Spontaneous thrombosis and calcification of giant cavernous carotid artery aneurysm: A rare case and management insights.

BACKGROUND: Giant cavernous carotid artery aneurysms (>25 mm) are rare (3-5%), with some prone to spontaneous thrombosis (10-20% complete). We present a unique case of one of the largest aneurysms spontaneously thrombosing and calcifying.

CASE DESCRIPTION: A 57-year-old with persistent right-sided headaches had a substantial hyperdense mass in the right middle cranial fossa, eroding petrous bone. Magnetic resonance imaging and digital subtraction angiography revealed a giant cavernous segment fusiform aneurysm of the right internal carotid artery (ICA) with spontaneous thrombosis and distal ICA occlusion. Collateral circulation maintains the cerebral blood supply. Despite anatomical challenges, conservative management was chosen due to the patient's stability.

CONCLUSION: This case highlights the complex interplay between thrombosed giant aneurysms and affected vessels, with unique features such as cross-flow, calcification, and bone erosion. We advocate conservative management for stable cases, supported by literature, emphasizing vigilant follow-up. This expands the spectrum of aneurysm presentations and encourages further research into their dynamics.