Summary： To evaluate lesion detection of MRI in knee joint osteoarthritis in patients with symptoms of pain, the correlation between MRI findings and varying degrees of reported pain was assessed. Twenty-eight patients （31 knees） with osteoarthritis were recruited for this study. The degree of knee pain was assessed by VRS scores. The knees were evaluated by plain film radiograph utilizing Kellgren-Lawrence scores. Multiple MR sequences were performed on a 1.5T MR-system, including sagittal and coronal dual fast spin echo （TRITE 3660/11/120 ms, slice thickness 5 mm）, coronal spin echo T1-weighted （TR/TE 360/9 ms, slice thickness 5 mm）, sagittal fat saturated 3D-spoiled gradient-recalled echo （TR/TE 50/6 ms; slice thickness 1.5 mm; flip angle 40°）, and 3D steady-state free precession （TR/TE 6/2.2 ms; slice thickness 1.6 mm; flip angle 30°） pulse sequences for the purpose of detecting abnormities of cartilage, menisci, the anterior cruciate ligaments, bone marrow edema-like lesions, osteophytes, synovitis, and joint effusions. MR findings were compared with the degree of pain using Fisher exact test with P values less than 0.05 indicating a statistically significant difference. The results showed that, of the 31 knees evaluated, mild pain was reported in 11 and severe pain in the remainder. Kellgren-Lawrence scores of all 31 evaluated OA knees were as follows： grade 1 lesions （n=6）, grade 2 lesions （n=14）, grade 3 lesions （n=8）, and grade 4 lesions （n=3）. Articular cartilaginous defects were found in 37.1% of knees. Abnormalities of the menisci and anterior cruciate ligaments, bone marrow edema-like lesions, osteophytes, synovitis, and joint effusions were detected in 32.3%, 38.7%, 45.2%, 100%, 15.1% and 67.7% of knees, respectively. Of these variables, only the differences in prevalence of joint effusions were significantly different in the mild and severe pain groups （P=0.004）. It is concluded that MRI evaluates the entire joint structure of the osteoarthritic knee, d
Background There is a strong need for quick noninvasive diagnostic technique that can give a valid estimate of the status of the cartilage reliably, discriminating intact cartilage from various grades of impaired cartilage. The goal of this study was to assess the incidence of knee cartilage injuries and compare the accuracy of two-dimension spin echo （2D SE） and fast spin echo （FSE） （conventional MRI）, three-dimensional spoiled gradient echo （3D SPGR）, three-dimensional fast imaging employing steady state acquisition （3D FIESTA） MR imaging sequences with surgical examination of the articular cartilage. Methods One hundred and thirty-eight knees with history of knee trauma received conventional MRI, 3D SPGR and 3D FIESTA MRI examination before surgery, and surgical examination of articular cartilage was used as reference standard. A modified version of the Noyes classification system was applied for the evaluation of the lateral femoral condyle （LFC）, medial femoral condyle （MFC）, lateral tibial plateau （LTP）, medial tibial plateau （MTP）, trochlea and patella. The incidence and distributions of different injured grades at different articular surfaces of knee were assessed. A series of assessment indeces of 3D SPGR, 3D FIESTA, and the combination of the conventional MRI and 3D SPGR imaging were calculated. Results The incidence of cartilage defects （grade 2 to 4） was 22% （183/828）, according to surgical examination. Grade 3 and 4 lesions were absent at the medial tibial plateau. The rates of exact match between the grading results of different MRI procedures and surgical examination were 49% of 3D SPGR, 61% of 3D FIESTA, and 82% of the combination of 3D SPGR and conventional MRI. Also, the combination of 3D SPGR and conventional MR imaging provided the highest sensitivity, specificity, accuracy, positive and negative predictive values, at 71%, 97%, 90%, 90% and 90%, respectively. Conclusions For all the articular surfaces of the traumatic knees, about one fifth （22%）
LI Xiao-mingPENG Wen-jiaWU HuaKacher DanielXIA Li-mingAI FeiLI FengXIONG Wei
Background With the advanced MRI techniques, pathologic features can be detected at an early stage and quantitatively evaluated, resulting in the advantages of early diagnosis and prompt treatment. This study aimed to determine the value of diffusion-weighted MR imaging （DWI） in detection of early ankylosing spondylitis （AS） and investigate the characteristic manifestations of AS on whole body DWl （WB-DWl）. Methods Twenty patients with the diagnosis of early AS, twenty patients with low back pain （LBP）, and twenty-five healthy volunteers were included in this study. The subchondral bone apparent diffusion coefficients （ADC） among these groups in the bilateral ilia and sacrum along the sacroiliac joints were compared. An independent sample t-test was utilized to analyze ADC value differences among groups. P-values less than 0.05 denoted statistical significance. The mean ADC values of focal DWl lesions in AS patients were also measured. Whole body diffusion-weighted imaging was performed in fifteen additional AS patients, and analyzed with MIP and MPR techniques in comparison to conventional MR images in order to evaluate the ability to detect AS lesions with whole body DWI. Results Mean ADC values in AS patients were （0.518±0.122）×10^-3 mm2/s in the ilium and （0.503＋0.168）x103 mm2/s in the sacrum. These were significantly greater than the values measured in the ilium and sacrum of LBP patients, （0.328±0.053）×10^-3 mm2/s in the ilium and （0.311±0.081）×10^-3 m2/s in the sacrum, and control group, （0.325±0.015）×10-3 mm2/s in the ilium and （0.318±0.011）×10^-3 mm2/s in the sacrum respectively. No statistically significant differences were found between LBP group and control group. The mean ADC value of focal DWI lesions in early AS patients was （0. 899±0.265）×10^-3 mm2/s, which was significantly higher than that of adjacent normal-appearance areas （（0.454±0.079）×10^-3 mm2/s）. WB-DWl detected abnormalities in the 15 additional AS patients both with
