Dual-energy X-ray Absorptiometry Reports Research Articles

Comparison of Bone Mineral Density in Children and Adolescents on CT Versus DEXA Scan.

Retrospective cross-sectional. To determine associations between Hounsfield Units (HU) within a Region of interest (ROI) on CT scans and Dual Energy X-ray Absorptiometry (DEXA) measurements in children and adolescents. HU on CT scans as a proxy for bone mineral density (BMD) is widely used in adults. However, the utility of CT as a proxy for BMD have not been evaluated in children and adolescents. Patients younger than 18 years with a lumbar spine CT scan and a DEXA within 6 months of each other were identified. A ROI was used to measure the HU at each lumbar vertebral body on mid-axial cuts. Charts were reviewed for demographics, medical co-morbidities and DEXA reports. Correlation coefficients were calculated between mean DEXA Z-score and HU value. Patients were also stratified by Z-score (≥ -1.0, between -1.0 and -2.0, and ≤-2.0) and matched by age and BMI to a cohort of healthy children and compared. A moderate correlation between mean DEXA Z-score and mean HU on CT was found (r2=0.42, P<0.001). After matching for age and BMI, 21 patients in each group between the age of 4 and 17 years were analyzed. The mean HU value of the control group was 231.69. When stratified by Z-score (≥ -1.0, between -1.0 and -2.0, and ≤-2.0), the mean HU values were 244.59, 216.50, and 176.54, respectively. Patients with a Z-score of ≤-2.0 had a significantly lower mean HU than age matched controls. HU on lumbar CT in children and adolescents with DEXA Z-scores less than -2.0, were lower when compared to healthy age and BMI matched controls. This study suggests that HU on opportunistic CT scans of the spine may be used as a reasonable proxy for BMD in the pediatric population.

Body composition and body mass index measures from 8 to 18 years old in children with cystic fibrosis

BackgroundHistorically, body mass index (BMI) >50th percentile has represented optimal nutritional status in children with cystic fibrosis (CF) due to its positive association with lung function. Body composition parameters including fat-free mass index (FFMI) have been suggested as a more physiological nutrition benchmark. Aims: (1) describe changes in body composition with age and gender; (2) assess the correlation between measures of nutritional status (FFMI-z, FMI-z, BMI-z) and lung function (forced expiratory volume in one second predicted; FEV1pp). MethodsThis retrospective, mixed cross-sectional and serial measures study consisted of children with CF (8 to 18 years) attending Sydney Children's Hospital (2007–2020). FFMI and fat mass index (FMI) were taken from biennial dual energy x-ray absorptiometry (DXA) scans. Z-scores were derived using Well's reference population [1]. Repeated measures correlation analyses assessed correlations between FFMI-z, FMI-z, and BMI-z with FEV1pp. Results339 DXA reports were analysed from 137 patients. There were slight downwards trends in BMI-z and FMI-z, and an upwards trend in FFMI-z with increasing age and across both genders. Females had higher FMI-z and FFMI-z than males from 12.5 years. There was a weak, positive correlation between FEV1pp and BMI-z (r = 0.14, p = 0.04), and FFMI-z (r = 0.25, p<0.001). FMI-z had no correlation with FEV1pp (r=-0.06, p = 0.41). ConclusionDeficits in FFMI exist despite increasing trends with age. FFMI-z and BMI-z had a weak, positive correlation with FEV1pp. In contemporary cohorts, nutritional status (reflected by surrogate markers such as FFMI and BMI) may be less influential upon lung function than in previous decades.[1]: Wells, J.C., et al. Body-composition reference data for simple and reference techniques and a 4-component model: a new UK reference child. Am. J. Clin. Nutr.96, 1316–1326 (2012).

Official position of the Brazilian Association of Bone Assessment and Metabolism (ABRASSO) on the evaluation of body composition by densitometry: part I (technical aspects)\u2014general concepts, indications, acquisition, and analysis

ObjectiveTo review the technical aspects of body composition assessment by dual-energy X-ray absorptiometry (DXA) and other methods based on the most recent scientific evidence.Materials and methodsThis Official Position is a result of efforts by the Scientific Committee of the Brazilian Association of Bone Assessment and Metabolism (Associação Brasileira de Avaliação Óssea e Osteometabolismo, ABRASSO) and health care professionals with expertise in body composition assessment who were invited to contribute to the preparation of this document. The authors searched current databases for relevant publications. In this first part of the Official Position, the authors discuss the different methods and parameters used for body composition assessment, general principles of DXA, and aspects of the acquisition and analysis of DXA scans.ConclusionConsidering aspects of accuracy, precision, cost, duration, and ability to evaluate all three compartments, DXA is considered the gold-standard method for body composition assessment, particularly for the evaluation of fat mass. In order to ensure reliable, adequate, and reproducible DXA reports, great attention is required regarding quality control procedures, preparation, removal of external artifacts, imaging acquisition, and data analysis and interpretation.

Bone Mineral Density Changes Within and Outside of RT Fields Used to Treat Cervical Cancer

Pelvic insufficiency fractures and decreased bone mineral density (BMD) can occur in women treated with radiotherapy (RT) for gynecologic cancers. The purpose of this study was to compare the magnitude of BMD changes inside and outside of the radiation field in patients treated with radiation +/- chemotherapy for cervical cancer.In an IRB-approved prospective study, women (N = 78) with cervical cancer were assessed with serial tomographic scans and dual-energy x-ray absorptiometry (DXA) scans to evaluate the incidence of pelvic fractures (previously reported) and post-treatment BMD changes. Patients were treated with definitive RT or chemoradiation (CRT) at a single institution between 09/2008 and 07/2015. DXA scans were obtained at baseline (before CRT), 3 months, 1 year, and 2 years after completion of therapy. Serial BMD values at L1, L2, L3 and L4 were extracted from DXA reports. Patients with a pre-treatment history of pelvic fractures, bone metastases, or pelvic RT were excluded. The current analysis focused on a subset of 78 patients whose RT fields had upper borders below L1 and above L4, permitting a comparison of BMD changes in the field (L4) with those in a vertebral body outside the field (L1). Linear mixed models (LMM) were performed to examine the impact of radiotherapy on BMD change over time, and were adjusted for covariates (age, menopausal status, BMI, number of chemotherapy cycles).The median age of 78 patients was 45.5 years (range 23-88); all received RT and 76/78 (97.5%) received concurrent CRT. Treatment was associated with a significant decline in BMD in all 4 lumbar vertebral bodies over time, P < 0.05 with nadir at 3 months (L4) and 1 year (L1). By pairwise comparisons at 3 months and 2 years after treatment, BMD in L4 (inside RT field, P = 0.037) significantly improved while BMD in L1 (outside RT field) did not significantly change. After controlling for covariates noted above, there was no significant difference in BMD between 3 months and 2 years. Levels of C-terminal telopeptide of type I collagen (P = 0.018), bone alkaline phosphatase (P < 0.001), and number of chemotherapy cycles (P = 0.031) were significant predictors of L1 BMD loss. A trend of higher BMD at all time points was found for patients who were premenopausal versus postmenopausal at study entry. At 1- and 2-years of follow-up, trends towards BMD at levels higher than baseline were seen for patients who received hormone replacement therapy (HRT) after RT.Significant BMD loss following radiation treatment in all lumbar vertebrae (both in and out of field) was observed. On multivariate analysis, in-field vertebral bodies experienced no additional significant BMD decline earlier than those out-of-field, suggesting multifactorial contributors to bone density loss. HRT may improve BMD recovery and emphasizes the need for HRT after radiotherapy in appropriate premenopausal women.J. Wu: None. D.S. Lakomy: None. B. Fellman: None. M.P. Salcedo: IGCS-International Gynecologic Cancer Society, Brazilian Federation of Gynecology and Obstetricians (FEBRASGO)/BRAZIL (Federação Brasileira de Ginecologia e Obstetricia, FEBRASGO). A. Sood: Consultant; Kiyatec, Astra Zeneca. Stock; BioPath. sponsored research; M-Trap. A. Jhingran: American Board of Radiology. A.H. Klopp: Research Grant; MD Anderson Cancer Center SPORE Grant. R.B. Iyer: None. C. Jimenez: None. L. Colbert: None. K. Schmeler: None. P.J. Eifel: Travel Expenses; National Cancer Center Network. Stock; Apple Computer. L.L. Lin: Employee; VA Hospital. Research Grant; AstraZeneca. Travel Expenses; AstraZeneca.

DXA-Derived Adiposity and Lean Indices for Management of Cardiometabolic and Musculoskeletal Frailty: Data Interpretation Tricks and Reporting Tips.

The proper assessment and follow-up of obesity and sarcopenia are relevant for the proper management of the complications of cardiometabolic and musculoskeletal frailty. A total body dual-energy X-ray absorptiometry (DXA) scan should be systematically incorporated in the rehabilitative routine management of patients with obesity and sarcopenia. In the former patients, the total body DXA can be used to assess the fat tissue amount and distribution, while in the latter patients, it can be used to quantify the reduction of appendicular lean mass and to investigate the inter-limb lean mass asymmetry. This tutorial article provides an overview of different DXA-derived fat and lean indices and describes a step-by-step procedure on how to produce a complete DXA report. We suggest that the systematic incorporation of these indices into routine examinations of the patients with obesity and sarcopenia can be useful for identifying the patients at risk for cardiometabolic and neuromuscular impairment-related comorbidities and for evaluating the effectiveness of pharmacological and rehabilitative interventions.

DXA2: An Automated Program for Extraction of Dual-Energy X-Ray Absorptiometry Data

Introduction/Background: Since the 1970s imaging devices have been rapidly advancing to provide researchers, clinicians, radiologists, and practitioners greater capabilities to image bone. Today, dual-energy X-ray absorptiometry (DXA) has emerged as the gold standard for the assessment of bone and body composition. Despite recent improvements in DXA image quality and reduced radiation dosages and scan times, the data extraction process has yet to be streamlined. The objective of this study was to design an application to allow DXA users to quickly and accurately transfer DXA report data directly into a user-friendly format. Methodology: Initial development of the DXA Data Xtraction Assistant (DXA2) included processing 485 DXA reports from a previous study. Using Python script, numeric data from these DXA reports were converted to .csv files and then merged into one file, effectively compiling and organizing all table data from each report, by participant and visit number. A graphical user interface was then developed and beta tested using multiple DXA manufacturers, models, and software versions. To compare the effectiveness of the DXA2 to the current standard of manual extraction, all 485 reports were manually transcribed into Microsoft Excel. The time required per report and the error rates were compared. Results: Manual transcription, by an experienced researcher, took over 10 h with an error rate of 0.6% and average error magnitude of 51%. Data extraction from DXA2 took less than 25 min to retrospectively reformat all DXA reports for the DXA2 and transcribe all 485 reports with 100% accuracy. Conclusion: The DXA2 application automates DXA report data extraction and aggregation for clinical, research, and applied settings and drastically reduces manual data entry time and eliminates transcription errors.

Radiofrequency Echographic Multi Spectrometry (REMS) for the diagnosis of osteoporosis in a European multicenter clinical context.

Radiofrequency Echographic Multi Spectrometry (REMS) is a non-ionizing technology for the densitometric assessment of osteoporosis. It has already been validated in Italian women with respect to the current clinical reference technology, Dual-energy X-ray Absorptiometry (DXA). Aim of the current study was to assess the diagnostic accuracy of REMS technology with respect to DXA in a wider European clinical context. A total of 4307 female Caucasian patients aged between 30 and 90years underwent DXA and REMS scans at femoral neck and/or lumbar spine (the site depending on the medical prescription). The acquired data underwent a rigorous quality check in order to exclude the erroneous DXA and REMS reports. The diagnostic agreement between the two technologies was assessed, also stratifying for patients' age groups. The ability to recognise previously fractured patients was also investigated. Overall, 4245 lumbar spine scans and 4271 femoral neck scans were performed. The ability to discriminate patients with and without osteoporosis by femoral neck investigation resulted in sensitivity and specificity of 90.4% and 95.5%, respectively. For lumbar spine scans, a sensitivity of 90.9% and a specificity of 95.1% were obtained. The areas under the curve (AUCs) of the Receiver Operating Characteristic (ROC) curve evaluating the ability to discriminate groups of patients with previous osteoporotic fracture using DXA and REMS T-score values were 0.631 and 0.683 (p<0.0001), respectively, for femoral neck scans, whereas 0.603 and 0.640 (p=0.0002), respectively, for lumbar spine scans. The diagnostic effectiveness of REMS technology at reference anatomical sites for the assessment of osteoporosis has been confirmed in a large series of female patients, spanning from younger and pre-menopausal to elderly women up to 90years, in a multicenter European clinical context.

How to Interpret Dual Energy X-Ray Absorptiometry for Clinicians

Introduction: Dual energy X-ray absorptiometry (DXA) is a clinically proven method for measuring bone mineral density (BMD) in the lumbar spine, hip, femoral neck, and forearm. It is used for management and to monitor response of therapy of metabolic bone disease. Vertebral fracture assessment (VFA) is additional software that can be added to most DXA machines for the sole purpose of evaluating of occult fractures. DXA has excellent reproducibility, and emits low radiation dose (effective dose 1–3 mSv), which is equivalent to day-to-day background radiation. International Society for Clinical Densitometry (ISCD) recommends obtaining BMD of the posterolateral L1–L4, total hip, femoral neck, and distal one-third forearm.1 It is important for clinicians managing patients for metabolic bone disease to be able to review their own DXA images and reports to ensure the accuracy of the technical performance and interpretation. This is because DXA errors are not uncommon. One particular study of 354 DXA images reviewed showed 90% contained technical errors and 80% interpretation errors were found.2 ISCD has established guidelines for the best practice in DXA performance.3 Periodic quality assurance of DXA equipments should be performed by each center. Although most centers are knowledgeable, there still remains a gap in knowledge that affects interpretation. The aim of this video is to give a short review for clinicians on how to interpret BMD on their own and recognize pitfalls that can result in error in clinical decision making. Methods: A concise review of DXA images and reports is discussed. Results: A four-step approach on how clinicians can interpret their own DXA scan images is described in the video. The first step is to evaluate for proper positioning, review of edges placement, exclude artifacts such as lesions and calcifications if present, and confirm appropriate region-of-interest placement. By applying these four steps, clinicians can reduce potential errors that can lead to errors in medical management. In addition, clinical examples are given on how to monitor BMD changes overtime. This will require each institution to establish its margin of technical error known as precision error to determine its least significant change of each site (spine, total hip, femoral neck, and distal forearm). This allows clinicians to determine whether the change noted is clinically significant. The indications and interpretation of VFA are discussed.4 This is a lateral spine imaging to evaluate for fractures. This nicely augments DXA readings in those patients who are candidates for this VFA based on ISCD guidelines, which is discussed in this video. Conclusion: There are several quality measures needed to produce quality DXA images and reports. As clinicians, we should be empowered to be able to review our own DXA images and make appropriate clinical decisions regarding treatment. No competing financial interests exist. Runtime of video: 12 mins 52 secs

Consensus Statement by the American Association of Clinical Endocrinologists and American College of Endocrinology on the Quality of DXA Scans and Reports

