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1.
J Surg Res ; 296: 456-464, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38320365

ABSTRACT

BACKGROUND: Primary hyperparathyroidism (PHPT) is underdiagnosed and associated with many adverse health effects. Historically, many hypercalcemic patients have not received parathyroid hormone (PTH) testing; however, underlying reasons are uncertain. Our goals are to determine the PTH testing rate among hypercalcemic individuals at a large academic health system and to assess for characteristics associated with testing versus not testing for PHPT to inform future strategies for closing testing gaps. METHODS: This retrospective study included adult patients with ≥1 elevated serum calcium result between 2018 and 2022. Based on the presence or absence of a serum PTH result, individuals were classified as "screened" versus "unscreened" for PHPT. Demographic and clinical characteristics of these groups were compared. RESULTS: The sample comprised 17,491 patients: 6567 male (37.5%), 10,924 female (62.5%), mean age 59 y. PTH testing was performed in 6096 (34.9%). Characteristics independently associated with the greatest odds of screening were 5+ elevated calcium results (odds ratio [OR] 5.02, P < 0.0001), chronic kidney disease (OR 3.63, P < 0.0001), maximum calcium >12.0 mg/dL (OR 2.48, P < 0.0001), and osteoporosis (OR 2.42, P < 0.0001). Characteristics associated with lowest odds of screening were age <35 y (OR 0.60, P < 0.0001), death during the study period (OR 0.68, P < 0.0001), age ≥85 y (OR 0.70, P = 0.0007), and depression (OR 0.84; P = 0.0081). CONCLUSIONS: Only 35% of hypercalcemic patients received PTH testing. Although the presence of PHPT-associated morbidity was generally associated with increased rates of screening, hypercalcemic patients with depression were 16% less likely to be tested.


Subject(s)
Hypercalcemia , Hyperparathyroidism, Primary , Adult , Humans , Male , Female , Middle Aged , Hypercalcemia/diagnosis , Hypercalcemia/etiology , Calcium , Hyperparathyroidism, Primary/complications , Hyperparathyroidism, Primary/diagnosis , Retrospective Studies , Parathyroid Hormone
2.
AJR Am J Roentgenol ; 222(1): e2329889, 2024 01.
Article in English | MEDLINE | ID: mdl-37877596

ABSTRACT

BACKGROUND. Sarcopenia is commonly assessed on CT by use of the skeletal muscle index (SMI), which is calculated as the skeletal muscle area (SMA) at L3 divided by patient height squared (i.e., a height scaling power of 2). OBJECTIVE. The purpose of this study was to determine the optimal height scaling power for SMA measurements on CT and to test the influence of the derived optimal scaling power on the utility of SMI in predicting all-cause mortality. METHODS. This retrospective study included 16,575 patients (6985 men, 9590 women; mean age, 56.4 years) who underwent abdominal CT from December 2012 through October 2018. The SMA at L3 was determined using automated software. The sample was stratified into two groups: 5459 patients without major medical conditions (based on ICD-9 and ICD-10 codes) who were included in the analysis for determining the optimal height scaling power and 11,116 patients with major medical conditions who were included for the purpose of testing this power. The optimal scaling power was determined by allometric analysis (whereby regression coefficients were fitted to log-linear sex-specific models relating height to SMA) and by analysis of statistical independence of SMI from height across scaling powers. Cox proportional hazards models were used to test the influence of the derived optimal scaling power on the utility of SMI in predicting all-cause mortality. RESULTS. In allometric analysis, the regression coefficient of log(height) in patients 40 years old and younger was 1.02 in men and 1.08 in women, and in patients older than 40 years old, it was 1.07 in men and 1.10 in women (all p < .05 vs regression coefficient of 2). In analyses for statistical independence of SMI from height, the optimal height scaling power (i.e., those yielding correlations closest to 0) was, in patients 40 years old and younger, 0.97 in men and 1.08 in women, whereas in patients older than 40 years old, it was 1.03 in men and 1.09 in women. In the Cox model used for testing, SMI predicted all-cause mortality with a higher concordance index using of a height scaling power of 1 rather than 2 in men (0.675 vs 0.663, p < .001) and in women (0.664 vs 0.653, p < .001). CONCLUSION. The findings support a height scaling power of 1, rather than a conventional power of 2, for SMI computation. CLINICAL IMPACT. A revised height scaling power for SMI could impact the utility of CT-based sarcopenia diagnoses in risk assessment.


