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Arab Board Radiology Final Written study materials
Arab Board Radiology Final Written study resources

Arab Board Radiology Final Written practice questions

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Question 1Neuroradiology (brain, spine, head and neck)

A 55-year-old man presents with sudden severe headache. Non-contrast CT shows hyperdensity in the basal cisterns and Sylvian fissures. What is the most likely diagnosis?

  1. Acute subarachnoid hemorrhage Correct answer.
  2. Acute ischemic infarct
  3. Chronic subdural hematoma
  4. Epidural hematoma

Explanation

Acute hemorrhage appears hyperdense on non-contrast CT, and blood pooling in basal cisterns and Sylvian fissures is the classic pattern of subarachnoid hemorrhage, most often from a ruptured berry aneurysm.

Question 2Neuroradiology (brain, spine, head and neck)

Which imaging sequence best detects acute infarction within the first few hours of symptom onset?

  1. Non-contrast CT
  2. T1-weighted imaging
  3. T2-weighted imaging
  4. Diffusion-weighted imaging Correct answer.

Explanation

Diffusion-weighted imaging shows restricted diffusion (hyperintense with low ADC) within minutes of cytotoxic edema, making it the most sensitive early sequence for acute infarction.

Question 3Neuroradiology (brain, spine, head and neck)

A patient has a biconvex hyperdense extra-axial collection in the temporal region with midline shift. This appearance most strongly suggests which diagnosis?

  1. Epidural hematoma Correct answer.
  2. Subdural hematoma
  3. Subarachnoid hemorrhage
  4. Intraparenchymal hemorrhage

Explanation

Epidural hematomas are biconvex (lens-shaped) because they are bounded by cranial sutures where the dura is tightly adherent, and they are commonly arterial in origin, often from the middle meningeal artery.

Question 4Neuroradiology (brain, spine, head and neck)

Which finding on MRI is characteristic of an acute demyelinating plaque in multiple sclerosis?

  1. Wedge-shaped cortical infarct
  2. Homogeneous calcified mass
  3. Cystic lesion with complete thin ring enhancement
  4. Ovoid periventricular lesion with incomplete ring enhancement Correct answer.

Explanation

Acute MS plaques are typically ovoid, periventricular, oriented perpendicular to the ventricles, and may show open-ring (incomplete) enhancement reflecting active inflammation at the advancing edge.

Question 5Neuroradiology (brain, spine, head and neck)

A 30-year-old woman has sudden thunderclap headache and CT shows subarachnoid hemorrhage. Which vascular imaging modality is the initial non-invasive test of choice to identify an aneurysm?

  1. CT angiography Correct answer.
  2. Carotid Doppler ultrasound
  3. MR venography
  4. Digital subtraction angiography

Explanation

CT angiography is the first-line non-invasive test for detecting intracranial aneurysms after subarachnoid hemorrhage, with high sensitivity and rapid acquisition. Conventional digital subtraction angiography remains the reference standard and is used when CTA is negative or for treatment planning.

Question 6Neuroradiology (brain, spine, head and neck)

Which sign on MRI indicates chronic rather than acute spinal cord compression?

  1. Epidural mass with cord displacement
  2. Focal cord signal change with atrophy and myelomalacia Correct answer.
  3. Nerve root enhancement
  4. Cord edema with T2 hyperintensity

Explanation

Chronic compression leads to cord atrophy and myelomalacia, seen as T2 hyperintensity with volume loss and sometimes T1 hypointensity, reflecting irreversible gliosis rather than reversible edema.

Question 7Neuroradiology (brain, spine, head and neck)

An infant presents with macrocephaly and a cystic posterior fossa mass communicating with the fourth ventricle, with cerebellar vermis hypoplasia. What is the most likely diagnosis?

  1. Arachnoid cyst of the middle cranial fossa
  2. Dandy-Walker malformation Correct answer.
  3. Aqueductal stenosis
  4. Chiari II malformation

Explanation

Dandy-Walker malformation is characterized by cystic dilatation of the fourth ventricle, hypoplasia or agenesis of the cerebellar vermis, and an enlarged posterior fossa with torcular elevation.

