Lactate dehydrogenase, a Risk Factor of Severe COVID-19 Patients

BACKGROUNDThe World Health Organization (WHO) has recently declared coronavirus disease 2019 (COVID-19) a public health emergency of global concern. Updated analysis of cases might help identify the characteristic and risk factors of the illness severity. METHODSWe extracted data regarding 47 patients with confirmed COVID-19 from Renmin Hospital of Wuhan University between February 1 and February 18, 2020. The degree of severity of COVID-19 patients (severe vs. non-severe) was defined at the time of admission according to American Thoracic Society (ATS) guidelines for community-acquired pneumonia (CAP). RESULTSThe median age was 64.91 years, 26 cases (55.31%) were male of which, and 70.83% were severe cases. Severe patients had higher APACHE II (9.92 vs 4.74) and SOFA (3.0 vs 1.0) scores on admission, as well as the higher PSI (86.13 vs 61.39), Curb-65 (1.14 vs 0.48) and CT semiquantitative scores (5.0 vs 2.0) when compared with non-severe patients. Among all univariable parameters, APACHE II, SOFA, lymphocytes, CRP, LDH, AST, cTnI, BNP, et al were significantly independent risk factors of COVID-19 severity. Among which, LDH was most positively related both with APACHE II (R = 0.682) and SOFA (R = 0.790) scores, as well as PSI (R = 0.465) and CT (R = 0.837) scores. To assess the diagnostic value of these selected parameters, LDH (0.9727) had maximum sensitivity (100.00%) and specificity (86.67%), with the cutoff value of 283. As a protective factor, lymphocyte counts less than 1.045 [x] 109 /L showed a good accuracy for identification of severe patients with AUC = 0.9845 (95%CI 0.959-1.01), the maximum specificity (91.30%) and sensitivity (95.24%). In addition, LDH was positively correlated with CRP, AST, BNP and cTnI, while negatively correlated with lymphocyte cells and its subsets, including CD3+, CD4+ and CD8+ T cells (P < 0.01). CONCLUSIONSThis study showed that LDH could be identified as a powerful predictive factor for early recognition of lung injury and severe COVID-19 cases. And importantly, lymphocyte counts, especially CD3+, CD4+, and CD8+ T cells in the peripheral blood of COVID-19 patients, which was relevant with serum LDH, were also dynamically correlated with the severity of the disease. FUNDINGKey Project of Shanghai Municipal Health Bureau (2016ZB0202)

A Fully Automatic Deep Learning System for COVID-19 Diagnostic and Prognostic Analysis

Coronavirus disease 2019 (COVID-19) has spread globally, and medical resources become insufficient in many regions. Fast diagnosis of COVID-19, and finding high-risk patients with worse prognosis for early prevention and medical resources optimization is important. Here, we proposed a fully automatic deep learning system for COVID-19 diagnostic and prognostic analysis by routinely used computed tomography. We retrospectively collected 5372 patients with computed tomography images from 7 cities or provinces. Firstly, 4106 patients with computed tomography images and gene information were used to pre-train the DL system, making it learn lung features. Afterwards, 1266 patients (924 with COVID-19, and 471 had follow-up for 5+ days; 342 with other pneumonia) from 6 cities or provinces were enrolled to train and externally validate the performance of the deep learning system. In the 4 external validation sets, the deep learning system achieved good performance in identifying COVID-19 from other pneumonia (AUC=0.87 and 0.88) and viral pneumonia (AUC=0.86). Moreover, the deep learning system succeeded to stratify patients into high-risk and low-risk groups whose hospital-stay time have significant difference (p=0.013 and 0.014). Without human-assistance, the deep learning system automatically focused on abnormal areas that showed consistent characteristics with reported radiological findings. Deep learning provides a convenient tool for fast screening COVID-19 and finding potential high-risk patients, which may be helpful for medical resource optimization and early prevention before patients show severe symptoms. Take-home messageFully automatic deep learning system provides a convenient method for COVID-19 diagnostic and prognostic analysis, which can help COVID-19 screening and finding potential high-risk patients with worse prognosis.

Volumetric evaluation of renal sinus adipose tissue on computed tomography images in bilateral nephrolithiasis patients.