Subject(s)
Sarcopenia , Male , Humans , Female , Middle Aged , Adult , Sarcopenia/etiology , Retrospective Studies , Muscle, Skeletal/pathology , Proportional Hazards Models , Tomography, X-Ray Computed/methods
3.
Semin Musculoskelet Radiol ; 28(1): 78-91, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38330972

ABSTRACT

The importance and impact of imaging biomarkers has been increasing over the past few decades. We review the relevant clinical and imaging terminology needed to understand the clinical and research applications of body composition. Imaging biomarkers of bone, muscle, and fat tissues obtained with dual-energy X-ray absorptiometry, computed tomography, magnetic resonance imaging, and ultrasonography are described.


Subject(s)
Body Composition , Magnetic Resonance Imaging , Humans , Body Composition/physiology , Absorptiometry, Photon/methods , Magnetic Resonance Imaging/methods , Ultrasonography , Tomography, X-Ray Computed/methods
4.
Skeletal Radiol ; 53(3): 515-524, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37684434

ABSTRACT

PURPOSE: This study examines clinical, functional, and CT metrics of sarcopenia and all-cause mortality in older adults undergoing outpatient imaging. METHODS: The study included outpatients ≥ 65 years of age undergoing CT or PET/CT at a tertiary care institution. Assessments included screening questionnaires for sarcopenia (SARC-F) and frailty (FRAIL scale), and measurements of grip strength and usual gait speed (6 m course). Skeletal muscle area (SMA), index (SMI, area/height2) and density (SMD) were measured on CT at T12 and L3. A modified SMI was also examined (SMI-m, area/height). Mortality risk was studied with Cox proportional hazard analysis. RESULTS: The study included 416 patients; mean age 73.8 years [sd 6.2]; mean follow-up 2.9 years (sd 1.34). Abnormal grip, SARC-F, and FRAIL scale assessments were associated with higher mortality risk (HR [95%CI] = 2.0 [1.4-2.9], 1.6 [1.1-2.3], 2.0 [1.4-2.8]). Adjusting for age, higher L3-SMA, T12-SMA, T12-SMI and T12-SMI-m were associated with lower mortality risk (HR [95%CI] = 0.80 [0.65-0.90], 0.76 [0.64-0.90], 0.84 [0.70-1.00], and 0.80 [0.67-0.90], respectively). T12-SMD and L3-SMD were not predictive of mortality. After adjusting for abnormal grip strength and FRAIL scale assessments, T12-SMA and T12-SMI-m remained predictive of mortality risk (HR [95%CI] = 0.83 [0.70-1.00] and 0.80 [0.67-0.97], respectively). CONCLUSION: CT areal metrics were weaker predictors of all-cause mortality than clinical and functional metrics of sarcopenia in our older patient cohort; a CT density metric (SMD) was not predictive. Of areal CT metrics, SMI (area/height2) appeared to be less effective than non-normalized SMA or SMA normalized by height1.


Subject(s)
Sarcopenia , Humans , Aged , Sarcopenia/diagnostic imaging , Positron Emission Tomography Computed Tomography , Muscle, Skeletal/pathology , Tomography, X-Ray Computed
5.
AJR Am J Roentgenol ; 221(1): 137-138, 2023 07.
Article in English | MEDLINE | ID: mdl-36722760

ABSTRACT

Ageism is an increasingly recognized form of cognitive bias involving stereotypes, prejudice, and discrimination directed toward people on the basis of their age. Age-based bias influences how medicine is practiced and can result in profoundly negative but avoidable health outcomes. Awareness and education regarding ageism and its manifestations can improve the ability to identify and mitigate ageism. As this Viewpoint describes, radiologists are well situated to be part of the solution in addressing ageism.


Subject(s)
Ageism , Humans , Ageism/psychology , Stereotyping , Aging/psychology , Bias , Surveys and Questionnaires
6.
AJR Am J Roentgenol ; 2023 Aug 23.
Article in English | MEDLINE | ID: mdl-37610777

ABSTRACT

The purpose of this article is to review steatosis and fibrosis of skeletal muscle, focusing on older adults. Although CT, MRI, and ultrasound are commonly used to image skeletal muscle and provide diagnoses for a variety of medical conditions, quantitative assessment of muscle steatosis and fibrosis is uncommon. This review provides radiologists with a broad perspective on muscle steatosis and fibrosis in older adults by considering their public health impact, biologic mechanisms, and evaluation using CT, MRI, and ultrasound. Promising directions in clinical research that employ artificial intelligence algorithms and the imaging assessment of biologic age are also reviewed. The presented imaging methods hold promise for improving the evaluation of common conditions affecting older adults including sarcopenia, frailty, and cachexia.