High-quality dual-energy X-ray absorptiometry (DXA) scans are necessary for accurate diagnosis of osteoporosis and monitoring of therapy; however, DXA scan reports may contain errors that cause confusion about diagnosis and treatment. This American Association of Clinical Endocrinologists/American College of Endocrinology consensus statement was generated to draw attention to many common technical problems affecting DXA report conclusions and provide guidance on how to address them to ensure that patients receive appropriate osteoporosis care. The DXA Writing Committee developed a consensus based on discussion and evaluation of available literature related to osteoporosis and osteodensitometry. Technical errors may include errors in scan acquisition and/or analysis, leading to incorrect diagnosis and reporting of change over time. Although the International Society for Clinical Densitometry advocates training for technologists and medical interpreters to help eliminate these problems, many lack skill in this technology. Suspicion that reports are wrong arises when clinical history is not compatible with scan interpretation (e.g., dramatic increase/decrease in a short period of time; declines in previously stable bone density after years of treatment), when different scanners are used, or when inconsistent anatomic sites are used for monitoring the response to therapy. Understanding the concept of least significant change will minimize erroneous conclusions about changes in bone density. Clinicians must develop the skills to differentiate technical problems, which confound reports, from real biological changes. We recommend that clinicians review actual scan images and data, instead of relying solely on the impression of the report, to pinpoint errors and accurately interpret DXA scan images. AACE = American Association of Clinical Endocrinologists; BMC = bone mineral content; BMD = bone mineral density; DXA = dual-energy X-ray absorptiometry; ISCD = International Society for Clinical Densitometry; LSC = least significant change; TBS = trabecular bone score; WHO = World Health Organization.

High bone mass in adults

A finding of high bone mineral density (BMD) from routine dual-energy X-ray absorptiometry (DXA) screening is not uncommon. No consensus exists about the definition of high BMD, and T-score and/or Z-score cutoffs of ≥+2.5 or ≥+4 have been suggested. The many disorders that can result in high BMD are usually classified based on whether the BMD changes are focal vs. generalized or acquired vs. constitutional. In over half the cases, careful interpretation of the DXA report and images identifies the cause as an artefact (e.g., degenerative spinal disease, vascular calcifications, or syndesmophytes) or focal lesion (e.g., sclerotic bone metastasis or Paget's disease). Generalized acquired high BMD may be secondary to a diverse range of disorders such as fluorosis, diffuse bone sclerosis related to renal osteodystrophy, hematological diseases, and hepatitis C. Identification of the cause may require additional investigations such as imaging studies, serum tryptase assay, or serological tests for the hepatitis C virus. Finally, high BMD is a feature of many genetic diseases, most notably osteopetrosis and the disorders caused by mutations in the sclerostin gene SOST (sclerosing bone dysplasia and van Buchem disease) or in the LRP5 gene encoding the low-density lipoprotein receptor-related protein 5 (which is the Wnt co-receptor)

Electronic Medical Record Integration for Streamlined DXA Reporting.

Dual-energy X-ray absorptiometry (DXA) is the most frequently performed examination to assess bone mineral density in clinical practice. Aside from images and graphical displays, many numerical values are part of DXA reports. These values are typically manually entered into the formal report through the electronic medical record or PACS workstation. The process takes time and is prone to errors. Exporting the DXA numerical data via HL7 engine to the electronic medical record was proposed to improve reporting efficiency and accuracy. The output from the DXA unit computer was reconfigured to export the report content via the HL7 interface engine into the electronic medical record. Radiology interpretive reporting was subsequently done directly in the electronic medical record. In the evaluation of errors, 100 preliminary DXA reports before the change and 100 after the change were examined. These reports were analyzed for errors that included decimal change, number transposition, negative number issue, other incorrect number error, and failure to include prior exam for comparison. In addition, report turnaround times were evaluated before and after the changes were made. Reporting time evaluations included 1-year volume prior to change (3915 reports) and 1month post-change (206 reports). Of 100 DEXA exams before the change, 15 final reports contained 25 numerical errors. After the change, no numerical errors in the reports were identified. Exam end to final report time decreased from 2159 to 625min on average. Automating data transmittal from the DXA modality for report generation improves accuracy and turnaround time. This approach did not require any third party software, and healthcare information security concerns were negated since we are using our standard workstations. Secondary to the affordability and applicability to the large percentage of the population using electronic medical record systems, this type of automated workflow is recommended.

Effects of clinical reanalysis in dual energy X-ray absorptiometry reports.

This study aims to assess poor positioning rates of patients during X-ray and the accuracy of the analysis. In this study, we reanalyzed 323 dual energy X-ray absorptiometry (DXA) reports, by evaluating the scan images for proper patient positioning and scan analysis. We reviewed reports, according to a checklist prepared considering the proposals of Watts and The International Society for Clinical Densitometry official positions for 2013 (which were the same as in 2015). At least two remaining vertebrae were used to derive new bone mineral density and new T-scores. Positioning failures were found in 64.7% of the spine X-rays, 60.5% of the hip X-rays, and 83.9% of X-rays of both regions. A total of 112 (34.7%) spinal DXA images needed new T-score adjustments. T-scores and bone mineral density differed between the first reports and the clinician reanalysis (p<0.001). The error rate in DXA reports was higher than expected. Clinician analysis of DXA reports are important. To obtain a quality DXA report, all healthcare professionals should be trained and reminded about this topic.

Utilization and Reporting of Bone Densitometry: What Can the Musculoskeletal Radiologist Do to Help, Rather Than to Hurt?

Osteoporosis is a highly prevalent disease that predisposes patients to fragility fractures. These fractures carry serious risks, including increased mortality and the potential loss of functional independence. Effective treatments for osteoporosis are available, but these should be initiated before a fragility fracture actually occurs; to do so, osteoporosis must be diagnosed while it is still asymptomatic. The gold standard screening test used to detect low bone mass is dual-energy x-ray absorptiometry (DXA). Despite its clinical importance, the DXA report is sometimes neglected by radiologists-as though it were somehow less significant in diagnosis than our other modalities. If musculoskeletal radiologists are to help, rather than to hurt, we must raise the profile of this critical test with evidence-based utilization and coherent reporting: detailed recommendations for doing so are available from professional organizations such as the International Society for Clinical Densitometry and the National Osteoporosis Foundation. This brief survey will seek to remind the radiologist that a good densitometry report requires more than just copying numbers from a scanner.

Targeted assessment of fracture risk in women at midlife.

This study establishes a profile for women at midlife, referred for a dual energy X-ray absorptiometry (DXA), most likely to have osteoporosis, and from this, a pre-DXA screening tool has been developed. These findings inform much needed evidence-based guidelines for targeted and effective screening for osteoporosis and osteoporotic fracture prevention in women at midlife. There is no consensus as to whether women at midlife should undergo screening dual energy X-ray absorptiometry (DXA) to identify osteoporosis (T-score < -2.5). We investigated the prevalence of osteoporosis in women, aged 40-65 years, referred to 42 community-based Australian radiology centres, and identified the characteristics that best predict osteoporosis in women having a screening DXA. One thousand four hundred and two women completed the study questionnaire and had DXA reports available. After excluding women with an established indication for a DXA (58 %), users of bone-specific medication (10.5 %) and cancer (7.6 %), 466 women were classified as having a screening DXA. Forty of these women had osteoporosis at the lumbar spine (n = 32, 6.9 %) or femoral neck (n = 17, 3.6 %). Three predictors of osteoporosis (postmenopausal, nonuse of hormonal therapy and body mass index) were identified and incorporated into the Monash Osteoporosis Risk Score for women at midlife (MORS). In the screened study population, the MORS had a sensitivity of 70 % and specificity of 66 %, with a positive predictive value of 16.2 % and negative predictive value of 95.9 % for osteoporosis. Very few women referred for a screening DXA scan will be found to have osteoporosis. The MORS, a simple decision tool, would have identified 70 % of the women in our screening DXA study population and would have eliminated over 60 % of the screening DXA studies. Hence, use of the MORS may reduce unnecessary DXA scans and facilitate identification of the majority of cases of osteoporosis in women aged 40 to 65 years.

Impact of adding distal forearm DXA to hip and spine measurements on DXA report

Dual energy X-ray absorptiometry (DXA) is the gold standard modality for non-invasive diagnosis of osteoporosis but controversy exists about the optimal site (s) for bone mineral density (BMD) measurement. The objective was to find out impact of adding distal forearm BMD to hip and spine measurements on final diagnosis of a DXA study. This prospective study recruited 279 consecutive patients [female 256 (92%); male 23 (8%)] with a mean age of 63.25 ± 10.62 years from April 2011 to April 2012. The BMD was measured over hip (total hip and femoral neck), spine and distal forearm in all patients. Based on T-Score values of hip and spine (2 sites), diagnosis was normal in 34%, low bone mass in 40% and osteoporosis in 26% patients. However, adding distal forearm BMD and T-score (3 sites), diagnosis was normal in 28%, low bone mass in 37% and osteoporosis in 35%. Therefore, distal forearm BMD has upstaged the diagnosis from normal to low bone mass in 14%, from normal to osteoporosis in 2% and from low bone mass to osteoporosis in 18% patients. We conclude that combining distal forearm BMD with spine and hip can identify more patients with low bone mass or osteoporosis.

