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OBJECTIVE:To investigate changes in bone metabolism by positron emission tomography (PET), as well as spatial relationships between bone metabolism and magnetic resonance imaging (MRI) quantitative markers of early cartilage degradation, in anterior cruciate ligament (ACL)-reconstructed knees. DESIGN:Both knees of 15 participants with unilateral reconstructed ACL tears and unaffected contralateral knees were scanned using a simultaneous 3.0T PET-MRI system following injection of 18F-sodium fluoride (18F-NaF). The maximum pixel standardized uptake value (SUVmax) in the subchondral bone and the average T2 relaxation time in cartilage were measured in each knee in eight knee compartments. We tested differences in SUVmax and cartilage T2 relaxation times between the ACL-injured knee and the contralateral control knee as well as spatial relationships between these bone and cartilage changes. RESULTS:Significantly increased subchondral bone 18F-NaF SUVmax and cartilage T2 times were observed in the ACL-reconstructed knees (median [inter-quartile-range (IQR)]: 5.0 [5.8], 36.8 [3.6] ms) compared to the contralateral knees (median [IQR]: 1.9 [1.4], 34.4 [3.8] ms). A spatial relationship between the two markers was also seen. Using the contralateral knee as a control, we observed a significant correlation of r=0.59 between the difference in subchondral bone SUVmax (between injured and contralateral knees) and the adjacent cartilage T2 (between the two knees) [P&nbsp

Background: Global Minimum Essential Requirements (GMER) indicated critical thinking is an essential competency a medical graduate should possess. This study was to investigate the disposition for critical thinking that Chinese medical students possess and to explore the impact of current trends in medical education on the cultivation of these students’ critical thinking capabilities. Methods: We used Multistage Stratified Cluster Sampling to recruit a total of 1241 medical students, in five different years of training, from three different classes of the medical schools in China (Tongji, Shanghai; Soochow, Jiangsu; and Gannan, Jiangxi). The Critical Thinking Disposition Inventory-Chinese Version (CTDI-CV) was used to collect cross-sectional data. One hundred and twelve students underwent a scrutinized longitudinal study between their third and fourth years. Findings: The mean CTDI-CV score of the total population of 1241 was 287.04.729 (58.7%) received a 280 or higher. Statistically significant differences were found between schools, years of school attended, GPA, time spent learning after class, medical students’ attitude toward medicine, desire to be a doctor after graduation, and perception of critical thinking. Chinese students scored the highest on “Inquisitiveness” and the lowest on “Truth seeking” for CTDI-CV subscale. The 112 students in the longitudinal study had significantly lower CT subscale scores and percentage possesses positive CT disposition (>280) after one academic year. Interpretation: Even though Chinese medical students demonstrate a positive disposition for critical thinking in general, the Chinese system of medical education may not do enough to stimulate critical thinking skills in the students it cultivates. There exists a gap between current critical thinking abilities and the standard for which they should strive for. Chinese medical schools should institute reforms to their traditional curricula, teaching methods, and evaluation systems, as a means to bridge this gap and further develop critical thinking abilities within their medical students.

PurposeTo evaluate positron emission tomography / magnetic resonance imaging (PET/MRI) knee imaging to detect and characterize osseous metabolic abnormalities and correlate PET radiotracer uptake with osseous abnormalities and cartilage degeneration observed on MRI.Materials and methodsBoth knees of 22 subjects with knee pain or injury were scanned at one timepoint, without gadolinium, on a hybrid 3.0T PET-MRI system following injection of 18 F-fluoride or 18 F-fluorodeoxyglucose (FDG). A musculoskeletal radiologist identified volumes of interest (VOIs) around bone abnormalities on MR images and scored bone marrow lesions (BMLs) and osteophytes using a MOAKS scoring system. Cartilage appearance adjacent to bone abnormalities was graded with MRI-modified Outerbridge classifications. On PET standardized uptake values (SUV) maps, VOIs with SUV greater than 5 times the SUV in normal-appearing bone were identified as high-uptake VOI (VOIHigh ). Differences in 18 F-fluoride uptake between bone abnormalities, BML, and osteophyte grades and adjacent cartilage grades on MRI were identified using Mann-Whitney U-tests.ResultsSUVmax in all subchondral bone lesions (BML, osteophytes, sclerosis) was significantly higher than that of normal-appearing bone on MRI (P < 0.001 for all). Of the 172 high-uptake regions on 18 F-fluoride PET, 63 (37%) corresponded to normal-appearing subchondral bone on MRI. Furthermore, many small grade 1 osteophytes (40 of 82 [49%]), often described as the earliest signs of osteoarthritis (OA), did not show high uptake. Lastly, PET SUVmax in subchondral bone adjacent to grade 0 cartilage was significantly lower compared to that of grades 1-2 (P < 0.05) and grades 3-4 cartilage (P < 0.001).ConclusionPET/MRI can simultaneously assess multiple early metabolic and morphologic markers of knee OA across multiple tissues in the joint. Our findings suggest that PET/MR may detect metabolic abnormalities in subchondral bone, which appear normal on MRI.Level of evidence2 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;45:1736-1745.