[雙語翻譯]--醫(yī)學(xué)外文翻譯--表觀擴散系數(shù)對肝臟良惡性腫塊的鑒別（英文）

1、RADIOLOGY—ORIGINAL ARTICLEValue of apparent diffusion coefficient measurement for discrimination of focal benign and malignant hepatic massesO Kilickesmez,1 S Bayramoglu,2 E Inci2 and T Cimilli21Department of Radiology,

2、School of Medicine, Yeditepe University and 2Department of Radiology, Istanbul Bakirkoy Dr. Sadi Konuk Training andResearch Hospital, Istanbul, TurkeyO Kilickesmez MD; S Bayramoglu MD;E Inci MD; T Cimilli MD.Corresponden

3、ceDr Ozgur Kilickesmez, Department ofRadiology, School of Medicine,YeditepeUniversity, Devlet Yolu Ankara Street 102/104,Kozyatagi 34752, Istanbul, Turkey.Email: okilickesmez@yahoo.comConflicts of interest: None.Submitte

4、d 30 July 2008; accepted31 July 2008.doi:10.1111/j.1754-9485.2009.02036.xSummaryThe purpose of our study was to investigate the value of diffusion-weighted mag-netic resonance imaging (DW-MRI) to discriminate benign and

5、malignant focallesions of the liver using parallel imaging technique. A total of 77 patients and65 healthy controls were enrolled in the study. DW-MRI was performed withb-factors of 0, 500 and 1000 s/mm2, and the apparen

6、t diffusion coefficients(ADC) values of the normal liver and the lesions were calculated. The meanADC value of the focal liver lesions were as follows: simple cysts(3.16 ± 0.18 ? 1023 mm2/s), hydatid cysts (2.58

7、77; 0.53 ? 1023 mm2/s), he-mangiomas (1.97 ± 0.49 ? 1023 mm2/s), metastases (1.14 ± 0.41 ? 1023mm2/s) and hepatocellular carcinomas (HCC) (1.15 ± 0.36 ? 1023 mm2/s).The mean ADC values of all the disease g

8、roups were statistically significant whencompared with the mean ADC value of the normal liver (1.56 ± 0.14 ? 1023mm2/s), (P < 0.01). There were also statistically significant differences amongthe ADC values of he

9、mangiomas and HCC metastases (P < 0.01), and simple andhydatid cysts (P < 0.008). However, there was no statistically significant differ-ence between HCC and metastases. The present study showed that ADC meas-ureme

10、nt has the potential to differentiate benign and malignant focal hepaticlesions. We propose to add DW sequence in the MR protocol for the detectionand quantitative discrimination of hepatic pathologies.Key words: abdomen

11、; diffusion-weighted imaging; liver; magnetic resonanceimaging.IntroductionMagnetic resonance imaging is considered the most accu-rate modality to image the liver for detection and character-ization of diffuse and focal

12、liver diseases and to discriminatebenign from malignant tumors, reflecting its ability on thebasis of various data acquired, such as T1, T2, and early andlate post-gadolinium images.1,2 Characterization of focalliver les

13、ions is very important because patients with knownprimary malignant neoplasms often have benign focal liverlesions, which must be differentiated from metastases. Thelack of ionizing radiation with MR imaging and the safe

14、ty ofgadolinium chelates, as compared with iodinated contrastagents, are two important considerations for the preferen-tial use of MR imaging over CT scanning in the investigationof liver disease.3 Furthermore, DWI has e

15、merged as a newdiagnostic tool with the ability to detect focal lesions and todiscriminate malignant ones without the need for contrastmaterial.4–7 We aimed to investigate whether DWI has theability to detect malignancy

16、and to discriminate metastasesand hepatocellular carcinomas.MethodsThis was a retrospective study conducted at our institutionbetween January 2006 and March 2007. A total of 77patients (42 women, 35 men; mean age, 59 yea

17、rs) and65 healthy controls (35 women, 30 men; mean age,35 years) with completely normal liver MRI and laboratoryfindings were enrolled in the study. The research protocolwas approved by the ethics committee of our instit

18、ution.Written consent was obtained from all patients prior tocommencement of the study.Magnetic resonance imaging was performed on a 1,5 Tbody scanner (Avanto; Siemens, Erlangen, Germany)Journal of Medical Imaging and Ra

