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The American Journal of Clinical... Jun 2005The influence of age and sex on the distribution of abdominal adipose tissue for a given waist circumference (WC) is unclear. (Comparative Study)
Comparative Study
BACKGROUND
The influence of age and sex on the distribution of abdominal adipose tissue for a given waist circumference (WC) is unclear.
OBJECTIVE
The objective was to investigate the influence of age and sex on total (TAAT), visceral (VAT), and abdominal subcutaneous (ASAT) adipose tissue for a given WC.
DESIGN
Body composition was assessed by whole-body magnetic resonance imaging in 147 younger men (< 50 y), 83 older men, 171 younger (premenopausal) women, and 80 older (postmenopausal) women with a wide range (16-40; in kg/m(2)) of body mass indexes.
RESULTS
Within each sex, the regression lines between WC and TAAT were not significantly different (P > 0.1) between younger and older groups. Collapsed across age groups, women had more TAAT for a given WC than did men; however, this difference was significantly reduced with increasing WC (P < 0.05). Within each sex, regression lines derived for WC and ASAT were not significantly different between younger and older groups (P > 0.1). Collapsed across age groups, women had 1.8 kg more ASAT for a given WC (P < 0.05) than did men across the range of WCs. Within each sex, older men and women had a significantly greater increase in VAT for a given WC (P < 0.05) than did younger men and women. Furthermore, independent of age group, the slopes for WC and VAT were significantly higher (P < 0.05) in men than in women.
CONCLUSIONS
There are significant sex differences in TAAT, VAT, and ASAT for a given WC. Furthermore, the relation between WC and VAT is substantially influenced by age.
Topics: Abdomen; Adipose Tissue; Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Aging; Body Composition; Body Constitution; Body Mass Index; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Sex Characteristics; Sex Factors; Viscera; Waist-Hip Ratio
PubMed: 15941883
DOI: 10.1093/ajcn/81.6.1330 -
European Radiology Sep 2022The aim of this study was to evaluate whether simple 2D measurements in axial slices of head and neck CT examinations correlate with generally established measurements...
OBJECTIVES
The aim of this study was to evaluate whether simple 2D measurements in axial slices of head and neck CT examinations correlate with generally established measurements of body composition in abdominal CT at the height of the third lumbar vertebra and thus allow for an estimation of muscle and fat masses.
METHODS
One hundred twenty-two patients who underwent concurrent CT of the head and neck and the abdomen between July 2016 and July 2020 were retrospectively included. For a subset of 30 patients, additional bioelectrical impedance analysis (BIA) was available. Areas of paraspinal muscles at the height of the third (C3) and fifth cervical vertebrae (C5) as well as the total cross-sectional area at the height of C3 and at the submandibular level were correlated with the results of abdominal measurements and BIA. Furthermore, intra- and interreader variabilities of all measurements were assessed.
RESULTS
Regarding adipose tissue, good correlations were found between the total cross-sectional area of the patient's body at the submandibular level and at the height of C3 between both abdominal measurements and BIA results (r = 0.8-0.92; all p < 0.001). Regarding muscle, the total paraspinal muscle area at the height of C3 and C5 showed strong correlations with abdominal measurements and moderate to strong correlations with BIA results (r = 0.44-0.80; all p < 0.001), with the muscle area on C5 yielding slightly higher correlations.
CONCLUSIONS
Body composition information can be obtained with comparable reliability from head and neck CT using simple biplanar measurements as from abdominal CT.
KEY POINTS
• The total paraspinal muscle area at the height of C3 and C5 correlates strongly with abdominal muscle mass. • The total cross-sectional area at the submandibular level and at the height of C3 shows good correlations with abdominal fat mass. • The described measurements facilitate a rapid, opportunistic assessment of relevant body composition parameters.
Topics: Abdomen; Body Composition; Electric Impedance; Humans; Muscle, Skeletal; Reproducibility of Results; Retrospective Studies; Tomography, X-Ray Computed
PubMed: 35389049
DOI: 10.1007/s00330-022-08773-9 -
European Journal of Radiology Sep 2022To evaluate the use of ultrasonography (US) as an alternative to dual-energy x-ray absorptiometry (DXA) to predict the percentage ratio of android/gynoid (A/G) fat mass.
