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Objective: To demonstrate fluoroscopy dose reduction through both simulated injections on a phantom and patient injections.Materials and Methods: Our study was IRB-approved and HIPAA-compliant. Simulation on a phantom was used to estimate effective dose, entrance dose, and organ doses for hip joint injections without and with dose minimization technique (DMT). Additionally, 1,094 joint, bursae, and tendon sheath injections performed by three operators in the same fluoroscopy suite were evaluated both before and after application of DMT. Fluoroscopy time (FT), dose, and dose area product (DAP) of injections were compared using unpaired t-tests with P > 0.05 considered statistically significant.Results: For the phantom simulation comparing injections without DMT and with DMT, the total DAP was 191.7 vs 18.7 μGy·m2, and the entrance dose was 10.2 vs 3.6 mGy, respectively. For both men and women, DMT reduces effective dose and organ doses. For all injections, the FT (0.7 to 0.2 min), dose (5.6 to 1.9 mGy), and DAP (56.9 to 19.1 μGy·m2) for all three operators decreased with DMT and remained statistically significant when stratified by the two most common injections, glenohumeral and hip joint injections (P < 0.05).Conclusions: FT, effective dose, entrance dose, and DAP can be reduced with the use of simple easy-to-learn techniques, which will benefit both the patient and the radiologist. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the use of routine MR imaging sequences in detecting and characterizing secondary reactive synovitis of the knee joint using arthroscopy as the standard of reference.Design and Patients: Fifty consecutive patients with a history of knee pain who were referred for MR imaging and subsequently underwent arthroscopy of the knee comprised the study group. MR images were evaluated for the presence and appearance of synovitis reflected in synovial thickening and irregularity. Synovial thickening was graded on MR imaging as follows: 0=normal, 1=thin line of increased signal intensity, 2=increased signal intensity with frond-like or hair-like projections and a granular appearance of joint fluid. Standard knee imaging protocols were used.Results: The sensitivity, specificity, and accuracy of MR imaging in detecting synovitis compared with arthroscopy were 88%, 97%, and 95%, respectively. Grade 1 synovitis was best seen on proton-density-weighted images, demonstrating increased signal intensity of the synovium against the relatively low signal intensity of the joint fluid. Grade 2 synovitis was best seen on proton-density images and T2-weighted spin echo and fast spin echo images with fat saturation, demonstrating a granular and linear hair-like appearance of joint fluid. Axial and sagittal imaging planes were most helpful in the diagnosis of synovitis.Conclusion: Routine MR pulse sequences are useful in identifying the presence and extent of synovial abnormalities. The detection of different stages of synovial pathology should become an important part of the evaluation of the post-traumatic patient as treatment may be altered as a result. [ABSTRACT FROM AUTHOR]

In a population-based study, we found that computed tomography (CT)-based bone density and strength measures from the thoracic spine predicted new vertebral fracture as well as measures from the lumbar spine, suggesting that CT scans at either the thorax or abdominal regions are useful to assess vertebral fracture risk., Introduction: Prior studies have shown that computed tomography (CT)-based lumbar bone density and strength measurements predict incident vertebral fracture. This study investigated whether CT-based bone density and strength measurements from the thoracic spine predict incident vertebral fracture and compared the performance of thoracic and lumbar bone measurements to predict incident vertebral fracture., Methods: This case-control study of community-based men and women (age 74.6 ± 6.6) included 135 cases with incident vertebral fracture at any level and 266 age- and sex-matched controls. We used baseline CT scans to measure integral and trabecular volumetric bone mineral density (vBMD) and vertebral strength (via finite element analysis, FEA) at the T8 and L2 levels. Association between these measurements and vertebral fracture was determined by using conditional logistic regression. Sensitivity and specificity for predicting incident vertebral fracture were determined for lumbar spine and thoracic bone measurements., Results: Bone measurements from T8 and L2 predicted incident vertebral fracture equally well, regardless of fracture location. Specifically, for predicting vertebral fracture at any level, the odds ratio (per 1-SD decrease) for the vBMD and strength measurements at L2 and T8 ranged from 2.0 to 2.7 (p < 0.0001) and 1.8 to 2.8 (p < 0.0001), respectively. Results were similar when predicting fracture only in the thoracic versus the thoracolumbar spine. Lumbar and thoracic spine bone measurements had similar sensitivity and specificity for predicting incident vertebral fracture., Conclusion: These findings indicated that like those from the lumbar spine, CT-based bone density and strength measurements from the thoracic spine may be useful for identifying individuals at high risk for vertebral fracture.