Incidental Findings with Dual-Energy X-Ray Absorptiometry: Spectrum of Possible Diagnoses

New dual-energy X-ray absorptiometry (DXA) technologies provide improved spatial resolution and high image quality. Our purpose was to review DXA examinations to detect collateral findings and to understand their potential impact on patient healthcare. We retrospectively and randomly reviewed 739 DXA examinations (191 of 739, 25.8%, whole body; 96 of 739, 13.0%, vertebral fracture assessment; 231 of 739, 31.3%, lumbar spine; 221 of 739, 29.9%, femur) that were performed in our institution with a new DXA equipment. Whenever an extra finding was discovered, the physician's report was read and the clinical history of the patient was investigated to understand whether that finding was already known, as well as to check the diagnosis. The population included 208 male and 531 female subjects (58±14years old). Incidental findings were detected in 117 (15.8%) of 739 DXA examinations (17 of 117, 14.5%, whole body; 41 of 117, 35.0%, vertebral fracture assessment; 32 of 117, 27.4%, lumbar spine; 27 of 117, 23.1%, femur): biliary and urinary stones (4.8%), vascular calcifications (33.7%), other soft tissue calcifications (25.3%-e.g., tendons, lymph nodes, intraparenchymatous calcifications), vertebral abnormalities (14.5%), other bone abnormalities (12.1%), and morphovolumetric alterations or abnormal anatomical structures (9.6%). Among all these findings, 50 (42.7%) of 117 could be verified by other imaging modalities. Forty-nine (98.0%) of 50 incidental findings were identified as true findings, and DXA was able to orient the diagnosis (exact diagnosis in 37 of 50, 74.0%); however, none of them was mentioned on available DXA reports. An interpreting physician should treat the DXA image with the same attention given to any other X-ray image. Sometimes DXA may allow a qualitative diagnosis of collateral findings. However, potential negative effects on healthcare economy should be considered for false-positive or insignificant findings.

Bone Mineral Density Assessment in a Multiple Sclerosis Population (P06.163)

Objective: To evaluate the prevalence of osteoporosis in a population of patients with Multiple Sclerosis (MS), and to assess the correlation of Bone Mineral Density (BMD) with demographic, clinical and treatment parameters. Background Osteoporosis and low BMD are common in MS. Possible explanations are attributed to factors such as lack of mobility, reduced vitamin D levels, chronic inflammatory state, steroidal and immunomodulatory treatments (DMTs). To date, available data do not allow to comprehensively define the profile of risk factors for osteoporosis in patients with MS. Design/Methods: As part of a project of «good clinical practice» in our centre, to all patients with MS aged ≥35 years, was offered the opportunity to carry out a BMD assessment by Dual energy X-ray Absorptiometry (DXA). Then we have retrospectively analyzed DXA reports, especially considering the diagnosis of osteoporosis, as well as evaluating the possible correlation of BMD with demographic, clinical and treatment parameters. Results: 112 agreed to partecipate, 96 with full available data. Sample mean age was 50.8 ± 7.2 y., 79% females, mean disease duration of 15.4 ± 8.8 y., and mean EDSS score of 3.0 ± 2.0. Osteoporosis was found in 16.7% of the patients; mean vertebral and femoral BMD scores were respectively of .93 ± .13,and .82 ± .14. As expected, patients with either vertebral (p =. 02) or femoral (p =. 025) osteoporosis were older, while those with only femoral osteoporosis had a higher EDSS score (p Conclusions: The prevalence of osteoporosis was comparable with previous reports. As in the general population BMD correlated with age, while femoral BMD strongly correlated with disability. No correlation was found with the use of steroid therapy or DMTs. Disclosure: Dr. Haggiag has nothing to disclose. Dr. Mercurio has nothing to disclose. Dr. Bray has nothing to disclose. Dr. Haggiag has nothing to disclose. Dr. Gasperini has received personal compensation for activities with Merck Serono, Bayer Pharmaceuticals Corporation, Biogen Idec, Sanofi-Aventis Pharmaceuticals, Inc. as a speaker. Dr. Galgani has nothing to disclose.

