Comparison of computed tomography and dual-energy X-ray absorptiometry in the evaluation of body composition in patients with obesity

Abstract

Objectivea) To evaluate the accuracy of the pre-existing equations (based on cm2 provided by CT images), to estimate in kilograms (Kg) the body composition (BC) in patients with obesity (PwO), by comparison with Dual-energy X-ray absorptiometry (DXA). b) To evaluate the accuracy of a new approach (based on both cm2 and Hounsfield Unit parameters provided by CT images), using an automatic software and artificial intelligence to estimate the BC in PwO, by comparison with DXA.MethodsSingle-centre cross-sectional study including consecutive PwO, matched by gender with subjects with normal BMI. All the subjects underwent BC assessment by Dual-energy X-ray absorptiometry (DXA) and skeletal-CT at L3 vertebrae. CT images were processed using FocusedON-BC software. Three different models were tested. Model 1 and 2, based on the already existing equations, estimate the BC in Kg based on the tissue area (cm2) in the CT images. Model 3, developed in this study, includes as additional variables, the tissue percentage and its average Hounsfield unit.Results70 subjects (46 PwO and 24 with normal BMI) were recruited. Significant correlations for BC were obtained between the three models and DXA. Model 3 showed the strongest correlation with DXA (r= 0.926, CI95% [0.835-0.968], p<0.001) as well as the best agreement based on Bland – Altman plots.ConclusionThis is the first study showing that the BC assessment based on skeletal CT images analyzed by automatic software coupled with artificial intelligence, is accurate in PwO, by comparison with DXA. Furthermore, we propose a new equation that estimates both the tissue quantity and quality, that showed higher accuracy compared with those currently used, both in PwO and subjects with normal BMI.

Body composition assessment with ultrasound muscle measurement: optimization through the use of semi-automated tools in colorectal cancer

“…Tissue quality was assessed based on its average Hounsfield Units (HU) value. Standard thresholds were used as follows: −29 to 150 HU for skeletal muscle, −190 to−30 for subcutaneous adipose tissue and−150 to−50 for visceral adipose tissue ( 41 , 42 , 47 ).…”

Diagnostics of the body composition of an elderly person to assess the prognosis of his health

“…В одноцентровом перекрестном исследовании, выполненном Palmas F. et al (2023), оценивали точность автоматического программного обеспечения и искусственного интеллекта для анализа CT в диагностике ожирения, по сравнению с DXA, принятым за эталон. Всем пациентам (46 человек с ожирением и 24 -с нормальным ИМТ) была проведена оценка состава тела с помощью DXA и CT на уровне L3.…”

“…В результате, между тремя моделями и DXA были получены значимые корреляции. Модель 3 показала самую сильную корреляцию с DXA (r= 0,926; ДИ 95%: 0,835-0,968; р<0,001), а также наилучшее согласие, основанное на графиках Бланда-Альтмана [47].…”

Prospective Study to Evaluate Rectus Femoris Muscle Ultrasound for Body Composition Analysis in Patients Undergoing Bariatric Surgery

“…Currently, body mass index (BMI) continues to serve as a categorical diagnostic measure for obesity. However, BMI has notable drawbacks as it does not offer insights into body composition (BC) or the metabolic status of individuals [4,5]. In this way, new methods, as muscle ultrasound (MUS), should be introduced into clinical practice to assess the BC of these patients, especially if they are candidates for bariatric surgery (BS), since weight loss caused by BS leads to changes in the BC.…”

“…Nonetheless, DEXA lacks the ability to provide information about specific muscle groups, thus failing to address regional sarcopenia. Additionally, accessibility to DEXA is limited in many clinics, and it is not routinely performed except for bone density assessment [5,13,14]. Among the numerous methods available for assessing muscle mass, MUS is becoming increasingly recognized as a valuable tool in clinical settings, being a simple, real-time, noninvasive, radiationfree, low-cost, and easily transportable technique.…”