Question 8Neuroradiology (brain, spine, head and neck)

Which imaging finding is most specific for pituitary apoplexy?

  1. Hemorrhage or infarction within an enlarged pituitary gland Correct answer.
  2. Empty sella
  3. Diffuse pituitary enhancement
  4. Microadenoma smaller than 5 mm

Explanation

Pituitary apoplexy results from acute hemorrhage or infarction into a pituitary adenoma, producing a non-enhancing or hemorrhagic sellar mass, often with headache, visual loss, and endocrine dysfunction.

Question 9Neuroradiology (brain, spine, head and neck)

A patient with known lung carcinoma develops multiple ring-enhancing cerebral lesions at the gray-white junction with surrounding edema. What is the most likely diagnosis?

  1. Multiple sclerosis
  2. Brain metastases Correct answer.
  3. Primary glioblastoma
  4. Cerebral abscess

Explanation

Multiple enhancing lesions at the gray-white junction with extensive edema in a patient with a known primary malignancy strongly suggest hematogenous metastases.

Question 10Neuroradiology (brain, spine, head and neck)

Which MRI finding distinguishes an epidermoid cyst from an arachnoid cyst in the cerebellopontine angle?

  1. CSF-like signal on T2
  2. Smooth margins
  3. Restricted diffusion on DWI Correct answer.
  4. Absence of enhancement

Explanation

Epidermoid cysts show restricted diffusion (bright on DWI, low on ADC) because of keratinaceous contents, whereas arachnoid cysts follow CSF and do not restrict diffusion.

Question 11Neuroradiology (brain, spine, head and neck)

A patient with a spinal arteriovenous malformation is best evaluated for venous congestion of the cord using which finding on MRI?

  1. Serpiginous flow voids on the cord surface with T2 hyperintensity Correct answer.
  2. Vertebral body hemangioma
  3. Focal disc herniation with nerve root compression
  4. Syrinx without flow voids

Explanation

Spinal vascular malformations produce enlarged perimedullary flow voids and cord edema from venous congestion, which is the hallmark of venous hypertensive myelopathy.

Question 12Neuroradiology (brain, spine, head and neck)

Which finding on CT best indicates an acute ischemic stroke with a large vessel occlusion suitable for thrombectomy?

  1. Calcified choroid plexus
  2. Hyperdense middle cerebral artery sign Correct answer.
  3. Old lacunar infarct
  4. Enlarged ventricles

Explanation

The hyperdense MCA sign reflects thrombus in the proximal middle cerebral artery and suggests large vessel occlusion, supporting endovascular therapy decisions when combined with clinical and perfusion data.

Question 13Neuroradiology (brain, spine, head and neck)

Which imaging modality is the reference standard for detecting acute cervical spine fracture in a trauma patient with focal neurologic deficit?

  1. CT of the cervical spine Correct answer.
  2. MRI of the cervical spine
  3. Ultrasound of the neck
  4. Plain radiography

Explanation

CT is the reference standard for detecting acute cervical spine fractures in trauma because of its high sensitivity, speed, and ability to show bony detail and alignment.

Question 14Neuroradiology (brain, spine, head and neck)

A 45-year-old man has progressive bilateral sensorineural hearing loss and bilateral vestibular schwannomas. Which diagnosis should be considered?

  1. Tuberous sclerosis
  2. Neurofibromatosis type 2 Correct answer.
  3. Sturge-Weber syndrome
  4. Neurofibromatosis type 1

Explanation

Bilateral vestibular schwannomas are the hallmark of neurofibromatosis type 2, an autosomal dominant disorder caused by NF2 gene mutation on chromosome 22.

Question 15Neuroradiology (brain, spine, head and neck)

Which finding on temporal bone CT is characteristic of otosclerosis?