7.
Skeletal Radiol ; 51(3): 513-524, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34268590

ABSTRACT

Sarcopenia is defined as the loss of muscle mass, strength, and function. Increasing evidence shows that sarcopenia is common in patients with rheumatic disorders. Although sarcopenia can be diagnosed using bioelectrical impedance analysis or DXA, increasingly it is diagnosed using CT, MRI, and ultrasound. In rheumatic patients, CT and MRI allow "opportunistic" measurement of body composition, including surrogate markers of sarcopenia, from studies obtained during routine patient care. Recognition of sarcopenia is important in rheumatic patients because sarcopenia can be associated with disease progression and poor outcomes. This article reviews how opportunistic evaluation of sarcopenia in rheumatic patients can be accomplished and potentially contribute to improved patient care.


Subject(s)
Sarcopenia , Body Composition , Humans , Muscle, Skeletal/pathology , Radiologists , Rheumatologists , Sarcopenia/diagnostic imaging
8.
AJR Am J Roentgenol ; 216(2): 447-452, 2021 02.
Article in English | MEDLINE | ID: mdl-32755177

ABSTRACT

OBJECTIVE. The purpose of this study was to investigate whether systematic bias in attenuation measurements occurs among CT scanners made by four major manufacturers and the relevance of this bias regarding opportunistic screening for osteoporosis. MATERIALS AND METHODS. Data on attenuation measurement accuracy were acquired using the American College of Radiology (ACR) accreditation phantom and were evaluated in a blinded fashion for four CT manufacturers (8500 accreditation submissions for manufacturer A; 18,575 for manufacturer B; 8278 for manufacturer C; and 32,039 for manufacturer D). The attenuation value for water, acrylic (surrogate for trabecular bone), and Teflon (surrogate for cortical bone; Chemours) materials for an adult abdominal CT technique (120 kV, 240 mA, standard reconstruction algorithm) was used in the analysis. Differences in attenuation value across all manufacturers were assessed using the Kruskal-Wallis test followed by a post hoc test for pairwise comparisons. RESULTS. The mean attenuation value for water ranged from -0.3 to 2.7 HU, with highly significant differences among all manufacturers (p < 0.001). For the trabecular bone surrogate, differences in attenuation values across all manufacturers were also highly significant (p < 0.001), with mean values of 120.9 (SD, 3.5), 124.6 (3.3), 126.9 (4.4), and 123.9 (3.4) HU for manufacturers A, B, C, and D, respectively. For the cortical bone surrogate, differences in attenuation values across all manufacturers were also highly significant (p < 0.001), with mean values of 939.0 (14.2), 874.3 (13.3), 897.6 (11.3), and 912.7 (13.4) HU for manufacturers A, B, C, and D, respectively. CONCLUSION. CT scanners made by different manufacturers show systematic offsets in attenuation measurement when compared with each other. Knowledge of these off-sets is useful for optimizing the accuracy of opportunistic diagnosis of osteoporosis.


Subject(s)
Osteoporosis/diagnostic imaging , Phantoms, Imaging , Tomography, X-Ray Computed/instrumentation , Accreditation , Bias , Educational Measurement , Humans , Reproducibility of Results
9.
Skeletal Radiol ; 50(3): 543-550, 2021 Mar.
Article in English | MEDLINE | ID: mdl-32892227

ABSTRACT

OBJECTIVE: To determine the relationship between CT-derived muscle metrics and standardized metrics of sarcopenia in patients undergoing routine CT imaging. MATERIALS AND METHODS: Data collected in 443 consecutive patients included body CT, grip strength, usual gait speed, and responses to SARC-F and FRAIL scale questionnaires. Functional and clinical metrics of sarcopenia were acquired at the time of CT. Metrics were analyzed using the diagnostic framework of the European Working Group on Sarcopenia in Older People (EWGSOP2). The skeletal muscle index (SMI) and skeletal muscle density (SMD) were measured at the T12 and L3 levels. Statistical methods include linear prediction models and ROC analysis. RESULTS: T12-SMD and L3-SMD in women and T12-SMD and L3-SMI in men show weak but significant (p < 0.05) predictive value for gait speed, after adjusting for subject age and body mass index. The prevalence of abnormal CT SMI at T12 and L3 was 29% and 71%, respectively, corresponding to prevalences of confirmed sarcopenia by EWGSOP2 of 10% and 15%, respectively. The agreement of abnormal SARC-F and FRAIL scale screening and EWGSOP2 confirmed sarcopenia was slight to fair (kappa: 0.20-0.28). CT cutpoints, based on EWGSOP2 criteria for abnormal grip strength or gait speed, are generally lower than cutpoints based on normative population data. CONCLUSION: Collection of clinical and functional sarcopenia information at the point of imaging care can be accomplished quickly and safely. CT-derived muscle metrics show convergent validity with gait speed. Only a minority of subjects with low CT metrics have confirmed sarcopenia by EWGSOP2 definition.


Subject(s)
Sarcopenia , Aged , Benchmarking , Cross-Sectional Studies , Female , Geriatric Assessment , Humans , Male , Sarcopenia/diagnostic imaging , Tomography, X-Ray Computed
10.
Skeletal Radiol ; 50(1): 69-78, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32607805

ABSTRACT

OBJECTIVE: Lumbar spine MRI interpretations have high variability reducing utility for surgical planning. This study evaluated a convolutional neural network (CNN) framework that generates automated MRI grading for its ability to predict the level that was surgically decompressed. MATERIALS AND METHODS: Patients who had single-level decompression were retrospectively evaluated. Sagittal T2 images were processed by a CNN (SpineNet), which provided grading for the following: central canal stenosis, disc narrowing, disc degeneration, spondylolisthesis, upper/lower endplate morphologic changes, and upper/lower marrow changes. The grades were used to calculate an aggregate score. The variables and the aggregate score were analyzed for their ability to predict the surgical level. For each surgical level subgroup, the surgical level aggregate scores were compared with the non-surgical levels. RESULTS: A total of 141 patients met the inclusion criteria (82 women, 59 men; mean age 64 years; age range 28-89 years). SpineNet did not identify central canal stenosis in 32 patients. Of the remaining 109, 96 (88%) patients had a decompression at the level of greatest stenosis. The higher stenotic grade was present only at the surgical level in 82/96 (85%) patients. The level with the highest aggregate score matched the surgical level in 103/141 (73%) patients and was unique to the surgical level in 91/103 (88%) patients. Overall, the highest aggregate score identified the surgical level in 91/141 (65%) patients. The aggregate MRI score mean was significantly higher for the L3-S1 surgical levels. CONCLUSION: A previously developed CNN framework accurately predicts the level of microdecompression for degenerative spinal stenosis in most patients.


Subject(s)
Spinal Stenosis , Spondylolisthesis , Adult , Aged , Aged, 80 and over , Decompression, Surgical , Female , Humans , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/surgery , Magnetic Resonance Imaging , Male , Middle Aged , Retrospective Studies , Spinal Stenosis/diagnostic imaging , Spinal Stenosis/surgery , Spondylolisthesis/surgery
11.
Skeletal Radiol ; 50(1): 79-85, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32621061

ABSTRACT

OBJECTIVE: To determine association of body composition measurements on CT and PET with progression of smoldering myeloma to multiple myeloma. METHODS: A retrospective cohort study in 65 patients with smoldering myeloma and PET/CT at diagnosis was performed at a tertiary cancer center. Subjects were between 38 and 87 years of age (mean 64) and included 37 males. Primary outcome was progression-free survival as a function of bone, fat, and muscle metrics on CT and PET (measured at the level of L4 pedicles) and clinical confounders. CT metrics included attenuation of L4 and retroperitoneal fat and various indices derived from the psoas muscle. PET measures included SUVmax and SUVmean of L4, retroperitoneal fat, and psoas. Cox proportional hazards modeling was performed with entry and retention criteria of p < 0.1 and p < 0.05, respectively. RESULTS: SUVmax and SUVmean were associated for each compartment (R2 = 0.78-0.84), and SUVmean (SUV) was used for subsequent analyses. SUV of the L4 vertebral body was associated with attenuation of the L4 vertebral body (p = 0.0032). There was no association between SUV and CT for muscle and fat compartments. In the subset of patients with bone marrow biopsy results (n = 43), there was no association between SUV of L4 and plasma cell concentration on core biopsy or flow cytometry (p = 0.089 and 0.072, respectively). The final Cox model showed association with albumin (HR 0.29, 95%CI 0.088-0.93, p = 0.038), M protein (HR 1.31, 95%CI 1.021-1.68, p = 0.034), and SUV of L4 (HR 1.99, 95%CI 1.037-3.82, p = 0.039). CONCLUSION: SUV of L4 is a prognostic indicator in patients with smoldering myeloma.


