular or surgical management, are poorly defined.
Methods: Retrospective analysis of blunt cerebrovascular injuries (diagnosed by screening CTA) was performed over a ten-year period at a high-volume trauma center to identify patients with traumatic ICA pseudoaneurysm. Clinical, radiographic and outcomes data were recorded.
Results: Thirty-eight traumatic ICA pseudoaneurysms were diagnosed in thirty-four patients. Pseudoaneurysm location was cervical ICA (84%), cavernous (13%) and supraclinoid (3%). Five patients (13%) developed acute stroke (one watershed and four embolic). Eight or more emboli per hour as detected by daily transcranial Doppler ultrasonography was predictive of embolic stroke (p=0.014). Two of four embolic strokes occurred in patients with cavernous pseudoaneurysms who developed cavernous-carotid fistulae, suggesting concomitant pseudoaneurysm rupture. No cervical ICA pseudoaneurysm ruptured. Three of four patients with embolic stroke were treated acutely, by either parent vessel sacrifice (n=2) or surgical clipping with high flow extracranial to intracranial bypass (n=1).
Thirty-five pseudoaneurysms (92%) were initially treated conservatively with aspirin, of whom 30 (86%) underwent clinical and radiographic follow-up (mean six months). None experienced stroke or hemorrhage, and 23 (77%) pseudoaneurysms were either stable or resolved. Seven (23%) enlarged, five of which had progressive parent vessel stenosis and underwent delayed stenting and/or coiling.
Conclusions: The vast majority of traumatic ICA pseudoaneurysms can be treated conservatively with aspirin and close follow-up. Daily transcranial Doppler ultrasonography with emboli monitoring can identify patients at risk for embolic stroke. Acute endovascular treatment or surgical bypass should be considered in the setting of stroke or rupture. Delayed endovascular treatment is indicated only with progressive pseudoaneurysm enlargement or parent vessel stenosis.
Patient Care: We have shown that ~90% of these lesions can be safely managed with anti-platelet therapy and observation. This is a paradigm shift from previous reports of treating most traumatic ICA pseudoaneurysms in the acute setting with upfront endovascular therapies. After our study, the only indication for upfront endovascular or surgical management of these lesions is embolic stroke or rupture. Lastly we have demonstrated that these untreated lesion can be safely observed without subsequent stroke or hemorrhage risk. If the pseudoaneurysms grow or the parent vessel demonstrates progressive stenosis, delayed intervention is then safe and warranted.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the natural history of internal carotid artery pseudoaneurysm 2) Discuss, in small groups relative indications for upfront endovascular or surgical management 3) Discuss stroke prevention in these patients and the value of transcranial Doppler with emboli monitoring