PURPOSE: To compare renal sinus fat volume (RSFV) separately within the right and left kidneys between bilateral nephrolithiasis patients and healthy controls. METHODS: This cross-sectional study analyzed patients who underwent unenhanced abdominal computed tomography (CT) divided into nephrolithiasis (n = 102) and healthy control (n = 130) groups. Age, sex, blood pressure [systolic blood pressure (SBP) and diastolic blood pressure (DBP)], estimated glomerular filtration rate (eGFR), body weight, and height of each participant were extracted. Volumetric renal sinus adipose tissue was measured separately for both kidneys on CT images. Urea, serum creatinine (Scr), uric acid (UA), total serum cholesterol (TCH), serum triglyceride (TG), and serum high- and low-density lipoprotein (HDL and LDL, respectively) cholesterol levels were obtained. RESULTS: Overall, 232 participants (mean age 47 years, 50% women) were enrolled. There were no differences in sex, DBP, urea, and LDL-cholesterol between the two groups (all p > 0.05). However, nephrolithiasis patients had higher age, BMI, SBP, and RSFV; higher Scr, UA, TCH, and TG serum levels; and lower HDL-cholesterol level and eGFR. Average left RSFV was significantly higher than right RSFV in healthy controls (4.56 ± 2.29 versus 3.34 ± 1.90 cm3, p < 0.001). A significant relationship between bilateral RSFV, age, BMI, SBP, and eGFR was noted in bilateral nephrolithiasis patients. Multivariate linear regression analysis showed age, BMI, and LDL-cholesterol to be independent predictors of left RSFV, and only BMI was an independent predictor of right RSFV. CONCLUSIONS: Our data showed renal sinus adipose tissue accumulation and the relationship among RSFV, age, BMI, and LDL-cholesterol in bilateral nephrolithiasis patients.

Deep learning Enables Accurate Diagnosis of Novel Coronavirus (COVID-19) with CT images

BackgroundA novel coronavirus (COVID-19) has emerged recently as an acute respiratory syndrome. The outbreak was originally reported in Wuhan, China, but has subsequently been spread world-widely. As the COVID-19 continues to spread rapidly across the world, computed tomography (CT) has become essentially important for fast diagnoses. Thus, it is urgent to develop an accurate computer-aided method to assist clinicians to identify COVID-19-infected patients by CT images. Materials and MethodsWe collected chest CT scans of 88 patients diagnosed with the COVID-19 from hospitals of two provinces in China, 101 patients infected with bacteria pneumonia, and 86 healthy persons for comparison and modeling. Based on the collected dataset, a deep learning-based CT diagnosis system (DeepPneumonia) was developed to identify patients with COVID-19. ResultsThe experimental results showed that our model can accurately identify the COVID-19 patients from others with an excellent AUC of 0.99 and recall (sensitivity) of 0.93. In addition, our model was capable of discriminating the COVID-19 infected patients and bacteria pneumonia-infected patients with an AUC of 0.95, recall (sensitivity) of 0.96. Moreover, our model could localize the main lesion features, especially the ground-glass opacity (GGO) that is of great help to assist doctors in diagnosis. The diagnosis for a patient could be finished in 30 seconds, and the implementation on Tianhe-2 supercompueter enables a parallel executions of thousands of tasks simultaneously. An online server is available for online diagnoses with CT images by http://biomed.nscc-gz.cn/server/Ncov2019. ConclusionsThe established models can achieve a rapid and accurate identification of COVID-19 in human samples, thereby allowing identification of patients.

