Introduction Aneurysms of the petrous segment of the internal carotid artery are rare, usually asymptomatic but may present with a variety of symptoms.

Treatment options include medical, surgical and endovascular treatment.

Aim of Study To present a case of giant saccular aneurysm of petrous segment of internal carotid artery manifested with a cerebral ischemia and treated with flow diverter and coils placement.

Methods A 49 years old male patient was admitted to the hospital with right sided hemiparesis and dysarthria.

MR exam showed multiple acute ischemic focal lesions in the left centrum semiovale and basal ganglia and giant partially thrombosed left ICA petrous segment aneurysm. Double anti-aggregation treatment was initiated.

Three weeks later patient was shifted to our hospital. CTA confirmed existence of the aneurysm and remodeled petrous bony carotid canal and erosive changes of clivus.

The decision was made for endovascular treatment.

Flow diverter (4 mm x 35 mm) was placed over the neck of the aneurysm and 8 coils detached inside the aneurysm. Angiographic follow up showed stagnation of contrast media inside the aneurysm.

Double anti aggregation therapy was continued and corticosteroid applied for 9 days.

Results Follow up MR done 3 and 8 months after intervention, showed chronic left cerebral focal infarctions and complete exclusion of the aneurysm. Angiographic study done 11 months after intervention showed complete exclusion of the aneurysm.

Conclusion Endovascular treatment using flow diverter with additional coiling seems to be the first choice of treatment in selected patients with petrous segment carotid aneurysms.

Disclosure of Interest Nothing to disclose