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118


Bone and non-contractile soft tissue changes following open kinetic chain resistance training and testosterone treatment in spinal cord injury: an exploratory study

Holman, M E; Chang, G; Ghatas, M P; Saha, P K; Zhang, X; Khan, M R; Sima, A P; Adler, R A; Gorgey, A S
Twenty men with spinal cord injury (SCI) were randomized into two 16-week intervention groups receiving testosterone treatment (TT) or TT combined with resistance training (TT + RT). TT + RT appears to hold the potential to reverse or slow down bone loss following SCI if provided over a longer period.
PMID: 33443609
ISSN: 1433-2965
CID: 4771502

Metal artifacts of hip arthroplasty implants at 1.5-T and 3.0-T: a closer look into the B1 effects

Khodarahmi, Iman; Kirsch, John; Chang, Gregory; Fritz, Jan
OBJECTIVE:field on metal implant-induced artifacts of titanium (Ti) and cobalt-chromium (CoCr) hip arthroplasty implants at 1.5-T and 3.0-T field strengths. MATERIAL AND METHODS/METHODS:field as the system default, as well as 3.0-T, which permitted CP and EP. Manual segmentation quantified the size of the metal artifacts at the level of the acetabular cup, femoral neck, and femoral shaft. RESULTS:In the acetabular cup and femoral neck, 1.5-T CP achieved smaller artifact sizes than 3.0-T CP (28-29% on HBW-TSE, p = 0.002-0.005; 17-34% on SEMAC, p = 0.019-0.102) and 3.0-T EP (25-28% on HBW-TSE, p = 0.010-0.011; 14-36% on SEMAC, p = 0.058-0.135) techniques. In the femoral stem region, 3.0-T EP achieved more efficient artifact suppression than 3.0-T CP (HBW-TSE 44-45%, p < 0.001-0.022; SEMAC 76-104%, p < 0.001-0.022) and 1.5-T CP (HBW-TSE 76-96%, p < 0.001-0.003; SEMAC 138-173%, p = 0.003-0.005) techniques. CONCLUSION/CONCLUSIONS:Despite slightly superior metal reduction ability of the 1.5-T in the region of the acetabular cup and prosthesis neck, 3.0-T MRI of hip arthroplasty implants using elliptically polarized RF pulses may overall be more effective in reducing metal artifacts than the current standard 1.5-T MRI techniques, which by default implements circularly polarized RF pulses.
PMID: 32918566
ISSN: 1432-2161
CID: 4592282

Microbial-derived antigens and metabolites in spondyloarthritis

Yang, Katharine Lu; Lejeune, Alannah; Chang, Gregory; Scher, Jose U; Koralov, Sergei B
Spondyloarthritis (SpA) is a group of chronic, immune-mediated, inflammatory diseases affecting the bone, synovium, and enthesis. Microbiome, the community of microorganisms that has co-evolved with human hosts, plays a pivotal role in human health and disease. This invisible "essential organ" supplies the host with a myriad of chemicals and molecules. In turn, microbial metabolites can serve as messengers for microbes to communicate with each other and in the cross-talk with host cells. Gut dysbiosis in SpA is associated with altered microbial metabolites, and an accumulated body of research has contributed to the understanding that changes in intestinal microbiota can modulate disease pathogenesis. We review the novel findings from human and animal studies to provide an overview of the contribution of individual microbial metabolites and antigens to SpA.
PMID: 33569635
ISSN: 1863-2300
CID: 4779892

Lower extremity injuries U.S national fencing team members and U.S fencing Olympians

Thompson, Kamali; Chang, Gregory; Alaia, Michael; Jazrawi, Laith; Gonzalez-Lomas, Guillem
Introduction: Fencing is growing rapidly in popularity and competitiveness with fencers beginning at a younger age and competing in more tournaments. Even though fencing has a low risk of time-loss injury, fencers are inevitably going to experience injuries if proper athletic training and prevention does not occur. We aim to describe and compare the lower extremity injuries experienced by fencers that have trained at the highest level in the sport. We hypothesized that athletes who fenced longer would suffer more knee and hip injuries and report lower IKDC and HOS scores.Methods: This is an epidemiology study distributed to members of the U.S national team and Olympic team from 1980 to 2018. The electronic survey included questions regarding age, weapon, number of years fencing, number of national and Olympic teams, injuries on the dominant and nondominant hip and knee, time missed due to injury, and methods for treatment. The survey also included the International Knee Demographic Committee (IKDC) and Hip Outcome Score (HOS).Results: There were 153 national team members between July 1980 and July 2018, 110 with contact information. A total of 77 athletes submitted the survey, consisting of 30 females and 47 males. Female fencers had more hip injuries and lower IKDC and HOS scores than their male counterparts. In total, there were 71 injuries to the dominant (front) knee and 28 injuries to the nondominant (back) knee. There were 32 dominant hip injuries and 5 nondominant hip injuries. Saber fencers reported the most dominant and nondominant hip and knee injuries.Conclusion: The intense, repetitive and asymmetrical movements involved in fencing affect the weight bearing leg and the nondominant leg in all weapons. Special attention should be paid to female fencers as they experience more hip and knee injuries resulting in impaired joint function.
PMID: 33625317
ISSN: 2326-3660
CID: 4794682

