Value of Minimum Apparent Diffusion Coefficient in Peritumoral Edema in the Differential Diagnosis between Primary Central Nervous System Lymphoma and Glioblastoma / 中国医学科学院学报

Objective To evaluate the role of minimum apparent diffusion coefficient(MinADC) values in peritumoral edema based on magnetic resonance diffusion weighted imaging in the differential diagnosis between primary central nervous system lymphoma(PCNSL) and glioblastoma(GBM).Methods ADC values in peritumoral edema were measured in 16 patients with PCNSL(diffuse large B cell lymphoma) and 31 patients with GBM(WHO grade 4) confirmed by pathology.Regions of interests were manually drawn on ADC maps on peritumoral edema regions to obtain the MinADC value.Independent samples t-test and receiver operating characteristic analysis were performed for statistical analysis.Results The MinADC value [(1.20-1.45)×10 mm/s,mean(1.35±0.68)×10 mm/s] in PCNSL was significantly higher than that in GBM [(0.95-1.31)×10 mm/s,mean(1.12±0.09)×10 mm/s](t=9.977,P=0.000).The area under the receiver operating characteristic curve was 0.986,and the cutoff value of MinADC was 1.245×10 mm/s for the differentiation between PCNSL and GBM,with the best combination of sensitivity(94.1%) and specificity(94.1%).Conclusion MinADC value can be a simple and effective measure for the differential diagnosis between PCNSL and GBM.

Association of myocardial bridge of the left anterior descending coronary artery with coronary atherosclerotic stenosis in the segment proximal to the site of bridge / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate whether myocardial bridging (MB) is independently associated with coronary atherosclerosis proximal to MB in the left anterior descending coronary artery (LAD) identified by computed tomographic coronary angiography (CCTA).</p><p><b>METHODS</b>From March 2011 to December 2012, patients (n=9 862) with suspected coronary disease underwent CCTA using dual-source CT scanner. The baseline clinical characteristics (age, gender, smoking history, presence of hypertension, dyslipidemia, diabetes mellitus, family history of heart attack, and body mass index) and the results of CCTA were reviewed. Two radiologists evaluated the coronary artery for MB and coronary atherosclerosis stenosis (CAS) in LAD and made a diagnosis by consensus. Significant independent risk factors for CAS were investigated by multivariate logistic regression analysis.</p><p><b>RESULTS</b>A total of 3 182 (32.3%) cases of MB and 3 359 cases of CAS of LAD were identified. No patient with CAS in the tunneled segment was found. The mean length of bridges and the mean thickness of the overlying myocardium was (17.3±5.2) mm and (1.2±0.9) mm, respectively. There were 1658 MB cases in 3 359 cases of LAD stenosis and 1 524 MB cases in 6 503 cases of no LAD stenosis (χ(2)=681.12, P<0.05). Logistic regression analysis showed that MB in the LAD were significantly associated with CAS in the proximal LAD (OR=3.07, 95%CI=2.81-3.37, P<0.001), and after final adjustment for age, gender, body mass index, family history of heart attack, smoking, hypertension, dyslipidemia, diabetes mellitus, and resting heart rate (OR=2.86, 95% CI=2.60-3.16, P < 0.001).</p><p><b>CONCLUSION</b>MB in the LAD is independently associated with CAS in the proximal segment to MB.</p>

Differentiation between glioma recurrence and radiation-induced brain injuries using perfusion-weighted magnetic resonance imaging / 中国医学科学院学报

<p><b>OBJECTIVE</b>To evaluate the role of perfusion weighted imaging (PWI) in the differentiation between recurrent glioma and radiation-induced brain injuries.</p><p><b>METHODS</b>Twenty-three patients with previously resected and irradiated glioma, presenting newly developed abnormal enhancement, were included in the study. The final diagnosis was determined either histologically or clinicoradiologically. PWI was obtained with a gradient echo echo-planar-imaging (GRE-EPI)technique. The normalized relative cerebral blood volume (rCBV) ratio [rCBV (abnormal enhancement)/rCBV (contralateral tissue)], relative cerebral blood flow (rCBF) ratio [rCBF (abnormal enhancement)/rCBF(contralateral tissue)], mean transit time(MTT) ratio [MTT (abnormal enhancement)/MTT(contralateral tissue)],time to peak(TTP)ratio[TTP(abnormal enhancement)/TTP(contralateral tissue)],and bolus arrive time(BAT)ratio[BAT(abnormal enhancement)/BAT(contralateral tissue)] were calculated. The regions of interest (ROIs) consisting of 20-40mm(2) were placed in the abnormal enhanced areas on postcontrast T1-weighted images.Ten ROIs measurements were performed in each lesion.T test was used to determine whether there was a difference in the rCBV/rCBF/rMTT/rTTP/rBAT ratios between recurrent glioma and irradiated injuries.Significance was set to a P value <0.05.</p><p><b>RESULTS</b>Thirteen of the 23 patients were proved recurrent glioma and 10 were proved radiation-induced brain injuries. The rCBV ratio (3.60±3.86 vs. 0.82 ± 0.74, P = 0.000)and rCBF ratio (2.88 ± 2.27 vs. 0.84 ± 0.80, P = 0.000) in glioma recurrence were markedly higher than those in radiation injuries. The areas under rCBV and rCBF ROC curve were both 0.8763. rMTT (P=0.204), rTTP (P=0.260), and rBAT (P=0.071) ratios showed no statistical difference between the two groups.</p><p><b>CONCLUSION</b>PWI is an effective technique in distinguishing glioma recurrence from radiation injuries,and the ratios of rCBV and rCBF ratio differential diagnosis of critical value to 1.3088 and 1.1235, respectively, can be used as a reliable clinical indicator.</p>