Body Composition Analysis & DXA Clinical Applications Flashcards
7 cards from real DEXA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Body Composition Analysis & DXA Clinical Applications flashcards as text
Which three compartments does a standard DXA body composition scan quantify?
Answer: Lean mass, fat mass, and bone mineral content
DXA partitions the body into lean soft tissue mass, fat mass, and bone mineral content (BMC), making it a three-compartment model.
In DXA body composition analysis, the term 'android fat distribution' refers to excess fat primarily located in the:
Answer: Abdominal and trunk region
Android (apple-shaped) fat distribution is characterized by excess adipose tissue in the abdominal and trunk region, which is associated with higher cardiometabolic risk.
What is the Visceral Adipose Tissue (VAT) region automatically estimated by advanced DXA software typically approximated from?
Answer: The android region scan data combined with validated algorithms
Modern DXA systems estimate VAT using the fat distribution within the android region combined with proprietary validated algorithms, without requiring MRI or CT.
Which metric best describes the ratio of appendicular lean mass to body weight squared, commonly used to screen for sarcopenia?
Answer: Relative skeletal muscle index (RSMI)
The Relative Skeletal Muscle Index (RSMI) is calculated as appendicular lean mass (kg) divided by height squared (m²) and is a primary DXA-based criterion for diagnosing sarcopenia.
When performing a whole-body DXA scan for body composition, the patient's arms must be:
Answer: Positioned palms down, slightly separated from the body sides
Arms are placed palms down with a slight gap from the torso so that the software can correctly separate arm from trunk regions during segmentation.
A 'total body less head' (TBLH) measurement is frequently reported in pediatric DXA because:
Answer: The head contains a disproportionately large amount of bone mass in children, skewing whole-body BMD
In children, the skull contributes disproportionately to total BMD; excluding the head reduces variability and improves the sensitivity of the measurement for assessing skeletal growth and disease.
Which of the following clinical conditions is a primary indication for using DXA body composition analysis rather than a standard bone density scan?
Answer: Monitoring lean mass changes in a patient undergoing cancer cachexia treatment
Monitoring lean (muscle) mass changes during cancer cachexia treatment is a body composition application of DXA that goes beyond bone density assessment.
How this page was made: written with AI tools and published by Nathan Beja, founder of Practice Test Geeks, who is responsible for its content. Exam facts are checked against the official sources listed below. Not reviewed by a subject-matter expert. Editorial policy
Sources & references
Exam facts on this page (fees, format, dates, passing scores) are checked against these official sources; the date is our last check. Editorial policy