Sonographic evaluation of the greater occipital nerve in unilateral occipital neuralgia.
OBJECTIVE
Occipital neuralgia is a headache that may result from greater occipital nerve entrapment. Entrapped peripheral nerves typically have an increase in cross-sectional area. The purpose of this study was to measure the cross-sectional area and circumference of symptomatic and asymptomatic greater occipital nerves in patients with unilateral occipital neuralgia and to correlate the greater occipital nerve cross-sectional area with headache severity, sex, and body mass index.


METHODS
Both symptomatic and contralateral asymptomatic greater occipital nerve cross-sectional areas and circumferences were measured by a single examiner using sonography in 17 patients. The Wilcoxon signed rank test and Spearman rank order correlation coefficient were used to analyze the data.


RESULTS
Significant differences between the cross-sectional areas and circumferences of the symptomatic and asymptomatic greater occipital nerves were noted (P < .001). No difference existed in cross-sectional area (P = .40) or circumference (P = .10) measurements of the nerves between male and female patients. A significant correlation existed between the body mass index and symptomatic (r = 0.424; P = .045) and asymptomatic (r = 0.443; P = .037) cross-sectional areas. There was no correlation shown between the cross-sectional area of the symptomatic nerve and the severity of Headache Impact Test 6 scores (r = -0.342; P = .179).


CONCLUSIONS
We report sonographic evidence showing an increased cross-sectional area and circumference of the symptomatic greater occipital nerve in patients with unilateral occipital neuralgia.
Department of Radiology, Logan College of Chiropractic, Chesterfield, MO 63107, USA. johncscho@hotmail.com
John Chin-Suk
JC
Cho
Daniel W
DW
Haun
Norman W
NW
Kettner
D000328:Adult; D015992:Body Mass Index; D005260:Female; D006261:Headache / Q000150:complications / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D009437:Neuralgia / Q000150:complications / Q000000981:diagnostic imaging*; D009777:Occipital Bone / Q000000981:diagnostic imaging* / Q000294:innervation*; D010525:Peripheral Nerves / Q000000981:diagnostic imaging*; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D014463:Ultrasonography; D055815:Young Adult