  1. Enlarged vestibular aqueduct
  2. Lucency around the cochlea (cochlear otospongiosis) Correct answer.
  3. Erosion of the scutum
  4. Soft tissue mass in the middle ear

Explanation

Otosclerosis produces areas of demineralization (otospongiosis) in the otic capsule, often seen as a lucent halo around the cochlea, and may cause fixation of the stapes footplate.

Question 16Neuroradiology (brain, spine, head and neck)

A patient presents with a rapidly enlarging neck mass and stridor. CT shows a well-defined cystic mass at the angle of the mandible that displaces the airway. Which diagnosis is most likely in an adult?

  1. Second branchial cleft cyst Correct answer.
  2. Laryngocele
  3. Thyroglossal duct cyst
  4. Ranula

Explanation

Second branchial cleft cysts occur at the angle of the mandible anterior to the sternocleidomastoid muscle and can enlarge and cause mass effect, including airway displacement.

Question 17Neuroradiology (brain, spine, head and neck)

Which pattern of enhancement is characteristic of a cerebral abscess on post-contrast MRI?

  1. Complete thin ring enhancement Correct answer.
  2. Incomplete open-ring enhancement
  3. No enhancement
  4. Homogeneous nodular enhancement

Explanation

Cerebral abscesses typically show a complete, thin, smooth enhancing rim, often with restricted diffusion in the central necrotic cavity.

Question 18Neuroradiology (brain, spine, head and neck)

Which imaging feature most reliably differentiates a vestibular schwannoma from a meningioma in the internal auditory canal?

  1. Extension into the internal auditory canal with widening of the porus acusticus Correct answer.
  2. Homogeneous enhancement
  3. Hyperostosis of adjacent bone
  4. Broad dural tail

Explanation

Vestibular schwannomas characteristically extend into and widen the internal auditory canal, whereas meningiomas typically arise from the dura and may show a dural tail or hyperostosis.

Question 19Neuroradiology (brain, spine, head and neck)

A patient with a known primary tumor develops a solitary enhancing spinal cord lesion. Which imaging feature suggests an intramedullary metastasis rather than a primary cord tumor?

  1. Dorsal column T2 hyperintensity only
  2. Eccentric exophytic cord mass
  3. Well-circumscribed cyst with mural nodule
  4. Multiple small enhancing intramedullary nodules with extensive edema Correct answer.

Explanation

Intramedullary metastases often appear as one or more small enhancing nodules within the cord with disproportionate surrounding edema, in a patient with known systemic malignancy.

Question 20Neuroradiology (brain, spine, head and neck)

Which finding on CT of the head suggests raised intracranial pressure in a patient with a large hemispheric infarct?

  1. Enlarged temporal horns only
  2. Hyperdense MCA sign
  3. Midline shift with effacement of the basal cisterns Correct answer.
  4. Calcification of the pineal gland

Explanation

Mass effect from a large infarct causes midline shift and effacement of the basal cisterns and sulci, which are signs of raised intracranial pressure and impending herniation.

Question 21Neuroradiology (brain, spine, head and neck)

Which sequence is most useful for detecting leptomeningeal carcinomatosis?

  1. Non-contrast T1-weighted imaging
  2. Susceptibility-weighted imaging
  3. T2-weighted imaging
  4. Post-contrast T1-weighted imaging with fat suppression Correct answer.

Explanation

Leptomeningeal tumor spread enhances along the pia and arachnoid, so thin-section post-contrast T1-weighted imaging with fat suppression is the most sensitive sequence.

Question 22Neuroradiology (brain, spine, head and neck)

A 60-year-old presents with progressive myelopathy and MRI shows T2 hyperintensity in the dorsal columns of the cervical cord. Which cause should be considered?

  1. Amyotrophic lateral sclerosis
  2. Syringomyelia
  3. Anterior spinal artery infarct
  4. Vitamin B12 deficiency Correct answer.

Explanation

Subacute combined degeneration from vitamin B12 deficiency classically affects the dorsal columns and corticospinal tracts, producing T2 hyperintensity in the posterior cord.

