Neurite Damage in Patients with Migraine.

We examined neurite orientation dispersion and density imaging in patients with migraine. We found that patients with medication overuse headache exhibited lower orientation dispersion than those without. Moreover, orientation dispersion in the body of the corpus callosum was statistically negatively correlated with migraine attack frequencies. These findings indicate that neurite dispersion is damaged in patients with chronic migraine. Our study results indicate the orientation preference of neurite damage in migraine.

Brain Microstructure and Brain Function Changes in Space Headache by Head-Down-Tilted Bed Rest.

INTRODUCTION: Several astronauts have experienced severe headaches during spaceflight, but no studies have examined the associated brain microstructure and functional changes. Head-down-tilted bed rest (HDBR) is a well-established method for studying the physical effects of microgravity on the ground. In this study, we analyzed the changes in brain microstructure and function during headache caused by HDBR using diffusion tensor imaging (DTI) and resting state functional magnetic resonance imaging (R-fMRI).METHODS: We imaged 28 healthy subjects with DTI and R-fMRI in the horizontal supine position and HDBR. Using Tract-Based Spatial Statistics, fractional anisotropy, mean diffusivity, radial diffusivity, and axial diffusivity were compared between the headache and non-headache groups. Additionally, an analysis of functional connectivity (FC) was performed, followed by a correlation analysis between FC and numerical rating scale.RESULTS: HDBR caused headaches in 21 of 28 subjects. DTI analysis showed no significant change in fractional anisotropy after HDBR, whereas axial diffusivity, radial diffusivity, and mean diffusivity increased significantly. R-fMRI analysis showed a significant decrease in FC in several areas after HDBR. The headache group showed significantly higher FC before HDBR, and both groups showed higher FC after HDBR. Correlation analysis showed a positive correlation between FC and numerical rating scale before HDBR but negative after HDBR.DISCUSSION: We demonstrated the image change in the acute phase of space headache by HDBR using DTI and R-fMRI. Changes in brain microstructure and function specific to patients developing headaches may be evaluated by imaging.Goto M, Shibata Y, Ishiyama S, Matsumaru Y, Ishikawa E. Brain microstructure and brain function changes in space headache by head-down-tilted bed rest. Aerosp Med Hum Perform. 2023; 94(9):678-685.

The Modifying of Functional Connectivity Induced by Peripheral Nerve Field Stimulation using Electroacupuncture for Migraine: A Prospective Clinical Study.

OBJECTIVE: We examined the functional connectivity (FC) in patients with migraine compared with healthy subjects before and after C2 peripheral nerve field stimulation with electroacupuncture (EA-C2-PNfS) to evaluate the effect of EA-C2-PNfS and elucidate the mechanism of migraine. METHODS: Twenty-six patients with migraine and 24 healthy controls were recruited. All patients underwent resting state functional magnetic resonance imaging before and after 3 months of EA-C2-PNfS. We evaluated a numerical rating scale, the Headache Impact Test, and the Self-Rating Depression Scale, which assesses depression. Healthy controls underwent magnetic resonance imaging twice at a 3-month interval without acupuncture. An analysis of FC in the region of interest in the pain matrix was performed. RESULTS: Twenty patients with migraine and 23 healthy controls (mean ± standard deviation: 44.9 ± 12.9 years of age) were included. Three patients had migraine with aura (55.0 ± 18.0 years of age), 11 patients had migraine without aura (MWoA) (45.6 ± 14.6 years of age), and six patients had chronic migraine (40.8 ± 13.9 years of age). The clinical assessments significantly improved after EA-C2-PNfS in the MWoA group only. In FC analysis, the MWoA group showed a significant decrease after EA-C2-PNfS in FC between the right hypothalamus and left insula. Right hypothalamus-related FC was lower before acupuncture in the chronic migraine group than in the MWoA group. CONCLUSION: After EA-C2-PNfS for MWoA, significant changes in FC were observed at the hypothalamus and insula. Our results indicate that EA-C2-PNfS could improve migraine headache by modifying pain-related FC.

White matter diffusion abnormalities in migraine and medication overuse headache: A 1.5-T tract-based spatial statistics study.

OBJECTIVES: Migraine and medication overuse headache are common, but its pathophysiology remains unclear. Differential diagnosis of chronic headache is still challenging. Conventional brain imaging techniques exclude secondary causes of headache but cannot produce a proper diagnosis. Accordingly, more sensitive diagnostic methods are needed for certain diagnosis. In the present study, we performed voxel-wise tract-based spatial statistics of 1.5-T diffusion tensor imaging in migraine patients and healthy volunteers. PATIENTS AND METHODS: One hundred and three migraine patents and 46 healthy volunteers were registered. The fractional anisotropy values in the white matter of each group compared to age-matched healthy volunteers. RESULTS: Compared to the controls, the migraine without aura with medication overuse headache had remarkable fractional anisotropy decrease in the white matter in several regions. The migraine with aura without medication overuse headache also had significant fractional anisotropy decrease compared to the controls. The disease duration and frequency of migraine attack were not correlated with fractional anisotropy values of the corpus callosum. CONCLUSION: Our 1.5-T DTI study demonstrated significantly lower fractional anisotropy in the white matter in the MoA with medication overuse headache and MwA without medication overuse headache groups, suggesting that fractional anisotropy abnormalities may be useful biomarkers in headache patients.

Clinical Effect of C2 Peripheral Nerve Field Stimulation Using Electroacupuncture for Primary Headache.

OBJECTIVE: We applied C2 peripheral nerve field stimulation using electroacupuncture (EA-C2-PNfS) for primary headache, and investigated its clinical effectiveness. MATERIALS AND METHODS: Fifty-four primary headache patients (10 men, 44 women) with a mean age of 48.6 ± 15.0 years underwent EA-C2-PNfS for three months. We used questionnaires to assess outcomes; pain intensity (11-point numerical rating scale [NRS]), quality of daily life (Headache Impact Test [HIT-6]), depression (Self-Rating Depression Scale [SDS]). Monthly headache days and acute headache medication days were obtained from diaries. RESULTS: The headache intensity significantly declined after the EA-C2-PNfS with reduction of NRS pain scale; 7.4 ± 1.9 at baseline, 4.9 ± 2.9 at three month (p < 0.001). Both HIT-6 and SDS showed significant improvement (p < 0.001). Some patients showed moderate depression in SDS before treatment, that was alleviated in patients with tension-type headache after the EA-C2-PNfS. Monthly headache days significantly decreased from 18.0 ± 9.0 at one month to 14.0 ± 10.2 at three months (p < 0.001), accompanied with reduction of the monthly acute headache medication days from 8.0 ± 6.7 to 6.4 ± 6.5 (p = 0.003). CONCLUSIONS: EA-C2-PNfS was successfully used for reducing severity and disability in primary headache patients. We conclude that EA-C2-PNfS is a favorable option for medically intractable primary headache as less-invasive neuromodulation.