OBJECTIVE
To evaluate the use of ultrasonography (US) as an alternative to dual-energy x-ray absorptiometry (DXA) to predict the percentage ratio of android/gynoid (A/G) fat mass.
METHODS
This was a cross-sectional study. Twenty-eight participants included in the study underwent whole-body DXA examinations and the A/G ratio was calculated. Soft-tissue US was performed in several standardised anthropometric areas of the body. Correlation analysis between abdominal and gluteal-femoral fat thickness based on US and A/G ratio was conducted using the Pearson or Spearman test depending on the data normality. Multiple regression analysis using the backward stepwise method was performed to establish an equation for estimating the A/G ratio.
RESULTS
There was a strong and significant correlation between fat thickness in the six anthropometric areas and the A/G ratio in female participants. The analysis revealed three anthropometric areas: upper abdomen (S4), lower abdomen (S5), and mid-xiphoid-umbilical region (S7), that can accurately predict the A/G ratio by 82.3%. (P < 0.05). However, no such correlation was found in male participants.
CONCLUSIONS
US measurement of fat thickness can predict A/G ratio in the female population. However, this method is not recommended for men.
Topics: Abdomen; Absorptiometry, Photon; Adipose Tissue; Body Composition; Body Mass Index; Cross-Sectional Studies; Female; Humans; Male; Obesity
PubMed: 35660916
DOI: 10.1016/j.ejrad.2022.110387 -
BMC Veterinary Research Jan 2019Computed tomography (CT) has been used to estimate body composition and determine tissue distribution in dogs, despite limited validation. This may introduce error into...
BACKGROUND
Computed tomography (CT) has been used to estimate body composition and determine tissue distribution in dogs, despite limited validation. This may introduce error into estimates of body composition studies and its effect on health in dogs. Further, the modality has not been validated against dual-energy X-ray absorptiometry (DXA) or over a wide range of dog breeds, ages and sexes. The objective of this study was to validate the use of semi-automated, abdominal volume CT for estimating total body composition of dogs relative to DXA. Twenty-two staff-owned dogs (weighing between 5.1-60 kg) were sedated and underwent full body DXA scan and abdominal CT. Abdominal tissue composition was estimated by CT using semi-automated volume segmentation, over predetermined tissue Hounsfield threshold values. Abdominal tissue composition determined by the various CT threshold ranges was compared to total body composition determined by DXA.
RESULTS
Abdominal tissue composition estimated by CT strongly correlated with the estimates derived from DXA with a small Bland-Altman mean percentage differences in values: total body mass (- 250/2000HU: r = 0.985; - 1.10%); total fat mass (- 250/-25HU: r = 0.981; - 1.90%); total lean tissue mass (- 25/150HU: r = 0.972; 3.47%); and total bone mineral content (150/2000HU: r = 0.900; - 0.87%). Although averaged CT values compared well to DXA analysis, there was moderate variation in the individual predicted values. There was near perfect inter- and intra-observer agreement in segmentation volumes for abdominal fat.
CONCLUSIONS
Abdominal volume computed tomography (CT) accurately and reliably estimates total body composition in dogs, but greater variations may be observed in dogs weighing less than 10 kg.
Topics: Abdomen; Absorptiometry, Photon; Adipose Tissue; Animals; Body Composition; Bone Density; Dogs; Female; Male; Tomography, X-Ray Computed
PubMed: 30621710
DOI: 10.1186/s12917-018-1768-6 -
Journal of Anatomy Dec 2021Quantitative functional anatomy of amniote thoracic and abdominal regions is crucial to understanding constraints on and adaptations for facilitating simultaneous...
