Pulmonary nodule

At the time the article was created Jeremy Jones had no recorded disclosures.

At the time the article was last revised Liz Silverstone had no financial relationships to ineligible companies to disclose.

• Pulmonary nodule
• Lung nodules
• Intrapulmonary nodules
• Lung nodule
• Intrapulmonary nodule
• Pulmonary nodules

Pulmonary nodules are small, rounded opacities within the pulmonary interstitium. Pulmonary nodules are common and, as the spatial resolution of CT scanners has increased, detection of smaller and smaller nodules has occurred, which are more often an incidental finding.

On this page:

• Classification
• Radiographic features
• Differential diagnosis
• Practical points
• See also
• References

• Cases and figures
• Imaging differential diagnosis

Classification

Pulmonary nodules can be classified according to size, morphology and/or distribution.

Size

• miliary nodules:
• pulmonary micronodule:
• pulmonary nodule: 4-30 mm
• pulmonary mass: >30 mm

Morphology

• solid pulmonary nodules
  • calcified pulmonary nodules

  Distribution

  • perilymphatic pulmonary nodules
    • perifissural pulmonary nodules
    • subpleural pulmonary nodules

    Radiographic features

    They are generally homogeneous (without air bronchograms or alveolograms) and are well-defined since their margins are sharp and they are surrounded by normally aerated lung parenchyma. They are quite separate from airspace nodules that often have an irregular margin and are usually ~8 mm in diameter. (For further discussion, see the article on nodular opacification.)

    Differential diagnosis

    The differential diagnosis for a nodule can be refined by its size, location, and density. Solitary pulmonary nodules and hyperdense pulmonary nodules are discussed further elsewhere.

    A micronodular or miliary pattern is predominately seen in granulomatous processes, hematogenous pulmonary metastases, and pneumoconioses. Nodules and masses are most often seen in metastatic disease to the lung.

    Always be aware of artifacts, especially on radiographs, where buttons or nipple shadows can often be mistaken for a true pulmonary nodule 7 .

    Practical points

    See also

    • pulmonary mass
    • incidental lung nodules
      • British Thoracic Society guidelines for pulmonary nodules
      • Fleischner Society pulmonary nodule recommendations
      • Brock model

      Quiz questions

      References

      • 1. Boitsios G, Bankier A, Eisenberg R. Diffuse Pulmonary Nodules. AJR Am J Roentgenol. 2010;194(5):W354-66. doi:10.2214/AJR.10.4345 - Pubmed
      • 2. MacMahon H, Austin J, Gamsu G et al. Guidelines for Management of Small Pulmonary Nodules Detected on CT Scans: A Statement from the Fleischner Society. Radiology. 2005;237(2):395-400. doi:10.1148/radiol.2372041887 - Pubmed
      • 3. Prosch H, Strasser G, Oschatz E, Schober E, Schneider B, Mostbeck G. Management of Patients with Small Pulmonary Nodules: A Survey of Radiologists, Pulmonologists, and Thoracic Surgeons. AJR Am J Roentgenol. 2006;187(1):143-8. doi:10.2214/AJR.05.1229 - Pubmed
      • 4. Gould M, Donington J, Lynch W et al. Evaluation of Individuals with Pulmonary Nodules: When is It Lung Cancer? Diagnosis and Management of Lung Cancer, 3rd Ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 2013;143(5 Suppl):e93S-e120S. doi:10.1378/chest.12-2351 - Pubmed
      • 5. Snoeckx A, Reyntiens P, Desbuquoit D et al. Evaluation of the Solitary Pulmonary Nodule: Size Matters, but Do Not Ignore the Power of Morphology. Insights Imaging. 2018;9(1):73-86. doi:10.1007/s13244-017-0581-2 - Pubmed
      • 6. Raad R, Suh J, Harari S, Naidich D, Shiau M, Ko J. Nodule Characterization: Subsolid Nodules. Radiol Clin North Am. 2014;52(1):47-67. doi:10.1016/j.rcl.2013.08.011 - Pubmed
      • 7. Dr Stephen Ellis. Interpreting Chest X Rays. (2010) ISBN: 9781904842774 - Google Books
      • 8. Munden R, Chiles C, Boiselle P, Sicks J, Aberle D, Gatsonis C. Micronodules Detected on Computed Tomography During the National Lung Screening Trial: Prevalence and Relation to Positive Studies and Lung Cancer. J Thorac Oncol. 2019;14(9):1538-46. doi:10.1016/j.jtho.2019.05.045 - Pubmed
      • 9. Sánchez M, Benegas M, Vollmer I. Management of Incidental Lung Nodules
      • 10. Bankier A, MacMahon H, Goo J, Rubin G, Schaefer-Prokop C, Naidich D. Recommendations for Measuring Pulmonary Nodules at CT: A Statement from the Fleischner Society. Radiology. 2017;285(2):584-600. doi:10.1148/radiol.2017162894 - Pubmed
      • 11. Bankier A, MacMahon H, Colby T et al. Fleischner Society: Glossary of Terms for Thoracic Imaging. Radiology. 2024;310(2):e232558. doi:10.1148/radiol.232558 - Pubmed

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