臺灣博碩士論文加值系統

目的:

探討因脂肪飽和技術的施用與否，所造成腮腺動態對比增強微灌流磁振造影參數差異之成因。

方法:

本研究實驗分為三部分: 一、分析兩組臨床病患(脂肪飽和技術與非脂肪飽和技術各18人)腮腺的動態對比增強微灌流磁振造影參數；二、製作三組不同脂肪比例的假體，每組各分為六種對比劑濃度，各用脂肪飽和技術與非脂肪飽和技術擷取影像分析；三、招募九名健康受試者，各接受兩種不同微灌流造影掃描。

將使用脂肪飽和技術及非脂肪飽和技術兩種方法的微灌流參數利用T檢定比較兩組之間差異，並利用線性迴歸觀察脂肪含量與參數之間的關係，統計結果最後用Bonferroni修正多重比較。

結果:

病患資料統計分析顯示，非使用脂肪飽和技術的病人，A(5.08±2.95 a.u.)、PE (34.44±12.48%)以及斜率(1.08±0.60%/s)三個參數，顯著低於使用脂肪飽和技術的病人(8.90±4.03 a.u., 74.55±13.79%, 以及1.79±0.85%/s)。仿體實驗結果顯示信號增強的比例正比於對比劑的濃度，並且非使用脂肪飽和技術的影像信號增強比例顯著低於使用脂肪飽和技術。受試者也是在非使用脂肪飽和技術的參數顯著的低於使用脂肪飽和技術。脂肪飽和技術造成的參數顯著差異，則可以利用圈選脂肪含量較少的組織，做為標準化的基準強度來降低差異。

結論:
富含脂肪的組織如腮腺，動態對比增強微灌流磁振造影特徵會受到脂肪含量影響，使用脂肪飽和技術的可以降低脂肪含量對於參數的影響。選擇脂肪含量較少的組織，做為標準化的基準強度也可以降低影響。

Purpose:
To investigate the discrepancy of perfusion parameters of the parotid gland acquired by fat-saturated (FS) versus non-fat-saturated (NFS) dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

Materials and Methods:
Approved by a local institutional review board with written informed consent obtained, this study consisted of three parts. First, a retrospective study analyzed DCE-MRI data previously acquired using NFS (18 patients) or FS scans (18 patients). Second, a phantom study simulated the signal enhancements in the presence of Gd contrast agent at 6 different concentrations and 3 different fat contents. Finally, a prospective study recruited 9 healthy volunteers to investigate the influence of fat suppression on perfusion quantification on the same subjects. T tests and linear regression analysis were used for statistical analysis with Bonferroni correction applied for multiple comparisons.

Results:
Patients undergoing NFS DCE-MR scan showed significantly lower parameter A (5.08±2.95 a.u.), peak enhancement (PE) (34.44±12.48%), and slope (1.08±0.60%/s) as compared to 8.90±4.03 a.u., 74.55±13.79%, and 1.79±0.85%/s, respectively, in those with FS scan (all P<0.0167). Phantom study showed that the relative signal enhancement was proportional to the dose of gadolinium contrast agent and was higher in FS scan than in NFS scan. Volunteer study showed significantly lower parameter A (6.75±2.38 a.u.), PE (42.12±14.87%), and slope (1.43±0.54%/s) in NFS scan as compared to 17.63±8.56 a.u., 104.22±25.15%, and 3.68±1.67%/s, respectively, in those with FS scan (all P<0.005). These perfusion parameter differences were remedied by using skeletal muscles and pure water as reference on in vivo and phantom studies, respectively.

Conclusion:
DCE-MRI perfusion characterization is affected by the use of FS on fat-containing tissues such as parotid glands. The use of fat saturation is important to reduce the influence of parotid fat content on perfusion quantification. The selection of a relatively fat-free tissue as baseline is a simple and effective method to reduce bias from fat content in DCE MRI of the parotid glands.

