| Objective:To evaluate the characteristics of MR imaging of hepatic lesions by using measurement of ADC value of hepatic lesions on the DWI imaging, and the Tl value, T2value on Non-enhanced imaging.Materials and Methods:(1)MR diffusion-weighted images and non-enhanced images were obtained in 127 patients.The age of these patients (105 men and 22 women) ranged from 24 to 89 years old (mean age, 50.18 years old), in eluding: heoatocellular carcinoma in 29, hepatic metastase in 24, hepatic cavernous hemangioma in 28, hepatic cyst in 19, Cirrhosis of liver in 24 , fatty liver in 3.(2)A11 MR images were obtained by a body coil in 1.51 superconduct MR system (Signa, Horizon LX, GE American).The imaging parameters in Tl weighted imaging with SE sequence were as follows: a TR of 500,300 msec, a TE of 15 msec, a section thickness of 8 mm with 2mm interslice gap, 10-15 acquired sections, a field of view of 36 × 36cm, a matrix of 256 × 128, two excitations, imaging time is 2 min 39 sec and 1 min 43 sec respectively. The imaging parameters in T2 weighted imaging with single-shot SE-EPI sequence were as follows: a TR of 4000 msec, a TE of30,60,90,120 msec,a section thickness of 8 mm with 2mm interstice gap, 10-15 acquired sections, a field of view of 44 × 44cm, a matrix of 128×192, two excitations, imaging time is 8 sec .The imaging parameters in Diffusion weighted imaging with SE-EPI sequence were as followsra TR of 10000 msec, a TE of 90msec,a section thickness of 8 mm with 2mm interslice gap, 10-15 acquired sections, a field of view of 36 X 36cm, a matrix of 128 X 128, one excitations,using four gradient factor and 3 dimension, imaging time is 40 sec.(3)To measure the signal intensity of non-enhanced imaging of hepatic lesions on T1WI and T2WI, T1 value and T2 value were evaluated with Matlab 5.3 software and Bloch equation: I=K × [1-exp(-TR/T1)] × exp(-TE/T2).(4) To measure the signal intensity of hepatic lesions on diffusion weighted imaging, ADC value were evaluated with the following equation: ADC=(ln[Si/Sh])/ (bh-bt) .(5)A11 the data in our study were performed statistical analysis using SPSS 10.0 version software package.Stardard descriptive statistical mean +SD were obtained, two-tailed test was used to compare every rank data respectively. Statistical significant difference, very significant difference and tendency were declared at a level of 0.5,0.05 and 0.001 respectively.Results:(l)Average ADC values of hepatic lesions were as follows: heoatocellular carcinoma (0.99 ±0.26) × 10-3mm2/sec, hepatic metastase: (1.17 ± 0.32) × 10~3mm2/sec, hepatic cavernous hemangioma: (1.81 ± 0.42) × 10"3mm2/sec, hepatic cyst: (3.11 ± 0.38) × 10"3mm2/sec, Cirrhosis of liver: (0.92 ± 0.25) × 10-3mm2/sec, fatty liver: (1.3 7 ±0.32) ×10-3mm2/secoThe ADC value of solid lesions were significantly lower than those of other hepatic lesions (p<0.05) The ADC value of cysts were significantly higher than those of other hepatic lesions (p<0.05), hepatic cavernous-7-hemangioma between hepatic solid lesions and hepatic cyst.(2) Average T1 value and T2 value of hepatic lesions were as follows : heoatocellular carcinoma 843.92 ± 167.75ms and 73.90 ± 14.21ms, hepatic metastase: 946.89± 186.13ms and 76.39± 19.76ms, hepatic cavernous hemangioma: 1102.33±213.12ms and 142.32±28.51ms, hepatic cyst: 1516.32±617.84msand247.33±112.52ms, Cirrhosis of liver-. 909.93±174.17ms and 59.54± 18.31ms, fatty liver: 493.82± 156.87ms and 64.38± 14.97ms0HCH and HCY had significantly prolonged T2 value relative to HCC and HMC.(3)The ADC value of various hepatic lesions were as follows (b=0mm2/sec, 100 mm2/sec, 500 mm2/sec, 1000 mm2/sec): heoatocellularcarcinoma: (0.58-1.31) ×mni2/sec , (0.61-1.29) × mm2/sec and(0.59-1.21)×mm2/sec, hepatic metastase: (0.71-1.62)×mm2/sec,(0.72-1.55)×mm2/sec and (0.75-1.31)×mm2/sec, hepatic cavernoushemangioma: (1.34-2.54)× mm2/sec, (1.38-2.43)× mm2/sec and(1.46-2.14) ×mm2...
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