Clinical features and high resolution CT imaging findings of preliminary COVID-19 / 中华放射学杂志

Objective:To summarize the clinical and high resolution CT(HRCT) characteristics of 141 patients with COVID-19.Methods:From January 20 to 28, 2020, 141 COVID-19 patients, 77 males and 64 females, with a median age of 49 (9, 87), were enrolled in the study. The clinical features, laboratory test results and HRCT findings of all patients were analyzed retrospectively.Results:In all of the patients, the decreasing leukocyte countin 38 (26.95%) and lymphocyte ratio in 71 (50.35%), a fever over 37.5 ℃ in 139 (98.58%), coughing in 106 (75.18%), headache in 11 (7.80%), expectoration in 41 (29.08%), chest distress in 93 (65.96%), and diarrhea in 4 (2.84%) were found. The HRCT of all patients were abnormal, including ground glass opacity (GGO) with patchy opacity in 52 (36.88%) mainly distributed along subpleural area, GGO with focal consolidation in 23 (16.31%),small patchy opacity in 27 (19.15%),large patchy consolidation in 20 (14.18%),thickened bronchovascular bundleing and blood vessel crossing the lesion in 48 (34.04%), air bronchus sign in 5 (3.55%), small nodule in 7 (4.96%),fibrous stripes and reticular opacities in 5 (3.55%), bilateral pleural effusion in 7 (4.96%), and mediastinal or bilateral hilar lymphadenopathy in 4 (2.84%).Conclusions:The clinical and HRCT manifestations of COVID-19 are various. Under the specific epidemiological background of COVID-19, chest HRCT scan should be carried out as soon as possible for early warning of this disease.

Management strategies for three patients with gynecological malignancies during the outbreak of COVID-19 / 中华妇产科杂志

Objective:To explore the management strategies for patients with gynecological malignant tumors during the outbreak and transmission of COVID-19.Methods:We retrospectively analyzed the clinical characteristics, treatment, and disease outcomes of three patients with gynecological malignancies associated with COVID-19 in Renmin Hospital of Wuhan University, and proposed management strategies for patients with gynecological tumors underriskof COVID-19.Results:Based on the national diagnosis and treatment protocol as well as research progress for COVID-19, three patients with COVID-19 were treated. Meanwhile, they were also appropriately adjusted the treatment plan in accordance with the clinical guidelines for gynecological tumors. Pneumonia was cured in 2 patients, and one patient died of COVID-19.Conclusions:Patients with gynecological malignant tumors are high-risk groups prone to COVID-19, and gynecological oncologists need to carry out education, prevention, control and treatment according to specific conditions. While, actively preventing and controlling COVID-19, the diagnosis and treatment of gynecological malignant tumors should be carried out in an orderly and safe manner.

Clinical features and high resolutionCT imaging findings of preliminary diagnosis novel coronavirus pneumonia / 中华放射学杂志

Objective@#To summarize the clinical characteristics of 141 patients with novel coronavirus pneumonia (NCP) and the imaging characteristics of High Resolution CT(HRCT) in the chest.@*Methods@#From January 20, 2020 to 28, 141 NCP patients, 77 males and 64 females, with a median age of 49 (9,87), were retrospectively analyzed. The clinical features, laboratory examination indexes and HRCT findings of 141 NCP patients were analyzed.@*Results@#In 141 NCP patients, 38 (26.95%) had a decrease in leukocyte count and 71 (50.35%) had a decrease in lymphocyte ratio. Among 141 NCP patients, 139 (98.58%) had fever (over 37.5 ° C), 106 (75.18%) coughed, 11 (7.80%) had headache, 41 (29.08%) coughed up sputum, 93 (65.96%) had chest distress, and 4 (2.84%) had diarrhea. HRCT of 141 NCP patients were abnormal, 52 (36.88%) showed ground glass shadow (GGO) and patchy shadow, mainly subpleural distribution; 23 (16.31%) showed GGO with focal consolidation; 27 (19.15%) had small patchy blur; 20 (14.18%) had large patchy consolidation; 48 (34.04%) had bronchovascular bundle thickening and vascular perforator sign; 5 (3.55%) had Air bronchus sign; small nodule shadow in 7 cases (4.96%); fibrosis, grid shadow or strip shadow in 5 cases (3.55%); bilateral pleural effusion in 7 cases (4.96%); mediastinal or bilateral hilar lymphadenopathy in 4 cases (2.84%).@*Conclusions@#The clinical features and HRCT images of NCP are various. Under the specific epidemiological background of NCP, HRCT scan of chest should be carried out in time to make early warning of disease.

