Ruptured Giant Left Paraclinoid Internal Carotid Artery Aneurysm in a Patient with Right Aortic Arch Managed with Staged Endovascular Coiling and Flow Diversion

Background: Giant cerebral aneurysm occurring in the setting of right sided aortic arch (RAA) is exceedingly rare.

Case Description: A 56 years old female presented with acute headache. MRI of her brain showed subarachnoid haemorrhage (SAH) and a left internal carotid artery (LICA) paraclinoid segment giant aneurysm. During catheter angiography she was noted to have RAA. The left common carotid artery arose from the aortic arch with a very acute angle. Partial coiling of the LICA giant aneurysm was performed using a 6F guiding catheter with an inner 5F catheter with SIM curve in order to navigate the acute angle. Flow diverter was inserted three weeks later under double antiplatelet cover. Follow up angiogram at 6 months showed complete occlusion of the aneurysm.

Conclusion: cerebral aneurysms can be treated successfully with endovascular approach despite difficult and unpredictable anatomy in the rare situation of concurrence of RAA.

Keywords: right aortic arch, giant cerebral aneurysm.