scholarly journals Evaluation of Optimized Injection Dose and Acquisition Time Using Body Mass Index for Three-dimensional Whole-body FDG-PET

2004 ◽  
Vol 60 (11) ◽  
pp. 1564-1573 ◽  
Author(s):  
KEIICHI MATSUMOTO ◽  
HAJIME MATSUURA ◽  
EIRI MINOTA ◽  
SETSU SAKAMOTO ◽  
YUJI NAKAMOTO ◽  
...  
PEDIATRICS ◽  
1990 ◽  
Vol 86 (3) ◽  
pp. 440-447 ◽  
Author(s):  
Laura K. Bachrach ◽  
David Guido ◽  
Debra Katzman ◽  
Iris F. Litt ◽  
Robert Marcus

Osteoporosis develops in women with chronic anorexia nervosa. To determine whether bone mass is reduced in younger patients as well, bone density was studied in a group of adolescent patients with anorexia nervosa. With single- and dual-photon absorptiometry, a comparison was made of bone mineral density of midradius, lumbar spine, and whole body in 18 girls (12 to 20 years of age) with anorexia nervosa and 25 healthy control subjects of comparable age. Patients had significantly lower lumbar vertebral bone density than did control subjects (0.830 ± 0.140 vs 1.054 ± 0.139 g/cm2) and significantly lower whole body bone mass (0.700 ± 0.130 vs 0.955 ± 0.130 g/cm2). Midradius bone density was not significantly reduced. Of 18 patients, 12 had bone density greater than 2 standard deviations less than normal values for age. The diagnosis of anorexia nervosa had been made less than 1 year earlier for half of these girls. Body mass index correlated significantly with bone mass in girls who were not anorexic (P < .05, .005, and .0001 for lumbar, radius, and whole body, respectively). Bone mineral correlated significantly with body mass index in patients with anorexia nervosa as well. In addition, age at onset and duration of anorexia nervosa, but not calcium intake, activity level, or duration of amenorrhea correlated significantly with bone mineral density. It was concluded that important deficits of bone mass occur as a frequent and often early complication of anorexia nervosa in adolescence. Whole body is considerably more sensitive than midradius bone density as a measure of cortical bone loss in this illness. Low body mass index is an important predictor of this reduction in bone mass.


Author(s):  
Zachary Merrill ◽  
April Chambers ◽  
Rakié Cham

Body segment parameters (BSPs) such as segment mass and center of mass are used as inputs in ergonomic design and biomechanical models to predict the risk of musculoskeletal injuries. These models have been shown to be sensitive to the BSP values used as inputs, demonstrating the necessity of using accurate and representative parameters. This study aims to provide accurate BSPs by quantifying the impact of age and body mass index on torso and thigh mass and center of mass in working adults using whole body dual energy x-ray absorptiometry (DXA) scan data. The results showed significant effects of gender, age, and body mass index (BMI) on torso and thigh mass and center of mass, as well as significant effects of age and BMI within genders, indicating that age, gender, and BMI need to be taken into account when predicting BSPs in order to calculate representative ergonomic and biomechanical model outputs.


2004 ◽  
Vol 60 (4) ◽  
pp. 491-499 ◽  
Author(s):  
KEIICHI MATSUMOTO ◽  
YASUHIRO WADA ◽  
HAJIME MATSUURA ◽  
TORU FUJITA ◽  
MICHIO SENDA

2019 ◽  
Vol 92 (1103) ◽  
pp. 20190300
Author(s):  
Andrew D. Weedall ◽  
Adrian J. Wilson ◽  
Sarah C. Wayte

Objective: To validate MRI fat measurement protocols using purpose built test objects and by comparison with air-displacement plethysmography (ADP) whole-body fat measurements in non-obese subjects. Methods: Test objects of known fat concentration were used to quantify the accuracy of the MRI measurements. 10 participants with a body mass index in the range 18–30 underwent whole-body MRI using two different Dixon-based sequences (LAVA Flex and IDEAL IQ) to obtain an estimate of their whole-body fat mass. The MRI determined fat mass was compared to the fat mass determined by ADP. Results: MRI test object measurements showed a high correlation to expected fat percentage (r > 0.98). The participant MRI and ADP results were highly correlated (r = 0.99) but on average (mean ± standard deviation) MRI determined a higher fat mass than ADP (3.8 ± 3.1 kg for LAVA Flex and 1.9 ± 3.2 kg for IDEAL IQ). There was no trend in the difference between MRI and ADP with total fat mass. Conclusion: The good agreement between MRI and ADP shows that Dixon-based MRI can be used effectively as a tool in physiological research for non-obese adults. Advances in knowledge: This work found that for ten non-obese subjects body mass index had no effect on the MRI determination of whole-body fat mass.