Objective: Obesity has been associated with cognitive decline in longitudinal studies of older individuals. We hypothesized that the cognitive sequelae of obesity may be detectable in the reproductive years. In addition, we explored the hypothesis that these associations may be mediated by the hormonal milieu., Design and Methods: Of 49 young healthy lean and overweight women aged 20-45, we investigated the association between performance on a battery of cognitive tests, body composition parameters [body mass index, total fat, abdominal (visceral, subcutaneous, and total) adipose tissue, and muscle], and hormone levels (insulin, adiponectin, leptin, insulin-like growth factor 1 (IGF-1), estrogen, testosterone, and vitamin D)., Results: We found a significant negative association between both visceral adiposity and muscle, and performance in the domain of verbal learning and memory, after controlling for age and education. Other body composition parameters showed similar trends (0.05 < P < 0.10). Additionally, the degree of insulin resistance was negatively associated with executive function domain. None of the associations between the other hormones examined (adipokines, IGF-1, gonadal hormones, and vitamin D) and cognitive function were significant., Conclusion: These preliminary findings suggest a possible association between obesity and cognitive function in healthy young women of reproductive age. More research is warranted into the potential modulatory effect of insulin resistance on this association., (Copyright © 2012 The Obesity Society.)

Objective: The purpose of our study was to assess the value of a modified three-point Dixon MR technique for evaluating articular cartilage defects in the knee joint on a low-field-strength open magnet, correlated with arthroscopy., Subjects and Methods: Twenty consecutive patients who underwent both MR imaging and arthroscopy of the knee joint for suspected internal derangement were examined. A modified three-point Dixon MR sequence with a single radiofrequency echo single-scan method for water and fat separation with correction of the static field inhomogeneities was performed on a 0.35-T open magnet to obtain fat suppression. The MR images were prospectively evaluated for the presence and grade of articular cartilage defects., Results: Uniform fat suppression was obtained in all patients using the modified three-point Dixon technique. Fifty-nine cartilage abnormalities were identified in 19 patients on the basis of arthroscopy. Forty-seven of 59 arthroscopically proven abnormalities were prospectively detected on MR imaging. Compared with arthroscopy, the overall sensitivity of the modified three-point Dixon technique in detecting cartilage lesions was 80% and the specificity was 73%. Sixty-five percent of the cartilage abnormalities were graded identically on MR imaging and arthroscopy., Conclusion: The modified three-point Dixon sequence is a useful technique for achieving fat suppression in the knee joint on a 0.35-T open magnet. It is a sensitive and specific technique for the assessment of cartilage abnormalities in the knee.

Purpose: To assess the value of central quality assurance (QA) reading of transvaginal ultrasonographic (US) images obtained to measure endometrial thickness and to assess image quality., Materials and Methods: Results of 2,000 US examinations performed in 1,000 subjects during one of two multicenter drug trials were evaluated. Endometrial thickness was measured at the study site; images were then sent to the QA center, where an experienced sonologist evaluated endometrial thickness and image quality., Results: In 360 (18%) of the 2,000 examinations, image quality was insufficient for central QA reading. Repeat examinations were requested, and suggestions for improvement in technique were provided. In 349 (97%) of the 360 examinations, repeat US images were of acceptable quality. In 99 (5%) of the 1,989 examinations in which endometrial thickness was measured, central measurement of thickness differed by more than 2 mm from that of the site. In a group (n = 300) that was followed up for 1 year, requests for repeat US examinations decreased from 24% at baseline to 11% at 1 year., Conclusion: Central QA reading provides a consistent evaluation of endometrial thickness on US images obtained in multicenter drug trials and helps to ensure the acquisition of high-quality transvaginal US images. It further leads to demonstrable improvement in site performance.

