Serial susceptibility weighted MRI measures brain iron and microbleeds in dementia.
A new iron sensitive MR sequence (susceptibility weighted imaging - SWI) enabling the simultaneous quantitation of regional brain iron levels and brain microbleeds (BMB) has been acquired serially to study dementia. Cohorts of mildly cognitively impaired (MCI) elderly (n = 73) and cognitively normal participants (n = 33) have been serially evaluated for up to 50 months. SWI phase values (putative iron levels) in 14 brain regions were measured and the number of BMB were counted for each SWI study. SWI phase values showed a left putaminal mean increase of iron (decrease of phase values) over the study duration in 27 participants who progressed to dementia compared to Normals (p = 0.035) and stable MCI (p = 0.01). BMB were detected in 9 out of 26 (38%) MCI participants who progressed to dementia and are a significant risk factor for cognitive failure in MCI participants [risk ratio = 2.06 (95% confidence interval 1.37-3.12)]. SWI is useful to measure regional iron changes and presence of BMB, both of which may be important MR-based biomarkers for neurodegenerative diseases.
Neurosurgery Center for Research, Training, and Education, Loma Linda University, 11175 Campus Street, Suite 11113, Loma Linda, CA 92350, USA. wkirsch@llu.edu
Wolff
W
Kirsch
Grant
G
McAuley
Barbara
B
Holshouser
Floyd
F
Petersen
Muhammad
M
Ayaz
Harry V
HV
Vinters
Cindy
C
Dickson
E Mark
EM
Haacke
William
W
Britt
James
J
Larseng
Ivan
I
Kim
Claudius
C
Mueller
Matthew
M
Schrag
Daniel
D
Kido
D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000378:metabolism* / Q000473:pathology; D001931:Brain Mapping; D003072:Cognition Disorders / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D003704:Dementia / Q000150:complications / Q000473:pathology*; D004198:Disease Susceptibility / Q000175:diagnosis*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D020300:Intracranial Hemorrhages / Q000150:complications / Q000473:pathology*; D018810:Magnetic Resonance Angiography / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests