Elisabetta Pagani1, Maria Assunta Rocca1,2, Roberta Messina1, Bruno Colombo2, Giancarlo Comi2, Andrea Falini3, and Massimo Filippi1,2
1Neuroimaging Research Unit, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy, 2Department of Neurology, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy, 3Department of Neuroradiology, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
Synopsis
Aim of the study was to
explore longitudinal gray matter (GM)
changes over a four-year follow up in migraine patients and their
association with patients’ clinical characteristics and disease
activity. Brain dual-echo and 3D T1-weighted scans were acquired from
25 patients with migraine and 25 healthy controls at baseline
and after 4 years. At follow up, compared to
controls, migraine patients had an increased volume of
fronto-parietal regions, whereas they developed atrophy of the right
thalamus and occipital areas. The migraine brain changes dynamically
over time. Various pathophysiological
mechanism might affect different brain
regions in migraineurs after 4 years.Background
Previous
studies have shown diffuse gray matter (GM) abnormalities in regions
involved in pain and visual processing in migraine patients. A
longitudinal study found GM atrophy
of sensory-discriminative brain regions in these patients after one
year.
Purpose
To explore longitudinal
GM changes over a four-year follow up in
migraine patients and their association with patients’ clinical
characteristics and disease activity.
Methods
Using
a 3.0 Tesla scanner, brain dual-echo and 3D T1-weighted scans were
acquired from 25 patients with migraine and 25 healthy controls at
baseline and after 4 years (range of follow-up years: controls
1.7-6.6, patients: 2.9-5.6 years). Tensor-based morphometry (1) and
SPM12 were used to assess longitudinal changes of
GM volumes in migraine patients after 4 years and according to the
disease duration and attack frequency and their changes.
Pairwise longitudinal registration (2) was used to align the
first and second scan of each subject: the method is based on
pairwise inverse-consistent registration and incorporates a bias
field correction. The rate of volume change was quantified by saving
the map of divergence of the velocity field, where positive values
indicate expansion and negative values contraction. The mid-point
average template image was also saved and used for groupwise
alignment (3) to the final customized template
and then to the standard space (MNI
atlas).
Results
Eight patients (32%) reported an increased number of migraine attacks
at follow up. At baseline, compared to controls,
migraine patients showed cerebellar GM atrophy and higher volume of
regions of the right fronto-temporo-parietal lobes. At follow up,
compared to controls, migraine patients had an increased volume of
fronto-parietal regions (Figure 1), which was related to a higher
number of migraine attacks at baseline (r=0.58, p<0.001) and was
more prominent in those patients with increasing number of attacks
during the study. At follow up, compared to controls, migraine
patients developed GM atrophy of the right thalamus and occipital
areas (Figure 2). Thalamic atrophy was more pronounced in patients
with a longer disease duration.
Conclusions
The migraine brain changes dynamically over time.
Various pathophysiological mechanisms
might affect different brain regions in migraineurs after 4 years. GM
volume increase of fronto-parietal areas involved in nociception
might represent a compensatory response to high migraine attack
frequency. GM atrophy of the thalamus, which plays a fundamental role
in migraine pathophysiology, might be influenced by disease
progression.
Acknowledgements
No acknowledgement found.References
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