Question 23Neuroradiology (brain, spine, head and neck)

Which finding on MRI of the brain is most consistent with normal pressure hydrocephalus?

  1. Asymmetric temporal horn enlargement
  2. Ventriculomegaly with tight high-convexity sulci and enlarged Sylvian fissures Correct answer.
  3. Periventricular restricted diffusion
  4. Ventriculomegaly with generalized sulcal prominence

Explanation

Normal pressure hydrocephalus shows ventriculomegaly with disproportionately enlarged Sylvian fissures and tight high-convexity and medial parasagittal sulci, reflecting altered CSF dynamics.

Question 24Neuroradiology (brain, spine, head and neck)

Which imaging finding is characteristic of an acute vertebral compression fracture due to osteoporosis on MRI?

  1. Epidural soft tissue mass
  2. Band-like marrow edema with preserved posterior cortex Correct answer.
  3. Posterior element destruction
  4. Low T1 and low T2 signal without edema

Explanation

Acute osteoporotic compression fractures show marrow edema (T1 hypointense, T2/STIR hyperintense) in the compressed body with an intact posterior cortex and no posterior element involvement.

Question 25Neuroradiology (brain, spine, head and neck)

A patient with a slow-growing skull base tumor shows a "dural tail" and hyperostosis of the adjacent bone. What is the most likely diagnosis?

  1. Schwannoma
  2. Chordoma
  3. Epidermoid cyst
  4. Meningioma Correct answer.

Explanation

Meningiomas commonly arise from the dura and produce a dural tail and reactive hyperostosis of adjacent bone, features that help distinguish them from other skull base tumors.

Question 26Neuroradiology (brain, spine, head and neck)

A 28-year-old woman presents with sudden severe headache. Non-contrast CT shows diffuse hyperdensity in the basal cisterns and sulci. Which diagnosis is most likely?

  1. Acute subarachnoid hemorrhage Correct answer.
  2. Epidural hematoma
  3. Cerebellar infarction
  4. Chronic subdural hematoma

Explanation

Acute hemorrhage appears hyperdense on non-contrast CT, and blood layering in the basal cisterns and sulci is the classic pattern of subarachnoid hemorrhage, often from a ruptured aneurysm. The sudden severe headache also fits this presentation.

Question 27Neuroradiology (brain, spine, head and neck)

A 55-year-old man has a history of treated melanoma and now presents with a seizure. MRI shows a hemorrhagic mass at the gray-white junction with surrounding vasogenic edema. Which feature most favors metastasis over a primary glioma?

  1. Cortical thickening with blurring of the gray-white junction
  2. Midline shift with effacement of the lateral ventricle
  3. Extensive T2 hyperintensity tracking along white matter tracts
  4. Multiple lesions at the gray-white junction with a hemorrhagic component Correct answer.

Explanation

Metastases characteristically arise at the gray-white junction where tumor emboli lodge, and melanoma metastases are prone to hemorrhage. Multiplicity and this location strongly favor metastatic disease over a primary glioma.

Question 28Neuroradiology (brain, spine, head and neck)

A 70-year-old woman has sudden-onset vertigo, vomiting, and gait instability. Diffusion-weighted MRI shows restricted diffusion in the inferior cerebellar hemisphere. Which vascular territory is most likely involved?

  1. Posterior inferior cerebellar artery Correct answer.
  2. Recurrent artery of Heubner
  3. Anterior spinal artery
  4. Anterior choroidal artery

Explanation

The posterior inferior cerebellar artery supplies the inferior cerebellum and lateral medulla, and its occlusion produces vertigo, ataxia, and cerebellar infarction. Restricted diffusion on DWI confirms acute ischemia in that territory.

Question 29Neuroradiology (brain, spine, head and neck)

A 6-month-old infant has a large head and a cystic posterior fossa mass that communicates with the fourth ventricle, with cerebellar vermian hypoplasia. Which diagnosis is most likely?

