Radiography Exam Anatomy and Pathology for Radiographers 1 — Questions and Answers
Question 1: On a PA chest radiograph, the right heart border is primarily formed by which cardiac structure?
- Right atrium (Correct answer)
- Right ventricle
- Left atrium
- Superior vena cava
Correct answer: Right atrium
On a PA chest radiograph, the right heart border is formed primarily by the right atrium in its lower portion, with the superior vena cava (SVC) forming the upper right border.
On a PA chest radiograph: Right heart border (top to bottom) = SVC (upper) → right atrium (lower). Left heart border (top to bottom) = aortic knuckle → pulmonary trunk → left atrial appendage → left ventricle. The right ventricle is mostly anterior and does not form the standard chest X-ray borders. Left atrium enlargement causes prominence of the left heart border mid-segment. These landmarks are essential for identifying cardiac chamber enlargement.
Question 2: Which radiographic sign describes the sharply defined density of a lung consolidation that stops abruptly at a lobar fissure, indicating lobar pneumonia?
- Air bronchogram sign
- Silhouette sign
- Lobar consolidation with fissure boundary (Correct answer)
- Hampton's hump
Correct answer: Lobar consolidation with fissure boundary
Lobar consolidation stopping sharply at an interlobar fissure is the hallmark of lobar pneumonia — the sharp border is created by the fissure acting as an anatomic boundary for the infection.
Lobar pneumonia produces complete homogeneous opacification of an entire lobe, sharply bounded by the interlobar fissures. The most common cause is Streptococcus pneumoniae. Air bronchograms (air-filled bronchi visible within the opacity) are frequently seen. The silhouette sign (loss of the normal interface between a structure and adjacent lung) helps identify which lobe is affected (e.g., right middle lobe consolidation obliterates the right heart border). Hampton's hump is a wedge-shaped pleural-based opacity in pulmonary embolism.
Question 3: On a lateral lumbar spine radiograph, which structures are identified at the L4-L5 intervertebral disc level?
- The intervertebral disc space between the fourth and fifth lumbar vertebral bodies and the posterior elements (Correct answer)
- The sacroiliac joint
- The femoral heads
- The intervertebral foramina of thoracic vertebrae
Correct answer: The intervertebral disc space between the fourth and fifth lumbar vertebral bodies and the posterior elements
The lateral lumbar spine radiograph demonstrates the L4-L5 disc space between the fourth and fifth lumbar vertebral bodies, surrounded by the vertebral endplates and posterior elements.
On lateral lumbar spine radiography, the L4-L5 intervertebral disc is the second most mobile and commonly herniated disc in the lumbar spine. The lateral view shows: vertebral body height, disc space width, posterior elements (pedicles, lamina, spinous processes), and the neural foramina (seen in oblique views). L4-L5 disc height loss, endplate irregularities, or loss of lumbar lordosis may indicate degeneration. The sacrum (S1) is the lowest visible segment on a standard lateral lumbar view.
Question 4: The 'air bronchogram sign' on a chest radiograph is significant because it indicates:
- Air-filled bronchi visible within an area of lung consolidation, confirming the consolidation is air-space (alveolar) disease (Correct answer)
- A pneumothorax tracking along a bronchus
- Dilated, air-filled bronchioles in emphysema
- Air within the pleural space
Correct answer: Air-filled bronchi visible within an area of lung consolidation, confirming the consolidation is air-space (alveolar) disease
Air bronchograms are visible because surrounding alveoli are fluid-filled (consolidated) while bronchi remain air-filled, creating contrast. This confirms alveolar consolidation rather than pleural or atelectatic disease.
Air bronchograms occur when airway lumens (bronchi and bronchioles) remain air-filled while the surrounding alveoli fill with fluid, exudate, or cells. This sign is positive in consolidative processes: bacterial pneumonia, pulmonary edema, pulmonary infarction, and bronchoalveolar carcinoma. It is typically absent in atelectasis caused by bronchial obstruction (where the bronchus itself is blocked). Air bronchograms help differentiate airspace disease from pleural effusion or chest wall lesions.
Question 5: Increased radiodensity (opacity) seen on a plain film radiograph in a region of bone indicates:
- Sclerosis — increased bone density that can be seen in osteoblastic metastases, Paget's disease, or healing fractures (Correct answer)
- Lytic destruction of bone
- Normal cortical bone
- Osteoporosis
Correct answer: Sclerosis — increased bone density that can be seen in osteoblastic metastases, Paget's disease, or healing fractures
Increased radiodensity (whiteness) in bone represents sclerosis — increased calcium deposition or trabecular thickening — seen in osteoblastic processes like prostate cancer metastases, Paget's disease, and bone healing.
On plain film radiography, bone density reflects calcium content. Sclerotic (dense) bone appears white/opaque and results from osteoblastic activity (bone formation). Common causes: osteoblastic metastases (prostate, breast), Paget's disease, bone islands (enostoses), stress fractures in healing phase, and osteoma. Lytic (destructive) lesions appear dark/lucent (osteoclastic activity). Mixed sclerotic-lytic lesions occur in Paget's disease and some metastases. Osteoporosis shows decreased overall bone density.
Question 6: The 'silhouette sign' on a chest radiograph is used to:
- Localize a lung opacity by identifying loss of normal interface between the opacity and an adjacent structure (heart, diaphragm) (Correct answer)
- Identify pneumothorax by the absence of lung markings
- Detect pleural effusion by blunting of the costophrenic angle
- Evaluate aortic size in the mediastinum
Correct answer: Localize a lung opacity by identifying loss of normal interface between the opacity and an adjacent structure (heart, diaphragm)
The silhouette sign localizes disease — when an opacity is in contact with a normally visible structure (e.g., right heart border), the interface disappears, indicating the disease is in the adjacent lung lobe.
The silhouette sign (Felson's sign): two structures of equal radiographic density in contact share no visible border. Example: right middle lobe consolidation → right heart border obscured (silhouetted); right lower lobe consolidation → right hemidiaphragm silhouetted but right heart border preserved. Uses: localizes which lobe is consolidated, helps differentiate mediastinal from lung masses, identifies anterior vs. posterior lesions. The sign requires the two structures to be truly adjacent — not separated by air-containing lung.
Radiography Exam Anatomy and Pathology for Radiographers 1
On a PA chest radiograph, the right heart border is primarily formed by which cardiac structure?