Lecture Notes: Radiology and Lung Pathologies

Introduction

• Speaker: N. Cangar
• Guest: Dr. Robert Sue, UCLA Professor of Radiology
• Session type: Interactive with audience response system

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Key Concepts

Pathology-Based vs. Pattern-Based Terms

• Pathology-Based Terms: Related to specific lung diseases and histopathological entities. Examples include:

  • UIP (Usual Interstitial Pneumonia)
  • NSIP (Nonspecific Interstitial Pneumonia)
  • AIP (Acute Interstitial Pneumonia)
  • Organizing Pneumonia
  • Hypersensitivity Pneumonitis
  • Lymphangioleiomyomatosis

• Pattern-Based Terms: Reflect findings on CT scans, can be more vague. Examples include:

  • Reticulations
  • Nodules
  • Cysts
  • Airspace Disease

Patterns of Lung Pathology

1. Reticulations: Seen in lung diseases like UIP, NSIP, chronic HP.
2. Nodules: Commonly associated with sarcoidosis, metastases, and subacute HP.
3. Cysts: Associated with conditions such as lymphangioleiomyomatosis (LAM) and LCH (Langerhans Cell Histiocytosis).
4. Airspace Disease: Includes conditions like organizing pneumonia and acute interstitial pneumonia.

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Clinical Cases Overview

Case Discussion

• A 77-year-old man presented with progressive dyspnea.
  • Most Likely Diagnosis: NNIP or asbestosis based on reticular pattern and lower lung field predominance.

Reticulations

• Distribution is crucial:
  • Patterns to identify: Upper vs. lower, central vs. peripheral, segmental vs. diffuse.
• Important characteristics in UIP: Peripheral reticulation, basal predominance, honeycombing.

Honeycombing

• Defined as thick-walled polygonal structures with air density at the center.
• Affects prognosis and recognition of interstitial lung disease.

NSIP vs UIP

• NSIP: More homogeneous; can have significant ground glass attenuation; sparing of subpleural regions.
• UIP: More fibrotic changes, significant honeycombing, and nearly no subpleural sparing.

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Specific Conditions and Radiographic Patterns

Chronic Hypersensitivity Pneumonitis (HP)

• Characterized by: Ground glass opacities, reticulations, and potential air trapping.
• Important to distinguish from NSIP and UIP based on patterns and distribution.

Sarcoidosis

• Stage 2: Micronodular patterns, often with mediastinal adenopathy.

Random Nodular Patterns

• Commonly associated with hematogenous spread of infection (e.g., TB) and malignancy.

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Cystic Lung Diseases

• Important entities include:
  • LAM
  • LCH
• Cysts in lung diseases can present as rounded, air-filled spaces with or without walls.

Small Airways Disease

• Observed through patterns like tree-in-bud or bronchiolectasis.
• Consider involvement of small airways in assessing presentations.

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Airspace Diseases Overview

• Organizing Pneumonia: Characterized by patchy airspace opacities; may present with reverse halo sign.

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Summary

• Review of the different categories: Reticular patterns, nodular diseases, cystic patterns, and airspace diseases.
• Clinical History: Always crucial to narrow down the differential diagnoses.

Audience Interaction

• Engaging with society around case-based questions throughout the session.

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Final Remarks

• Participants were praised for high accuracy in diagnosing.
• Closing remarks by Dr. Sue and N. Cangar with gratitude to attendees.