  1. Arachnoid cyst of the posterior fossa
  2. Chiari II malformation
  3. Epidermoid cyst
  4. Dandy-Walker malformation Correct answer.

Explanation

Dandy-Walker malformation is defined by cystic dilatation of the fourth ventricle with vermian hypoplasia and an enlarged posterior fossa, often with hydrocephalus and macrocephaly. Communication of the cyst with the fourth ventricle is a key feature.

Question 30Neuroradiology (brain, spine, head and neck)

A 62-year-old man presents with progressive leg weakness and sensory loss. MRI shows a longitudinally extensive T2 hyperintense cord lesion over several segments with patchy enhancement. Which finding best supports a diagnosis of neuromyelitis optica spectrum disorder over multiple sclerosis?

  1. Lesion extending over three or more vertebral segments in the cervical cord Correct answer.
  2. Predominantly gray matter involvement of the cerebral cortex
  3. Small peripheral cord lesion less than one segment in length
  4. Presence of Dawson's fingers on sagittal brain MRI

Explanation

Neuromyelitis optica spectrum disorder characteristically produces longitudinally extensive transverse myelitis spanning three or more vertebral segments, often with central cord involvement. Multiple sclerosis typically causes short-segment peripheral cord lesions.

Question 31Thoracic Imaging

On a standard PA chest radiograph, the normal hilar shadow on the left is situated at a level relative to the right hilum that is best described as:

  1. At exactly the same level
  2. Lower than the right hilum
  3. Variable, with no consistent relationship
  4. Higher than the right hilum Correct answer.

Explanation

The left hilum normally lies slightly higher than the right because the left pulmonary artery arches over the left main bronchus, whereas the right pulmonary artery lies anterior to and below the right main bronchus. Loss of this normal relationship (e.g., a low left hilum) suggests volume loss or a mass.

Question 32Thoracic Imaging

A 30-year-old tall thin man presents with sudden pleuritic chest pain. The chest radiograph shows a thin visceral pleural line with no lung markings peripheral to it at the apex. The most appropriate immediate management is:

  1. CT-guided biopsy
  2. Intravenous antibiotics
  3. Observation with supplemental oxygen Correct answer.
  4. Tube thoracostomy

Explanation

A small primary spontaneous pneumothorax in a stable patient without significant symptoms can be managed conservatively with observation and oxygen, which accelerates resorption. Intervention is reserved for large, symptomatic, or expanding pneumothoraces.

Question 33Thoracic Imaging

The silhouette sign on a frontal chest radiograph is best explained by which principle?

  1. Increased density of a structure due to calcification
  2. Displacement of a fissure due to volume loss
  3. Loss of the border between two structures of similar radiographic density that are in contact Correct answer.
  4. Air trapping distal to a bronchial obstruction

Explanation

The silhouette sign occurs when two structures of the same radiographic density lie adjacent to each other, so their shared border is no longer visible. This allows localization of an opacity to a specific lobe or compartment.

Question 34Thoracic Imaging

Which radiographic feature most reliably distinguishes a large hiatal hernia from a lung abscess in the lower chest?

  1. Surrounding consolidation
  2. Presence of an air-fluid level
  3. An air-fluid level within a structure containing a gastric fold pattern and located behind the heart Correct answer.
  4. Increased density of the lesion on expiration

Explanation

A hiatal hernia contains stomach and therefore may show a retrocardiac air-fluid level with visible gastric mucosal folds; an air-fluid level alone is nonspecific and can occur in abscess or cavitation. Recognizing the gastric fold pattern and characteristic location supports the diagnosis.

Question 35Thoracic Imaging

A patient with a known right lower lobe pneumonia has a chest radiograph in which the right hemidiaphragm border is obscured. The opacity is most likely located in which lobe segment?