Impact of COVID-19 Workflow Changes on Patient Throughput at Outpatient Imaging Centers

Chang, Gregory; Doshi, Ankur; Chandarana, Hersh; Recht, Michael
RATIONALE AND OBJECTIVES/OBJECTIVE:To determine the impact of COVID-19 workflow changes on patient throughput at the outpatient imaging facilities of a large healthcare system in New York City. MATERIALS AND METHODS/METHODS:COVID-19 workflow changes to permit social distancing and patient and staff safety included screening at the time of scheduling, encouraging patients to use our digital platform to complete registration/safety forms prior to appointments, stationing screeners at all entrances, limiting waiting room capacity, implementing a texting system to notify patients of delays, limiting dressing room use by encouraging patients to wear exam-appropriate clothing, and accelerating MRI protocols without reducing image quality. We assessed patients' pre-exam wait times, MR exam times, overall time spent on site, and registration for and use of the digital portal before (February 2020) and after (June 2020) implementation of these measures. RESULTS:Across 17 outpatient imaging centers, workflow changes resulted in a 23.1% reduction (-6.8 minutes) in all patients' pre-exam wait times (p <0.00001). Pre-exam wait times for MRI, CT, ultrasound, x-ray, and mammography decreased 28.4% (-10.3 minutes), 16.5% (-6.7 minutes), 25.3% (-7.7 minutes), 22.8% (-3.7 minutes), and 23.9% (-5.0 minutes), respectively (p < 0.00001 for all). MR exam times decreased 9.7% (-3.5 minutes) and patients' overall time on site decreased 15.2% (-8.0 minutes). The proportions of patients actively using the digital patient portal (56.1%-70.1%) and completing forms electronically prior to arrival (24.9%-47.1%) increased (p < 0.0001 for both). CONCLUSION/CONCLUSIONS:Workflow changes necessitated by the COVID-19 pandemic to ensure safety of patients and staff have permitted higher outpatient throughput.
PMCID:7831631
PMID: 33516590
ISSN: 1878-4046
CID: 4775672

Musculoskeletal MR Imaging Applications at Ultra-High (7T) Field Strength

Menon, Rajiv G; Chang, Gregory; Regatte, Ravinder R
Regulatory approval of ultrahigh field (UHF) MR imaging scanners for clinical use has opened new opportunities for musculoskeletal imaging applications. UHF MR imaging has unique advantages in terms of signal-to-noise ratio, contrast-to-noise ratio, spectral resolution, and multinuclear applications, thus providing unique information not available at lower field strengths. But UHF also comes with a set of technical challenges that are yet to be resolved and may not be suitable for all imaging applications. This review focuses on the latest research in musculoskeletal MR imaging applications at UHF including morphologic imaging, T2, T2∗, and T1ρ mapping, chemical exchange saturation transfer, sodium imaging, and phosphorus spectroscopy imaging applications.
PMID: 33237012
ISSN: 1557-9786
CID: 4679242

Finite element modelling of trabecular bone microstructure using emerging CT images

Chapter by: Guha, Indranil; Rajapakse, Chamith S.; Zhang, Xiaoliu; Chang, Gregory; Saha, Punam
in: Progress in Biomedical Optics and Imaging - Proceedings of SPIE by
[S.l.] : SPIE, 2021
pp. ?-?
ISBN: 9781510640290
CID: 4859972

MR fingerprinting for rapid simultaneous T1 , T2 , and T1ρ relaxation mapping of the human articular cartilage at 3T

Sharafi, Azadeh; Zibetti, Marcelo V W; Chang, Gregory; Cloos, Martijn; Regatte, Ravinder R
PURPOSE/OBJECTIVE:To implement a novel technique for simultaneous, quantitative multiparametric mapping of the knee articular cartilage. METHODS:relaxation time (P = .02) in medial femoral cartilage. CONCLUSION/CONCLUSIONS:
PMID: 32385949
ISSN: 1522-2594
CID: 4439232

Quantitative 3T MRI of multiple adipose tissue in osteoporosis patient with varying fracture risk [Meeting Abstract]