Application value of post-discharge chest low-dose CT for patients with COVID-19 / 中华放射医学与防护杂志

Objective:To explore the value of chest low-dose CT (LDCT) in post-discharge follow-up assessments of patients with coronavirus disease 2019 (COVID-19).Methods:The chest CT findings of 58 patients with COVID-19 from March 17 to March 25, 2020 at Remin Hospital of Wuhan University were retrospectively analyzed. Two radiologists independently scored the subjective image quality on a 5-point Likert scale. The signal-to-noise ratio (SNR) and SD air of images and the CT radiation dose parameters were calculated, including the CT volume dose index (CTDI vol), dose length product (DLP), and effective radiation dose ( E). Results:The subjective image quality scores on CT images obtained before and after discharge by readers 1 and 2, were 4.45±0.22, 3.88±0.33 ( P>0.05) and 4.37±0.18, 3.91±0.35 ( P>0.05), respectively. The SNR and SD air in LDCT after discharge were 4.39±0.95 and 7.19±2.41, which were significantly lower than those in routine chest CT before discharge (5.14±1.06, Z=-5.551, P<0.001; 6.48±1.57, Z=-3.217, P<0.001). All of the obtained images were sufficient for diagnosis. The CTDI vol, DLP, and E in LDCT were significantly lower than those in routine CT [(2.41±0.09), (10.53±1.03)mGy, Z=-6.568, P<0.001; (88.03±5.33), (338.74±34.64)mGy·cm, Z=-6.624, P<0.001; and (1.23±0.17), (4.74±0.48)mSv, Z=-5.976, P<0.001]. Conclusions:Patients with COVID-19 can be followed up with low-dose chest CT after discharge.

The application value of low-dose CT scan in pregnant women with COVID-19 / 中华放射医学与防护杂志

Objective:To explore the value of low-dose CT in pregnancy with COVID-19.Methods:A retrospective analysis was performed on the clinical characteristics, laboratory tests, and chest CT findings of 12 pregnant women with COVID-19 diagnosed by nucleic acid testing in the Renmin Hospital of Wuhan University from January 20, 2020 to February 16, 2020. Two radiologists blinded to the reconstruction algorithm independently scored subjective image quality on a 5-point Likert scale. Image quality score ≥ 3 was acceptable in clinics. The CT radiation doses were recorded, including CT volume dose index (CTDI vol), dose length product (DLP), and effective radiation dose ( E). Two radiologists observed the distribution, shape, density, and other characteristics of lung lesions, and they also decided whether hilar, mediastinal lymphadenopathy, and pleural changed. Results:A total of 12 pregnant women with COVID-19, 8 had cough, 4 had fever, 2 had chest tightness, and 1 had dyspnea and diarrhea each. The CT image quality score of all patients was 3-4, with an average of 3.46, which fully met the clinical diagnosis requirements. The CTDI vol value was 1.13-4.31 mGy, with an average of 3.02 mGy. The DLP value was 34.48-75.29 mGy·cm, with an average of 55.48 mGy·cm. The Evalue was 0.48-1.05 mSv, with an average of 0.78 mSv. In all cases, chest CT examination showed abnormal manifestations after clinical symptoms, including unilateral lung lesions in 5 cases and bilateral lung lesions in 7 cases, 1 case of ground-glass opacity, 1 case of solidification, 7 cases of ground-glass and consolidation, 1 case of strip opacity, ground-glass, and consolidation and strip cable shadow coexisted in 2 cases. Conclusions:The application of low-dose CT scan in pregnant women with COVID-19 is completely feasible. CT mainly manifested as bilateral lung patchy and flaky ground-glass opacity with consolidation. Active and effective treatment can help recover and improve prognosis.

