CT spectral curve in differentiating spinal tumor metastasis and infections / 北京大学学报(医学版)

OBJECTIVE@#To evaluate the value of CT spectral curve in differentiating spinal tumor metastasis (STM) from spinal infections (SI).@*METHODS@#In the study, 29 STM and 18 SI patients proved pathologically and clinically were examined by dual energy spectral CT (DESCT). The monochromatic images and CT spectral curves were generated automatically by GSI Viewer software. The attenuation values at different energy levels (40-140 keV, every 10 keV), the attenuation values of the lesions on the conventional polychromatic CT images and the gradients of the curve were calculated and compared between STM and SI.@*RESULTS@#The median age of STM and SI (58 years vs. 64 years) were not significantly different (U=171, P=0.4). The attenuation values of STM at 40-100 keV were 281.79 (143.67, 446.19) HU, 199.68 (100.04, 321.49) HU, 151.54 (81.47, 243.49) HU, (122.64±27.72) HU, (99.90±23.88) HU, (85.82±21.61) HU, and (75.94±20.27) HU, respectively, which were significantly higher than SI: 185.29 (164.19, 277.03) HU, 138.44 (124.98, 238.56) HU, 105.46 (92.94, 169.53) HU, (93.77±15.55) HU, (79.15±12.84) HU, (68.99±11.75) HU, and (62.22±11.71) HU (all P < 0.05). The attenuation values at 110-140 keV and the attenuation value on the conventional CT images were not significantly different between STM and SI. The gradient of CT spectral curve of STM was 2.43±0.58, which was higher than the value of 1.50±0.40 for SI (P < 0.001). Using 1.72 and 248.80 HU as the threshold value for CT spectral curve slope and the attenuation value at 40 keV, could obtain the area under receiver operating characteristic (ROC) curve of 0.905 and 0.892, sensitivity of 88.0% and 80.0%, and specificity of 76.9% and 92.3%.@*CONCLUSION@#CT spectral curve provides valuable semi-quantitative information for the differential diagnosis of STM and SI, which can be used as a supplement to traditional CT imaging.

Applications of Artificial Intelligence in Musculoskeletal System Imaging / 中国医学科学院学报

Artificial intelligence (AI) represents the latest wave of computer revolution and is considered revolutionary technology in many industries including healthcare. AI has been applied in medical imaging mainly due to the improvement of computational learning,big data mining,and innovations of neural network architecture. AI can improve the efficiency and accuracy of imaging diagnosis and reduce medical cost;also,it can be used to predict the disease risk. In this article we summarize and analyze the application of AI in musculoskeletal imaging.

A Prospective Randomized Multicenter Controlled Trial on Salvianolate for Treatment of Unstable Angina Pectoris in A Chinese Elderly Population / 中国结合医学杂志

OBJECTIVE@#To evaluate the efficacy and safety of salvianolate in elderly patients with unstable angina pectoris (UAP).@*METHODS@#A prospective double-blind randomized placebo-controlled multicenter trial in elderly patients with UAP from 13 third-grade class-A hospitals in China was performed. A total of 318 patients were randomly allocated in a 1:1 ratio to an experimental group (160 patients) and a control group (158 patients). The experimental group was treated with salvianolate for 14 days on the basis of conventional medicine, and the control group was given a placebo for 14 days with the same criteria. Follow-up was lasted 28 days in both groups. The primary endpoint was biweekly frequency of angina pectoris attacks. The secondary endpoints included biweekly dosage of nitroglycerin, the Seattle Angina Questionnaire, angina pectoris severity and duration, myocardial injury markers, high-sensitivity C-reactive protein (hs-CRP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP), as well as major adverse cardiovascular events (MACEs). Safety was assessed according to adverse events and serious adverse events.@*RESULTS@#Baseline characteristics were similar between treatment groups. Compared with those in the control group, the frequency of biweekly angina attacks (2.92 vs . 4.08, P=0.025), the biweekly dosage of nitroglycerin, as well as the severity and duration of angina attacks (P<0.01) were reduced by salvianolate. The Seattle Angina Questionnaire score was also significantly improved in the experimental group than in the control group (P<0.05). No significant differences were observed between the two groups with respect to the incidence of MACEs. Salvianolate was well tolerated.@*CONCLUSIONS@#Salvianolate appear to have efficacy and well tolerated for elderly patients with UAP. [ClinicalTrials.gov identifier: NCT03037047].

Cerebral blood flow measurements in patients with comorbid hypertension and depression using 3D arterial spin labeling / 北京大学学报(医学版)

OBJECTIVE@#To evaluate cerebral blood flow (CBF) in patients with comorbid hypertension in depression using 3D pseudocontinuous arterial spin labeling (3D pcASL) and to compare the differences of CBF values in depression, hypertension, and comorbid hypertension between depression and healthy control groups. To investigate the correlation between CBF values and degrees of depression.@*METHODS@#Sixteen patients with depression (depression group, 3 males and 13 females, age range of 42-72 years old), sixteen patients with hypertension (hypertension group, 3 males and 13 females, age range of 41-68 years old), sixteen patients with comorbid hypertension in depression (comorbidity group, 3 males and 13 females, age range of 45-74 years old), and sixteen healthy controls (control group, 3 males and 13 females, age range of 43-68 years old) were recruited. 3D pcASL sequence was performed by GE 3.0T magnetic resonance scanner and CBF map was generated automatically. Statistical parametric mapping (SPM8) was performed to preprocess the CBF map, which was spatially normalized and smoothed. Comparison of the CBF values among the four groups was conducted by ANOVA. Correlation between the average CBF values in areas of decreased CBF and Hamilton depression scale (HAMD-17) was investigated.@*RESULTS@#The patients with comorbid hypertension in depression demonstrated lower CBF in bilateral superior frontal gyri, middle frontal gyri, inferior frontal gyri, right superior parietal gyrus, right inferior parietal gyrus, right supramarginal gyrus, left caudate nucleus and left insula lobe in comparison with the controls. Compared with control group, CBF values decreased in bilateral frontal lobes, but did not reach statistical significance. There were no significant differences of CBF values between the patients with hypertension and control subjects. Compared with depression, the patients with comorbid hypertension in depression showed lower CBF values in bilateral frontal lobes and right supramarginal gyrus. Compared with hypertension, lower CBF values in left middle frontal gyrus in the patients with comorbid hypertension in depression were shown. Correlation analysis indicated that no correlation between CBF values and scores of HAMD-17 was shown.@*CONCLUSION@#Although there were no significant decreases of CBF values in patients with depression and hypertension, regional hypoperfusions were observed in patients with comorbid hypertension in depression. Hypertension might play a synergistic action on cerebral hypoperfusion in patients with comorbid hypertension in depression.

Value of Diffusion-weighted Imaging in Evaluating the Activity of Sacroiliitis in Ankylosing Spondylitis / 中国医学科学院学报

Objective To investigate the clinical value of diffusion-weighted imaging (DWI) for evaluating the activity of sacroiliitis in ankylosing spondylitis (AS).Methods Totally 73 AS patients were prospectively enrolled and divided into active group (n=43) and chronic group (n=30) according to Bath ankylosing spondylitis disease activity index (BASDAI) scores and laboratory findings. Conventional magnetic resonance imaging (MRI) and DWI were performed in all subjects. Apparent diffusion coefficient (ADC) values of subchondral lesions in sacroiliac joint were independently measured by two radiologists,and the relative ADC (rADC) values were calculated. ADC and rADC values were compared between active and chronic groups. The efficiencies of ADC and rADC values for differentiating the activity of sacroiliitis were analyzed. In addition,the correlation coefficients of ADC values,rADC values,and BASDAI scores were calculated.Results The ADC and rADC values in the active group were (0.667±0.122)×10 mm /s and (1.715±0.343)×10 mm /s,respectively,which were significantly higher than those of the chronic group [(0.492±0.0651)×10 mm /s and (1.289±0.209)×10 mm /s,respectively)] (P0.81. The correlation coefficients of ADC value and rADC value with BASDAI scores were 0.82 and 0.80,respectively (P<0.0001). The optimal cutoff values of ADC value and rADC value for differentiating AS activity were 0.545×10 mm /s and 1.467×10 mm /s,respectively,The specificity was 81.8% for both indicators,and the sensitivity was 92.0% and 88.0%,respectively.Conclusion DWI is helpful in the quantitative assessment of the activity of sacroiliitis in AS patients.

Preoperative Evaluation of the Grade and Stability of Osteochondritis Dissecans of the Knee by Magnetic Resonance Imaging / 中国医学科学院学报

Objective To assess the diagnostic performance of magnetic resonance imaging (MRI) in the grading of osteochondritis dissecans (OCD) of the knee.Methods Totally 47 patients with OCD of the knee confirmed by arthroscopy were retrospectively enrolled in this study.The OCD lesions were classified into four stages according to classification system of the International Cartilage Repair Society.Two radiologists analyzed all MRI findings independently,and the results were compared with those of arthroscopy.Sensitivity,specificity,and accuracy were calculated.Kappa value were calculated to quantify inter-observer agreement of the diagnostic OCD grade between two doctors by MRI.Specificity,sensitivity,and accuracy of MRI criteria indicating instability for detection of OCD instability were calculated.Results Of these 47 patients with 48 OCD lesions,stages Ⅰ,Ⅱ,Ⅲ,and Ⅲ lesions were detected in 4,8,16,and 20 patients,respectively.The specificity,sensitivity,and accuracy for the diagnosis of OCD stability were 75.0% (83.3%),88.9% (86.1%),and 85.4% (85.4%) for observer l (2),and the agreement of OCD grade between these two readers was substantial with a Kappa value of 0.82.The specificity,sensitivity,and accuracy of MRI criteria for the detection of OCD instability including high T2 signal intensity at the interface between the OCD and the underlying bone,multiple cysts or a single cyst of>5 mm in diameter surrounding OCD lesions,high T2 signal intensity cartilage fracture line traversing the articular cartilage,and osteochondral defect were 83.3%,80.6%,and 81.3%;75.0%,72.2%,and 72.9%;66.7%,69.4%,and 68.8%;100%,86.1%,and 89.6%,respectively. Conclusions Osteochondral defect is the most specific MRI sign for diagnosing instable OCD of the knee,whereas osteochondral fracture line has the lowest accuracy.MRI is a useful method to evaluate the grade and stability of OCD of the knee.

Significance of Diffusion Tensor Imaging of Vastus Medialis Oblique in Recurrent Patellar Dislocation / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Numerous studies have investigated the influence of osseous factors on patellofemoral joint instability, but research on the influence of dynamic muscle factors in vivo is still in the exploratory stage. This study aimed to use magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) to evaluate vastus medialis oblique (VMO) fiber bundles in patients with recurrent patellar dislocation to explore the changes in muscle morphology and function.</p><p><b>METHODS</b>This prospective study involved 30 patients (7 males and 23 females; average age, 21.4 ± 3.8 years) clinically diagnosed with recurrent patellar dislocation in Peking University Third Hospital and 30 healthy volunteers matched for age, sex, and body mass index in our medical school between January 2014 and October 2014. None of the patients had a recent history of traumatic patellar dislocation or transient patellar dislocation. All patients underwent conventional MRI and DTI of the knee. The cross-sectional area of the VMO on MRI and the fractional anisotropy (FA), apparent diffusion coefficient (ADC), and primary (λ1), secondary (λ2), and three-level characteristic (λ3) values on DTI were measured. The independent-samples t-test was used to compare these parameters between the two groups.</p><p><b>RESULTS</b>Compared with the control group, the patient group showed significantly higher FA values (0.39 ± 0.05 vs. 0.33 ± 0.03) and significantly lower ADC (1.51 ± 0.13 vs. 1.58 ± 0.07), λ2 (4.96 ± 0.13 vs. 5.04 ± 0.07), and λ3 values (4.44 ± 0.14 vs. 4.58 ± 0.07; t = 5.99, t = -2.58, t = -3.02, and t = -4.88, respectively; all P < 0.05). Cross-sectional VMO area and λ1 values did not differ between the two groups (t = -1.82 and t = 0.22, respectively; both P > 0.05).</p><p><b>CONCLUSIONS</b>The functional status of the VMO is closely associated with recurrent patellar dislocation. MRI, especially DTI (FA, ADC, λ2, and λ3), can detect early changes in VMO function and might facilitate the noninvasive monitoring of the functional status of the VMO in patients with recurrent patellar dislocation.</p>

Value of multiple b-value diffusion-weighted imaging for differentiation of benign and malignant pulmonary masses / 中国医学科学院学报

<p><b>OBJECTIVE</b>To explore the value of multiple b-value diffusion-weighted imaging (DWI) for differentiation of benign and malignant pulmonary masses.</p><p><b>METHODS</b>Thirty-eight patients were examined by routine sequences and DWI pulse sequence. DWI was acquired through a single-shot echo-planar imaging combined with a respiratory-triggered mode and parallel acquisition. Nine b values ranging from 0 to 1500 s/mm(2) (0, 50, 100, 150, 200, 400, 600, 1000, 1500 s/mm(2)) were used. The intravoxel incoherent motion model was applied to estimate pure diffusion coefficient D, perfusion-related diffusion coefficient D(*), and perfusion fraction f. Mann-Whitney U test was used to compare all measured parameters between benign and malignant groups. The diagnostic performance of the related parameters was evaluated with receiver operating characteristics (ROC) analysis.</p><p><b>RESULTS</b>Of these 38 patients, 30 were pathologically confirmed and 8 were diagnosed based on clinical data. There were 23 lung malignant masses and 15 benign lesions. A significant reduction of D was found in malignant group than in benign group (Z=3.308, P=0.001), while no significant differences in D(*)(Z=1.646, P=0.100) and f(Z=1.254, P=0.210) were observed between the two groups. The area under the ROC curve for D value (0.839) was largest. When the cutoff value was selected as 0.90×10(-3) mm(2)/s, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of diagnosing malignant masses were 95.7%, 80.0%, 90.9%, 91.7%, and 88.9%,respectively.</p><p><b>CONCLUSION</b>The D value in multiple b-value DWI has certain significance in differentiating the benign and malignant pulmonary masses and has the best diagnostic efficiency.</p>

Effect of digital radiography processing parameters on digital chest radiograph for occupational exposed workers / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the effect of different processing parameters of digital radiography (DR) on the image quality of digital chest radiograph in dust-exposed workers.</p><p><b>METHODS</b>One hundred and five dust-exposed workers underwent both high-KV radiography and DR to obtain chest radiographs; the image processing parameters were set by the conventional processing method for digital chest radiograph (method A) and the processing method based on the special requirements of occupational diseases (method B). With the high-KV chest radiograph as the reference, the image qualities at 10 anatomic sites of DR image were graded. The images acquired by DR and high-KV radiography were compared, and the DR images acquired by methods A and B were also compared.</p><p><b>RESULTS</b>For method A, the scores at the 10 anatomic sites of DR image were mostly 0 and +1, accounting for over 88%, and the mean score was 0.23 ∼ 0.65, there was a significant difference between the mean score of DR image and the score of high-KV image (P < 0.001). For method B, the scores at the 10 anatomic sites of DR image were mostly 0, accounting for over 65%, and the mean score was -0.01∼ +0.02 except at the pleura and chest wall; there was no significant difference between the mean score of DR image and the score of high-KV image (P > 0.05). There were significant differences in the scores at the 10 anatomic sites between the DR images acquired by methods A and B (P < 0.01).</p><p><b>CONCLUSION</b>The DR images acquired based on different processing parameters are different. The quality of DR image acquired by the processing method based on the special requirements of occupational diseases is similar to that of high-KV image at the anatomic sites.</p>

Effect of tube voltage on digital chest radiograph for phantom and occupational exposed workers / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the image quality of different tube voltage on digital chest radiograph for contrast detail phantom (CDRAD2.0) and occupational exposed workers.</p><p><b>METHODS</b>The CDRAD2.0 phantom DR images of high KV and different tube voltages were analyzed by 3 readers, image quality figure (IQF) were calculated and compared; at the same time 136 exposed workers were examined with high-kV and DR chest radiograph of different tube voltages. Contrast to high-KV images, 10 anatomic sites were scored .The image differences were compared between DR and high-kV.</p><p><b>RESULTS</b>On CDRAD2.0 phantom, the IQF value of DR images in 3 readers were minimum in the condition of 120 kV, average value was 22.25. The analysis of variance in model with random effects, the mean IQF value of different tube voltage DR image had a significant difference (F = 13.775, P<0.01); By Dunnett t-tests analysis, the mean IQF value of DR image in 120 kV and high kilovoltage had no difference (t = -0.58, P = 0.979); On clinical cases, the DR image of 120 kV showed the closest anatomy to the high KV, the mean had no significant difference with 0 (P > 0.05) with single sample t test.</p><p><b>CONCLUSION</b>On the CDRAD2.0 phantom or clinical exposed workers, the DR image quality of 120 kV tube voltage equals to high-KV basically.</p>

CT-guided percutaneous radiofrequency ablation of spinal osteoid osteoma / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>This study evaluated the feasibility, efficacy and safety of CT-guided percutaneous radiofrequency ablation in patients with spinal osteoid osteoma.</p><p><b>METHODS</b>Two patients suffered spinal osteoid osteoma were treated with CT-guided percutaneous radiofrequency ablation under local anesthesia. Lesions located in sacral vertebrae and cervical vertebrae, which were adjacent to nerve root and spinal canal respectively. Tumors were treated under 90°C radiofrequency temperature lasting 4 minutes by an electrode placement. Visual analog scale was used to evaluate the pain improvement.</p><p><b>RESULTS</b>No complications were observed pre- and post-operation. Patients recovered to normal activities immediately and achieved complete pain relief in 24 hours. No symptoms were recurrent in 5 months and 4 months follow up. Mild scoliosis has been recovered in case 2.</p><p><b>CONCLUSIONS</b>CT-guided percutaneous radiofrequency ablation of spinal osteoid osteoma is safe, effective and has more clinical benefits. The long-term outcome needs further observation.</p>

CT guided ~(125)Ⅰseed brachytherapy for recurrent rectum cancer / 中华放射肿瘤学杂志

Objective To investigate the technological feasibility,efficacy and morbidity of cr guided ~(125)Ⅰseed implantation for recurrent rectum cancer.Methods Twenty-three patients with recurrent rectum cancer were treated with cr guided interstitial ~(125)Ⅰseed brachytherapy.In 20 patients the procedure was performed under epidural anesthesia and 3 patients under local anesthesia.Treatment planning system was used to calculate the number of seeds,the space distribution and the introduction of the seeding needles.Matched peripheral dose (MPD) of ~(125)Ⅰseed implantation ranged from 90-120 Gy for patients who had had external radiotherapy,and 140- 160Gy for those who had not.The planning target volume(PTV)was clinical target volume(CTV)plus 1 cm margin.The range of radioactivity of the ~(125)Ⅰseeds was 18.5-25.9 MBq.All these 23 patients had CT scan at 5 mm intervals after implantation for quality evaluation,together with routine chest,pelvic X-ray films within 24-48 hours after seed implantation.Three patients received three-dimensioual conformal radiation therapy(3DCRT) to a total dose of45-50 Gy,with 2-3 Gy/f.Follow-up time was from 3 to 28 months.Results All patients was able to tolerate seed implantation well.Complete pain relief was observed in 12/15,and partial relief in 2/15 and no response in 1/15,with a response rate of 93%.The local control rate was 87%.The 1-and 2-year survival rate was 93% and 50% respectively.Two of four patients have died of dissemination to the lung after 8 and 12 months. One seed has migrated into the pelvis without causing any untoward morbidity.Conclusion CT guided ~(125)Ⅰseed implantation for recurrent rectum cancer is safe,minimally invasive,causing only mild morbidity.It possesses a high efficacy,yet it should be given in combination with external beam radiation and chemotherapy,should distant metastasis be observed.