JC Block C - Diagnostic Radiology - Chest

Question 1

Label

Answer 1

Question 2

Label

Answer 2

Question 3

3 main vessel from aortic arch

Answer 3

1. Brachiocephalic trunk (right subclavian artery, right common carotid artery)
2. Left common carotid artery
3. Left subclavian artery

Question 4

Label

Answer 4

Question 5

Label

Answer 5

Oblique view:
 Oblique fissure (X-ray beam tangential to structure)
 Trachea (slopes backwards)
 Hilum
 Diaphragms

Question 6

Approach to CXR

• How to assess adequacy of CXR

Answer 6

1) Identify name and date of CXR (esp private films)
2) Identify R and L labels

3) Assess technical factors for adequacy:
a) Inspiration: 6 anterior ribs or 10 posterior ribs bisecting hemidiaphragm
 When counting posterior, note that the 1st rib is a ring

b) Rotation: medial ends of clavicles equidistant from vertebral spinous process = centrally positioned
c) Penetration: retrocardiac T-spine outline (see-through effect = adequate penetration)

Question 7

Evaluation checklist for anatomical structures seen on CXR

Answer 7

Check position of the trachea and mediastinum (central?)

Evaluation of lungs: Three zones:
 Upper (above anterior end of 2 nd rib)
 Middle (between 2nd & 4th ribs)
 Lower (below 4th rib)

Compare R and L lungs

Extrapulmonary evaluation
 Bony rib cage
 Scapulae and clavicle
 Supraclavicular fossa
 Axillary folds (masses)
 +/- breast shadows

Question 8

Areas for detailed review on CXR

- ABCDE

Answer 8

Review areas (mnemonic ABCDE):
 Apex (can have tumor, opacities)
 Behind the heart
 Cardiophrenic angles (should be acute)
 Costophrenic angles (pleural effusion)
 Diaphragm
 Edge of film

Question 9

Areas for detailed review on lateral CXR

Answer 9

 Retrocardiac window (occupied by lower lobe containing lung tissue, should be radiolucent)

 Retrosternal window (occupied by lung tissue, should be radiolucent)

 Diaphragms

 Clarity of vertebrae

 Posterior cardiac border

 Posterior costophrenic sulcus

Question 10

Causes of mediastinal and tracheal PULL

Answer 10

Ipsilateral (volume loss = pull)

 Collapse
 Fibrosis
 Surgery (pneumonectomy, lobectomy)

Fibrosis – radiological features:
 Opacification
 Ipsilateral tracheal deviation
 Ipsilateral elevation of hilum and diaphragm
(normally right hilum lower than left)

Question 11

Causes of mediastinal and trachea PUSH

Answer 11

Contralateral (mass effect = push)

 Large pleural effusion
 Tumours
 Pneumothorax

Question 12

Radiological features of pulmonary fibrosis

Answer 12

Fibrosis – radiological features:
 Opacification
 Ipsilateral tracheal deviation
 Ipsilateral elevation of hilum and diaphragm

Question 13

Radiological features of pleural effusion

Answer 13

 Ipsilateral opacification
 Contralateral tracheal deviation and mediastinal shift
 Note: small pleural effusion does not cause mas
effect

Question 14

Radiological features of pneumothorax

Answer 14

 Hyperlucent (no vascular lung markings)

If tension pneumothorax:
 Contralateral tracheal deviation and mediastinal shift
 Larger ipsilateral intercostal spaces
 Flattening of the ipsilateral diaphragm
 Slight depression of ipsilateral heart border

Question 15

Radiological features of lung consolidation

Answer 15

Alveoli are filled with dense material – could be:
 Pus (infection)
 Blood (hemorrhage)
 Fluid (pulmonary edema)
 Cancer cells

Radiological features:
 Denser lung compared to normal lung
 Air bronchograms: see tubular structure transversing
through consolidated lung

Question 16

Lesion

Answer 16

Cavitation – can be filled with:
 Air
 Air + fluid
 Soft tissue (e.g. fungal ball, tumor)

Question 17

Ddx Multiple small pulmonary nodules

Answer 17

 Infective: tuberculosis, fungal, viral

 Neoplastic: miliary metastatic lesions (e.g. thyroid cancer)

 Granulomatous: sarcoidosis (uncommon in HK)

