title: Does visual cortex lactate increase following photic stimulation in migraine without aura patients? A functional (1)H-MRS study.
abstract: Proton magnetic resonance spectroscopy ((1)H-MRS) has been used in a number of studies to assess noninvasively the temporal changes of lactate (Lac) in the activated human brain. Migraine neurobiology involves lack of cortical habituation to repetitive stimuli and a mitochondrial component has been put forward. Our group has recently demonstrated a reduction in the high-energy phosphates adenosine triphosphate (ATP) and phosphocreatine (PCr) in the occipital lobe of migraine without aura (MwoA) patients, at least in a subgroup, in a phosphorus MRS ((31)P-MRS) study. In previous studies, basal Lac levels or photic stimulation (PS)-induced Lac levels were found to be increased in patients with migraine with aura (MwA) and migraine patients with visual symptoms and paraesthesia, paresia and/or dysphasia, respectively. The aim of this study was to perform functional (1)H-MRS at 3 T in 20 MwoA patients and 20 control subjects. Repetitive visual stimulation was applied using MR-compatible goggles with 8 Hz checkerboard stimulation during 12 min. We did not observe any significant differences in signal integrals, ratios and absolute metabolite concentrations, including Lac, between MwoA patients and controls before PS. Lac also did not increase significantly during and following PS, both for MwoA patients and controls. Subtle Lac changes, smaller than the sensitivity threshold (i.e. estimated at 0.1-0.2 μmol/g at 3 T), cannot be detected by MRS. Our study does, however, argue against a significant switch to non-aerobic glucose metabolism during long-lasting PS of the visual cortex in MwoA patients.
authors.affiliation: Department of Radiology and Nuclear Medicine, MR-department (-1K12B), Ghent University Hospital, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium. harmen.reyngoudt@ugent.be
authors.forename: Harmen
authors.initials: H
authors.lastname: Reyngoudt
authors.forename: Koen
authors.initials: K
authors.lastname: Paemeleire
authors.forename: Anneloor
authors.initials: A
authors.lastname: Dierickx
authors.forename: Benedicte
authors.initials: B
authors.lastname: Descamps
authors.forename: Pieter
authors.initials: P
authors.lastname: Vandemaele
authors.forename: Yves
authors.initials: Y
authors.lastname: De Deene
authors.forename: Eric
authors.initials: E
authors.lastname: Achten
mesh_terms: D000328:Adult; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001786:Blood Glucose / Q000378:metabolism; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D006801:Humans; D019344:Lactic Acid / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D020326:Migraine without Aura / Q000378:metabolism* / Q000503:physiopathology; D008954:Models, Biological; D010775:Photic Stimulation; D011522:Protons; D014793:Visual Cortex / Q000378:metabolism* / Q000503:physiopathology; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D011522:Protons; D001224:Aspartic Acid; D019344:Lactic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline