Objective To evaluate the correlation between MRI and X-Ray discography findings and pain response at provocative discography in patients with discogenic back pain. Methods Two hundred and fifty-six lumbar intervertebral discs in 93 patients who underwent MRI and X-Ray discography were included in this study. MR images were retrospectively evaluated regarding disc degeneration, endplate abnormalities and high intensity zone. Disc degeneration was graded according to the modified criteria of Pearce, et el. Evaluation of disc morphology was performed with X-Ray discography by using the classification of Adams, et al. Endplates and adjacent bone marrow abnormalities were classified according to Modic,et al. During discography concordant pain was regarded as positive, whereas discordant pain and no pain were regarded as negative. The data were analyzed using the Chi-squnre test. Results There were 116 discs with concordant pain and 140 discs with discordant pain or no pain. Of 256 discs on discography, 17 discs were type Ⅰ17(6.6%),type Ⅱ were 25(9.8%),type Ⅲ were 91(35.5%), type Ⅳ were 77(30.1%) and type Ⅴ were 46(18.0% ). On MR images, discs of grade Ⅰ were 23 (9.0%) ,grade Ⅱ were 34(13.3%), grade Ⅲ were 84(32.8%), grade Ⅳ were 85 (33.2%) and grade Ⅴ were 30(11.7%). There was positive correlation between Pearce graded of MRI and classification of Adams of discography (r=0.62, X2 =160.87,P <0.01).In 123 discs of type Ⅳ to type Ⅴ on discography, 104 discs were with concordant pain. There was positive correlation between type Ⅳ-Ⅴ and concordant pain( r=0.60, X2 = 144.08, P < 0.01). In 115 discs of Ⅳ-Ⅴ grade degeneration, 99 discs presented with concordant pain. There was positive correlation between Ⅳ-Ⅴ grade disc degeneration and concordant作者单位:510120 广州,中山大学附属第二医院放射科 pain(r = 0.59, X2 = 137.11, P <0.01 ). In 60 discs with high intensity zone(HIZ), 52 discs presented with concordant pain. There was positive correlation between HIZ and concordant pain ( r=0.41, X2= 51.93, P <0.01 ). In 58 discs with endplate degeneration, 51 presented with concordant pain. There was positive correlation between Modic degeneration and concordant pain ( r = 0.41, X2= 52.76, P < 0.01 ). Conclusion In patients with chronic low back pain, MR imaging may present moderate to severe disc degeneration, high intensity zone, endplates and adjacent bone marrow abnormalities. MR findings with concordant pain can raise the diagnostic possibility of discogenic lumbar pain. Typical discography findings, fissured or ruptured disc, with concordant pain are important diagnostic evidence for discogenic lumbar pain.

Objective To prospectively evaluate the value of diffusion-weighted imaging with background signal suppression (DWIBS) in the detection and diagnoses of metastatic cervical lymph nodes. Methods Twenty patients with head and neck squamous cell carcinomas underwent conventional MRI and DWIBS. The ADC values were measured and compared between metastatic and benign lymph nodes. The abilities of DWIBS and conventional MRI in the evaluation of metastatic cervical lymph nodes were compared. Results Conventional MRI demonstrated 101 lymph nodes, in which 58 were diagnosed as metastatic nodes. When MRI criteria were used for discrimination between metastatic and benign nodes, the obtained sensitivity, specificity, accuracy, positive and negative predictive value were 78% (47/60), 81%(44/54), 80% (91/114), 82% (47/57) and 77% (44/57), respectively. The mean ADC values of metastatic nodes (n =60) and benign nodes (n =54) were (0.945 ±0.122) × 10-3 mm2/s and (1. 210 ±0. 151 ) × 10-3 mm2/s ( t = - 10. 354 ,P ＜0. 01 ). When an ADC value of 1. 090 × 10 -3 mm2/s was used as the threshold for discrimination between metastatic and benign nodes, the obtained sensitivity, specificity,accuracy, positive and negative predictive value were 88% (53/60), 80% (43/54), 84% (96/114), 83%(53/64) and 86% (43/50), respectively. Conclusion DWIBS is helpful in diagnosing metastatic cervical lymph nodes of head and neck squamous cell carcinoma, and is superior to conventional MRI in their detection.

Objective To discuss the value of MR T2 mapping in the research of the biomechanics and function of cartilage of knee joint.Methods Knees of 20 healthy adults before and after jogging and 19 osteoarthritis patients were examined with sagittal 8-echo SE sequence.The T2 value of cartilage was selected and calculated.The T2 values in the superficial and deep cartilage of femoral and tibial joint before and after jogging were compared,so did between the osteoarthritis patients and healthy adults.The source images were sent to the workstation to get T2 mappings.The T2 value of cartilage between before and after jogging was compared with paired-samples t test.The T2 value between superficial and deep cartilage before jogging was compared with independent-samples t test,so did between the osteoarthritis patients and healthy adults.Results The T2 values in the superficial and the deep tibial cartilage were(48.8±6.3)ms,(44.3±5.7)ms before jogging and(43.4±5.0)ms,(40.3±6.1)ms after jogging.The T2 values were significantly different between before and after jogging(t=6.004 and t=5.037,P＜0.05).There was a significant difference between superficial and deep tibial cartilage before jogging(t=3.148,P＜0.01).The T2 Values in the superficial and deep femoral cartilage were(52.1±5.7)ms,(47.7±5.3)ms before jogging and(47.2±4.5)ms,(43.6±4.1)ms after jogging.The T2 values were significantly different between before and after jogging(t=6.169 and t=5.957,P＜0.05).There was a significant difference between superficial and deep femoral cartilage before jogging(t=3.384,P＜0.01).The T2 mapping showed those changes.The mean T2 value in the tibial cartilage of osteoarthritis patients was(56.0±9.1)ms and was higher than that of healthy adults.There was a significent difference between osteoarthritis patients and healthy adults(t=-3.446,P＜0.01).Conclusion T2 mapping can be used in the research of biomechanics and function of cartilage and has a prelimilary value in the diagnosis of cartilage degeneration.

Objective To investigate the clinical value of three dimensional dynamic contrast enhanced MRA(3D DCE MRA)on esophageal and gastric varices compared with endoscopy.Methods From April 2003 to June 2008,153 patients with portal hypertension who underwent both 3D DCE MRA and endoscopy were reviewed retrospectively.All the patients were divided into bleeding group and non-bleeding group according to the clinical symptoms.The location and degree of the esophagogastric varices on 3D DCE MRA were assessed with postprocessing images,including subtraction,MIP and thin-slab maximum intensity projection(thin-MIP),and were compared with the results of endoscopy.The maximum,minimum and mean diameters of esophagogastric varices inside and outside of the wall were measured on the reformed images.The correlation between the findings of 3D DCE MRA and endoscopy were analyzed with Spearman rank correlation coefficient test The rates of esophagogastric varices outside of the wall in bleeding and non-bleeding group were compared by means of Chi-square test Results In bleeding group,severe esophageal varices were documented in 59 patients,moderate in 6 patients,mild in 5 patients;in non-bleeding group,severe esophageal varices were documented in 32 patients,moderate in 4 patients,mild in 5 patients.Severe,moderate,and mild gastric varices were documented in 28,34 and 16 in bleeding group,while they were 7,12 and 9 in non-bleeding group.Esophageal and gastric varices can be wholly presented on MIP images after subtraction,while the esophagogastric varices inside and outside of the wall can be differentiated on thin-MIP images.The location and degree of esophagogastric varices on 3D DCE MRA were correlated with the findings of the endoscopy.The range of r was from 0.544 to 0.878(P＜0.01).In 91 patients with severe esophageal varices,27 patients presented outside esophageal varices in bleeding group(n=59)and 24 patients presented outside esophageal varices in non-bleeding group(n=32).There was a significant difference in ratio of outside esophageal varices between bleeding group and nonbleeding group(X~2=7.199,P＜0.01).In 35 patients with severe gastric varices,22 patients showed adventitial gastric varices in bleeding group(n=28)and 4 patients showed adventitial gastric varices in non-bleeding group(n=7).The ratio of adventitial gastric varices in bleeding group was not significantly different from that of non-bleeding group(P=0.340).Conclusions 3D DCE MRA can display and differentiate the esophagogastric varices both inside and outside of the wall by three dimensional reconstruction.The results of 3D DCE MRA and endoscopy have good correlation.It is of importance in evaluating the esophageal varices outside of the wall,because they may indicate decreased risk of haemorrhage in patients with severe degree of esophageal varices.

