Sodium MR imaging detection of mild Alzheimer disease: preliminary study.
OBJECTIVE
There is significant interest in the development of novel noninvasive techniques for the diagnosis of Alzheimer disease (AD) and tracking its progression. Because MR imaging has detected alterations in sodium levels that correlate with cell death in stroke, we hypothesized that there would be alterations of sodium levels in the brains of patients with AD, related to AD cell death.


METHODS
A total of 10 volunteers (5 with mild AD and 5 healthy control subjects) were scanned with a 20-minute sodium (23Na) MR imaging protocol on a 3T clinical scanner.


RESULTS
After normalizing the signal intensity from the medial temporal lobes corresponding to the hippocampus with the ventricular signal intensity, we were able to detect a 7.5% signal intensity increase in the brains of patients with AD (AD group, 68.25% +/- 3.4% vs control group, 60.75% +/- 2.9%; P < .01). This signal intensity enhancement inversely correlated with hippocampal volume (AD group, 3.22 +/- 0.50 cm3 vs control group, 3.91 +/- 0.45 cm3; r2 = 0.50).


CONCLUSIONS
This finding suggests that sodium imaging may be a clinically useful tool to detect the neuropathologic changes associated with AD.
Mellon
E A
EA
Department of Radiology, MMRRCC, University of Pennsylvania, Philadelphia, PA, USA. eric@mail.mmrrcc.upenn.edu
Pilkinton
D T
DT
Clark
C M
CM
Elliott
M A
MA
Witschey
W R
WR
Borthakur
A
A
Reddy
R
R
D000368:Aged; D000544:Alzheimer Disease / Q000378:metabolism* / Q000473:pathology*; D015415:Biomarkers / Q000032:analysis; D001921:Brain / Q000378:metabolism* / Q000473:pathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D012964:Sodium / Q000032:analysis*; D014018:Tissue Distribution
D015415:Biomarkers; D012964:Sodium