An in vitro and in vivo analysis of the correlation between susceptibility-weighted imaging phase values and R2* in cirrhotic livers.

Abstract

OBJECTIVE:

To establish a baseline of susceptibility-weighted imaging (SWI) phase value as a means of detecting iron abnormalities in cirrhotic liver and to analyze its relationship with R2*.

MATERIALS AND METHODS:

Sixteen MnCl(2) phantoms, thirty-seven healthy individuals and 87 cirrhotic patients were performed SWI and multi-echo T2*-weighted imaging, and the signal processing in NMR (SPIN) software was used to measure the radian on SWI phase images and the R2* on T2* maps. The mean minus two times standard deviation (SD) of Siemens Phase Unit (SPU) in healthy individuals was designated as a threshold to separate the regions of interest (ROIs) into high- and low-iron areas in healthy participants and cirrhotic patients. The SWI phase values of high-iron areas were calculated. The R2* values was measured in the same ROI in both healthy participants and patients.

RESULTS:

SWI phase values correlated linearly with R2* values in cases of MnCl(2) concentrations lower than 2.3 mM in vitro (r = -0.996, P<0.001). The mean value and SD of 37 healthy participants were 2003 and 15 (SPU), respectively. A threshold of 1973 SPU (-0.115 radians) was determined. The SWI phase value and R2* values had a negative correlation in the cirrhotic patients (r = -0.742, P<0.001). However, no similar relationship was found in the healthy individuals (r = 0.096, P = 0.576). Both SWI phase values and R2* values were found to have significant correlations with serum ferritin concentrations in 42 patients with blood samples (r = -0.512, P = 0.001 and r = 0.641, P<0.001, respectively).

CONCLUSION:

SWI phase values had significant correlations with R2* after the establishment of a baseline on the phase image. SWI phase images may be used for non-invasive quantitative measurement of mild and moderate iron deposition in hepatic cirrhosis in vivo.

• Authors: Ran Tao, Jiuquan Zhang, Yongming Dai, Zhonglan You, Yi Fan, Jinguo Cui, Jian Wang
• Journal: PloS one (PLoS One) Vol. 7 Issue 9 Pg. e45477 ( 2012) ISSN: 1932-6203 [Electronic] United States
• PMID: 23029037 (Publication Type: Journal Article)

Chemical References

• Ferritins
• Iron

Topics

• Adult
• Case-Control Studies
• Female
• Ferritins (blood)
• Humans
• Iron (metabolism)
• Liver (metabolism, pathology)
• Liver Cirrhosis (diagnosis, metabolism, pathology)
• Magnetic Resonance Imaging (instrumentation, methods)
• Male
• Middle Aged
• Phantoms, Imaging
• Young Adult