Objective To evaluate the apparent diffusion coefficient (ADC) of parenehyma and necrosis in distinguishing among metastatic lymph nodes, lymphoma and tuberculous lymph nodes. Methods Thirty-six patients with cervical lymph nodes metastasis from the head and neck squamous cell carcinomas,19 patients with lymphoma and 23 patients with lymph nodes tuberculosis underwent diffusion-weighted imaging. The ADC values were measured and compared in parenchyma and necrosis of 177 lymph nodes confirmed by histopathology (n = 114) and clinical follow-up (n = 63). The means between two groups were compared by t-test, and one-way analysis of variance (one-way ANOVA) was used to analyze the data among three or more groups. Results The mean ADC values of parenchyma in metastatic nodes, lymphoma and tuberculous nodes were (0.93±0.16) × 10-3mm2/s, (0.64±0.13) × 10-3mm2/s and (1.01±0.11) ×10 -3 mm2/s respectively (F = 82.928, P < 0.01) ; the ADC values of necrosis in metastatic and tuberculous nodes were (2.02 ± 0. 36) × 10-3 mm2/s and (1.25 ± 0.15) × 10-3 mm2/s respectively (t = 12.045, P <0.01). An ADC value of parenchyma lower than or equal to 0.77 × 10 -3mm2/s was used as the threshold for lymphoma, with a sensitivity 83% and specificity of 89%. An ADC value of necrotic area greater than or equal to 1.60 × 103mm2/s was used as the threshold for metastatic nodes, with a sensitivity of 88% and specificity of 100%. Conclusion The ADC value of lymph nodes, especially for their internal necrotic areas, can help judge the nature of the cervical lymph nodes.

Objective The purpose of our study was to investigate three dimensional dynamic contrast enhanced MR angiography(3D DCE M RA) in the detection of portosystemic collateral circulation in the falciform ligament in patients with portal hypertension. Methods From April 2003 to July 2008, 53 portal hypertension patients with varices in the falciform ligament were evaluated with 3D DCE MRA.Two radiologists independently assessed the number, diameter, location and drainages of the portosystemic collateral circulation in the falciform ligament according to the information on the 3D DCE MRA.Results The veins in the falciform ligament were classified into the superior and inferior groups, and both groups arise from the left trunk of the portal vein.In our study, the number of varices detected on 3D DCE MRA images varied from 1 to 3, and the diameters of these vessels varied from 0.4 to 2.6 cm.The inferior group consisted of paraumbilical/umbilical veins (47 cases), which flowed toward umbilicus and then drained upwards (n = 16) including deep superior epigastric veins (n = 7), superficial superior epigastric veins (n = 9), downwards (n = 40) including deep inferior epigastric veins (n = 7), superficial inferior epigastric veins (n = 33), or upwards and downwards at the same time (n = 9).The superior group of vessels in the falciform ligament were directly anastomosed with the internal thoracic vessels (n = 6).Conclusion In patients with portal hypertension, 3D DCE MRA can optimally demonstrate the portosystemic collateral circulation in the falciform ligament, which includes the superior and inferior drainage groups.