Reproducibility and Risk Factors of Aortic Distensibility Quantification in Abdominal Aortic Aneurysm Using Multi-slice Spiral CT / 中国医学影像学杂志

Purpose To investigate the reproducibility and risk factors of aortic distensibility quantification in patients with abdominal aortic aneurysm using multi-slice spiral CT.Materials and Methods The abdominal aortic computed tomography angiography data of 54 patients with infrarenal abdominal aortic aneurysm were prospectively studied.64-muti detector spiral CT,retrospective ECG-gating and segment data collecting scanning were all carried out.The aortic distensibility,D value,and pulse wave velocity at renal artery level and infrarenal artery level were calculated using semiautomatic segmentation software.The difference of aortic distensibility at different levels was compared,and consistency test was performed.Results The D value at renal artery level and infrarenal artery level of abdominal aortic aneurysm was (1.05 ±0.22)×10-5/Pa and (0.49± 0.18)× 10-5/Pa,respectively;and the corresponding pulse wave velocity was (9.68± 1.09) m/s and (14.96 ±4.01) m/s,respectively.The intraclass correlation coefficient of intra-and interobserver at renal level was 0.92 and 0.79,while it was 0.85 and 0.79 at inffa level.The Bland-Altman graph showed that the vast majority of points were within the 95％ CI,the difference of intraobserver between the two positions was 0.017×105/pa and 0.010×10-5/Pa,and the difference of interobserver was 0.013×105/Pa and 0.018×10-5/Pa.Multivariate analysis of all these variables showed aortic distensibility to be independently correlated to body mass index,pulse pressure,diastolic pressure and abdominal aortic aneurysm diameter (R2=0.68).Conclusion The quantification of aortic distensibility using multi-slice spiral in patients with abdominal aortic aneurysm shows high stability.Taking into consideration of the relationship between different risk factors and the incidence of abdominal aortic aneurysm can lead to a better clinical approach.

Effect of inversion time on flow-sensitive alternating inversion recovery perfusion imaging of spinal bone marrow / 中华放射学杂志

Objective To investigate the effect of inversion time (TI) on flow-sensitive alternating inversion recovery (FAIR) perfusion imaging of spinal bone marrow (SBM),and evaluate the reproducibility of blood flow (BF) measurements using this technique.Methods Twenty four healthy volunteers without lumbar and other disease with clinical and MR studies were prospectively included.The first 14 healthy volunteers were included to study the effect of TI on ASL perfusion imaging of SBM to get the optimized TI,the remaining 10 volunteers were included to investigate the reproducibility of the SBM arterial spin labeling (ASL) scan protocol.The optimized TI of FAIR spinal bone marrow perfusion experiment was carried out on 14 healthy volunteers on 3.0 T magnet,two adjacent vertebral bodies were orderly selected from each volunteer to measure the △M and the SNR of FAIR perfusion MRI with 5 different TIs (800,1 000,1 200,1 400,1 600 ms),and the vertebral bodies selected order were determined by the order of the subjects enrolled.In addition,FAIR perfusion spinal vertebral BF measurements were repeated in last l0 healthy subjects on L4 or L5 by reposition immediately,paired t test and reproducibility statistics (included within-patient standard deviation (wSD) and within-patient coefficient of variation (WCV)) were used to analyze the test-retest experiment reproducibility.Result TI optimization experiments total included 28 vertebral bodies,when TI (ms) was chose as 800,1 000,1 200,1 400,1 600,ms respectively,the mean △M of spinal bone marrow were 20.8±9.0,29.0± 10.9,36.4± 12.5,26.2± 10.2 and 23.8± 11.5,and the mean SNR were 2.0± 1.0,2.3±0.8,2.4± 1.0,2.3±0.8 and 2.0±0.7.With TI increasing,AM and SNR increased first and then decrcascd,the maximum values of both were achieved when the TI near 1 200 ms.Test-retestexperimcnt were carried on 10 vertebral bodies eventually,and two measurements of spinal vertebral BF perfusion before and after were (108.9±4.6)and (109.2 ±4.6)ml · 100g-1· min 1,respectively,and no significant difference was found (t=-0.157,P=0.879),wCV of the measurements was 3.28％ (3.57/109.06).Conclusion The optimal TI was 1 200 ms for spinal bone marrow ASL perfusion image,at which the maximum AM,higher SNR,and good reproducibility for the FAIR spinal bone marrow perfusion imaging can be achieved.