Pediatric dual-energy X-ray absorptiometry: interpretation and clinical and research application

= Abstract = Peak bone mass is established predominately during childhood and adolescence. It is an important determinant of future resistance to osteoporosis and fractures to gain bone mass during growth. The issue of low bone density in children and adolescents has recently attracted much attention and the use of pediatric dual-energy X-ray absorptiometry (DXA) is increasing. The process of interpretation of pediatric DXA results is different from that of adults because normal bone mineral density (BMD) of children varies by age, body size, pubertal stage, skeletal maturation, sex, and ethnicity. Thus, an appropriate normal BMD Z-score reference value with Z-score should be used to detect and manage low BMD. Z-scores below -2.0 are generally considered a low BMD to pediatrician even though diagnoses of osteoporosis in children and adolescents are usually only made in the presence of at least one fragility fracture. This article will review the basic knowledge and practical guidelines on pediatric DXA based on the International Society for Clinical Densitometry (ISCD) Pediatric Official Positions. Also discussed are the characteristics of normal Korean children and adolescents with respect to BMD development. The objective of this review is to help pediatricians to understand when DXA will be useful and how to interpret pediatric DXA reports in the clinical practice for management of children with the potential to develop osteoporosis in adulthood. (Korean J Pediatr 2010;53:286-293)

Evaluation of the patient positioning during DXA measurements in daily clinical practice

For prompt diagnosis of osteoporosis, properly instructed dual-energy X-ray absorptiometry (DXA) measurements are required. To get correct DXA results in addition to quality control procedures, proper positioning of specific body regions such as hip and spine should also be achieved. The aim of this study was to assess the accurateness of the patient positioning for hip and spine regions in daily clinical practice. Hip and spine scan images of 113 DXA reports were evaluated for whether or not the patient was positioned correctly. Out of 113 hip and spine DXA reports, 61 hips and 94 spines were found to have scan images with improper positions. The spine was not straight in 48.7% of the images. The 38.9% of the spinal images did not comprise both iliac crests, and 40.7% did not include T12 and L5 vertebrae. In hip DXA reports, 40.7% of the femoral shaft was deviated to one side. We found the ratio of invalid positions surprisingly very high. Although this may stem from local technical problems and may not reflect the overall quality of scans in other centers, such misinterpretations would definitely affect clinicians' decisions in an inappropriate way. We suggest that relevant inconveniences should be kept in mind both by the clinicians and the technical staff for better production and prompt estimation of DXA measurements.

Minimal error in self-report of having had DXA, but self-report of its results was poor

Objective To examine the validity of both self-report of having had dual-energy x-ray absorptiometry (DXA) and self-reported DXA test results. Methods Participants were recruited in 2003 and 2004 from a population-based study of women aged 65–90 years examining osteoporosis management in Ontario, Canada ( N = 871). Women reporting having had a DXA were eligible and asked to report the results of their most recent test. Participant responses were compared against DXA reports obtained from physicians. Results We obtained 413 (81%) physician records among the 510 women who reported having had a DXA test. Of these, the positive predictive value for self-report of having had a DXA was 93%. The weighted kappa statistic for the agreement between self-report and actual DXA results was 0.42 (95% confidence interval = 0.34–0.49). Although 84% of those with normal bone reported this, only 29% of those with osteopenia and 62% with osteoporosis reported their results correctly. Self-report of a clinical diagnosis of osteoporosis was better among those with a low trauma fracture, yet underestimated osteoporosis prevalence by 24%. Conclusion There is minimal measurement error in self-report of having had a DXA test. Self-report of DXA results will underestimate osteoporosis prevalence and is not a good proxy for clinical diagnosis.