Objective To analysis the effect of axial loading to ADC value, FA of lumbar intervetebral discs. Methods Forty five patients with low back pain (age range, 25 to 54 years) were evaluated with MR T2WI, MR T1WI and diffusion tensor imaging (DTI) of the lumbar spine. Following axial loading with 40% to 50% body weight for 10 minutes, a repeat DTI was performed. DTI were obtained by using an echo-planar imaging ( EPI ) sequence, TE 89 ms, TR 2500 ms, b value of 400 s/mm2,6 noncollinear diffusion directions. Scan time was approximately 4 min 10 s. An isotropic ADC map, FA map and bo map were calculated from DTI sequence. The mean ADC value, FA prior to and following axialloading were analyzed with t test and Rank Sum test. Results Forty five patients with 225 discs were evaluated and 223 discs were included in the study except for 2 calcified discs. The Pfirrmann grading results were as following: 100 Grade Ⅱ , 48 Grade Ⅲ, 59 Grade Ⅳ, and 16 Grade Ⅴ. No significant difference existed in the mean ADC value before [ ( 1666 ± 252 ) × 10-3 mm2/s ] and after [ ( 1662 ± 253 ) ×10 -3 mm2/s ] axial loading ( Z = - 1.363, P ＞ 0.05 ), but the mean FA [ ( 301 ± 104 ) × 10 -3, ( 316 ±112) × 10-3 ] value increased ( Z = - 2.794, P ＜ 0.05 ). The paired-samples t test show that the mean ADC value [ ( 1685 ± 190) × 10-3 mm2/s, ( 1624 ± 180) × 10-3mm2/s] of Grade Ⅲ discs decreased after axial loading, t=3.513, P＜0. 05, Grade Ⅲ, Ⅳdiscs mean FA value [(300±87) ×10-3, (326±87) ×10-3 for Grade Ⅲ and (348 ±67) × 10-3, (351 ± 71 ) × 10-3 for Grade Ⅳ ] increased, t = - 2. 210,- 2.006, P ＜ 0.05. No significant difference existed in Grade Ⅱ , Ⅳ and Ⅴ discs ADC value, all the P ＞0.05. No significant difference existed in Grade Ⅱ and Ⅴ discs FA value, both the P ＞ 0.05. Conclusions Short time axial loading mainly affect the mildly degenerated discs, the ADC value decreases and the disc diffusion ability decreases. No obvious change in ADC value or disc diffusion ability existed in the normal and severely degenerated discs.

BACKGROUND: Children and adolescents are in the growth and development stage, so the use of the same reconstruction methods as adults is easy to induce complications including limb length differences, high graft failure rate and re-surgical intervention. Simultaneously, the occurrence of osteoarthritis will also be advanced. OBJECTIVE: To explore the anatomical characteristics of the anterior cruciate ligament between children, adolescents and adults on MRI, and to provide an anatomical basis for the reconstruction of the anterior cruciate ligament in children and adolescents. METHODS: A retrospective analysis of patients undergoing knee MRI examination in Qingdao Municipal Hospital from October 2016 to October 2018 was conducted. These patients were divided into child and adolescent group and adult group (n=48 per group). The angle between the anterior cruciate ligament and the tibia and femur on the sagittal plane and the position of the anterior cruciate ligament tibial insertion, the angle between the anterior cruciate ligament and the tibia on the coronal plane, the tibial insertion of the anterior cruciate ligament and femur, and the position of the femur stop point on the axial position were measured in both groups. The data obtained from the measurement of the anterior cruciate ligament of children and adolescents were processed. The growth curves of the shape and position of the anterior cruciate ligament of children and adolescents were drawn, and the law of its growth changes was analyzed. RESULTS AND CONCLUSION: (1) The angle between the sagittal plane of the anterior cruciate ligament and the femur (t=﹣2.906, P<0.05), the angle between the sagittal plane of the anterior cruciate ligament and the tibia (t=﹣10.280, P < 0.05), the anterior cruciate ligament angle between the coronal plane and the tibia (t=﹣5.714, P<0.05) were smaller in the child and adolescent group than those of the adult group, and the difference was significant. (2) The ratio of the tibia coronal plane of the anterior cruciate ligament (t=﹣7.263, P < 0.05) and the ratio of the anterior cruciate ligament and femur axial plane (t=﹣7.378, P < 0.05) were lower in the child and adolescent group than those of the adult group, and the difference was significant. (3) There was no significant difference in the anterior cruciate ligament and tibia sagittal plane ratio (t=﹣1.588, P>0.05) and anterior cruciate ligament and femoral coronal surface ratio (t=﹣1.647, P>0.05) between the child and adolescent group and the adult group. (4) The growth curve results showed that during the growth and development, the angle between the anterior cruciate ligament and the femur and tibia on the sagittal plane and the angle with the tibia on the coronal plane changed from small to large (P<0.05). The relative position of the tibial insertion in the coronal position changed from small to large, which indicates that during the growth and development, the tibial insertion moved from inside to outside relative to the inside of the tibial plateau on the coronal plane (P < 0.05). (5) The relative position of femoral insertion in the axial position changed from small to large, suggesting that during the growth and development, the femoral insertion moved from the outside to the inside relative to the lateral femoral condyle (P<0.05). (6) There was no significant difference in the tibial insertion and the femoral insertion between the child and adolescent group and adult group (P>0.05).