Greater occipital nerve sonographic anatomy and its relationship with headaches

This study aims to supplement information about sonographic anatomy of the greater occipital nerve (GON). In addition, we are studying the relationship between anatomy, gender, body mass index (BMI) and headache incidence.

The study was conducted on 30 adult patients. Anthropometric data, health and headache occurrence information were collected from the participants. The ultrasonographic measurements were taken at two locations: the distal (height of the superior nuchal line), and the proximal (level of the second cervical spinous process) on both sides. In the group of patients where the GON was present at the proximal location, we examined if there were any significant differences in transverse and vertical diameter, circumference, depth, cross-sectional area (CSA), and the distance between the C2 spinous process and the GON between males and females. Additionally, we investigated correlation between the CSA and BMI and evaluated the group of patients with the GON present bilaterally to determine if there were any differences in CSA and CSA/BMI between patients who experienced headaches for at least 10 days in a 3-month period and those who had headaches lasting for less than 10 days.

The research included 20 females and 10 males, of which two female participants were excluded from the further analysis, because they did not provide relevant information regarding their health. We were able to visualize the nerve (on at least one side) in 24/28 (85.7%) patients at the proximal location and 7/28 (25%) at the distal location (in two patients the nerve was branching). No significant differences were found between male and female patients in most measurements, except for nerve depth (P = 0.0003), which was found to be greater in males. There was no correlation between GON cross-sectional area and BMI (r = 0.004, P = 0.98). Patients with bilaterally visible GON and headaches present for at least 10 days within 3 months showed larger CSA and CSA/BMI values (P = 0.046 and P = 0.033 respectively).

This study provides insights into the sonographic anatomy of the GON and its association with headaches, highlighting the potential for diagnostic applications of the GON sonography.