Cervical carotid artery dissection is associated with styloid process length

Area of Science:

• Anatomy
• Vascular Surgery
• Radiology

Background:

• Cervical carotid artery dissection (CCAD) is a significant cause of stroke.
• The anatomical factors contributing to CCAD are not fully understood.
• The styloid process of the temporal bone is a potential anatomical risk factor.

Purpose of the Study:

• To investigate the association between cervical carotid artery dissection (CCAD) and the anatomical characteristics of the temporal bone's styloid process.
• To determine if styloid process morphology correlates with CCAD risk.

Main Methods:

• CT angiograms of 38 patients with CCAD and 38 matched controls were analyzed.
• Styloid process length, angulation, and proximity to the carotid artery were measured bilaterally by blinded raters.
• Statistical analysis was performed to compare measurements between case and control groups.

Main Results:

• While control subjects showed significant bilateral symmetry in styloid process measurements, CCAD patients exhibited a significantly longer styloid process on the side of dissection compared to controls.
• Increasing styloid process length was significantly associated with an increased odds ratio for carotid dissection.
• Patients in the highest quartile of styloid process length had a four-fold increased odds of dissection.

Conclusions:

• A longer styloid process is significantly associated with cervical carotid artery dissection (CCAD).
• These findings suggest that mechanical irritation or injury from an elongated styloid process may play a role in the pathogenesis of CCAD.
• This highlights the importance of evaluating styloid process anatomy in patients with CCAD.