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Dietetics and Nutrition in Oncology Patients: Evaluation of Nutritional Status, Weight Control, and Nutrigenomics
Published in Paloma Tejero, Hernán Pinto, Aesthetic Treatments for the Oncology Patient, 2020
Dual-energy x-ray absorptiometry (DEXA) is the reference technique in clinical practice. DEXA is primarily used for measurements of bone mineral content (hormonal blockages performed in some tumors and chronic use of corticosteroids directly affect bone mass). Total body DEXA scans can also accurately measure fat mass and lean mass (or free fat mass), both at the total body as well as at segmentary levels. DEXA does expose the patient and operator to ionizing radiation, but the dose is very small to both. The main limitations of DEXA are the cost and technical expertise [30,31].
Breast Surgery
Published in Tjun Tang, Elizabeth O'Riordan, Stewart Walsh, Cracking the Intercollegiate General Surgery FRCS Viva, 2020
Gaural Patel, Lucy Kate Satherley, Animesh JK Patel, Georgina SA Phillips
What other factors should be considered when starting a patient on endocrine manipulation?Patients commencing on an AI should have a baseline DEXA scan.Advise patients about the side-effect profile of these agents:Tamoxifen: menopausal symptoms Endometrial hyperplasia/risk of cancerRisk of deep venous thromboembolismReduced cognition, reduced libidoBenefit: increased bone density due to agonist actionAIs: menopausal symptoms Bone density lossJoint symptomsRarely, liver and renal dysfunction, adrenal insufficiency
Clinical Perspective on Dual Energy Computed Tomography
Published in Katsuyuki Taguchi, Ira Blevis, Krzysztof Iniewski, Spectral, Photon Counting Computed Tomography, 2020
Charis McNabney, Shamir Rai, Darra T. Murphy
Pilot studies have indicated potential for DECT arthrography (to evaluate joints); however, larger patient trials and refinement of post-processing techniques are required to prove clinical efficacy. Similarly, DECT's use in the detection and follow-up of metastases requires further validation, particularly with respect to presentation of different tumor types and normal variants. DEXA scanning is considered the reference standard for assessment of osteoporosis; however, there are many reported limitations to this technique. A three-dimensional approach can help overcome some of these limitations. DECT with bone mineral density application represents a promising three-dimensional approach in the assessment of osteoporosis, with reduced radiation dose when compared to conventional CT (Mallinson et al. 2016).
The effect of shock waves on mineralization and regeneration of distraction zone in osteoporotic rabbits
Published in Annals of Medicine, 2023
Enes Özkan, Erman Şenel, Mehmet Cihan Bereket, Mehmet Emin Önger
DEXA is a reliable diagnostic method that is commonly used to estimate fracture risk by determining the bone mineral density in osteoporosis patients [15]. According to the results of the DEXA examination, lower BMD values were detected in the osteoporotic control group compared to the healthy control group, as expected. Yet interestingly, although higher new bone formation was observed in both ESWT groups, BMD values were observed to be lower in both the early (DEXA1) and late periods (DEXA2) compared to the O-Cont group. In our previous study in which we examined the effect of ESWT on distraction osteogenesis in healthy rabbits, we found lower BMD and bone mineral content values in the ESWT groups compared to the control groups [24]. One reason may be that immature bone is seen more frequently in the early period and the early radiological findings are insufficient due to the lack of mineralization of this bone [25]. Another reason is that ESWT may have increased osteoclastic activity. However, studies have shown that ESWT increases osteoblastic and osteoclastic gene markers, but the osteoclastic effect is short-term and temporary [29]. Therefore, the first reason stated appears to be more likely.
Heart failure is associated with accelerated age related metabolic bone disease
Published in Acta Cardiologica, 2021
Pieter Martens, Jozine M. ter Maaten, Dimitri Vanhaen, Ellen Heeren, Thalissa Caers, Becky Bovens, Jeroen Dauw, Matthias Dupont, Wilfried Mullens
Bone densitometry measurements were performed using dual-energy X-ray absorptiometry via a GE Lunar Prodigy Advance scanner (Madison, WI, USA). The DEXA-scan is the gold standard for measuring bone mineral mass and density in a non-invasive way, with minimal exposure to ionising radiation. Bone mineral density was measured at the level of the lumbar spine segment L1–L4 and the femur. The bone mineral density was calculated as the amount of total bone calcium (in gram) per measured area (cm2) generating an unit expressed in g/cm2. Additionally, bone mineral density was expressed by T- and Z-scores. The T-score represents the difference in bone mineral density in comparison with young healthy individuals and is expressed in standard deviations (SD). A T-score of –1.0 SD or higher is considered normal. T-scores between –1.0 and –2.5 SD indicate osteopenia, while values less than –2.5 indicate osteoporosis. The Z-scores represents the difference in BMD in comparison to healthy aged matched individuals and is also expressed in SD.
Preoperative BMD does not influence femoral stem subsidence of uncemented THA when the femoral T-score is > –2.5
Published in Acta Orthopaedica, 2021
Karen Dyreborg, Michala S Sørensen, Gunnar Flivik, Søren Solgaard, Michael M Petersen
DEXA scans were performed before surgery at the Department of Orthopaedic Surgery, Rigshospitalet, Denmark. The hips to be operated on were first scanned using the research scan option, starting from the level of the acetabulum and ending 25 cm distally. Sandbags secured stable and neutral rotation of the leg. Additionally, we made a preoperative standardized osteoporosis scan of the hip, with calculation of BMD of the femoral neck and the corresponding T- and Z-scores (normal population: Fem Neck Caucasian Copenhagen 93 v 2.3) (Figure 2). For these scans we used the manufacturer’s special fixation device to fixate the pelvis and lower limbs to ensure a reproducible hip BMD measurement. The results of these scans were not used to exclude any patient for inclusion in the RSA study.