scholarly journals Assessment of Myosteatosis on Computed Tomography by Automatic Generation of a Muscle Quality Map Using a Web-Based Toolkit: Feasibility Study (Preprint)

2020 ◽  
Author(s):  
Dong Wook Kim ◽  
Kyung Won Kim ◽  
Yousun Ko ◽  
Taeyong Park ◽  
Seungwoo Khang ◽  
...  

BACKGROUND Muscle quality is associated with fatty degeneration or infiltration of the muscle, which may be associated with decreased muscle function and increased disability. OBJECTIVE The aim of this study is to evaluate the feasibility of automated quantitative measurements of the skeletal muscle on computed tomography (CT) images to assess normal-attenuation muscle and myosteatosis. METHODS We developed a web-based toolkit to generate a muscle quality map by categorizing muscle components. First, automatic segmentation of the total abdominal muscle area (TAMA), visceral fat area, and subcutaneous fat area was performed using a predeveloped deep learning model on a single axial CT image at the L3 vertebral level. Second, the Hounsfield unit of each pixel in the TAMA was measured and categorized into 3 components: normal-attenuation muscle area (NAMA), low-attenuation muscle area (LAMA), and inter/intramuscular adipose tissue (IMAT) area. The myosteatosis area was derived by adding the LAMA and IMAT area. We tested the feasibility of the toolkit using randomly selected healthy participants, comprising 6 different age groups (20 to 79 years). With stratification by sex, these indices were compared between age groups using 1-way analysis of variance (ANOVA). Correlations between the myosteatosis area or muscle densities and fat areas were analyzed using Pearson correlation coefficient r. RESULTS A total of 240 healthy participants (135 men and 105 women) with 40 participants per age group were included in the study. In the 1-way ANOVA, the NAMA, LAMA, and IMAT were significantly different between the age groups in both male and female participants (<i>P</i>≤.004), whereas the TAMA showed a significant difference only in male participants (male, <i>P</i>&lt;.001; female, <i>P</i>=.88). The myosteatosis area had a strong negative correlation with muscle densities (<i>r</i>=–0.833 to –0.894), a moderate positive correlation with visceral fat areas (<i>r</i>=0.607 to 0.669), and a weak positive correlation with the subcutaneous fat areas (<i>r</i>=0.305 to 0.441). CONCLUSIONS The automated web-based toolkit is feasible and enables quantitative CT assessment of myosteatosis, which can be a potential quantitative biomarker for evaluating structural and functional changes brought on by aging in the skeletal muscle. CLINICALTRIAL

10.2196/23049 ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. e23049
Author(s):  
Dong Wook Kim ◽  
Kyung Won Kim ◽  
Yousun Ko ◽  
Taeyong Park ◽  
Seungwoo Khang ◽  
...  

Background Muscle quality is associated with fatty degeneration or infiltration of the muscle, which may be associated with decreased muscle function and increased disability. Objective The aim of this study is to evaluate the feasibility of automated quantitative measurements of the skeletal muscle on computed tomography (CT) images to assess normal-attenuation muscle and myosteatosis. Methods We developed a web-based toolkit to generate a muscle quality map by categorizing muscle components. First, automatic segmentation of the total abdominal muscle area (TAMA), visceral fat area, and subcutaneous fat area was performed using a predeveloped deep learning model on a single axial CT image at the L3 vertebral level. Second, the Hounsfield unit of each pixel in the TAMA was measured and categorized into 3 components: normal-attenuation muscle area (NAMA), low-attenuation muscle area (LAMA), and inter/intramuscular adipose tissue (IMAT) area. The myosteatosis area was derived by adding the LAMA and IMAT area. We tested the feasibility of the toolkit using randomly selected healthy participants, comprising 6 different age groups (20 to 79 years). With stratification by sex, these indices were compared between age groups using 1-way analysis of variance (ANOVA). Correlations between the myosteatosis area or muscle densities and fat areas were analyzed using Pearson correlation coefficient r. Results A total of 240 healthy participants (135 men and 105 women) with 40 participants per age group were included in the study. In the 1-way ANOVA, the NAMA, LAMA, and IMAT were significantly different between the age groups in both male and female participants (P≤.004), whereas the TAMA showed a significant difference only in male participants (male, P<.001; female, P=.88). The myosteatosis area had a strong negative correlation with muscle densities (r=–0.833 to –0.894), a moderate positive correlation with visceral fat areas (r=0.607 to 0.669), and a weak positive correlation with the subcutaneous fat areas (r=0.305 to 0.441). Conclusions The automated web-based toolkit is feasible and enables quantitative CT assessment of myosteatosis, which can be a potential quantitative biomarker for evaluating structural and functional changes brought on by aging in the skeletal muscle.


Author(s):  
Min Jung Lee ◽  
Hong-Kyu Kim ◽  
Eun Hee Kim ◽  
Sung Jin Bae ◽  
Kyung Won Kim ◽  
...  

Objective: Low muscle mass was known to be associated with cardiovascular diseases. However, only few studies investigated the association between muscle quality and subclinical coronary atherosclerosis. Thus, we evaluated whether muscle quality measured by abdominal computed tomography is associated with the risk of coronary artery calcification. Approach and Results: We conducted a cross-sectional study on 4068 subjects without cardiovascular disease who underwent abdominal and coronary computed tomography between 2012 and 2013 during health examinations. The cross-sectional area of the skeletal muscle was measured at the L3 level (total abdominal muscle area, total abdominal muscle area) and segmented into normal attenuation muscle area, low attenuation muscle area, and intramuscular adipose tissue. We calculated the normal attenuation muscle area/total abdominal muscle area index, of which a higher value reflected a higher proportion of good quality muscle (normal attenuation muscle area) and a lower proportion of myosteatosis (low attenuation muscle area and intramuscular adipose tissue). In women, as the normal attenuation muscle area/total abdominal muscle area quartiles increased, the odds ratios (95% CIs) for significant coronary artery calcification (>100) consistently decreased (0.44 [0.24–0.80], 0.39 [0.19–0.81], 0.34 [0.12–0.98]; P =0.003) after adjusting for cardiovascular risk factors including visceral fat area and insulin resistance. In men, the odds ratios in the Q2 group were significantly lower than those in the Q1, but the association was attenuated in Q3–4 after adjustment. Conclusions: A higher proportion of good quality muscle was strongly associated with a lower prevalence of significant coronary artery calcification after adjustment, especially in women. Poor skeletal muscle quality may be an important risk factor for subclinical coronary atherosclerosis.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Anton Faron ◽  
Stefan Kreyer ◽  
Alois M. Sprinkart ◽  
Thomas Muders ◽  
Stefan F. Ehrentraut ◽  
...  

AbstractImpaired skeletal muscle quality is a major risk factor for adverse outcomes in acute respiratory failure. However, conventional methods for skeletal muscle assessment are inapplicable in the critical care setting. This study aimed to determine the prognostic value of computed tomography (CT) fatty muscle fraction (FMF) as a biomarker of muscle quality in patients undergoing extracorporeal membrane oxygenation (ECMO). To calculate FMF, paraspinal skeletal muscle area was obtained from clinical CT and separated into areas of fatty and lean muscle based on densitometric thresholds. The cohort was binarized according to median FMF. Patients with high FMF displayed significantly increased 1-year mortality (72.7% versus 55.8%, P = 0.036) on Kaplan–Meier analysis. A multivariable logistic regression model was built to test the impact of FMF on outcome. FMF was identified as a significant predictor of 1-year mortality (hazard ratio per percent FMF, 1.017 [95% confidence interval, 1.002–1.033]; P = 0.031), independent of anthropometric characteristics, Charlson Comorbidity Index, Simplified Acute Physiology Score, Respiratory Extracorporeal Membrane Oxygenation Survival Prediction Score, and duration of ECMO support. To conclude, FMF predicted 1-year mortality independently of established clinical prognosticators in ECMO patients and may have the potential to become a new muscle quality imaging biomarker, which is available from clinical CT.


2003 ◽  
Vol 149 (6) ◽  
pp. 543-548 ◽  
Author(s):  
AG Rockall ◽  
SA Sohaib ◽  
D Evans ◽  
G Kaltsas ◽  
AM Isidori ◽  
...  

OBJECTIVE: Hepatic steatosis may occur in association with insulin resistance and obesity, two features commonly seen in Cushing's syndrome (CS). The aim of this report is to assess the prevalence of hepatic steatosis in patients with active CS using computed tomography (CT) and to identify any associations between hepatic steatosis, endocrine and biochemical variables and body fat distribution. PATIENTS AND MEASUREMENTS: We identified 50 patients with active CS in whom appropriate CT was available to allow measurement of liver and spleen attenuation. In 26 patients, abdominal fat measurements were also available. Serum markers of CS and liver function tests were recorded. RESULTS: Ten of 50 patients had a liver-to-spleen CT attenuation ratio (L/S) of less than 1, indicating hepatic steatosis. There was a significant negative correlation between both liver attenuation and L/S ratio with total abdominal fat area, visceral fat area, the percentage of visceral fat and the visceral to subcutaneous fat ratio; the strongest negative correlation was found between visceral fat area and L/S ratio (r=-0.638, P<0.001, n=26). L/S ratio positively correlated with alkaline phosphatase levels (r=+0.423, P=0.044, n=23) but with no other serum marker of CS activity or liver enzyme. CONCLUSIONS: We have demonstrated hepatic steatosis on CT in 20% of patients with active CS. The presence of hepatic steatosis was significantly correlated with total abdominal fat area and visceral fat area.


2021 ◽  
Author(s):  
Danae Delivanis ◽  
Maria Daniela Hurtado Andrade ◽  
Tiffany Cortes ◽  
Shobana Athimulam ◽  
Aakanksha Khanna ◽  
...  

Objective: Increased visceral fat and sarcopenia are cardiovascular risk factors that may explain increased cardiovascular morbidity and frailty in patients with adrenal adenomas. Our objective was to compare body composition measurement of patients with adrenal adenomas to referent subjects without adrenal disease Design: Cross-sectional study, 2014-2018 Methods: Participants were adults with nonfunctioning adrenal tumor (NFAT), mild autonomous cortisol secretion (MACS) and Cushing syndrome (CS), and age, sex and body mass index 1:1 matched referent subjects without adrenal disorders. Main outcome measures were body composition measurements calculated from abdominal computed tomography imaging. Intraabdominal adipose tissue and muscle mass measurements were performed at the 3rd lumbar spine level. Results: Of 227 patients with adrenal adenomas, 20 were diagnosed with CS, 76 with MACS and 131 with NFAT. Median age was 56 years (range, 18-89), and 67% were women. When compared to referent subjects, patients with CS, MACS, and NFAT demonstrated a higher visceral fat (odds ratio (OR) of 2.2 [95% CI 0.9-6.5], 2.0 [1.3-3.2], and 1.8 [1.2-2.7] and a lower skeletal muscle area (OR of 0.01 [95% CI 0-0.09], 0.31 [0.18-0.49], and 0.3 [1.2-2.7]), respectively. For every 1 mcg/dL cortisol increase after overnight dexamethasone, visceral fat/muscle area ratio increased by 2.3 (P=0.02) and mean total skeletal muscle area decreased by 2.2cm2 (P=0.03). Conclusion: Patients with adrenal adenomas demonstrate a lower muscle mass and a higher proportion of visceral fat when compared to referent subjects, including patients with NFAT. Even a subtle abnormality in cortisol secretion may impact health of patients with adenomas.


2005 ◽  
Vol 99 (3) ◽  
pp. 1220-1225 ◽  
Author(s):  
SoJung Lee ◽  
Jennifer L. Kuk ◽  
Lance E. Davidson ◽  
Robert Hudson ◽  
Katherine Kilpatrick ◽  
...  

It is unclear whether chronic exercise without caloric restriction or weight loss is a useful strategy for obesity reduction in obese men with and without Type 2 diabetes (T2D). We examined the effects of exercise without weight loss on total and regional adiposity and skeletal muscle mass and composition in lean men and in obese men with and without T2D. Twenty-four men participated in 13 wk of supervised aerobic exercise, five times per week for 60 min at a moderate intensity (∼60% peak oxygen uptake). Total and regional body composition was measured by magnetic resonance imaging. Skeletal muscle composition was determined using computed tomography. Cardiorespiratory fitness was assessed using a graded maximal treadmill test. Body weight did not change within any group in response to exercise ( P > 0.1). Significant reductions in total, abdominal subcutaneous, and visceral fat were observed within each group ( P < 0.01). The reduction in total and abdominal subcutaneous fat was not different ( P > 0.1) between groups; however, the reduction in visceral fat was greater ( P < 0.01) in the obese and T2D groups by comparison to the lean group. A significant ( P < 0.01) increase in total skeletal muscle, high-density muscle area, and mean muscle attenuation was observed independent of group, and these changes were not different between groups ( P > 0.1). Accordingly, whole body fat-to-muscle ratio was increased ( P < 0.01) independent of groups. In conclusion, regular exercise without weight loss is associated with a substantial reduction in total and visceral fat and in skeletal muscle lipid in both obesity and T2D.


2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e15134-e15134
Author(s):  
Deborah Mukherji ◽  
Carmel Jo Pezaro ◽  
Diletta Bianchini ◽  
Nina Tunariu ◽  
Amy Mulick Cassidy ◽  
...  

e15134 Background: Sarcopenia, or skeletal muscle wasting, is an independent prognostic factor in advanced malignancy (Prado Lancet Onc 2008). Decreased muscle and increased fat are recognized side effects of androgen deprivation therapy. AA is a CYP17 inhibitor administered with corticosteroids (C), approved for treatment of advanced CRPC. AA reduces circulating androgens to ‘super-castrate’ levels; we hypothesized that AA + C would impact body composition. Methods: We retrospectively evaluated 54 CRPC pts treated on a Phase I/II trial. Pts received AA alone followed by combination AA + C on biochemical progression. CT scans at baseline, on AA alone and on AA + C were analyzed. Cross-sectional areas of fat and muscle were measured on 3 consecutive images at L4 using OsiriX 4.0. Muscle area was used to calculate skeletal muscle index (SMI); sarcopenia was defined as SMI <52.4 cm2/m2. Data were analyzed using t-tests and Kaplan-Meier analysis with overall survival (OS) measured from day 1 of AA. Results: Median duration on AA alone was 7.4 months (m; range 1.4-37.5); median duration on concurrent AA + C was 7.4m (range 0.9-46.2). Body composition did not change between two pre-treatment scans (n=29; median 3m apart). On AA alone there was a decrease in total fat (-8.5%, p=0.0001), visceral fat (-9.8%, p=0.0015) and muscle mass (-3.9%, p=0.0023) with a significant decrease in mean body mass index (BMI; -3.4 %, p=0.0118). Conversely AA + C was associated with increased total fat (+15.1%, p<0.0001) and visceral fat (+21.4%, p<0.0001) but no further change in muscle mass. Mean BMI significantly increased on the addition of C, returning to baseline levels (p< 0.0001). Overall, 13 pts (24%) were sarcopenic prior to commencing AA compared to 22 (41%) at the end of treatment. Pts who were sarcopenic at baseline had significantly reduced OS: 26.1m (95%CI 16.6 – 41) vs 46.5m (95%CI 28.6 – 57.5, p=0.0253). Conclusions: Treatment with AA alone resulted in decreased fat and muscle. AA + C increased body fat without further alteration in muscle mass. Changes in BMI did not reflect changes in body composition. Sarcopenia at baseline was a negative prognostic factor in this population.


Sign in / Sign up

Export Citation Format

Share Document