🫁

Understanding Pulmonary Nodules in Radiology

May 6, 2025

Lecture on Pulmonary Nodules in Chest Radiology

Introduction

  • Speaker: Dave Nagger, Chest Radiologist at UCSF
  • Focus: Pulmonary nodules in chest radiology
  • Objective: Enhance specificity in assessing pulmonary nodules

Approach to Pulmonary Nodules

  1. Identify definitely benign features
  2. Provide follow-up recommendations for small nodules
  3. Assess risk for larger nodules, including PET scan evaluations

Definitely Benign Features

  1. Benign Calcifications
    • Types: Totally calcified granuloma, concentric, popcorn of a hamartoma
    • Tip: Thin slices can help identify calcifications
  2. Fat in Nodules
    • Measurable in soft tissue windows
  3. Long-term Stability
    • Solid nodules: 2 years follow-up needed
    • Ground glass nodules: At least 3 years follow-up, as they can become invasive
  4. Small Nodules in Young Individuals
    • Criteria: 8 mm or smaller, Age 35 or younger

Follow-up Recommendations for Small Nodules

  • Utilize Follow-up Recommendation Table (10 years old)
  • Simplified memory strategy:
    • Low Risk:
      • <4 mm: No follow-up
      • Medium-sized: 1 follow-up at 1 year
      • Large: 2 follow-ups in 2 years
    • High Risk:
      • Same as above but more frequent follow-ups

Assessing Risk of Larger Nodules

  1. Size & Growth
    • Larger nodules (>8 mm) have increased risk
    • Continuous growth is concerning
    • Slow/moderate growth indicates risk
  2. Characteristics
    • Borders: Speculation suggests cancer
    • Cavitation: Thick walls suggest malignancy
    • Density: Ground glass nodules have higher risk of neoplasia

PET Scan in Nodules

  • Assess risk through PET
  • Artifacts affecting PET readings:
    1. Misregistration
    2. Attenuation correction errors
    3. Motion
    4. Size impact on readings
  • Accurate low activity indicates low risk

Conclusion

  • Key assessments: Benign features, follow-up strategies, risk evaluation using CT and PET
  • PET mostly used in complex cases or when surgical risk is high
  • Importance of accurate PET use to lower unnecessary biopsies

Study Questions

  • SAM questions available in booklet for further assessment

Full transcript