2004 ◽  
Vol 97 (6) ◽  
pp. 2333-2338 ◽  
Author(s):  
Wei Shen ◽  
Mark Punyanitya ◽  
ZiMian Wang ◽  
Dympna Gallagher ◽  
Marie-Pierre St.-Onge ◽  
...  

A single abdominal cross-sectional computerized axial tomography and magnetic resonance image is often obtained in studies examining adipose tissue (AT) distribution. An abdominal image might also provide additional useful information on total body skeletal muscle (SM) and AT volumes with related physiological insights. We therefore investigated the relationships between abdominal SM and AT areas from single images and total body component volumes in a large and diverse sample of healthy adult subjects. Total body SM and AT volumes were derived by whole body multislice magnetic resonance imaging in 123 men [age (mean ± SD) of 41.6 ± 15.8 yr; body mass index of 25.9 ± 3.4 kg/m2] and 205 women (age of 47.8 ± 18.7 yr; body mass index of 26.7 ± 5.6 kg/m2). Single abdominal SM and AT slice areas were highly correlated with total body SM ( r = 0.71–0.92; r = 0.90 at L4–L5 intervertebral space) and AT ( r = 0.84–0.96; r = 0.94 at L4–L5 intervertebral space) volumes, respectively. R2 increased by only 5.7–6.1% for SM and 2.7–4.4% for AT with the inclusion of subject sex, age, ethnicity, scanning position, body mass index, and waist circumference in the model. The developed SM and AT models were validated in an additional 49 subjects. To achieve equivalent power to a study measuring total body SM or AT volumes, a study using a single abdominal image would require 17–24% more subjects for SM and 6–12% more subjects for AT. Measurement of a single abdominal image can thus provide estimates of total body SM and AT for group studies of healthy adults.


Brachytherapy ◽  
2014 ◽  
Vol 13 (4) ◽  
pp. 332-336 ◽  
Author(s):  
John M. Boyle ◽  
Oana Craciunescu ◽  
Beverley Steffey ◽  
Jing Cai ◽  
Junzo Chino

2014 ◽  
Vol 28 (9) ◽  
pp. 1047-1052 ◽  
Author(s):  
Rafael Oliveira Cavalcante ◽  
Ana Carolina Rabachini Caetano ◽  
Daniela Cristina Nacaratto ◽  
Talita Micheletti Helfer ◽  
Wellington P. Martins ◽  
...  

2020 ◽  
Author(s):  
Roberta Matheoud ◽  
Naema Al-Maymani ◽  
Alessia Oldani ◽  
Gian Mauro Sacchetti ◽  
Marco Brambilla ◽  
...  

Abstract BackgroundTime-of-flight (TOF) PET technology determines a reduction in the noise and improves the reconstructed image quality in low counts acquisitions, such as in overweight patients, allowing a reduction of administered activity and/or imaging time. However, international guidelines and recommendations on 18F-fluoro-2-deoxyglucose (FDG) activity administration scheme are old or only partially account for TOF technology and advanced reconstruction modalities. The aim of this study was to optimize FDG whole-body studies on a TOF PET/CT scanner by using a multivariate approach to quantify how physical figures of merit related to image quality change with acquisition/reconstruction/patient-dependent parameters in a phantom experiment. MethodsThe NEMA-IQ phantom was used to evaluate contrast recovery coefficient (CRC), background variability (BV) and contrast-to-noise ratio (CNR) as a function of changing emission scan duration (ESD), activity concentration (AC), target internal diameter (ID), target-background activity ratio (TBR), and body mass index (BMI). The phantom was filled with an average concentration of 5.3 kBq/mL of FDG solution and the spheres with TBR of 21.2, 8.8, and 5.0 in 3 different sessions. Images were acquired at varying background activity concentration from 5.1 to 1.3 kBq/mL and images were reconstructed for ESD of 30-151 seconds per bed position with and without Point Spread Function (PSF) correction. The parameters were all considered in a single analysis using multiple linear regression methods. ResultsAs expected, CRC depended only on sphere ID and on PSF application, while BV depended on sphere ID, ESD, AC and BMI of the phantom, in order of decreasing relevance. Noteworthy, ESD and AC resulted as the most significant predictors of CNR variability with a similar relevance, followed by the weight of the patient and TBR of the lesion. ConclusionsAC and ESD proved to be effective tools in modulating CNR. ESD could be increased rather than AC to improve image quality in overweight/obese patients to fulfil ALARA principles.


Sign in / Sign up

Export Citation Format

Share Document