Comparison of standard-dose and low-dose scanning with 16-MDCT for urinary calculi / 中华放射医学与防护杂志

Objective To explore the feasibility to diagnose ureterolithiasis by 16-multidetector spiral computed tomography (16-MDCT) at different low doses based on body mass index (BMI).Methods A total of one hundred patients from 2009 Sep to 2010 Feb suspected of ureterolithiasis were randomly divided into 2 equal groups undergoing 16-MDCT at standard-dose (120 kV, 240 mA) or lowdose (120, 80, and 50 mA, respectively) based on the body mass index (BMI).Taking the clinical diagnosis as the standard, the sensitivity level, specificity level, and positive predictive value of these groups were compared.Results The dose length product ( DLP ) of the low-dose CT group and the average CT dose index (CTDIvol ) were 18.95 and 6.65 mGy, respectively.There was significant difference between the two groups ( t = 31.78, P ＜ 0.01 ).The sensitivity level, specificity level, and positive predictive value of the low-dose group were 97.1% , 94.0% , and 94.3% , respectively, all not significantly different from those of the standard-dose groups (97.3% , 96.0% , and 97.3% , respectively,P ＞0.05).Conclusions It is feasible to diagnose ureterolithiasis by low-dose 16-MDCT based on BMI with the obtained image quality meeting the clinical diagnostic requirements.

Hippocampal volume MRI and 1H-MRS study in chronic alcohol dependent patients / 中华放射学杂志

Objective To observe the changes of the bilateral hippocampal volume (BHV) and 1H-MRS appearance of chronic alcohol dependent (CAD) patients and to provide quantitative information for the clinical diagnosis of CAD. Methods The conventional MR imaging including three-dimensional fast spoiled gradient recalled echo (3D-FSPGR) and 1H-MRS were performed on 16 patients with CAD (CAD group)and 18 cases of volunteer ( control group). The BHV were measured in both groups and the standardized BHV in CAD group and control group were compared. 1H-MRS metabolites including N-acetylaspartate (NAA), Choline compounds (Cho), Creatine (Cr), and myoinositol (mI) of the bilateral cephalic hippocampus were acquired. The ratios of Cho/Cr, Cho/NAA, NAA/Cr and mI/Cr within the bilateral cephalic hippocampus of the two groups were compared. The t test was used to compare the BHV and the ratios of 1H-MRS in the bilateral cephalic hippocampus between the two groups. Results In CAD group,the left and the right hippocampal volume were 1. 881 ±0. 292, 2. 139 ±0. 328 respectively while they were 2. 106 ±0. 245 and 2. 267 ±0. 271 respectively in the control group. The BHV had no significant difference between the left and the right in either the CAD group or the control group (t =0. 232, 0. 147 respectively,P ＞ 0. 05). The BHV had no significant difference between the CAD group and control group(t = 0. 424,0. 131 respectively ,P ＞0. 05 ). The Cho/Cr and NAA/Cr in the right cephalic hippocampus of the CAD group were 1. 225 ±0. 210 and 1. 145 ±0. 034 respectively, while they were 1. 429 ±0. 286, 1. 612 ±0. 444 respectively in the control group(t =0. 321,0. 408 ,P ＜0. 05 ). The Cho/NAA, mI/Cr in the right cephalic hippocampus and the Cho/Cr, Cho/NAA, NAA/Cr and mI/Cr in the left cephalic hippocampus between the two groups had no statistically significant difference. Conclusion 1H-MRS could potentially provide early diagnostic evidence for CAD patients before the onset of cerebral morphological changes.

Reduction in thyroid dose from neck CT angiography with 64-slice spiral CT with automatic tube current modulation technique / 中华放射医学与防护杂志

Objective To assess the effectiveness of Z-axis automatic tube current modulation ( ATCM) technique with respect to dose reduction and image noise in the thyroid regional tissues during neck computed tomography angiography (CTA). Methods A total of 140 patients underwent neck CTA with 64-slice spiral CT, and were randomized into fixed-tube current group and ATCM group. Objective noise, CTDIw, DLP and mA of each group were recorded. Results The image qualities of all the patients were diagnostically acceptable, though the objective noise of neck in the ATCM group was higher than that in the group of fixed-tube current (P＜ 0.05 ). The radiation doses in the ATCM group [ CTDIw (35.99±1.31 ) mGy, DLP (11 121.39 ±5.51) mGy·cm] were significantly inferior to those in the group of fixed tube current [ CTDIw (43.22±1.42) mGy, DLP (1514.45±5.56) mGy·cm]. Conclusions Compared with fixedtube current technique, ATCM technique could significantly reduce the radiation dose in neck CT with diagnostic acceptability of the image quality.

