Morphometric examination of the styloid process by 3D-CT in patients with Eagle syndrome.

Purpose: This study aimed to obtain the length, medial-anterior angulation and basis-apex coordinates of the styloid process in patients with Eagle syndrome by three-dimensional computed tomography.

Methods: This study was performed on three-dimensional computed tomography images obtained from the hospital picture archiving and communication system (by obtaining 3D images by a RadiAnt DICOM viewer 4.6.9 version). In this study, the anterior and lateral lengths of the styloid process, its anterior and medial angulation, and the coordinate values on the x, y, and z-axes of 24 patients (14 males, 10 females) diagnosed with Eagle syndrome were examined.

Results: The mean anterior lengths were found to be 41.45 mm on the right and 36.07 mm on the left sides, while the mean lateral lengths were found to be 42.15 mm on the right and 37.59 mm on the left sides. The mean medial angulation was measured to be 62.91° on the right and 63.42° on the left, while mean anterior angulation was measured to be 28.01° on the right and 30.43° on the left. The styloid process basis coordinates were determined as (right: x = - 41.30, y = 0, z = 0, left: x = 40.79, y = 0, z = 0), and apex coordinates were determined as (right: x = - 22.61, y = - 36.86, z = - 19.52, left: x = 24.90, y = - 32.14, z = - 18.65).

Conclusion: Knowing the styloid process basis and apex coordinates in addition to knowing the its length and angulation will be useful in diagnosing Eagle syndrome. We think that these results in relation to the coordinates of the styloid process will bring a new perspective to clinicians who investigate the length and angulation of the styloid process.