Warning: session_start(): open(/var/lib/php/session/sess_q1irdh85hsp0ajcrc5dd7hm2a3, O_RDWR) failed: Permission denied (13) in /home/radiologykey.com/public_html/wp-content/plugins/paid-memberships-pro/paid-memberships-pro.php on line 28
Nonspecific Interstitial Pneumonia | Radiology Key

Nonspecific Interstitial Pneumonia



Nonspecific Interstitial Pneumonia


Jud W. Gurney, MD, FACR

Tan-Lucien H. Mohammed, MD, FCCP










Axial NECT shows peribronchial peripheral ground-glass opacities image, which exceed reticular opacities. Note the subpleural sparing image.






Coronal NECT shows basilar fan-shaped image ground-glass and reticular opacities extending along the bronchovascular pathways. Subpleural sparing image is noted in this patient with NSIP.


TERMINOLOGY


Abbreviations and Synonyms



  • Nonspecific interstitial pneumonia (NSIP)


Definitions



  • 1 of the idiopathic interstitial pneumonias, less common than idiopathic pulmonary fibrosis (IPF), but with better prognosis than IPF



    • Distinguished by temporal and spatial uniformity of histologic findings


IMAGING FINDINGS


General Features



  • Best diagnostic clue: Traction bronchiectasis out of proportion to reticular opacities


  • Patient position/location: Peribronchovascular basilar distribution


  • Size: Generally involves 25-35% of lung volume


  • Morphology: Ground-glass opacities > reticular opacities


CT Findings



  • Morphology



    • Reticular opacities (85%)



      • Often admixed with ground-glass opacities


      • Ground-glass opacities, when present, usually exceed reticular opacities


      • Combined ground-glass opacities and reticular opacities may result in crazy-paving pattern


    • Traction bronchiectasis (80%)



      • Often out of proportion to degree of reticular opacities


      • Usually associated with considerable lobar volume loss


      • Mean 20% of total lung volume


    • Ground-glass opacities (75%)



      • Ground-glass opacities often exceed reticular opacities, especially early


      • Mean 25-35% of lung volume with ground-glass opacities


      • May have mosaic perfusion pattern (5%)


    • Peribronchial thickening (5%)


    • Honeycombing rare (5%) (so uncommon, should suggest usual interstitial pneumonitis [UIP])




      • May have fine honeycombing: Microcystic honeycombing


      • Isolated enlarged airspaces may be present (not clustered together like honeycombing)


    • Consolidation less common, mean 10% of lung volume


  • Distribution



    • Symmetry common


    • Craniocaudad



      • Lower (92%)


      • Diffuse (8%)


    • Axial



      • Diffuse (60%)


      • Peripheral (35%)


    • Subpleural sparing (20%)



      • Very thin rim


    • Bronchovascular distribution, often fan-shaped from hilum to lung periphery


  • Evolution



    • Up to 30% over 3-year period evolve to more UIP pattern


    • Reversible findings: Ground-glass opacities, reticular opacities, traction bronchiectasis


  • Adenopathy (80%)



    • Mediastinal lymph node enlargement < 2 cm short axis diameter


    • Most common location right paratracheal nodal station (American Thoracic Society [ATS] region 4) or subcarinal (ATS region 7)


    • Direct positive correlation between extent of parenchymal involvement and presence of lymphadenopathy


  • Accuracy



    • Should make confident diagnosis in 80% of cases


    • Positive predictive value of confident diagnosis = 70-80%


Radiographic Findings



  • Radiography



    • Radiography: Nonspecific, abnormal (90%)


    • Bibasilar interstitial thickening (“lace-like” honeycombing)


Imaging Recommendations



  • Best imaging tool: HRCT to detect and characterize interstitial lung disease


DIFFERENTIAL DIAGNOSIS


Idiopathic Pulmonary Fibrosis (IPF)



  • Honeycombing more common


  • Subpleural peripheral location, more common



    • No subpleural sparing


  • Ground-glass extent less common


  • Histopathology: Temporal inhomogeneity of lung injury


  • Poorer prognosis than NSIP


Hypersensitivity Pneumonitis



  • May have NSIP pattern


  • Occupational and home environmental history extremely important to discover known antigens


  • Mosaic perfusion pattern more common


  • Chronic disease usually more severe in mid and upper lung zones, honeycombing more common


Cryptogenic Organizing Pneumonia (COP)



  • Consolidation usually more prominent than in NSIP


  • May have multiple pulmonary nodules or single mass, uncommon with NSIP


  • Reverse halo sign not seen with NSIP


  • Reticular opacities uncommon but similar to NSIP


Desquamative Interstitial Pneumonia (DIP)



  • Smokers; smoking less common in NSIP


  • Diffuse ground-glass opacities with scattered cysts


  • Traction bronchiectasis uncommon


Pulmonary Alveolar Proteinosis (PAP)



  • “Crazy-paving” appearance, less common with NSIP


  • Central and geographic distribution, not bronchovascular or peripheral


  • No traction bronchiectasis



Sarcoidosis



  • Nodules: Most common pattern follows lymphatic pathways



    • Centrilobular, bronchovascular, and subpleural


  • Occasionally have predominant ground-glass opacities



    • Would not be associated with traction bronchiectasis if ground-glass opacities were predominant pattern


  • Adenopathy more common and nodes larger, especially in early disease


PATHOLOGY


General Features

Sep 20, 2016 | Posted by in RESPIRATORY IMAGING | Comments Off on Nonspecific Interstitial Pneumonia
Premium Wordpress Themes by UFO Themes

Warning: Unknown: open(/var/lib/php/session/sess_q1irdh85hsp0ajcrc5dd7hm2a3, O_RDWR) failed: Permission denied (13) in Unknown on line 0

Warning: Unknown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct (/var/lib/php/session) in Unknown on line 0