CTA and CT perfusion was luckily performed with the patient's head rotated to the right (not intentional). This demonstrated occlusion of right ICA by calcified stylohyoid ligament. CTP demonstrated correlative cerebral hypoperfusion (although this did not account for the patient's apparent right hemiparesis, which was confirmed with the referring doctor).

Delayed phase post contrast CT brain was subsequently performed with the patient's head in neutral position. This demonstrated patent right ICA at and above level of calcified stylohyoid ligament.

Conclusion:

Eagle syndrome with compression of right ICA.

Acknowledgement: A/Prof Ronil Chandra (Neurointerventional Radiologist)