Characterizing iron deposition in multiple sclerosis lesions using susceptibility weighted imaging.
OBJECTIVE
To investigate whether the variable forms of putative iron deposition seen with susceptibility weighted imaging (SWI) will lead to a set of multiple sclerosis (MS) lesion characteristics different than that seen in conventional MR imaging.


METHODS
Twenty-seven clinically definite MS patients underwent brain scans using magnetic resonance imaging including: pre- and postcontrast T1-weighted imaging, T2-weighted imaging, FLAIR, and SWI at 1.5 T, 3 T, and 4 T. MS lesions were identified separately in each imaging sequence. Lesions identified in SWI were reevaluated for their iron content using the SWI filtered phase images.


RESULTS
There were a variety of new lesion characteristics identified by SWI, and these were classified into six types. A total of 75 lesions were seen only with conventional imaging, 143 only with SWI, and 204 by both. From the iron quantification measurements, a moderate linear correlation between signal intensity and iron content (phase) was established.


CONCLUSIONS
The amount of iron deposition in the brain may serve as a surrogate biomarker for different MS lesion characteristics. SWI showed many lesions missed by conventional methods and six different lesion characteristics. SWI was particularly effective at recognizing the presence of iron in MS lesions and in the basal ganglia and pulvinar thalamus.
Haacke
E Mark
EM
Department of Radiology, Wayne State University, Detroit, Michigan 48201, USA. nmrimaging@aol.com
Makki
Malek
M
Ge
Yulin
Y
Maheshwari
Megha
M
Sehgal
Vivek
V
Hu
Jiani
J
Selvan
Madeswaran
M
Wu
Zhen
Z
Latif
Zahid
Z
Xuan
Yang
Y
Khan
Omar
O
Garbern
James
J
Grossman
Robert I
RI
D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D001921:Brain / Q000378:metabolism* / Q000473:pathology*; D001931:Brain Mapping / Q000379:methods; D003287:Contrast Media; D017352:Echo-Planar Imaging / Q000379:methods; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D007501:Iron / Q000378:metabolism*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis / Q000378:metabolism* / Q000473:pathology*; D055815:Young Adult
D015415:Biomarkers; D003287:Contrast Media; D007501:Iron