Subject(s)
Fluorodeoxyglucose F18 , Multiple Myeloma , Bone Marrow , Humans , Male , Multimodal Imaging , Multiple Myeloma/diagnostic imaging , Positron Emission Tomography Computed Tomography , Positron-Emission Tomography , Radiopharmaceuticals , Retrospective Studies
12.
J Surg Oncol ; 122(5): 869-876, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32613648

ABSTRACT

BACKGROUND AND OBJECTIVES: Computed tomography (CT) measurements of sarcopenia have been proposed as biomarkers associated with outcomes in various cancers and have typically been evaluated at the L3 vertebral level. However, staging imaging for patients with extremity and truncal soft tissue sarcoma (STS) often only includes chest CT imaging which precludes evaluation at L3. Therefore, we sought to evaluate muscle metrics at T12 on standard staging chest CT scans and evaluate for correlation with overall and event-free survival in patients with STS. METHODS: CT chest imaging for 89 patients with intermediate and high-grade STS (53 male, 36 female; 58.5 ± 19.0 years old, follow-up 37.4 ± 27.1 months) was reviewed on PACS at T12 for skeletal muscle density (SMD) and skeletal muscle index (SMI). RESULTS: Overall survival increased with increased SMD on univariate (hazard ratio [HR] = 0.61 [0.43, 0.86]) and age-adjusted analysis (HR = 0.65 [0.42, 0.89]. Event-free survival also increased with increased SMD in univariate analyses (HR = 0.68 [0.49, 0.95]) but did not maintain significance after adjusting for age (HR = 0.68 [0.43, 1.07]). SMI was not a predictor of overall or event-free survival. CONCLUSIONS: Higher SMD measured on routinely obtained staging chest CTs in STS patients is associated with improved survival.


Subject(s)
Muscle, Skeletal/diagnostic imaging , Sarcoma/diagnostic imaging , Disease-Free Survival , Extremities/pathology , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Muscle, Skeletal/pathology , Neoplasm Staging , Retrospective Studies , Sarcoma/mortality , Sarcoma/pathology , Sarcopenia/diagnostic imaging , Sarcopenia/pathology , Survival Rate , Tomography, X-Ray Computed/methods , Torso/pathology
13.
AJR Am J Roentgenol ; 215(3): 582-594, 2020 09.
Article in English | MEDLINE | ID: mdl-32755187

ABSTRACT

OBJECTIVE. The purpose of this article is to review the emerging field of opportunistic CT, which can be used to screen patients for osteoporosis and sarcopenia. CONCLUSION. Although body composition measurements are not routinely obtained using CT, quantitative assessment of bone and muscle biomarkers on CT can add value to patient care. Automated bone and muscle measurements promise to transform the everyday practice of radiology without resulting in additional cost or radiation exposure for patients.


Subject(s)
Osteoporosis/diagnostic imaging , Sarcopenia/diagnostic imaging , Tomography, X-Ray Computed/methods , Biomarkers , Body Composition , Bone Density , Humans , Mass Screening/methods
14.
J Surg Orthop Adv ; 29(1): 36-38, 2020.
Article in English | MEDLINE | ID: mdl-32223864

ABSTRACT

Associations between age and fracture incidence, total number of fractures, and total number of injuries per occupant occurring in motor vehicle crashes were evaluated. An observational study of the Crash Injury Research and Engineering Network was conducted. Multivariable logistic regression and negative binomial models were used to relate age (2064, 65+ years) to fracture incidence, total number of fractures per occupant, and total number of injuries, adjusting for sex and change in vehicle velocity (deltav). Over 90% of occupants had at least one fracture for a total of 5,846 fracture injuries. The older age group experienced a 15% increase in the incidence of total injuries sustained compared to the younger group (Incident Rate Ratio = 1.15, 95% Confidence Interval = 1.081.23, p 0.0001). Older patients should be considered for polytrauma evaluation even with a lower energy motor vehicle crash. (Journal of Surgical Orthopaedic Advances 29(1):3639, 2020).


