← All decks
Radiology
Pulmonary Scintigraphy
Built from Fundamentals of Diagnostic Radiology
What’s inside
8 sections · 98 slides
Overview
- What a lung scan does
- Pulmonary scintigraphy roadmap
Anatomy and Physiology
Segmental anatomy, collateral ventilation, and gravity gradients
- Segmental anatomy of the lungs
- Pulmonary segment anatomy
- Collateral ventilation pathways
- Gravity and ventilation
- Position and perfusion
- Ventilation–perfusion matching
- V/Q mismatch — hallmark of PE
Ventilation Lung Scan
Radioactive gases and aerosols map regional airflow
- Ventilation agents at a glance
- Xenon-133
- Xenon-127
- Krypton-81m
- Tc-99m aerosols
- Aerosol particle deposition
- Aerosol clearance and dosimetry
- Gas delivery and safety
- Xenon-133 ventilation technique
- Three phases of xenon ventilation
- Washout and positioning
- Kr-81m and aerosol technique
- Aerosol dosing order
Perfusion Lung Scan
Capillary blockade maps regional blood flow
- Capillary blockade principle
- How perfusion scanning works
- Tc-99m MAA
- MAA clearance and dose
- Reduced-particle patients
- Perfusion dosimetry
- Injection technique
- Imaging positions
V/Q Scans
Indications, normal patterns, and abnormal findings
- Indications
- CTA versus V/Q scan
- CT pulmonary angiogram with MDCT
- Pregnancy imaging choice
- Breast radiation dose
- Normal ventilation scan
- Normal perfusion scan
- Normal V/Q scan
- Mediastinal effects on perfusion
- Abnormal scans
- Abnormal ventilation
Pulmonary Embolism
Clinical features, risk factors, and imaging findings
- PE epidemiology and risk
- Where emboli come from
- Clinical presentation
- CXR findings of PE
- CT and MRI for PE
- Acute PE on CTA
- CT venography for DVT
V/Q Scan Interpretation
Defects, diagnostic criteria, and probability
- Classic PE pattern
- High-probability V/Q scan
- Analyzing defects
- Sizing segmental defects
- Matched versus mismatched defects
- Two perfusion defect patterns
- Nonsegmental defects
- Low-probability perfusion with pleural effusions
- Diagnostic criteria
- Amended PIOPED criteria
- Intermediate-probability V/Q scan
- Stripe sign
- Fissure sign
- PIOPED study results
- High-probability predictive value
- Negative predictive value
- Clinical assessment matters
- Wells criteria for PE
- Combining scan and clinical suspicion
- Intermediate-probability next steps
- Intermediate-probability mismatched defects
- Confirming with angiography
- V/Q SPECT and low-dose CT
- Low-dose CT benefits
- High-probability V/Q with SPECT
- Follow-up after anticoagulation
- Early follow-up scans
- Recurrent pulmonary emboli on serial V/Q
- Recurrent pulmonary emboli — follow-up perfusion
- False-positive V/Q scans
- False-negative V/Q scans
Nonthromboembolic Pulmonary Disease
Asthma, COPD, tumors, inflammation, and inhalation injury
- Asthma
- Lung neoplasms
- Quantitative perfusion lung scan
- Quantitative perfusion lung scan
- Quantitative ventilation and perfusion
- COPD ventilation
- COPD perfusion
- COPD with matched V/Q defects
- COPD ventilation and perfusion
- Inflammatory and infectious disease
- Aerosol clearance in inflammation
- Smoke inhalation
- Key takeaways
- Suggested Readings
- Suggested Readings (continued)
- Suggested Readings (continued)
- Suggested Readings (continued)
- Suggested Readings (continued)
- Brant and Helms' Fundamentals of Diagnostic Radiology