Concomitant intracranial aneurysm and carotid artery stenosis: a therapeutic dilemma.

Abstract: Concurrent occurrence of carotid artery stenosis and intracerebral aneurysm is uncommon and poses a therapeutic dilemma. We report a patient with bilateral carotid artery stenosis and a 2.5 cm left middle cerebral artery aneurysm who simultaneously underwent a successful stent-assisted coiling for his intracerebral aneurysm and left carotid artery angioplasty with stenting during the same setting.

Key Words: carotid artery stenosis, intracerebral aneurysm, intracranial aneurysm

**********

The occurrence of concomitant intracranial aneurysm and carotid artery stenosis is uncommon and treatment options are limited. We report a patient with a large middle cerebral artery aneurysm and coexistent carotid artery stenosis who underwent a successful carotid endarterectomy with endovascular repair of his aneurysm.

Case Report

A 65-year-old white male presented with bilateral tingling sensation of his hands and face, and altered gait of one day duration that resolved when he reached the hospital. He had a history of diabetes and hypertension for 12 years and his medications included aspirin, metformin and lisinopril. Physical examination, including the neurologic examination, was unremarkable except for a left carotid bruit. His basic laboratory investigations including complete blood count and chemistry profile were normal. Noncontrast CT scan of head showed a mass in the left sylvian fissure suggestive of a thrombosed aneurysm. MRI and MRA of the head revealed a 25 x 24 mm partially thrombosed left middle cerebral artery aneurysm (Fig. 1 and 2). A carotid angiogram revealed a 75% occlusion of the left internal carotid artery and a 50% occlusion of the right internal carotid artery. Since the patient was at high risk for an isolated aneurysm repair or carotid endarterectomy (CEA), he underwent a stent-assisted coiling for his giant left middle cerebral artery aneurysm and left carotid artery angioplasty and stenting during the same setting. Post-stenting angiogram demonstrated the stenting to be in good apposition to the left internal carotid artery wall with 90% occlusion of the aneurysm. At his 6 month follow-up visit, he was asymptomatic and doing well.

Discussion

Incidence of concomitant carotid artery stenosis (CAS) and intracranial aneurysm (ICA) is 3%. The presence of aneurysm is usually an incidental finding and the size of the ICA aneurysm ranges usually from 5 to 10 mm. (1,2) To our knowledge, this is the first published case report of a 25 mm ICA and concomitant CAS.

Patients with concomitant carotid artery stenosis and unruptured ICA pose a difficult management decisions for the physician. While the clipping of the aneurysm first poses the risk of stroke due to decreased blood flow, the correction of carotid stenosis first may result in aneurysm rupture secondary to the increased blood flow. The decision regarding which of these two should be corrected first should balance the risk of the patient developing a stroke against the risk of aneurysmal rupture. However, there are reports of successful outcome of anuerysmal repair in patients undergoing carotid endarterectomy in the presence of ICA <10 mm. (1,3,4) But the outcomes in patients with an ICA >10 mm is uncertain and not widely reported. A decision analysis model suggested clipping of an unruptured ICA in the presence of symptomatic carotid artery stenosis only if the unruptured cerebral aneurysm is the source of the transient ischemic attack. (5) The treatment option for these patients includes clipping the aneurysm before carotid endarterectomy or simultaneous endovascular repair of carotid artery along with coil embolization of cerebral aneurysm or a carotid endarterectomy without aneurysmal repair. (5) ICA could be surgically corrected by either coil embolization technique or open craniotomy with clipping. In a ruptured intracranial aneurysm, endovascular coiling is more likely to result in independent survival at 1 year than neurosurgical clipping and the survival benefit continues for at least 7 years. (6) But clinical trial evidence regarding the benefit of both the procedures is lacking in unruptured aneurysm. In giant ICA, the outcomes may be better with neurosurgical clipping than with coil embolization. (7) In our patient, the aneurysm was large and the decision to repair both stenosis and aneurysm at the same setting by carotid angioplasty with stenting and endovascular coiling was done after discussion with the patient about the risks and benefits of the procedure.

[FIGURE 1 OMITTED]

[FIGURE 2 OMITTED]

Conclusion

The concomitant presence of carotid artery stenosis and intracerebral aneurysm pose a therapeutic dilemma. The decision to correct both at the same setting or one before another should depend on the size of the intracranial aneurysm, the source of the TIA, the presence of locally available expertise and a careful discussion of the risks and benefits of the procedure on an individual basis.

References

1. Kappelle LJ, Eliasziw M, Fox AJ, et al. Small unruptured intracranial aneurysm and management of symptomatic carotid artery stenosis: North American symptomatic carotid endarterectomy trial group. Neurology 2000;55:307-309.

2. Pappada G, Fiori L, Marina R, et al. Incidence of asymptomatic of asymptomatic berry aneurysms among patients undergoing carotid endarterectomy. J Neurosurg Sci 1997;41:257-262.

3. Kann BR, Matsumotot T, Kerstein MD. Safety of carotid endarterectomy associated with small intracranial aneurysms. South Med J 1997;90:1213-1216.

4. Carvi Y. Nievas MN, Haas E, Hollerhage HG. Unruptured large intracranial aneurysms in patients with transient cerebral ischemic episodes. Neurosurg Rev 2003;26:215-220.

5. Dippel WJ, Vermeulen M, Braakman R. Habbema JD. Transient ischemic attacks, carotid stenosis and incidental aneurysm: a decision analysis. Neurosurgery 1994;34:449-458.

6. Molyneux AJ, Kerr RS, Yu LM, et al. International Subarachnoid Aneurysm Trial (ISAT) Collaborative Group.International subarachnoid aneurysm trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: a randomised comparison of effects on survival, dependency, seizures, rebleeding, subgroups, and aneurysm occlusion. Lancet 2005;366:809-817.

7. Terada T, Tsuura M, Matsumoto H, et al. Endovascular treatment of unruptured cerebral aneurysms. Acta Neuroechir Suppl 2005;94:87-91.

Sankar D. Navaneethan, MD, MPH, Vijay Shri Kannan, MD, Ayodele Osowo, MD, Rakesh Shrivastava, MD, and Sonal Singh, MD

From the Department of Medicine, Unity Health System, Rochester, NY, Department of Medicine, Southern Maryland General Hospital, and the Department of Medicine, Wake Forest University, Winston-Salem, NC.

Reprint requests to Sankar D. Navaneethan, MD, MPH, Department of Medicine, Unity Health System, Rochester, NY 14626. Email: [e-mail]

Accepted February 15, 2006.

RELATED ARTICLE: Key Points

* Occurrence of simultaneous intracerebral aneurysm and carotid artery stenosis is uncommon.

* Decision to correct both in the same setting or individually depends on the size of the intracranial aneurysm, the source of the transient ischemic attack, and the presence of locally available expertise.