Subject(s)
Accidents, Traffic , Fractures, Bone , Aged , Female , Humans , Incidence , Logistic Models , Middle Aged , Motor Vehicles
15.
AJR Am J Roentgenol ; 213(5): 963-982, 2019 11.
Article in English | MEDLINE | ID: mdl-31339354

ABSTRACT

OBJECTIVE. The purpose of this article is to summarize the nomenclature of nonneoplastic conditions affecting subchondral bone through a review of the medical literature and expert opinion of the Society of Skeletal Radiology Subchondral Bone Nomenclature Committee. CONCLUSION. This consensus statement summarizes current understanding of the pathophysiologic characteristics and imaging findings of subchondral nonneoplastic bone lesions and proposes nomenclature to improve effective communication across clinical specialties and help avoid diagnostic errors that could affect patient care.


Subject(s)
Bone Diseases/classification , Cartilage Diseases/classification , Terminology as Topic , Humans
16.
J Clin Densitom ; 22(4): 472-483, 2019.
Article in English | MEDLINE | ID: mdl-31558404

ABSTRACT

In preparation for the International Society for Clinical Densitometry Position Development Conference (PDC) 2019 in Kuala Lumpur, Malaysia, a cross-calibration and precision task force was assembled and tasked to review the literature, summarize the findings, and generate positions to answer 4 related questions provided by the PDC Steering Committee, which expand upon the current ISCD official positions on these subjects. (1) How should a provider with multiple dual-energy X-ray absorptiometry (DXA) scanners of the same make and model calculate least significant change (LSC)? (2) How should a provider with multiple DXA systems with the same manufacturer but different models calculate LSC? (3) How should a provider with multiple DXA systems from different manufacturers and models calculate LSC? (4) Are there specific phantom procedures that one can use to provide trustworthy in vitro cross calibration for same models, different models, and different makes? Based on task force deliberations and the resulting systematic literature reviews, 3 new positions were developed to address these more complex scenarios not addressed by current official positions on single scanner cross calibration and LSC. These new positions provide appropriate guidance to large multiple DXA scanner providers wishing to offer patients flexibility and convenience, and clearly define good clinical practice requirements to that end.


Subject(s)
Absorptiometry, Photon/standards , Bone Density , Consensus Development Conferences as Topic , Osteoporosis/diagnosis , Quality Assurance, Health Care , Absorptiometry, Photon/instrumentation , Calibration , Equipment Design , Humans , Societies, Medical
17.
Aging Clin Exp Res ; 31(4): 491-501, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30043314

ABSTRACT

BACKGROUND: Diet and exercise can promote weight loss in older adults; however, there is potential to increase fracture risk due to loss of bone mineral density (BMD) known to accompany weight loss. Weight loss effects on measures of bone quality and strength are currently unknown. AIMS: The purpose of this study is to develop subject-specific finite-element (FE) models of the lumbar spine and study the effect of intentional weight loss on bone strength in a pilot data set. METHODS: Computed tomography (CT) scans of the lumbar spine of 30 overweight and obese (mean BMI = 29.7 ± 3.9 kg/m2), older adults (mean age = 65.9 ± 4.6 years) undergoing an 18-month intentional weight loss intervention were obtained at baseline and post-intervention. Measures of volumetric BMD (vBMD) and variable cortical thickness were derived from each subject CT scan. Development of the subject-specific FE models of the lumbar spine involved model morphing techniques to accelerate the development of the models. vBMD-derived material properties and cortical thickness measures were directly mapped to baseline and post-intervention models. Bone strength was estimated through simulation of a quasi-static uniaxial compression test. RESULTS: From baseline to 18-month post-weight loss intervention, there were statistically significant decreases in estimated bone strength (6.5% decrease; p < 0.05). Adjusting for baseline bone measures and gender revealed no statistically significant correlations between weight change and change in vBMD, cortical thickness, or bone strength. CONCLUSION: Integration of CT-based measures and FE models with conventional areal BMD can improve the understanding of the effects of intentional weight loss on bone health.