Objective: The purpose of this paper was to use MR imaging to determine whether a relationship exists between lateral epicondylitis and abnormalities of the lateral ulnar collateral ligament., Subjects and Methods: The study group comprised 35 consecutive patients who were referred for MR imaging to rule out lateral epicondylitis. On MR imaging, "lateral epicondylitis" was defined as increased signal intensity of the extensor tendons close to their insertion on the lateral epicondyle. The severity of the lateral epicondylitis was graded as mild, moderate, or severe. The origin of the lateral collateral ligamentous complex was characterized, and the lateral ulnar collateral ligament was graded as normal, thickened, partially torn, or torn. Eleven patients underwent elbow surgery after the initial MR examination., Results: In 15 patients, MR imaging revealed characteristics of mild lateral epicondylitis. In 13 of these patients, the lateral ulnar collateral ligament was normal; one patient showed a thickened ligament; and one patient had a thinned ligament. In 11 patients, MR imaging showed features of moderate lateral epicondylitis. In eight of these patients, the lateral ulnar collateral ligament was thickened, and in the remaining three patients the ligament was normal. All nine patients with severe lateral epicondylitis showed abnormalities of the lateral ulnar collateral ligament on MR imaging. In one of these patients the lateral ulnar collateral ligament was thickened, in three patients we saw a partial tear, and in the remaining five patients we saw a complete tear of the ligament., Conclusion: In our study, MR imaging features of lateral epicondylitis were often associated with thickening and tears of the lateral ulnar collateral ligament.

Objective: The purpose of this study was to assess the accuracy of routine T2-weighted MR imaging in detecting and grading articular cartilage lesions in the knee compared with arthroscopy., Subjects and Methods: We examined 130 consecutive patients who underwent MR imaging and arthroscopy of the knee for suspected internal derangement. MR imaging consisted of axial and coronal T2-weighted fast spin-echo sequences with fat saturation and sagittal T2-weighted spin-echo sequences. Each single plane was evaluated and graded for the presence and appearance of articular cartilage defects using a standard arthroscopic grading scheme adapted to MR imaging., Results: Of the 86 arthroscopically proven abnormalities, 81 were detected on MR imaging. Sensitivity of the T2-weighted fast spin-echo sequence with fat saturation was 61% for the coronal plane alone and 59% for the axial plane alone. Specificity for each plane was 99%. Sensitivity for the sagittal T2-weighted spin-echo sequence was 40%, and specificity was 100%. Sensitivity of the combination of axial and coronal T2-weighted fast spin-echo sequences with fat saturation and sagittal T2-weighted spin-echo sequence compared with arthroscopy for revealing cartilage lesions was 94%, specificity was 99%, and accuracy was 98%. Sensitivity of coronal and axial T2-weighted fast spin-echo sequences with fat saturation was 93%, and specificity was 99%. Fifty-five lesions (64%) were identically graded on MR imaging and arthroscopy. Seventy-eight lesions (90%) were within one grade using MR imaging and arthroscopy, and 84 lesions (97%) were within two grades using MR imaging and arthroscopy., Conclusion: T2-weighted fast spin-echo MR imaging with fat saturation is an accurate and fast technique for detecting and grading articular cartilage defects in the knee. The combination of the axial and coronal planes offers sufficient coverage of articular surfaces to provide a high sensitivity and specificity for chondral defects.