19、diation Oncology 53 (2009) 50–5550ª 2009 The AuthorsJournal compilation ª 2009 The Royal Australian and New Zealand College of Radiologistsclosest three measurements. In the patient group, a free-hand ROI was d

20、efined for the lesions detected on theT2-weighted EPI image (b = 0), while referring to theconventional sequences for verification of the lesionboundaries. The ROI was then copied to the correspond-ing ADC map.Statistica

21、l analysisAll statistical analyses were performed using SPSS(Statistical Package for Social Sciences) for Windows 10.0.The ADC values of cases are reported as the mean ±stand-ard deviation. Variance analysis and pai

22、red samples testwere also conducted for comparison of segments of abdom-inal organs. A P-value of less than 0.05 was considered toindicate a statistically significant difference.ResultsApparent diffusion coefficient valu

23、es of all the patientswho underwent conventional and diffusion-weighted MRexaminations are listed as box plots in Figure 1.The mean ADC value of the liver lesions wereas follows (Table 1): simple cysts, 20 cases (3.16 &#

24、177;0.18 ? 1023 mm2/s); hydatid cysts, 13 cases (2.58 ±0.53 ? 1023 mm2/s); hemangiomas, 15 cases (1.97 ± 0.49 ?1023 mm2/s); metastases, 13 cases (1.14 ± 0.41 ?1023 mm2/s); and hepatocellular carcinomas (HC

25、C) 13 cases(1.15 ± 0.36 ? 1023 mm2/s). The mean ADC values ofall of the disease groups were statistically significantwhen compared with mean ADC value of the normal livergroup (1.56 ± 0.14 ? 1023 mm2/s), (P <

26、; 0.01). Therewere also statistically significant differences among theADC values of hemangiomas and HCC metastases(P < 0.01), and simple and hydatid cysts (P < 0.008).However, there was no statistically significan

27、t differencebetween HCC and metastases.Representative cases are shown in Figures 2–5.DiscussionDiffusion is the term used to describe the random(Brownian) motion of water molecules.8 With a very strongbipolar gradient pu

28、lse inserted into either a spin-echo pulsesequence (i.e. Stejskal-Tanner technique) or a gradient-echo pulse sequence, MR imaging can be made sensitiveto the diffusion of water molecules in the tissue.6,9 Diffusionrestri

29、ction increases in highly cellular tissues; in contrast, itdecreases in low cellular tissues with large extracellularspace or with broken-down cellular membranes.7Studies have been published concerning the diffusionprope

30、rties of focal hepatic lesions. Most of the studiesrevealed that ADC values of benign lesions (cysts andhemangiomas) were significantly higher than those ofmalignant lesions attributed to high cellularity of malig-nant m

31、asses.10–12As with the previous studies, we found that hepaticcysts had the highest ADC because of their fluid content,with non-restricted motion of water molecules.4,10Table 1. ADC values of the focal liver lesionsLesio

32、ns N Mean ADC (mm2/s)Normal liver 65 1.56 ± 0.14 ? 1023 mm2/sSimple cysts 20 3.16 ± 0.18 ? 1023 mm2/sHydatid cysts 13 2.58 ± 0.53 ? 1023 mm2/sHemangiomas 15 1.97 ± 0.49 ? 1023 mm2/sHepatocellular carc

33、inomas 13 1.15 ± 0.36 ? 1023 mm2/sMetastases 13 1.14 ± 0.41 ? 1023 mm2/sADC, apparent diffusion coefficients.Fig. 2. Forty year-old woman with hemangioma.(a) Axial FS T2W image reveals a marked hyper-intense le

34、sion. (b) Axial diffusion-weighted(b = 1000 s/mm2) image reveals moderate hyper-intensity. (c) Apparent diffusion coefficients (ADC)were calculated. Tumor on ADC image shows mildhyperintensity (slightly increased diffusi

35、on) com-pared with normal parenchyma. Region of interestwas placed on mass (ROI 1,c). ADC of lesion was1.92 ? 1023 mm2/s.O Kilickesmez et al.52ª 2009 The AuthorsJournal compilation ª 2009 The Royal Australian a