Radiology2- Lung Diseases

  1. What are causes of artifactual unstructured interstitial pattern, and how can you eliminate them when trying to rule in disease?
    • underexposure: if you can visualize the thoracic vertebrae well, it is appropriately exposed
    • expiration rads: cranially displaced diaphragm and increased contact between cardiac silhouette and diaphragm means it was probably taken during exhalation
  2. What are the most common causes of non-cavitary structural interstitial patterns? (4) What are some less common causes? (6)
    • Primary lung tumor
    • Pulmonary metastases
    • Granulomas (mycotic pneumonia)
    • Thoracic wall lesion- not within lungs, take multiple views to eliminate this possibility
    • Less common: traumatic bulla, hematoma, abscess, cyst, mucus in bronchus, lymphosarcoma (uncommon)
  3. Describe the radiographic appearance of pulmonary metastases. (3)
    • non-cavitary (usually) unstructured interstitial pattern
    • multiple, round nodules of various sizes
    • usually in middle to peripheral aspects of lungs
    • [more common than primary lung tumors]
  4. Describe the radiographic appearance of mycotic pneumonia. (3)
    • Disseminated structural interstitial pattern (milliary if nodules are very small)
    • nodules are usually the same size
    • frequently accompanied by tracheobronchial lymphadenopathy
    • [Blasto, Histo, Coccidomycosis]
  5. Describe the typical radiographic appearance of a primary lung tumor. (4)
    • structured interstitial pattern
    • usually solitary mess lesion
    • usually arise in the periphery
    • may be cavitated if communicating with a bronchus
    • [bronchogenic carcinomas most common]
  6. What are 4 other radiographic DDx for a primary lung tumor?
    • metastatic tumor
    • pulmonary granuloma
    • pulmonary abscess (esp if cavitated)
    • traumatic cyst (area of lung full of blood- should have Hx of trauma)
  7. What are the most common differentials for a cavitary structural interstitial pattern? (3) What are some less common causes? (5)
    • Paragonimiasis
    • Abscess
    • Bulla
    • Less common: primary lung tumor, pulmonary mets, mycotic granuloma, cyst, bronchiectasis
  8. Describe the typical radiographic appearance of a pulmonary abscess. (3)
    • structured interstitial pattern, often cavitated
    • focal, walled-off
    • chronic- discrete mass, acute- irregularly margined
  9. Describe the typical radiographic appearance of a pulmonary bulla. (3)
    • cavitated structured interstitial pattern
    • spherical, radiolucent area(s)
    • smooth, thin-walled
    • [congenital, traumatic, rarely infectious]
  10. What artifact mimics an unstructured interstitial pattern?
  11. How do you differentiate between an unstructured interstitial and an alveolar pattern?
    • if you can see the blood vessels around each bronchus- UNSTRUCTURED INTERSTITIAL
    • if you cannot see the blood vessels- ALVEOLAR
  12. What are the differentials for unstructured interstitial and alveolar patterns? (5)
    • blood (contusions, hemorrhage)
    • pus (aspiration, bronchopneumonia, septic)
    • water (cardiogenic or non-cardiogenic edema)
    • absence of air (atelectesis- expiration or pleural dz)
    • less commonly cells
  13. Describe "disease in transition".
    as bacterial infection worsens, starts with unstructured interstitial pattern that progresses to alveolar pattern; as the lung lobe then recovers, it transitions from alveolar pattern to an unstructured interstitial pattern then back to normal
  14. What is "geriatric thorax"?
    • old-age change
    • mild fibrosis, severity depending on amount of pollutants inhaled throughout life, scarring from old lesions
  15. Describe the radiographic appearance of cariogenic pulmonary edema in dogs. (3)
    • unstructured interstitial early, alveolar late/ severe
    • secondary to left heart failure- signs of HF (enlarged left heart, rounded cardiac silhouette, enlarged pulmonary veins)
    • hilar and perihilar location
  16. Describe cardiogenic pulmonary edema in cats. (3)
    • can look like anything, does not follow typical peri-hilar distribution
    • very irregular distribution pattern
    • mainly look for cardiac changes
  17. What are causes of non-cardiogenic pulmonary edema? (7)
    • neurologic (head trauma, seizure, electric shock)
    • severe allergic reaction
    • advanced uremia
    • pancreatitis
    • irritating inhalants
    • drowning
    • radiation damage
    • [overall, very uncommon]
  18. Describe the radiographic appearance of non-cardiogenic pulmonary edema.
    • distribution is generalized (compared to cardiogenic edema), commonly more peripheral
    • heart and pulmonary vein size is normal
  19. What are potential causes of localized interstitial patterns on thoracic radiographs? (6)
    • Partial lobe collapse
    • Contusions
    • Hemorrhage
    • Pulmonary embolism (can also have completely normal looking rads- CT is better)
    • Bronchial FB
    • Disease in transition
  20. What are potential causes of localized alveolar patterns on thoracic radiographs? (7)
    • Bronchopneumonia
    • Edema
    • Hemorrhage
    • Collapsed lobe (airway obstruction or pleural effusion)
    • Primary lung tumor
    • Pulmonary metastasis
    • Pulmonary infarct
    • [remember: exhalation is a type of atelectasis...this is why we take rads on full inspiration]
