Imaging & Screening
Non-invasive tests that give you a structural and functional picture of cardiovascular risk, body composition, liver health, and metabolic function — beyond what blood tests alone can show.
Coronary Artery Calcium Scan
CAC ScanDirectly measure calcified plaque in the coronary arteries to assess structural cardiovascular risk.
What It Measures
The amount of calcified atherosclerotic plaque in the coronary arteries, expressed as a CAC score (Agatston units). A score of zero indicates no detectable calcified plaque. Higher scores indicate greater plaque burden and cardiovascular risk.
Typical Use Cases
- Assessing cardiovascular risk in asymptomatic adults aged 40–75
- Guiding statin therapy decisions in intermediate-risk individuals
- Establishing a baseline for cardiovascular risk tracking
- Identifying high-risk individuals who appear low-risk on standard panels
Benefits
- Provides direct structural evidence of atherosclerosis — not a proxy
- A score of zero confers very low 10-year cardiovascular risk
- Low radiation dose (~1 mSv, equivalent to a few months of background radiation)
- Widely available and typically costs $75–$150 out of pocket
- Results are highly reproducible and well-validated
Limitations
- Measures only calcified plaque — does not detect soft (non-calcified) plaque
- Not appropriate for people with known coronary artery disease
- Involves ionizing radiation (though low dose)
- Does not provide information about stenosis or flow limitation
Related Topics
Coronary CT Angiography
CCTAVisualize the coronary arteries in detail to assess both calcified and non-calcified plaque, and evaluate stenosis.
What It Measures
The anatomy of the coronary arteries including the presence, location, and composition of plaque (calcified and non-calcified), and the degree of luminal narrowing (stenosis). Provides a more complete picture of coronary artery disease than the CAC scan alone.
Typical Use Cases
- Evaluating chest pain or symptoms suggestive of coronary artery disease
- Assessing plaque burden beyond what the CAC scan captures
- Evaluating coronary anatomy before cardiac procedures
- Identifying high-risk plaque features (low-attenuation, positive remodeling)
Benefits
- Detects both calcified and non-calcified (soft) plaque
- Provides information about stenosis severity
- Non-invasive alternative to catheter-based angiography for many indications
- High negative predictive value — a normal CCTA effectively rules out significant CAD
Limitations
- Higher radiation dose than CAC scan (~3–5 mSv)
- Requires contrast dye injection (iodinated contrast)
- More expensive than CAC scan — often $500–$1,500+
- Image quality affected by heart rate and calcification
- Typically requires a physician referral
Related Topics
Carotid Intima-Media Thickness
CIMTMeasure the thickness of the carotid artery wall as a surrogate marker of systemic atherosclerosis.
What It Measures
The combined thickness of the intima and media layers of the carotid artery wall, measured via ultrasound. Increased CIMT reflects arterial wall thickening and early atherosclerosis. It is used as a surrogate marker for cardiovascular risk and to track the progression or regression of atherosclerosis over time.
Typical Use Cases
- Assessing subclinical atherosclerosis in intermediate-risk individuals
- Tracking arterial health changes over time with lifestyle or therapeutic interventions
- Complementing CAC scan data — CIMT detects non-calcified changes
- Evaluating cardiovascular risk in younger adults where CAC may be zero
Benefits
- No radiation — uses ultrasound
- Can detect early arterial changes before calcification occurs
- Useful for tracking treatment response over time
- Provides information about both carotid and systemic arterial health
Limitations
- Results are operator-dependent — quality varies by technician and equipment
- Less standardized than CAC scoring
- Not as widely available as CAC scanning
- Predictive value is debated compared to CAC
Related Topics
DEXA Scan
DEXAMeasure body composition — bone mineral density, lean mass, and fat mass — with high precision.
What It Measures
Bone mineral density (BMD) at the spine and hip, total body fat percentage, lean muscle mass, visceral adipose tissue (VAT) area, and regional body composition. DEXA is the gold standard for body composition assessment and bone density measurement.
Typical Use Cases
- Assessing bone mineral density for osteoporosis screening
- Measuring visceral adipose tissue (a key metabolic risk marker)
- Tracking muscle mass changes with resistance training or aging
- Establishing a body composition baseline for health optimization
- Monitoring response to dietary and exercise interventions
Benefits
- Gold standard for body composition and bone density measurement
- Measures visceral fat directly — a key metabolic health marker
- Very low radiation dose (~0.001 mSv)
- Highly reproducible — excellent for tracking changes over time
- Widely available at hospitals, imaging centers, and some gyms
Limitations
- Does not assess cardiovascular risk directly
- Results can vary between different DEXA machines and software versions
- Hydration status can affect results
- Typically costs $50–$150 out of pocket
Related Topics
FibroScan
Non-invasively assess liver stiffness (fibrosis) and fat content (steatosis) without a liver biopsy.
What It Measures
Liver stiffness (measured in kilopascals, kPa) as a proxy for fibrosis, and the controlled attenuation parameter (CAP) as a measure of hepatic steatosis (fat content). FibroScan uses transient elastography — a specialized ultrasound technique — to assess liver health.
Typical Use Cases
- Screening for non-alcoholic fatty liver disease (NAFLD) in metabolically at-risk individuals
- Monitoring liver health in people with elevated liver enzymes (ALT, GGT)
- Assessing liver fibrosis in people with chronic liver conditions
- Tracking liver health changes with dietary and lifestyle interventions
Benefits
- Non-invasive — no needles, no radiation
- Provides both fibrosis and steatosis data in a single test
- Results available immediately
- Well-validated against liver biopsy for fibrosis staging
Limitations
- Less accurate in people with high BMI or ascites
- Not widely available outside hepatology clinics and some imaging centers
- Requires a physician referral in most settings
- Does not replace biopsy for definitive fibrosis staging in all cases
Related Topics
Continuous Glucose Monitor
CGMTrack real-time glucose levels continuously to understand how food, exercise, sleep, and stress affect blood sugar.
What It Measures
Interstitial glucose concentration every 1–5 minutes, providing a continuous glucose curve rather than a single snapshot. Key metrics include time in range (TIR), glucose variability, post-meal glucose spikes, fasting glucose trends, and nocturnal glucose patterns.
Typical Use Cases
- Understanding personal glucose responses to specific foods
- Identifying foods that cause disproportionate glucose spikes
- Assessing the impact of exercise, sleep, and stress on glucose
- Establishing a metabolic health baseline
- Monitoring glucose management in people with diabetes or prediabetes
Benefits
- Provides continuous data — not a single snapshot
- Reveals glucose variability and post-meal patterns that fasting glucose misses
- Immediate feedback on lifestyle interventions
- Consumer-accessible devices available without a prescription in many countries
- Powerful educational tool for understanding personal metabolic responses
Limitations
- Measures interstitial glucose — lags behind blood glucose by ~10–15 minutes
- Accuracy varies by device and calibration
- Requires sensor replacement every 10–14 days
- Cost can be significant without insurance coverage ($100–$200/month)
- Not a diagnostic tool for diabetes — requires confirmatory blood testing
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Disclaimer: All content is for educational purposes only. Imaging and screening decisions should be made in consultation with a qualified healthcare professional based on your individual clinical context, risk factors, and medical history.