Occipital proton magnetic resonance spectroscopy (1H-MRS) reveals normal metabolite concentrations in retinal visual field defects.
BACKGROUND
Progressive visual field defects, such as age-related macular degeneration and glaucoma, prevent normal stimulation of visual cortex. We investigated whether in the case of visual field defects, concentrations of metabolites such as N-acetylaspartate (NAA), a marker for degenerative processes, are reduced in the occipital brain region.


RESULTS
Participants known with glaucoma, age-related macular degeneration (the two leading causes of visual impairment in the developed world), and controls were examined by proton MR spectroscopic ((1)H-MRS) imaging. Absolute NAA, Creatine and Choline concentrations were derived from a single-voxel in the occipital region of each brain hemisphere. No significant differences in metabolites concentrations were found between the three groups.


CONCLUSIONS
We conclude that progressive retinal visual field defects do not affect metabolite concentration in visual brain areas suggesting that there is no ongoing occipital degeneration. We discuss the possibility that metabolite change is too slow to be detectable.
Boucard
Christine C
CC
CBCN Neuro-imaging Center, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands. joyce@brain.riken.jp
Hoogduin
Johannes M
JM
van der Grond
Jeroen
J
Cornelissen
Frans W
FW
D000368:Aged; D000369:Aged, 80 and over; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000032:analysis; D015415:Biomarkers; D002794:Choline / Q000032:analysis*; D003401:Creatine / Q000032:analysis*; D005260:Female; D005901:Glaucoma / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D008268:Macular Degeneration / Q000378:metabolism* / Q000473:pathology; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009410:Nerve Degeneration; D009778:Occipital Lobe / Q000737:chemistry* / Q000473:pathology; D011522:Protons; D012607:Scotoma / Q000378:metabolism / Q000473:pathology; D014794:Visual Fields
D015415:Biomarkers; D011522:Protons; D001224:Aspartic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline