1. Radiographic Assessment
Chapter 8
Radiographic Assessment

2. Introduction
Bedside CXR’s are most common (as opposed to taking the baby to the X-ray dept)
Viewed using picture-archiving and communication system (PACS); useful for quick assessment without radiologist interpretation
AP Frontal and lateral views most common

3. Indications
Identifying position of lines and tubes (OG, UVC, UAC, ETT…)
Visualizing lung fields; correlated with physical assessment
Post intubation, post surfactant delivery, sudden distress…
FBAO

4. Indications Air Leaks Pneumothorax Pneumomediastinum Pneumopericardium
Pneumoperitoneum
Subcutaneous emphysema
Pulmonary Interstitial Emphysema (PIE)
Air embolism

5. Causes of Air Leaks Over-vigorous resuscitation Intubation/IPPV/NCPAP
‘Fighting’ ventilator
High PIP
Long I.T
MAS; RDS; Pneumonia; Pulmonary hypoplasia; BPD; tachypnea

6. Radiographic Technique
Frontal
Lateral
Posteroanterior
Anteroposterior
Lateral decubitus
Forced expiratory-FBAO
Oblique
Fluoroscopy

7. Frontal AP

8. Right and Left Lateral

9. Lateral Decubitus

10. Lateral Decubitus
Useful in determining mobile pleural fluid and also to better identify a pneumothorax

11. Normal Chest Anatomy
Bone and metallic orthopedic hardwear appear bright white due to greater absorption of light
Air little absorption, less exposure on film, appears black
Soft tissue organs and fluid appear as shades of gray
Incorrect exposure alters normal gray scale, appear whiter if under exposed

12. Reading a CXR
An accurately positioned chest x-ray will demonstrate the lung apices, lung bases, medial and lateral lung fields, and the costophrenic angle of each lung. An air filled trachea is seen superimposed in the midline of the upper thoracic vertebrae. The heart silhouette should be seen without rotation and the lower thoracic vertebral bodies slightly transparent through the mediastinum.

13. Right clavicle (A)
Right scapula (B),
Right fourth anterior rib (C), right eighth rib (D),
Right costophrenic angle (E),
Left lung apex (F),
Aortic arch (G), hilum (H), heart (I),
left lung base (J), Right hemidiaphragm (white arrow).

14. Reading a CXR
The PA or AP chest radiograph displays a wide range of structures with many superimpositions having various radiographic densities. Furthermore, overlying mediastinal or bony structures may obscure portions of the lungs. Therefore, it is important that image quality be optimal and positioning accurate for diagnosis of subtle abnormalities.

15. Reading a CXR
Heart is composed of soft tissue of waterlike density, clearly demarcated by a distinct edge from adjacent air-filled lung
If the lung becomes waterlike from loss of air, atelectasis, filled with fluid/puss/PNA… the heart edge is no longer seen
Called a silhouette sign- two normal structures lose their distinct edge and blend together

16. PNA- Heart edge missing

17. Normal CXR good heart edge

19. ANATOMY Location Size & Placement
Lungs
Heart
Thymus
Vessels
Chest wall

20. H E A R T
Half the lateral diameter
Plumper in newborns

21. T H Y M U S

22. C H E S T

23. Reading a CXR AP view accentuates heart size
Pulmonary artery and veins form confluent areas on either side of the heart called the hila
Enlargement of the hila= increased pulmonary vessels or enlarged lymph nodes
Aortic Knob also seen
Mediastinum= heart, aorta, pulmonary branches, great vessels, thymus, vena cava

25. Close up of upper thorax in a patient with Coarctation of the Aorta
Close up of upper thorax in a patient with Coarctation of the Aorta. The red arrows point to rib notching caused by the dilated intercostal arteries. The yellow arrow points to the aortic knob, the blue arrow to the actual coarctation and the green arrow to the post-stenotic dilation of the descending aorta.

26. Normal CXR good heart edge

27. Good Technique
This is a good radiograph of the infant chest. Notice that the exposure technique adequately penetrates the thoracic vertebrae.
The head is straight so that the clavicles are not rotated. When performing a pediatric chest x-ray, it is important that the chest is not rotated. Structures such as the trachea should appear over the cervical and upper thoracic vertebrae. This is because the heart must be presented anatomically and its border with the thymus seen.
Good alignment can help identify abnormal anatomical shifts due to congenital disorders (e.g. tetrology of fallot, dextrocardia, etc).
Proper collimation was applied vertically to include the nasogastric tube (blue arrow) and umbilical catheter (red arrow). Overall, this is an excellently positioned and exposed chest x-ray. I would suggest that the proximal portion of the NG tube be moved upward in the future and chest lead moved from the lower lung field.

29. Critique?
At first glance this radiograph may appear to be acceptable; however it is not.
The main reason this radiograph should be repeated is motion artifact and quantum mottling. grainy image appearance (termed quantum mottling)
Notice that the vascular lung marking are ill defined and the bronchi are not aerated. This is because the exposure was taken on expiration. Generally, pediatric radiographers know to watch the inspiration indicator on the ventilator rather than the patient so that exposure is made on full inspiration.
When an infant is not on a ventilator the abdomen rises with inspiration and falls with expiration. The other issue is that the head is not in anatomic position, which causes a misrepresentation of the location of the tip of the endotrachael tube.

30. Critique Continued
Alignment of the part is lacking in all directions. While this critique does not normally reference the absence of a position marker it should be noted that this is a serious breach when imaging infants. Congenital variations such as dextrocardia, situs inversus, and others such as transposition syndromes are diagnosed because position markers alert the physician.

32. Obviously there is mild chest rotation, wire artifact, and poor vertical collimation of the chest.
These three radiographs show why it is important to carefully evaluate ventilated pediatric chest x-rays for motion artifact. On the left is the radiograph being evaluated. The middle radiograph shows the same chest x-ray in black bone window or what is called a positive image (black and whites are reversed). Notice that the lung markings are not seen on the middle radiograph. Compare this to the lung markings seen on the right radiograph. Observe how the lung markings and the heart are well defined on this radiograph. Also observe how motion artifact produces a faint heart shadow and lack of clear lung markings (middle radiograph). Now back to the original radiograph, which is a negative. Does motion artifact now stand out to you? When this radiograph is repeated turn the head to anatomical position, collimate vertically, and make the exposure at peak ventilator inspiration.

33. Case Study
A toddler was brought to the emergency department for increasing respiratory distress over the past few days. He has also had fevers, and was started on antibiotics by his family doctor with no improvement.
In the emergency department he had SaO2 of 89% and was treated with oxygen. Prominent wheeze, with decreased air entry and occasional crackles were noted, predominantly on the right-side of his chest. He showed no response to repeatedly nebulized bronchodilators.
Given this lack of response to therapy, chest radiographs were ordered:

34. A foreign body in the right main bronchus
A foreign body in the right main bronchus. There is atelectasis (collapse) predominantly affecting the right lower lobe (note the distinct right heart border on the AP film, and patchy opacities below the foreign body on the lateral film).

35. Round-shaped foods are the most frequently aspirated objects:
Peanuts, grapes, raisins, and hot dogs…
Nonfood objects include all sorts of items — such as metal dowels from Swedish furniture. Conformable objects are the most difficult to manage and remove. Balloons are the objects most likely to result in death.

36. FBAO
Large objects tend to lodge in the upper airway and trachea (about 20% of airway foreign bodies). They are likely to cause obvious and dramatic signs of upper airway obstruction such as dyspnea, drooling, stridor, and cyanosis — which may ultimately cause death unless expeditiously removed.
More common are smaller objects that pass through the subglottic space. They will usually lodge in a bronchus — usually the right main bronchus — or in a more terminal part of the airway.

37. FBAO Symptoms From the history:
Coughing or choking episodes while eating solid foods (classically nuts), or while sucking a small plastic toy or similar object. This history should never be dismissed — a foreign body is almost always present in the symptomatic child.
Persistent coughing and wheezing.
Delayed presentations may shows symptoms of infection due to secondary tracheitis, bronchitis, atelectasis or pneumonia.
If foreign body ingestion was unwitnessed, there may be no history of aspiration (about 15% of cases).
On examination there may be:
no physical signs
reduced breath sounds over all or part of one lung
Wheeze: beware of the sudden onset of a first wheezing episode in a toddler in whom there is no history of allergy, especially if it follows a choking episode.
Features of a secondary tracheitis, bronchitis, atelectasis or pneumonia if presentation is delayed

38. FBAO Chest radiographs may show: radio-opaque foreign bodies
obstructive hyperinflation (asymmetric)
collapse/ atelectasis
normal (15% of lower airway foreign body aspirations)
Some clinicians prefer full inspiration and full expiration films to check for hyperinflation (impossible in the uncooperative toddler). An alternative is to perform lateral decubitus films, looking for the absence of of decreased lung volume when the obstructed side is dependent. The films should include the nasopharynx to the chest.
A normal chest radiograph does not exclude the presence of a foreign body
Bronchoscopy is indicated for all patients with a suspected inhaled foreign body, even if the chest radiograph is ‘normal’ — unless the child is completely asymptomatic with a normal physical and radiographic examination.

39. Peanut Rule
rule -- children cannot eat peanuts if they are unable to touch their opposite ear by reaching over their head. Corresponds to about their fifth birthday

41. Silhouette Sign

42. Evaluating Normal Structure

43. Normal Thymus

44. Evaluating the Lungs Lungs Inspiration Trachea and mainstem bronchi
Lobes
Fissures
Inspiration
Trachea and mainstem bronchi

45. Positioning of Lines and Tubes
Endotracheal tubes
Between thoracic inlet and carina
Vascular catheters

46. Airway Obstruction

47. Airway Obstruction (cont.)

48. Airway Obstruction (cont.)

49. Respiratory Distress Syndrome

50. Pneumothorax

51. Incidence of Pneumothorax
1-1.5% of all newborns
Affects 5-14% of babies admitted to NICUs
Males > Females
Terms = Pre-terms
Spontaneous pneumothorax : 10/15,000
Bilateral in 10-21%
Mortality 20%

52. Clinical Presentation
Signs of respiratory distress: grunting, ↑RR, cyanosis/desaturation/respiratory acidosis
Apnea, bradycardia, ↓BP (obstructed shock)
Displaced apex beat
Change in breath sounds
↑Ventilatory requirements
All occur suddenly

53. Diagnosis Patient Assessment Tansillumination
CXR: Lateral decubitis, AP
Direct needle aspiration

55. Treatment Conservative therapy +/- 100% oxygen
If no underlying lung disease
No complicating therapy
No distress
No continuous air-leaks
Resolve in hrs
OXYHOOD, or NC at 100%

56. Treatment Needle aspiration Equipment 21-23 G butterfly needle
Cleaning solution
Syringe & 3-way tap
Procedure
Clean skin
Insert needle 2nd/3rd ICS MCL
End of tubing under water & watch for bubbles or
Apply continuous suction to syringe until rapid flow of air

58. Pneumomediastinum

59. Pulmonary Interstitial Emphysema

60. Meconium Aspiration Syndrome

61. Group B Streptococcal Pneumonia

62. Diaphragmatic Hernia

63. Atelectasis

64. Pneumonia

65. Cystic Fibrosis

66. Acute Respiratory Distress Syndrome

67. Chest Trauma

68. CDH

69. Hour long video on interpetation