口試委員審定書 i
論文誌謝 ii
中文摘要 iii
Abstract iv
Contents vi
Table of figures and table vii
Chapter 1 : Introduction 1
Chapter 2 : Dynamic contrast-enhanced MRI 4
Contrast Agent 4
Nephrogenic systemic fibrosis 5
DCE-MRI and Brix Model 6
Chapter 3 : Materials and Methods 8
Retrospective patient study 9
Phantom study 10
Prospective volunteer study 11
Image Processing and Data Analysis 14
Statistical analysis 19
Chapter 4 : Results 20
Chapter 5 : Discussion and Conclusion 30
Chapter 6 : References 40

1.Yabuuchi, H., et al., Salivary gland tumors: diagnostic value of gadolinium-enhanced dynamic MR imaging with histopathologic correlation. Radiology, 2003. 226(2): p. 345-54.
2.Ikeda, M., et al., Warthin tumor of the parotid gland: diagnostic value of MR imaging with histopathologic correlation. AJNR Am J Neuroradiol, 2004. 25(7): p. 1256-62.
3.Alibek, S., et al., The value of dynamic MRI studies in parotid tumors. Acad Radiol, 2007. 14(6): p. 701-10.
4.Yabuuchi, H., et al., Parotid gland tumors: can addition of diffusion-weighted MR imaging to dynamic contrast-enhanced MR imaging improve diagnostic accuracy in characterization? Radiology, 2008. 249(3): p. 909-16.
5.Hisatomi, M., et al., Diagnostic value of dynamic contrast-enhanced MRI in the salivary gland tumors. Oral Oncol, 2007. 43(9): p. 940-7.
6.Lam, P.D., et al., Differentiating benign and malignant salivary gland tumors: diagnostic criteria and the accuracy of dynamic contrast-enhanced MRI with high temporal resolution. Br J Radiol, 2015: p. 20140685.
7.Juan, C.J., et al., Perfusion characteristics of late radiation injury of parotid glands: quantitative evaluation with dynamic contrast-enhanced MRI. Eur Radiol, 2009. 19(1): p. 94-102.
8.Cheng, C.C., et al., Parotid perfusion in nasopharyngeal carcinoma patients in early-to-intermediate stage after low-dose intensity-modulated radiotherapy: evaluated by fat-saturated dynamic contrast-enhanced magnetic resonance imaging. Magn Reson Imaging, 2013. 31(8): p. 1278-84.
9.Roberts, C., et al., Glandular function in Sjogren syndrome: assessment with dynamic contrast-enhanced MR imaging and tracer kinetic modeling--initial experience. Radiology, 2008. 246(3): p. 845-53.
10.Lee, F.K., et al., Radiation injury of the parotid glands during treatment for head and neck cancer: assessment using dynamic contrast-enhanced MR imaging. Radiat Res, 2011. 175(3): p. 291-6.
11.Houweling, A.C., et al., MRI to quantify early radiation-induced changes in the salivary glands. Radiother Oncol, 2011. 100(3): p. 386-9.
12.Iguchi, H., et al., Epithelioid myoepithelioma of the accessory parotid gland: pathological and magnetic resonance imaging findings. Case Rep Oncol, 2014. 7(2): p. 310-5.
13.Sumi, M., et al., Salivary gland tumors: use of intravoxel incoherent motion MR imaging for assessment of diffusion and perfusion for the differentiation of benign from malignant tumors. Radiology, 2012. 263(3): p. 770-7.
14.Espinoza, S., et al., Warthin''s tumor of parotid gland: Surgery or follow-up? Diagnostic value of a decisional algorithm with functional MRI. Diagn Interv Imaging, 2014.
15.Kato, H., et al., Perfusion imaging of parotid gland tumours: usefulness of arterial spin labeling for differentiating Warthin''s tumours. Eur Radiol, 2015.
16.Horikoshi, T., et al., Head and neck MRI of Kimura disease. Br J Radiol, 2011. 84(1005): p. 800-4.
17.Zhang, L., et al., Functional evaluation with intravoxel incoherent motion echo-planar MRI in irradiated salivary glands: a correlative study with salivary gland scintigraphy. J Magn Reson Imaging, 2001. 14(3): p. 223-9.
18.Marzi, S., et al., Early radiation-induced changes evaluated by intravoxel incoherent motion in the major salivary glands. J Magn Reson Imaging, 2015. 41(4): p. 974-82.
19.Schwenzer, N.F., et al., MR measurement of blood flow in the parotid gland without contrast medium: a functional study before and after gustatory stimulation. NMR Biomed, 2008. 21(6): p. 598-605.