  21. Describe the different potential appearances of atelectasis on radiographs.
    • Unstructured interstitial pattern most common (esp if only a little of the gas is removed from the lobe)
    • Alveolar pattern also possible (esp if all or most of the air is removed)
  22. What are potential causes of atelectasis? (3 general, 6 specific)
    • Incomplete aeration: film made during expiration, prolonged recumbency
    • Airway obstruction: internal blockage (FB), external compression (tumor)
    • Increased intrapleural pressure: pneumothorax, pleural effusion
  23. How might pulmonary hemorrhage appear radiographically?
    • interstitial or alveolar
    • look for other signs of trauma (as trauma is the most common cause....coagulopathy also possible)- rib fractures, pleural effusion, neumothorax, diaphragmatic hernia
  24. What are some causes of generalized alveolar pattern on thoracic radiographs? (5)
    • severe bronchopneumonia
    • severe edema
    • severe pulmonary contusions
    • near-drowning
    • smoke inhalation (as in house fire, not cigarette smoke)
  25. What are the possible radiographic appearances of bacterial pneumonia? (3)
    • early- unstructured interstitial pattern, later- alveolar pattern [once you start treatment and it starts resolving, goes back to interstitial]
    • bronchial pattern- if spread via airways, lobar sign
    • hematogenous spread- patchy, multifocal distribution around vessels
  26. What are the most common locations for bronchopneumonia and aspiration pneumonia? (3)
    • [cranioventral lung lobes]
    • right cranial lung lobe
    • right middle lung lobe (ESP WITH MEGAESOPHAGUS- most common location for aspiration pneumonia with megaesophagus)
    • left cranial lung lobes
  27. How does aspiration pneumonia appear radiographically?
    • unstructured interstitial pattern or alveolar pattern
    • depends on the amount of fluid aspirated and the nature of the aspirated material
  28. The distribution of aspiration pneumonia depends on...
    • patient position at time of aspiration
    • passive aspiration--> right cranial and right middle lobes most common
    • forceful aspiration--> right caudal most common
  29. What are the causes of a bronchial pattern on thoracic radiographs? (4)
    • bronchial mineralization
    • allergic bronchitis
    • chronic bronchitis
    • peribronchial cuffing (esp with bronchopneumonia)
  30. Describe allergic bronchitis in cats? (4)
    • feline asthma
    • peribronchial infiltrate of eosinophils and mononuclear cells
    • if severe, can get interstitial edema
    • if chronic, can get permanent interstitial fibrosis
  31. What are the causes of viral bronchitis in dogs and cats?
    • Dogs- tracheobronchitis
    • Cats- upper respiratory disease
    • [not usually seen radiographically unless complicated by bacterial infection]
  32. What are the pathological aspects of bronchiectasis?
    • loss of normal bronchial tapering
    • changes in bronchial epithelium, mucus characteristics, ciliary function--> these lead to predisposition for chronic bacterial infections
  33. It is common to have __________ with bronchiectasis because...
    chronic bacterial infections/ bronchopneumonia; changes in bronchial epithelium and mucociliary elevator.
  34. What are causes of diffuse hyperlucency on thoracic radiograph? (5)
    • overexposure
    • hypovolemia
    • air trapping
    • emphysema (usually accompanied by bronchial thickeing)
    • overinflation (increased tidal volume, upper airway obstruction, iatrogenic)
  35. What are causes of focal pulmonary mineralization? (6)
    • bronchial mineralization
    • pulmonary osteomas
    • granulomas
    • histoplasmosis
    • primary lung tumor
    • aspirated barium sulfate
  36. What are causes of diffuse pulmonary mineralization? (4)
    • hyperadrenocorticism (cushings)
    • hyperparathyroidism
    • chronic uremia
    • idiopathic
  37. How many radiographs are usually needed to make a complete thoracic series on an adult horse?
    usually 4
  38. Describe bacterial pneumonia in large animals. (4)
    • usually bilateral
    • ventral distribution most common
    • interstitial or alveolar pattern
    • abscesses/ granulomas more common than in small animals
  39. You see multiple, "fluffy" soft tissue opacity masses that are sometimes cavitated in the lungs of a foal; top differential?
    Rhodococcus pneumonia
  40. Describe COPD (heave's) in horses. (4)
    • Radiographic abnormalities only seen in advanced disease
    • air trapping- you can see this by making inspiration and expiration projections (will look the same because gas is not leaving the lungs, hence "trapped")
    • reticulated interstitial pattern
    • +/- bronchiectasis
  41. How does hypovolemia appear radiographically? (3)
    • pulmonary vessels very small
    • lack of vascular markings
    • microcardia
Card Set
Radiology2- Lung Diseases
vetmed radiology2