In CBCTs which include the cavernous sinuses, just medial and posterior to the back of the orbit lie the internal carotid arteries.
The cavernous part of the artery has a tortuous path which causes turbulance and is more likely to calcify than the straighter portions.
The calcified walls of the artery may be single white lines or parallel lines if both walls are calcified as in this sagittal image.
In coronal images the arteries can appear as opaque circles.
Calcification of the carotid artery walls is a sign of advanced atherosclerotic disease and likely affects other vessels such as coronary arteries.
If you find calcifications, you should advise your patient to consult with their doctor and send a brief letter to the physician.
–Dr Douglas K Benn DDS, PhD, Dipl. Dental Radiology (Royal College of Radiologists, England)
Oral and Maxillofacial Radiologist