1. Med Students Lecture Series Chest
University Hospitals Case Medical Center
Department of Radiology

2. Factors in evaluation for a technically adequate chest x-ray

3. Factors in evaluation for a technically adequate chest x-ray
Penetration
Inspiration
Rotation
Magnification
Angulation

4. Penetration
Should be able to faintly see the thoracic spine through the heart shadow
Underpenetration
Will not be able to see the spine through the heart
Introduced Errors
Left lung base may be opaque
Pulmonary markings may be more prominent
Overpenetration
Lung markings will seem decreased or absent

5. Penetration NORMAL UNDERPENETRATED OVERPENETRATED
NORMAL
UNDERPENETRATED
OVERPENETRATED

6. Inspiration Assess by counting the number of posterior ribs
Excellent inspiration – 10 posterior ribs
Hospitalized patients – 8 to 9 posterior ribs
Poor inspiration
Compresses and crowds the lung markings

7. Rotation Evaluate the medial end of each clavicle
Rotation may alter the contours of the heart, great vessels, hila and hemidiaphragm
NORMAL

8. Rotation

9. Magnification
The closer an object is to the surface being imaged, the more true to its actual size the resultant image will be
PA chest x-ray – heart is an anterior (closer to the imaging surface) – will be more true to size
AP chest x-ray – heart is posterior structure - magnified

10. Magnification

11. Angulation
X-ray beam should pass horizontally for an erect chest x-ray
Hospitalized patients - May not be able to sit upright
X-ray beam will be directed toward the patient’s head  APICAL LORDOTIC VIEW

12. Angulation

13. Factors in evaluation for a technically adequate chest x-ray
Penetration
Inspiration
Rotation
Magnification
Angulation

14. Basic Densities Conventional Radiography
Air
Fat
Fluid/Soft-Tissue
Calcium
Metal
NORMAL

15. Basic Densities Conventional Radiography
Air
Fat
Fluid/Soft-Tissue
Calcium
Metal
Air
NORMAL

16. Basic Densities Conventional Radiography
Air
Fat
Fluid/Soft-Tissue
Calcium
Metal
Fat
NORMAL

17. Basic Densities Conventional Radiography
Air
Fat
Fluid/Soft-Tissue
Calcium
Metal
Soft tissue
NORMAL

18. Basic Densities Conventional Radiography
Air
Fat
Fluid/Soft-Tissue
Calcium
Metal
Calcium
NORMAL

19. Basic Densities Conventional Radiography
Air
Fat
Fluid/Soft-Tissue
Calcium
Metal
Metal
NORMAL

20. Opacified Hemithorax Large pleural effusion Atelectasis Pneumonia
of the entire lung
Pneumonia
of an entire lung
Pneumonectomy

21. Mediastinal Shift – Right sided hemithorax
Opacified Hemithorax
Mediastinal Shift – Right sided hemithorax
Heart
Trachea
Right Hemidiaphram
Pleural Effusion
Leftward
Left
Disappears
Pneumonia
No shift
Midline
May disappear
Atelectasis
Rightward
Right
Upward
Pneumonectomy

22. Pleural Effusion Transudative Exudative Congestive Heart Failure
Hypoalbuminemia
Cirrhosis
Nephrotic Syndrome
Empyema
pus
Hemothorax
fluid hematocrit > 50% blood
Chylothorax
increased TG or cholesterol

23. Pleural Effusion Different Appearances of Pleural Effusions
Subpulmonic Effusion
Blunting of the Costophrenic Angles
The Meniscus Sign
Loculated Effusions
Fissural Pseudotumors
Laminar Effusions
Hydropneumothorax

24. Pleural Effusion Subpulmonic Effusion
Free flowing - Below the diaphragm
Frontal – highest point of the hemidiaphragm is displaced laterally
Lateral – curved hemidiaphragm has an abrupt change when it meets the major fissure – becomes flat anteriorly

25. BLUNTING OF THE COSTOPHRENIC ANGLE
Pleural Effusion
BLUNTING OF THE COSTOPHRENIC ANGLE
Normal Amount of Pleural fluid – 2 to 10mL fluid
Lateral Projection – Posterior Costophrenic Angle – 75mL fluid
Frontal Projection – Lateral Costophrenic Angle – 300mL fluid

26. Pleural Effusion MENISCUS SIGN
Pleural fluid appears to rise higher along the edges of the thorax
Meniscus Shape medially and laterally  Upside down “U”

27. Pleural Effusion LOCULATED EFFUSIONS
Result of limited mobility of the pleural effusion
often by adhesions old empyema or hemothorax
Unusual shapes – do not change appearance with changing positions
Difficult to drain non communicating pockets

28. FISSURAL PSUEDOTUMORS
Pleural Effusion
FISSURAL PSUEDOTUMORS
Sharply marginated collections of pleural fluid  Lenticular shape
Interlobar pulmonary fissure – minor fissure is the most common
Subpleural location
Not free-flowing

29. Pleural Effusion LAMINAR EFFUSIONS NORMAL EFFUSION
Thin band-like density along the lateral chest wall
Near costophrenic angle
Not free-flowing

30. Pleural Effusion HYDROPNEUMOTHORAX
Both Air (Pneumothorax) and Fluid in the Pleural space
Air-Fluid Level
Etiology – Trauma, Surgery, Bronchopleural Fistula

31. Pneumonia Consolidation of the lung produced by inflammatory exudate
General Characteristic - More dense than surrounding aerated lung
Patterns:
Lobar
Segmental
Interstitial
Round
Cavitary

32. Pneumonia Lobar pneumonia
Prototype – pneumococcal pneumonia: Streptococcus pneumoniae
Homogeneous consolidation of affected lobe with air bronchograms
Sharp margins at the edge of a lobe – interlobar fissure
Silhouette sign – where consolidation contacts heart, aorta, or diaphragm

33. Pneumonia SEGMENTAL pneumonia
Prototype – bronchopneumonia – Staphylococcus aureus
Spreads via the tracheobronchial trachea
Patchy airspace disease – involving several segments simultaneously
Margins are fluffy and indistinct, No air-bronchograms

34. INTERSTITIAL pneumonia
Prototype – Viral pneumonia
Mycoplasma pneumonia, Pneumocystis (AIDS)
Involves airway walls and alveolar septa - Reticular interstitial disease
Diffuse spread throughout the lungs

35. Pneumonia ROUND pneumonia
Mostly children – Haemophilus influenzae, Streptococcus, Pneumococcus
Spherical shape – may resemble a mass
Lower lobes

36. Pneumonia CAVITARY pneumonia
Prototype – Mycobacterium tuberculosis
Other organisms – Stahylococcal pneumonia, Klebsiella, Coccidiodomycosis
Usually occurs with post primary TB – reactivation TB
upper lobe predominance, thin-walled, no air-fluid levels

37. Pneumothorax
Air within the pleural space – between the parietal and visceral pleura
Types
Simple
no shift of mediastinal structures
Tension
shift of mediastinum AWAY from pneumothorax cardiopulmonary compromise
Causes
Spontaneous
Rupture of an apical, subpleural bleb or bulla
Tall, thin males – ages 20-40
Traumatic
Traumatic or iatrogenic

38. Pneumothorax Signs Visualization of the visceral pleural line
Convex curve of the visceral pleural line
Paralleling the contour of the chest wall
Absence of lung marking
Beyond the visceral pleural line
Deep sulcus sign
Air-fluid level in the pleural space
Hydropneumothorax  previously discussed

39. Pneumothorax Visible visceral pleural line
Convex visceral pleural line
Absence of lung markings

40. Pneumothorax Deep sulcus sign Important for supine films

41. Please read the supplemental article on mediastinal masses
Questions?
Please read the supplemental article on mediastinal masses
Chest quiz will be administered on Thursday at 11:30AM before conference
Major Text Reference for Power Point:
Learning Radiology: Recognizing the Basics
By William Herring