Faculty Bibliography

PURPOSE: To develop an accelerated SEMAC metal implant MRI technique (Sparse-SEMAC) with reduced scan time and improved metal distortion correction. METHODS: Sparse-SEMAC jointly exploits the inherent sparsity along the additional phase-encoding dimension and multicoil encoding capabilities to significantly accelerate data acquisition. A prototype pulse sequence with pseudorandom ky -kz undersampling and an inline image reconstruction was developed for integration in clinical studies. Three patients with hip implants were imaged using the proposed Sparse-SEMAC with eight-fold acceleration and compared with the standard-SEMAC technique used in clinical studies (three-fold GRAPPA acceleration). Measurements were performed with SEMAC-encoding steps (SES) = 15 for Sparse-SEMAC and SES = 9 for Standard-SEMAC using high spatial resolution Proton Density (PD) and lower-resolution STIR acquisitions. Two expert musculoskeletal (MSK) radiologists performed a consensus reading to score image-quality parameters. RESULTS: Sparse-SEMAC enables up to eight-fold acceleration of data acquisition that results in two-fold scan time reductions, compared with Standard-SEMAC, with improved metal artifact correction for patients with hip implants without degrading spatial resolution. CONCLUSION: The high acceleration enabled by Sparse-SEMAC would enable clinically feasible examination times with improved correction of metal distortion. Magn Reson Med, 2016. (c) 2016 Wiley Periodicals, Inc.

Purpose: Quantification of tendon retraction is paramount in the surgical decision-making algorithm for proximal hamstring avulsion injury. Not only is it used to determine if surgery is indicated, but it may lead the surgeon to change the pre-operative plan from a more aesthetically-appealing gluteal fold incision to a more extensile, longitudinally-based proximal thigh incision. However, the hamstring origin on the ischial tuberosity is broad. Variability in location on the ischial tuberosity used as the proximal landmark and occasional difficulty in locating the proximal tendon stump may lead to differences in perceived retraction, altering the surgical decision making process. We hypothesize there will be substantial variability in the ischial tuberosity location used as the proximal marker, not only between orthopaedists and radiologists, but also amongst radiologists themselves. Materials and Methods: Two surveys were created for the purpose of this study. One survey was sent to members of the Society of Skeletal Radiology (SSR), querying the preferred ischial tuberosity landmark, perceived difficulties in quantifying retraction, and the impact of radiology measurements on clinical decision making. A similar survey, with added questions on the impact of imaging findings in clinical management was approved and posted onto the American Orthopaedic Society for Sports Medicine (AOSSM) website. Results: Two hundred and fifteen SSR members responded to the survey. For cases of complete and partial hamstring avulsion, there was variability among musculoskeletal (MSK) radiologists in the proximal landmark used for quantification of retraction, with n = 100 (47%) using the conjoint tendon origin, n = 84 (39%) using the semimembranosus tendon origin, and n = 31(14%) using the posterior-inferior edge of the ischial tuberosity. Difficulty in determining location of the retracted tendon stump was reported by n = 93(44%) of MSK radiologists. Most MSK radiologists (n = 118, 55%) reported measurements in their dictation and were unsure as to whether or not they are used to guide clinical management. Results of the second survey posted by AOSSM will be subsequently reported when available. Conclusion: Differences in choosing an ischial tuberosity landmark and occasional difficulty in locating the proximal tendon stump may lead to substantial variability in measured tendon retraction among MSK radiologists in cases of proximal hamstring avulsion. Radiologists should consider a standardized approach to measuring tendon retraction or should clearly stipulate the location of the proximal landmark in their reports

Purpose: Rotator cuff pathology is typically seen inmiddle age or elderly patients and is unusual in young patients. We have recently noted rotator cuff tendinosis and partial thickness tendon tears in several young (<21 years of age) patients with a history of competitive swimming. The purpose of this study was to determine the frequency of such injuries and to determine if there was any specific pattern of rotator cuff pathology in young competitive swimmers. Materials and Methods: A retrospective review of our MRI database between 2006 through 2016 was performed using the search terms "swimmer" and swimming in patients younger than 21 years of age who had shoulder MRIs. MRIs were reviewed for rotator cuff tendinosis and tears using the criteria described in the literature. A control group was comprised of 20 patients with similar age group who had shoulder MRIs and no history of competitive swimming. Results: There were 17 patients who fit our inclusion criteria; 10 females and 7 males. All were described in the history as competitive swimmers presenting with shoulder pain. The ages of these patients ranged from 11 to 19 years of age (average 14). There were 7 (41%) patients with rotator cuff pathology. Four of these patients had supraspinatus tendinosis and 2 had co-existing infraspinatus tendinosis. Additionally, 3 patients had low grade (less than 25% thickness of tendon) articular sided partial-tears involving supraspinatus tendon with underlying tendinosis. There were no full thickness tears. The subscapularis and teres minor tendons were normal in all patients. No rotator cuff tendinosis or tears were identified in the control group of patients. Conclusion: Rotator cuff pathology is typically the result of chronic repetitive injury and seen in middle aged to older patients. Competitive swimming appears to increase the risk of rotator cuff injury in young patients most likely due to repetitive overhead motion. The pathology typically presents as tendinosis or low grade partial thickness tears of the supraspinatus tendon

The primary goal of comparative effectiveness research (CER) is to define the optimal choice among alternative diagnostic and interventional strategies for a given clinical scenario among major stakeholders in the health care system. In an era where health care decision makers are demanding greater evidence of improved patient outcomes from the use of medical technologies, musculoskeletal (MSK) imagers must be more engaged in generating quality CER. We provide an overview of CER and its expanding role in U.S. health care, the current funding environment for CER and MSK imaging, potential areas for CER in MSK radiology, and a discussion of foreseeable challenges for CER in MSK imaging.