Martel, D; Honig, S; Chang, G
Purpose: Osteoporosis (OP) is a disease of weak bone associated with increased fracture risk (Fx). An important component of bone tissue is bone marrow adipose tissue (BAT), which has been previously associated with Fx and OP. Recent studies have shown an association between BMD and fat quantity in the spine and femur using Chemical Shift Encoded MRI (CSE-MRI). The aim of our study was to apply CSE-MRI in thigh muscle (MUS), BAT, and subcutaneous fat (SAT) of the pelvic region in osteoporosis patients with varying degrees of Fx.
Material(s) and Method(s): This study had institutional review board approval and written informed consent was obtained from all n=128 recruited female subjects with OP. Patients were divided into three groups for analysis based upon overall FRAX score: low (LOW, FRAX < 10, n=42, 57+/-6.9y, BMI 23+/-4.1 kg/m2), moderate (MOD, 10>FRAX>20, n=52, 62+/-6.9y, BMI 22+/-3.4 kg/m2) and high (HIGH, FRAX>20, n=34, 64+/-5.8y, BMI 22+/-3.1 kg/m2). 3T MRI acquisition were performed a 3T using a 3D spoiled gradient-echo sequence. An automatic reconstruction pipeline allowed computation of proton density fat fraction (PDFF), susceptibility mapping (QSM) and R2*. BAT, MUS and SAT were segmented by thresholding the PDFF map. An unpaired one-way ANOVA test was used to assess significant differences.
Result(s): Overall, in BAT, we found a higher amount of PDFF in HIGH subjects compared to LOW subjects (+5%, p= 0.032). In muscle, we found a higher amount of PDFF in HIGH compared to both LOW (+8.87%, p =0.008) and MOD subjects (+9.25%, p= 0.006). There were no differences between groups with regards to R2*measured. We found diamagnetic BAT and MUS and paramagnetic SAT. Susceptibility of SAT was higher in LOW compared to both HIGH (-31%, p= 0.008) and MOD (-23%, p= 0.04) subjects. Volume of MUS was lower in MOD compared to LOW (-8%, p=0.009) and HIGH (-9%, p=0.045).
Conclusion(s): Our result suggests that fracture risk is related to an increased amount of adipose tissue. 3T CSE-MRI could be used in the future to study the relationship between adipose tissue and bone health and possibly even provide an additional surrogate marker of Fx beyond BMD
EMBASE:634143612
ISSN: 1432-2161
CID: 4792472

The combination of an inflammatory peripheral blood gene expression and imaging biomarkers enhance prediction of radiographic progression in knee osteoarthritis

Attur, Mukundan; Krasnokutsky, Svetlana; Zhou, Hua; Samuels, Jonathan; Chang, Gregory; Bencardino, Jenny; Rosenthal, Pamela; Rybak, Leon; Huebner, Janet L; Kraus, Virginia B; Abramson, Steven B
OBJECTIVE:Predictive biomarkers of progression in knee osteoarthritis are sought to enable clinical trials of structure-modifying drugs. A peripheral blood leukocyte (PBL) inflammatory gene signature, MRI-based bone marrow lesions (BML) and meniscus extrusion scores, meniscal lesions, and osteophytes on X-ray each have been shown separately to predict radiographic joint space narrowing (JSN) in subjects with symptomatic knee osteoarthritis (SKOA). In these studies, we determined whether the combination of the PBL inflammatory gene expression and these imaging findings at baseline enhanced the prognostic value of either alone. METHODS:PBL inflammatory gene expression (increased mRNA for IL-1β, TNFα, and COX-2), routine radiographs, and 3T knee MRI were assessed in two independent populations with SKOA: an NYU cohort and the Osteoarthritis Initiative (OAI). At baseline and 24 months, subjects underwent standardized fixed-flexion knee radiographs and knee MRI. Medial JSN (mJSN) was determined as the change in medial JSW. Progressors were defined by an mJSN cut-point (≥ 0.5 mm/24 months). Models were evaluated by odds ratios (OR) and area under the receiver operating characteristic curve (AUC). RESULTS:We validated our prior finding in these two independent (NYU and OAI) cohorts, individually and combined, that an inflammatory PBL inflammatory gene expression predicted radiographic progression of SKOA after adjustment for age, sex, and BMI. Similarly, the presence of baseline BML and meniscal lesions by MRI or semiquantitative osteophyte score on X-ray each predicted radiographic medial JSN at 24 months. The combination of the PBL inflammatory gene expression and medial BML increased the AUC from 0.66 (p = 0.004) to 0.75 (p < 0.0001) and the odds ratio from 6.31 to 19.10 (p < 0.0001) in the combined cohort of 473 subjects. The addition of osteophyte score to BML and PBL inflammatory gene expression further increased the predictive value of any single biomarker. A causal analysis demonstrated that the PBL inflammatory gene expression and BML independently influenced mJSN. CONCLUSION/CONCLUSIONS:The use of the PBL inflammatory gene expression together with imaging biomarkers as combinatorial predictive biomarkers, markedly enhances the identification of radiographic progressors. The identification of the SKOA population at risk for progression will help in the future design of disease-modifying OA drug trials and personalized medicine strategies.
PMID: 32912331
ISSN: 1478-6362
CID: 4589512