20.Chang, H.C., et al., Effects of gender, age, and body mass index on fat contents and apparent diffusion coefficients in healthy parotid glands: an MRI evaluation. Eur Radiol, 2014. 24(9): p. 2069-76.
21.Dutta, S.K., et al., Functional and structural changes in parotid glands of alcoholic cirrhotic patients. Gastroenterology, 1989. 96(2 Pt 1): p. 510-8.
22.Izumi, M., et al., Premature fat deposition in the salivary glands associated with Sjogren syndrome: MR and CT evidence. AJNR Am J Neuroradiol, 1997. 18(5): p. 951-8.
23.Tartaglino, L.M., V.M. Rao, and D.A. Markiewicz, Imaging of radiation changes in the head and neck. Semin Roentgenol, 1994. 29(1): p. 81-91.
24.Tofts, P.S., Modeling tracer kinetics in dynamic Gd-DTPA MR imaging. J Magn Reson Imaging, 1997. 7(1): p. 91-101.
25.Donahue, K.M., et al., Studies of Gd-DTPA relaxivity and proton exchange rates in tissue. Magn Reson Med, 1994. 32(1): p. 66-76.
26.Tofts, P.S. and A.G. Kermode, Measurement of the blood-brain barrier permeability and leakage space using dynamic MR imaging. 1. Fundamental concepts. Magn Reson Med, 1991. 17(2): p. 357-67.
27.Grobner, T., Gadolinium--a specific trigger for the development of nephrogenic fibrosing dermopathy and nephrogenic systemic fibrosis? Nephrol Dial Transplant, 2006. 21(4): p. 1104-8.
28.Marckmann, P., et al., Clinical manifestation of gadodiamide-related nephrogenic systemic fibrosis. Clin Nephrol, 2008. 69(3): p. 161-8.
29.Mendichovszky, I.A., et al., Gadolinium and nephrogenic systemic fibrosis: time to tighten practice. Pediatr Radiol, 2008. 38(5): p. 489-96; quiz 602-3.
30.Gilliet, M., et al., Successful treatment of three cases of nephrogenic fibrosing dermopathy with extracorporeal photopheresis. Br J Dermatol, 2005. 152(3): p. 531-6.
31.Brix, G., et al., Pharmacokinetic parameters in CNS Gd-DTPA enhanced MR imaging. J Comput Assist Tomogr, 1991. 15(4): p. 621-8.
32.Wood, M.L. and P.A. Hardy, Proton relaxation enhancement. J Magn Reson Imaging, 1993. 3(1): p. 149-56.
33.Griffith, J.F., et al., Vertebral bone mineral density, marrow perfusion, and fat content in healthy men and men with osteoporosis: dynamic contrast-enhanced MR imaging and MR spectroscopy. Radiology, 2005. 236(3): p. 945-51.
34.Ma, H.T., et al., Modified brix model analysis of bone perfusion in subjects of varying bone mineral density. J Magn Reson Imaging, 2010. 31(5): p. 1169-75.
35.Tofts, P.S., B. Berkowitz, and M.D. Schnall, Quantitative analysis of dynamic Gd-DTPA enhancement in breast tumors using a permeability model. Magn Reson Med, 1995. 33(4): p. 564-8.
36.Tofts, P.S., et al., Estimating kinetic parameters from dynamic contrast-enhanced T(1)-weighted MRI of a diffusable tracer: standardized quantities and symbols. J Magn Reson Imaging, 1999. 10(3): p. 223-32.
37.Schmidt, M.A., et al., Breast dynamic contrast-enhanced examinations with fat suppression: are contrast-agent uptake curves affected by magnetic field inhomogeneity? Eur Radiol, 2013. 23(6): p. 1537-45.
38.Juan, C.J., et al., Salivary glands: echo-planar versus PROPELLER Diffusion-weighted MR imaging for assessment of ADCs. Radiology, 2009. 253(1): p. 144-52.
39.Chang, H.C., et al., Parotid fat contents in healthy subjects evaluated with iterative decomposition with echo asymmetry and least squares fat-water separation. Radiology, 2013. 267(3): p. 918-23.
40.Hao, W., et al., Influence of scan duration on the estimation of pharmacokinetic parameters for breast lesions: a study based on CAIPIRINHA-Dixon-TWIST-VIBE technique. Eur Radiol, 2015. 25(4): p. 1162-71.
41.Le, Y., et al., Improved T1, contrast concentration, and pharmacokinetic parameter quantification in the presence of fat with two-point dixon for dynamic contrast-enhanced magnetic resonance imaging. Magn Reson Med, 2015.