 Autoimmune: granulomatosis with polyangiitis (formerly called Wegener’s granulomatosis), rheumatoid arthritis

 Occupational: pneumoconiosis

Question 18

If the left and right heart borders are abnormal, which lung segments are affected

Answer 18

Left heart border: Lingula segment

Right heart border: Right middle lobe

Question 19

2 modalities of CT for lungs

Compare thickness, spacing, resolution, indications

Answer 19

Question 20

6 modalities of lung imaging

Answer 20

CXR

CT thorax**

Ultrasound: Pleural effusion only

Nuclear scan: Ventilation/perfusion (V/Q) scan: to assess pulmonary embolism (mismatch)

PET/CT – lung cancer staging: staging, metastasis and pleural dissemination

MRI: Only for soft tissue invasion in Pancoast tumor

Question 21

Case 1:
 A young man with sudden pleuritic chest pain and dyspnea:
 Hyperlucent left hemithorax (no vascular lung markings)

Interpret

Answer 21

 Opacity overlaps with left heart wall – collapsed left lung
 Trachea and mediastinum shifted to the right
 Larger left intercostal spaces
 Flattening of the L diaphragm
 Slight depression of left heart border

> > > > Tension pneumothorax

Question 22

Case 2:
 Middle-aged lady with productive cough and fever:

Interpret

Answer 22

 Increased density (opacities) in right upper and middle zone
 Hazy and indistinct margin
 Air bronchograms

> > > Right upper lobe consolidation (consistent with pneumonia)

Question 23

Case 3:
 A 45 year-old lady, a chronic smoker, presents with cough and blood
stained sputum:

Interpret and Dx

Answer 23

 Dense triangular shadow behind the heart

 Loss of clarity of left hemidiaphragm so pathology should involve the left lower lobe

 Displacement of left hilum

Left lower lobe collapse, Suspect malignancy

Question 24

Case 3:
 A 55 year-old lady with sudden SOB:

Interpret and Dx

Answer 24

 Cardiomegaly
 Bilateral perihilar haze
 Upper lobe venous diversion

> > Pulmonary edema in heart failure

Question 25

Case 4:

 Heavy smoker presented with chest pain and haemoptysis:

Answer 25

 Thick-walled left upper lung mass

 Central lucency suspicious of central cavitation (look for air-fluid level)

 Tethering of left hemidparhgam suggests volume loss in left lower lobe

Cavitating left upper/mid-zone mass + suspicious of left lower lobe bronchogenic carcinoma (Opacity behind heart, sitting on diaphragm)

Question 26

Case 5:
 A 17-year old girl with chest pain:

Interpret and Dx

Answer 26

 Multiple dense nodules of variable size in both sides of her lung

DDx:
 Tuberculosis
 Lung metastases
 Autoimmune (Wegner’s granulomatosis)

Question 27

Case 6:
 A 68-year-old lady, smoker, presented with haemoptysis

Interpret and Dx

Answer 27

CXR:
 Right hilar mass (much bulkier than normal)
 Right pleural effusion
 Widened superior mediastinum
 Suspicious of primary lung carcinoma with malignant right pleural effusion
 Need CT thorax for further assessment

Question 28

Case 7:

 CXR of a woman with rheumatoid arthritis:

Answer 28

HRCT:
 Ground glass opacity on left
 Honeycombing (round cyst-like lesions prominent in lower zone) – irreversible, on right

Question 29

Case 8:
 66-year-old man with sudden pleuritic chest pain; recent long haul flight

Interpret and Dx

Answer 29

CXR:
 Wedge-shape peripehral consolidation in LLZ (doesn’t blur hemidiaphragm)
 Blunting of left costophrenic angle
 Suspicious of pulmonary embolism, pulmonary infarct

 CT pulmonary angiogram (CTPA) next to find emboli in pulmonary arteries, any wedge-shaped infarcts

Question 30

Case 9:
 Young lady who had a pre-employment CXR:

Interpret and Dx

Answer 30

 Extrapulmonary mass
 Pleural-based
 Paraspinal
 Vertebral/ disc disease

 Neurogenic lesions, likely Neurofibroma
if mediastinal lesion extends beyond clavicles (i.e. cervicothoracic sign), it has to be posterior

Cf. anterior: thyroid will not demonstrate cervicothoracic sign