Dynamic Contrast Enhanced Magnetic Resonance Imaging of Diffuse Spinal Bone Marrow Infiltration in Patients with Hematological Malignancies

OBJECTIVE: To investigate the significance of the dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) parameters of diffuse spinal bone marrow infiltration in patients with hematological malignancies. MATERIALS AND METHODS: Dynamic gadolinium-enhanced MR imaging of the lumbar spine was performed in 26 patients with histologically proven diffuse bone marrow infiltration, including multiple myeloma (n = 6), acute lymphoblastic leukemia (n = 6), acute myeloid leukemia (n = 5), chronic myeloid leukemia (n = 7), and non-Hodgkin lymphoma (n = 2). Twenty subjects whose spinal MRI was normal, made up the control group. Peak enhancement percentage (Emax), enhancement slope (ES), and time to peak (TTP) were determined from a time-intensity curve (TIC) of lumbar vertebral bone marrow. A comparison between baseline and follow-up MR images and its histological correlation were evaluated in 10 patients. The infiltration grade of hematopoietic marrow with plasma cells was evaluated by a histological assessment of bone marrow. RESULTS: Differences in Emax, ES, and TTP values between the control group and the patients with diffuse bone marrow infiltration were significant (t = -11.51, -9.81 and 3.91, respectively, p 0.05). A positive correlation was found between Emax, ES values and the histological grade of bone marrow infiltration (r = 0.86 and 0.84 respectively, p < 0.01). A negative correlation was found between the TTP values and bone marrow infiltration histological grade (r = -0.54, p < 0.01). A decrease in the Emax and ES values was observed with increased TTP values after treatment in all of the 10 patients who responded to treatment (t = -7.92, -4.55, and 5.12, respectively, p < 0.01). CONCLUSION: DCE-MRI of spine can be a useful tool in detecting diffuse marrow infiltration of hematological malignancies, while its parameters including Emax, ES, and TTP can reflect the malignancies' histological grade.

Logistic regression analysis of non-enhanced MR imaging,static and dynamic enhanced MR imaging in prediction of malignancy of vertebral compression fractures / 重庆医科大学学报

Objective:To evaluate non-enhanced MR imaging,static and dynamic enhanced MR imaging in differentiation of be-nign from malignant vertebral compression fractures and to evaluate which MR imaging parameters are most predictive of malignancy.Methods:Non-enhanced MR imaging,static and dynamic gadolinium-enhanced MR imaging were performed on 43 patients with acute osteoporotic compression fracture and 49 patients with malignant compression fracture proved by clinical follow-up and/or histologic findings.Binary multivariate logistic regression analysis was used to identify the best combination of MR imaging parameters that might be predictive of malignancy.Subjective overall performance of diagnostic models for sensitivi-ty,specificity and accuracy was evaluated with receiver operating characteristic curve(ROC).Results:Univariate analysis showed that the frequency distribution of MR imaging parameters including T1 weighted imaging homogeneity of vertebrae,convex pos-terior of vertebrae,retropulsion of the posterosuperior angle of vertebrae,pedicle involvement,epidural soft tissue mass,paraverte-bral soft tissue lesions,pattern of enhancement of vertebrae,pattern of enhancement of paravertebral soft tissue lesions,start of dynamic enhancement and pattern of time-intensity curve(TIC) were different between benign and malignant compression frac-ture(P0.05).ROC analysis showed that combined non-enhanced,static and dynamic enhanced MR imaging parameters(model 3) were superior to non-enhanced MR imaging pa-rameter(smodel 1)iction of malignancy.The sensitivity,specificity and accuracy of model 3 were 81.6%,90.7% and 85.9%,respec-tively.Multivariate logistic regression analysis revealed the most discriminating parameters were pedicle involvement,pattern of enhancement of vertebrae and pattern of TIC(OR value were 3.558,4.666 and 0.007,respectively,P