Subject(s)
Bone Density/physiology , Compressive Strength/physiology , Obesity/physiopathology , Weight Loss/physiology , Aged , Biomechanical Phenomena , Female , Finite Element Analysis , Humans , Lumbar Vertebrae/diagnostic imaging , Male , Middle Aged , Tomography, X-Ray Computed
18.
Surg Radiol Anat ; 41(12): 1445-1449, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31630237

ABSTRACT

PURPOSE: To assess normal distribution of fluid in the tendon sheaths of the ankle. METHODS: 21 healthy volunteers were evaluated. Bilateral ankle MRI was performed on a 3T unit with PD-weighted images with fat saturation. The images were interpreted by two radiologists separately, and the short-axis dimension of fluid amount was measured. Bland-Altman plots and correlation plots were used to assess consistency between readers. RESULTS: There were 13 men and 8 women. The mean age was 24.7 years. Fluid in the retromalleolar part of the peroneus longus was seen in three ankles of three volunteers and in the inframalleolar part in three ankles of three volunteers. Fluid in the retromalleolar part of the peroneus brevis was seen in four ankles of three volunteers and in the inframalleolar part in three ankles of two volunteers. Fluid in the retromalleolar part of the tibialis posterior was seen in 37 ankles of 20 volunteers and in the inframalleolar part in 38 ankles of 21 volunteers Fluid in the retromalleolar part of the flexor digitorum was seen in 14 ankles of eight volunteers and in the inframalleolar part in 11 ankles of eight volunteers Fluid in the retromalleolar part of the flexor hallucis longus was seen in 23 ankles of 16 volunteers and in the inframalleolar part in 17 ankles of 11 volunteers. CONCLUSION: Fluid is common in the retro- and inframalleolar parts of the medial tendons. Fluid is virtually absent in the peroneal tendons and anterior tendon sheaths in normal volunteers.


Subject(s)
Ankle Joint/anatomy & histology , Synovial Fluid/diagnostic imaging , Tendons/anatomy & histology , Adult , Ankle Joint/diagnostic imaging , Female , Healthy Volunteers , Humans , Magnetic Resonance Imaging , Male , Tendons/diagnostic imaging , Young Adult
19.
Surg Radiol Anat ; 41(1): 65-68, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30523385

ABSTRACT

PURPOSE: This study aimed at studying the MR imaging appearance of the tibiotalar ligament in asymptomatic volunteers. MATERIALS AND METHODS: Fourty-two ankles were imaged on a 3T MR system using proton density weighted images with fat saturation (TR, 2969 ms; TE 30 ms; NA, 2; slice thickness, 2.5 mm). Subjects with acute ankle conditions or history of previous trauma were not included in the study group. Images were obtained in the three orthogonal planes. The posterior tibiotalar ligament was assessed on coronal imaging, by consensus of two radiologists. The signal intensity was recorded as isointense, hypointense, or hyperintense relative to muscle. The morphology of the ligament was classified as homogenous or striated. Descriptive statistics were obtained. RESULTS: There were 8 men and 14 women with a mean age of 24.7 years (range 19-43 years). The ligaments were classified as hyperintense in 30/42 (70%) of ankles and isointense in 9/42 (21%) of ankles. A striated appearance was seen in 34/42 (80%) of ankles. CONCLUSION: The posterior deep deltoid ligament is commonly hyperintense. It is usually striated although it can be homogeneously hyperintense. This appearance simulates a tear.


Subject(s)
Ankle Joint/diagnostic imaging , Ligaments, Articular/diagnostic imaging , Magnetic Resonance Imaging/methods , Adult , Ankle Injuries/diagnostic imaging , Female , Healthy Volunteers , Humans , Ligaments, Articular/injuries , Male
20.
Can Assoc Radiol J ; 70(4): 408-415, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31685098

ABSTRACT

Various conditions may result in forefoot pain. Magnetic resonance (MR) imaging allows accurate assessment of many of these conditions. We provide an overview of forefoot disorders divided into bones, capsule and plantar plate, musculotendinous structures, neurovascular structures, and subcutaneous tissue. We review normal anatomical features as well as MR imaging findings of common disorders.


Subject(s)
Magnetic Resonance Imaging/methods , Metatarsalgia/diagnostic imaging , Toes/anatomy & histology , Toes/diagnostic imaging , Humans
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