Impact of protein content on proton diffusibility in intracranial cysts.
OBJECTIVE
The physical background of diffusion phenomena in intracranial cysts is unclear in some cases. To evaluate a potential dependency of proton diffusion on the concentration of proteins in cystic lesions we investigated the correlation of diffusion weighted imaging (DWI) and magnetization transfer ratio imaging (MTR) in intracranial cystic pathologies in vivo and in vitro with protein solutions.


METHODS
21 patients (14 male/7 female) with intracranial cystic lesions underwent preoperative MRI (1.5T) including MTR and DWI sequences. For comparison a series of samples with declining concentration of albumin was investigated in vitro with a 7T animal scanner.


RESULTS
In the patients examination mean ADC values were 1.93×10-3mm2/sec and mean MTR values were 0.2. Mean ADC value of the albumin solutions was 0.22× 0-3mm2/sec and mean MTR was 0.12. ADC and MTR values showed a strong negative correlation in the patients (Spearman's rank correlation rs=-0.80, p<0.01) and a very strong negative correlation in the in vitro examinations (rs=-1.0, p<0.01).


CONCLUSIONS
The strong negative correlation of ADC and MTR values suggest a strong influence of proteins on proton diffusion in intracranial cysts. The phenomena can be explained by macromolecules that bind nearby protons in their vicinity.
Neuroradiology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, Hamburg, Germany. e.goebell@uke.de
E
E
Goebell
J
J
Fiehler
T
T
Martens
C
C
Hagel
N D
ND
Forkert
A
A
Russjan
M
M
Rosenkranz
J-H
JH
Buhk
M
M
Groth
J
J
Sedlacik
D000328:Adult; D000368:Aged; D016080:Arachnoid Cysts; D016477:Artifacts; D001927:Brain Diseases / Q000378:metabolism* / Q000473:pathology*; D003560:Cysts / Q000737:chemistry* / Q000473:pathology*; D004058:Diffusion; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000737:chemistry*; D011522:Protons; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult
D009419:Nerve Tissue Proteins; D011522:Protons