Quantitative functional anatomy of amniote thoracic and abdominal regions is crucial to understanding constraints on and adaptations for facilitating simultaneous breathing and locomotion. Crocodilians have diverse locomotor modes and variable breathing mechanics facilitated by basal and derived (accessory) muscles. However, the inherent flexibility of these systems is not well studied, and the functional specialisation of the crocodilian trunk is yet to be investigated. Increases in body size and trunk stiffness would be expected to cause a disproportionate increase in muscle force demands and therefore constrain the basal costal aspiration mechanism, necessitating changes in respiratory mechanics. Here, we describe the anatomy of the trunk muscles, their properties that determine muscle performance (mass, length and physiological cross-sectional area [PCSA]) and investigate their scaling in juvenile Alligator mississippiensis spanning an order of magnitude in body mass (359 g-5.5 kg). Comparatively, the expiratory muscles (transversus abdominis, rectus abdominis, iliocostalis), which compress the trunk, have greater relative PCSA being specialised for greater force-generating capacity, while the inspiratory muscles (diaphragmaticus, truncocaudalis ischiotruncus, ischiopubis), which create negative internal pressure, have greater relative fascicle lengths, being adapted for greater working range and contraction velocity. Fascicle lengths of the accessory diaphragmaticus scaled with positive allometry in the alligators examined, enhancing contractile capacity, in line with this muscle's ability to modulate both tidal volume and breathing frequency in response to energetic demand during terrestrial locomotion. The iliocostalis, an accessory expiratory muscle, also demonstrated positive allometry in fascicle lengths and mass. All accessory muscles of the infrapubic abdominal wall demonstrated positive allometry in PCSA, which would enhance their force-generating capacity. Conversely, the basal tetrapod expiratory pump (transversus abdominis) scaled isometrically, which may indicate a decreased reliance on this muscle with ontogeny. Collectively, these findings would support existing anecdotal evidence that crocodilians shift their breathing mechanics as they increase in size. Furthermore, the functional specialisation of the diaphragmaticus and compliance of the body wall in the lumbar region against which it works may contribute to low-cost breathing in crocodilians.
Topics: Abdomen; Alligators and Crocodiles; Animals; Locomotion; Muscle, Skeletal; Respiration
PubMed: 34302302
DOI: 10.1111/joa.13523 -
In Vivo (Athens, Greece) 2022For prediction of many types of clinical outcome, the skeletal muscle mass can be used as an independent biomarker. Manual segmentation of the skeletal muscles is...
BACKGROUND
For prediction of many types of clinical outcome, the skeletal muscle mass can be used as an independent biomarker. Manual segmentation of the skeletal muscles is time-consuming, therefore we present a deeplearning-based approach for the identification of muscle mass at the L3 level in clinical routine computed tomographic (CT) data.
PATIENTS AND METHODS
We conducted a retrospective study of 130 patient datasets. Individual CT slice analysis at the L3 level was fed into a U-Net architecture. As a result, we obtained segmentations of the musculus rectus abdominis, abdominal wall muscles, musculus psoas major, musculus quadratus lumborum and musculus erector spinae in the CT-slice at the L3 level.
RESULTS
The Dice score was 0.95±0.02, 0.86±0.12, 0.93±0.05, 0.92±0.05, 0.86±0.08 for the erector spine, rectus, abdominal wall, psoas and quadratus lumborum muscles, respectively. For the overall skeletal muscle mass, the test data achieved a Dice score of 0.95±0.03.
CONCLUSION
Our network achieved Dice scores larger than 0.86 for each of the five different muscle types and 0.95 for the overall skeletal muscle mass. The subdivision of muscle types can serve as a basis for obtaining future biomarkers. Our network is publicly available so that it might be beneficial for others to improve the clinical workflow within examination of routine CT scans.
Topics: Abdomen; Deep Learning; Humans; Muscle, Skeletal; Psoas Muscles; Retrospective Studies; Tomography, X-Ray Computed
PubMed: 35738592
DOI: 10.21873/invivo.12896 -
Medicine Sep 2022Desmoid-type fibromatosis is a rare benign mesenchymal neoplasm. Only 8% of desmoid-type fibromatosis develops in the abdominal cavity. The mesentery is seldom affected...
RATIONALE
Desmoid-type fibromatosis is a rare benign mesenchymal neoplasm. Only 8% of desmoid-type fibromatosis develops in the abdominal cavity. The mesentery is seldom affected and gastrointestinal stromal tumors need to be considered in the differential diagnosis, particularly when imaging examination shows a tumor containing gases in the abdominal cavity. Only a few cases of gas-containing mesenteric desmoid-type fibromatosis have been reported in the literature.
PATIENT CONCERNS
A 69-year-old male patient presented with hematochezia and intermittent upper abdominal pain.
DIAGNOSIS
Contrast-enhanced computed tomography revealed a 3.9 × 3.6 cm gas-containing mass infiltrating the third portion of the duodenum. The tumor was heterogeneous, with cysts and air bubbles. It showed heterogeneous weak-to-mild enhancement in the solid part. Postoperative pathological examination confirmed a final diagnosis of mesenteric desmoid-type fibromatosis.
INTERVENTIONS
The patient underwent surgical resection of intra-abdominal lesion.
OUTCOMES
No evidence of local recurrence was noted during the 6 months of follow-up.
LESSONS
Accurate preoperative diagnosis is difficult for an intra-abdominal gas-containing mass on computed tomography scan. The appearance of spiculated infiltrative margin suggests the diagnosis of desmoid-type fibromatosis. Further investigation of imaging evidence and treatment methods is necessary.
Topics: Abdominal Pain; Aged; Fibromatosis, Aggressive; Gases; Gastrointestinal Stromal Tumors; Humans; Male; Mesentery; Tomography, X-Ray Computed
PubMed: 36086779
DOI: 10.1097/MD.0000000000030326 -
The Journal of Nutrition, Health & Aging Nov 2009To determine the relationship of abdominal circumference with increased left ventricular mass (LVM) from young adulthood into old age.
PURPOSE
To determine the relationship of abdominal circumference with increased left ventricular mass (LVM) from young adulthood into old age.
METHODS
Cross-sectional echocardiographic images were taken from 182 men and 220 women in the Fels Longitudinal Study 20 to 75 years of age to determine left ventricular mass. Left ventricular mass was divided by stature raised to the power of 2.7 (LVM/ht2.7) in order to minimize the impact of heart size variation from body size without overcompensating for the adverse effect of obesity. Abdominal circumference was measured and BMI calculated from stature and weight and categories of overweight, obesity and abdominal obesity were determined using published cut points. Regression models were used to describe the relationships of age, abdominal circumference, BMI and self-reported physical activity to LVM/ht2.7.
RESULTS
Age, abdominal circumference and BMI were each positively and significantly related to an increased LVM/ht2.7 in men and women (p < 0.05). In the men, multivariate models indicated that abdominal circumference and BMI were both significantly related to an increased LVM/ht2.7, but the inclusion of BMI in these models for the women reduced the association of abdominal circumference and physical activity below significant levels. In the men, there was also a quadratic association of abdominal circumference with LVM/ht2.7 that was significant along with BMI and physical activity. Sex-specific logistic regressions with BMI and abdominal circumference obesity categories did not change or improve the initial findings in men or women.
CONCLUSIONS
In women, increases in abdominal fatness as reflected in abdominal circumference at any age are linearly related to an increase in LVM/ht2.7, but the relationship of overall fatness as reflected in BMI with LVM/ht2.7 is stronger. In men, both abdominal fatness and overall fatness at any age are linearly related to an increase LVM/ht2.7. However, the significant curvilinear association of abdominal circumference and a linear association of BMI and physical activity with LVM/ht2.7 indicate the possible positive covariate relationship of overall muscle mass with LVM/ht2.7. This reflects the physiological changes with age and demonstrate, in part, the complexity of the interpretations of the inter associations of body composition, the cardiovascular system and the aging process, but the impact among the elderly and the known inadequacy of BMI at these ages remains an area for continued clinical study.
Topics: Abdomen; Adipose Tissue; Adult; Aged; Aging; Body Fat Distribution; Body Mass Index; Body Size; Cardiovascular Diseases; Echocardiography; Exercise; Female; Heart Ventricles; Humans; Hypertrophy, Left Ventricular; Logistic Models; Longitudinal Studies; Male; Middle Aged; Obesity; Obesity, Abdominal; Sex Factors; Waist Circumference; Young Adult
PubMed: 19812873
DOI: 10.1007/s12603-009-0219-2 -
Clinical Nutrition (Edinburgh, Scotland) Aug 2021Body composition analysis on CT images is a valuable tool for sarcopenia assessment. We aimed to develop and validate a deep neural network applicable to whole-body CT...
BACKGROUND & AIMS
Body composition analysis on CT images is a valuable tool for sarcopenia assessment. We aimed to develop and validate a deep neural network applicable to whole-body CT images of PET-CT scan for the automatic volumetric segmentation of body composition.
METHODS
For model development, one hundred whole-body or torso F-fluorodeoxyglucose PET-CT scans of 100 patients were retrospectively included. Two radiologists semi-automatically labeled the following seven body components in every CT image slice, providing a total of 46,967 image slices from the 100 scans for training the 3D U-Net (training, 39,268 slices; tuning, 3116 slices; internal validation, 4583 slices): skin, bone, muscle, abdominal visceral fat, subcutaneous fat, internal organs with vessels, and central nervous system. The segmentation accuracy was assessed using reference masks from three external datasets: two Korean centers (4668 and 4796 image slices from 20 CT scans, each) and a French public dataset (3763 image slices from 24 CT scans). The 3D U-Net-driven values were clinically validated using bioelectrical impedance analysis (BIA) and by assessing the model's diagnostic performance for sarcopenia in a community-based elderly cohort (n = 522).
RESULTS
The 3D U-Net achieved accurate body composition segmentation with an average dice similarity coefficient of 96.5%-98.9% for all masks and 92.3%-99.3% for muscle, abdominal visceral fat, and subcutaneous fat in the validation datasets. The 3D U-Net-derived torso volume of skeletal muscle and fat tissue and the average area of those tissues in the waist were correlated with BIA-derived appendicular lean mass (correlation coefficients: 0.71 and 0.72, each) and fat mass (correlation coefficients: 0.95 and 0.93, each). The 3D U-Net-derived average areas of skeletal muscle and fat tissue in the waist were independently associated with sarcopenia (P < .001, each) with adjustment for age and sex, providing an area under the curve of 0.858 (95% CI, 0.815 to 0.901).
CONCLUSIONS
This deep neural network model enabled the automatic volumetric segmentation of body composition on whole-body CT images, potentially expanding adjunctive sarcopenia assessment on PET-CT scan and volumetric assessment of metabolism in whole-body muscle and fat tissues.
Topics: Abdomen; Aged; Body Composition; Female; Fluorodeoxyglucose F18; Humans; Intra-Abdominal Fat; Male; Middle Aged; Muscle, Skeletal; Neural Networks, Computer; Nutrition Assessment; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Republic of Korea; Retrospective Studies; Sarcopenia; Subcutaneous Fat; Whole Body Imaging
PubMed: 34365038
DOI: 10.1016/j.clnu.2021.06.025 -
Journal of Medical Case Reports Apr 2021Clear-cell carcinoma arising from the surgical cesarean section scar is very infrequent. The present study reports two patients with clear-cell carcinoma arising from an...
BACKGROUND
Clear-cell carcinoma arising from the surgical cesarean section scar is very infrequent. The present study reports two patients with clear-cell carcinoma arising from an abdominal wall scar 20 and 23 years after their last cesarean section.
CASE PRESENTATION
Both Iranian patients had prior cesarean sections nearly 20 years earlier. Patients 1 and 2 had transverse and vertical abdominal incisions, respectively. The initial clinical presentation was a huge lower abdominal mass at the site of the previous cesarean section scar. Both patients underwent abdominal wall mass biopsy. The histological analysis revealed the presence of malignancy. Both patients underwent full-thickness resection of the abdominal wall mass. All surgical margins were tumor-free; however, patient 1 had a very narrow tumor-free margin near the pubic symphysis. As the imaging report of patient 2 revealed the presence of a pelvic mass, the exploration of the intraperitoneal space, simple total abdominal hysterectomy (TAH), bilateral salpingo-oophorectomy (BSO), and the excision of enlarged pelvic lymph nodes were performed during the surgery. Six cycles of paclitaxel and carboplatin every 3 weeks as adjuvant chemotherapy was administered for both patients after the surgery. One of the patients had disease recurrence 5 months after the termination of chemotherapy, and the other is still disease-free. These two patients had similar pathology and received a similar initial adjuvant treatment; however, they were different in terms of the direction of tumor spread, tumor distance from the pubic symphysis, status of tumor margins, and surgical procedures.
CONCLUSIONS
We encountered distinct prognoses in the clear-cell carcinoma of cesarean section scars presented herein. The researchers can recommend complete surgical excision of the abdominal wall mass with wide tumor-free margins, exploration of the abdominopelvic space, TAH, and BSO during the first surgery.
Topics: Abdominal Wall; Cesarean Section; Cicatrix; Endometriosis; Female; Humans; Iran; Neoplasm Recurrence, Local; Pregnancy
PubMed: 33810809
DOI: 10.1186/s13256-021-02775-9