Correlation between intravoxel incoherent motion (IVIM) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters in rectal cancer
Yanyan Xu1, Hongliang Sun1, Kaining Shi2, and Wu Wang1

1Radiology, China-Japan Friendship hospital, Beijing, China, People's Republic of, 2Philips Healthcare China, Beijing, China, People's Republic of

Synopsis

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has been applied in rectal cancer for the purpose of characterizing tumor perfusion[1]. However, DCE-MRI should use intravenous contrast media based gadolinium, which will increase the risk of kidney systemic fibrosis[2]. The bi-exponential analysis in intravoxel incoherent motion (IVIM) model can separate microscopic circulation perfusion with pure water diffusion[3-4]. Correlation has been derived between the IVIM perfusion parameters f and D* and the classical perfusion parameters[5-6]. However, its relationship with DCE-MRI parameters in rectal cancer has not been clarified.

Purpose

To determine the correlation between intravoxel incoherent motion (IVIM) and multiphase dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters in patients with rectal cancer.

Methods

Twenty-one patients with histological diagnosis of rectal cancer were included in this study. All pelvis magnetic resonance imaging were performed in a 3.0T MR unit (Philips 3.0T Ingenia, Philips Medical System, The Netherlands) including diffusion-weighted imaging using eight b values (0, 25, 50, 75, 150, 400, 800 and 1000s/mm2) and DCE-MRI (40 dynamic phases). IVIM perfusion-related parameters (f, perfusion fraction; D*, pseudo-diffusion coefficient; f·D*, the multiplication of the two parameters) were calculated by bi-exponential analysis. Semi-quantitative DCE-MRI parameters including relative enhancement (RE), maximum enhancement (ME), maximum relative enhancement (MRE), time to peak (TTP), wash in rate (WIR) were automatically calculated after region of interest (ROI) being selected along the outline of tumor maximal dimension, meanwhile relevant signal intensity (SI) time curves were obtained. Correlations between f and all semi-quantitative DCE-MRI parameters were respectively analyzed using Pearson’s correlation coefficients, D* and f·D* were also similarly analyzed. Interobserver agreements were evaluated using the intraclass correlation coefficient (ICC) and Bland-Altman analysis. P<0.05 was considered to indicate a statistically significant difference.

Results

There were 16 males and 5 females with a median age of 61.7 years (range, 38-76 years). Interobserver reproducibility were good (ICC=0.8537-0.9754; narrow with of 95% limits of agreement). There were significant correlation between D*and TTP (r= -0.468; p=0.033), f·D*and TTP (r= -0.474; p=0.030), no correlation was observed between f and other DCE-MRI parameters. Conclusion: IVIM perfusion-related parameters demonstrated moderate correlations with DCE-MRI semi-quantitative parameters in rectal cancer.

Conclusion

IVIM perfusion-related parameters demonstrated moderate correlations with DCE-MRI semi-quantitative parameters in rectal cancer.

Acknowledgements

This work was supported by a grant from the National Natural Science Foundation of China (No. 81501469).

References

1. Intven M, Reerink O, Philippens ME. Dynamic contrast enhanced MR imaging for rectal cancer response assessment after neo-adjuvant chemoradiation. J Magn Reson Imaging. 2015 Jun;41(6):1646-53.

2. Padhani AR. Dynamic contrast-enhanced MRI in clinical oncology: current status and future directions. J Magn Reson Imaging. 2002; 16(4): 407-22.

3. Le Bihan D, Breton E, Lallemand D, et al. Separation of diffusion and perfusion in intravoxel incoherent motion MR imaging. Radiology. 1988;168(2):497-505.

4. Koh DM, Collins DJ, Orton MR. Intravoxel incoherent motion in body diffusion-weighted MRI: reality and challenges. Am J Roentgenol. 2011 Jun;196(6):1351-61.

5. Le Bihan D, Turner R. The capillary network: a link between IVIM and classical perfusion. Magn Reson Med. 1992; 27(1):171–178.

6. Fujima N, Yoshida D, Sakashita T, et al. Intravoxel incoherent motion diffusion-weighted imaging in head and neck squamous cell carcinoma: assessment of perfusion-related parameters compared to dynamic contrast-enhanced MRI. Magn Reson Imaging. 2014; 32(10):1206-13.

Figures

Figure 1. Scatterplots of DCE-MRI perfusion parameters compared with IVIM perfusion-related parameters. Left: moderate negative correlation between D*(×10-3mm2/s) and TTP (s) (r= -0.468; p=0.033). Right: moderate negative correlation between fD*(×10-3mm2/s) and TTP (s) (r= -0.474; p=0.030).

Figure 2. A series of images for a 61-year-old men with mid-lower rectal cancer (first line: [from left to right] T1-weighted image, T2-weighted image, contrast-enhanced T1-weighted mask image; second line: [from left to right] contrast-enhanced T1-weighted image, Diffusion weighted image and bi-exponential fit of the diffusion signal decay over a wide-range of b values (range 0- 1000s/mm2 ).



Proc. Intl. Soc. Mag. Reson. Med. 24 (2016)
2971