ABSTRACT
Objective To compare the value of apparent diffusion coefficient (ADC) value and the standardized apparent dif‐fusion coefficient (ADC) value in diagnosing malignancy degree of prostate cancer .Methods Diffusion weighted imaging (DWI) results of 34 patients with prostate cancer proved pathologically were retrospectively analyzed .The ADC values in 49 lesions and normal peripheral zones of the prostates of the patients were measured .Then ,ADC values of the lesions were calculated .According to the results of Gleason score ,the lesions were divided into 3 groups:Gleason score≤6 (low‐risk group) ,Gleason score=7 (inter‐mediate‐risk group) and Gleason score≥8 (high‐risk group) .Statistical analysis was performed to evaluate the differences of the ADC values and sADC values in three groups ,and to evaluate the correlation between Gleason score and ADC value or sADC value . Results There were statistically differences overall in ADC values and sADC values of the three groups (P 0 .05) ,however ,there were difference between sADC values of three groups each other (P0 .05) .However ,when change the specificity to 100% ,sADC had higher sensitivity than ADC values (47 .5% vs .5 .6% ,78 .2% vs .50 .9% ) in differentiating low‐risk from inter‐mediate‐risk group ,and low‐risk from high‐risk group .Conclusion ADC value and sADC value showed all negative correlation with Gleason score ,but sADC value may be of higher performance in diagnosing malignancy degree of prostate cancer .
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Objective To explore the diffusion-weighted magnetic resonance imaging (DWI) and apparent dispersion coefficient(ADC) value in cerebral infarction diagnosis and judgment of cerebral infarction outcome and staging of the value.Methods According to different stages,26 patients were divided into 3 phases,phase Ⅰ (6 ～72 h) had 11 cases,phase Ⅱ (4 ～ 10 d) had 12 cases,phase Ⅲ (10 d later) had 9 cases,of which 3 cases were reviewed,3 cases were recurrence of cerebral infarction.Each patient's MRI included T1 weighted imaging,T2 weighted imaging,DWI and ADC sequence scan image reconstruction,the ADC map obtained one regions of interest (ROI),and the mean ADC value of ROI were calculated,the average ADC value of the corresponding contralateral area were also calculated by the same method,and then the mean relative ADC value were calculated.Results DWI image of all cases showed high signal,11 cases showed high signal and 1 case showed low signal in phase Ⅱ.In phase Ⅲ,1 case showed normal signal and 1 case showed high signal,2 cases showed mixed signal,1 case were reduced,and the rest were all low signal.Compared with the contralateral corresponding region,the average ADC values were reduced in phase Ⅰ.The infarction average ADC values were 0.434 × 10 3mm2/s,0.653 × 10-3mm2/s,1.600 × 10-3mm2/s in phase Ⅰ,Ⅱ,Ⅲ respectively,and the average ADC values of contralateral corresponding region were 0.938 × 10-3 mm2/s,0.814 × 10-3 mm2/s,0.757 × 10-3 mm2/s respectively; the mean relative ADC values were (51.5 ±16.8)％,(79.2 ±30.0)％,(210.9 ±45.1)％ in phase Ⅰ,Ⅱ,Ⅲ respectively (P ＜ 0.05).Conclusion ADC value of cerebral lesions area and relative ADC value of the variation in time provides an objective basis for the diagnosis of DWI,contributes to timely and accurately determine the age of cerebral lesions and pathophysiology of the changes.
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Objective To explore the diagnostic value of MR diffusion weighted imaging (DWI) in the differential diagnosis between encephalitis and acute cerebral infarction.Methods The MR DWI appearances of 23 cases of encephalitis including 14 cases with viral encephalitis, 9 cases with demyelinative encephalitis and 30 cases with acute cerebral infarction were retrospectively analyzed.Results The 30 cases of acute cerebral infarction appeared bright signal in DWI with a ADC values of (0.46?0.13)?10 -3mm2/s. 7 cases with viral encephalitis and 9 cases with demyelinative encephalitis appeared slightly high or high signal intensity in DWI with a ADC values of (0. 98?0.18)?10 -3mm2/s and(0. 89?0.07)?10 -3mm2/s respectively. The ADC values of viral encephalitis and demyelinative encephalitis were higher comparing to acute cerebral infarction(?0.05). However, the ADC values showed higher or lower in different areas in 4 cases, and lower ADC values appearing in 3 cases with viral encephalitis comparing normal parenchyma.Conclusion MR DWI is useful in the differential diagnosis between encephalitis and acute cerebral infarction.