  1. Right lower lobe Correct answer.
  2. Right middle lobe
  3. Left lingula
  4. Right upper lobe

Explanation

The right hemidiaphragm is in contact with the right lower lobe, so consolidation of the lower lobe silhouettes the diaphragmatic border. The right heart border, by contrast, is silhouetted by middle lobe disease.

Question 36Thoracic Imaging

On a high-resolution CT, which pattern is most characteristic of usual interstitial pneumonia (UIP)?

  1. Diffuse ground-glass opacity with centrilobular nodules
  2. Upper-lobe-predominant consolidation with air bronchograms
  3. Bilateral lower-lobe subpleural honeycombing with traction bronchiectasis Correct answer.
  4. Mosaic attenuation with air trapping on expiration

Explanation

The UIP pattern is defined by basal, subpleural, peripheral-predominant reticulation, honeycombing, and traction bronchiectasis with minimal ground-glass change. This pattern underlies idiopathic pulmonary fibrosis.

Question 37Thoracic Imaging

A central pulmonary mass causing obstruction of the right main bronchus produces which combination of radiographic findings?

  1. Bilateral hyperinflation with flattening of the diaphragm
  2. Ipsilateral volume loss with mediastinal shift toward the lesion Correct answer.
  3. Unilateral hyperlucency with no mediastinal shift
  4. Ipsilateral hyperinflation with mediastinal shift away from the lesion

Explanation

Complete bronchial obstruction leads to resorption of distal air, atelectasis, and volume loss that pulls the mediastinum toward the affected side. Air trapping with shift away occurs only with partial ball-valve obstruction.

Question 38Thoracic Imaging

The most common cause of a solitary pulmonary nodule that is a benign calcified granuloma is best identified by which pattern of calcification?

  1. Amorphous punctate calcification throughout the nodule
  2. Eccentric stippled calcification
  3. Rim calcification only
  4. Central, laminated, or popcorn calcification Correct answer.

Explanation

Benign patterns of calcification include central, laminated, diffuse solid, and popcorn (chondroid) types, which indicate granuloma or hamartoma. Eccentric or stippled calcification is more concerning for malignancy.

Question 39Thoracic Imaging

Which finding on a chest radiograph most strongly suggests left atrial enlargement?

  1. Loss of the right heart border
  2. Double right heart border and splaying of the carina Correct answer.
  3. Elevation of the left hemidiaphragm
  4. Widening of the right paratracheal stripe

Explanation

Left atrial enlargement produces a double right heart border as the enlarged atrium projects to the right, and splaying of the carinal angle from bronchial elevation. These are classic signs of mitral valve disease.

Question 40Thoracic Imaging

A patient with acute pulmonary embolism has a chest radiograph that is often normal, but which classic sign may be seen?

  1. Air bronchograms in the upper lobes
  2. Hampton's hump, a peripheral wedge-shaped opacity Correct answer.
  3. Cavitation within the affected segment
  4. Kerley B lines

Explanation

Hampton's hump is a peripheral, wedge-shaped opacity representing pulmonary infarction in the setting of embolism. It is relatively uncommon, and the radiograph is frequently normal.

Question 41Thoracic Imaging

Which high-resolution CT finding is most specific for bronchiectasis?

  1. Signet-ring sign with bronchial dilatation and lack of tapering Correct answer.
  2. Mosaic attenuation on inspiration
  3. Bronchial wall thickening alone
  4. Centrilobular ground-glass nodules

Explanation

Bronchiectasis is diagnosed when a bronchus is dilated relative to its accompanying artery (signet-ring sign) and fails to taper toward the periphery. Wall thickening alone is nonspecific.

Question 42Thoracic Imaging

A patient with a history of asbestos exposure has a chest radiograph showing bilateral lower zone reticular opacities and pleural plaques. Which additional finding would most suggest malignant transformation?

  1. Progressive pleural thickening with nodularity Correct answer.
  2. Bilateral hilar enlargement with eggshell calcification
  3. Apical pleural thickening
  4. Stable calcified diaphragmatic plaques

Explanation

Asbestos-related pleural disease can undergo malignant transformation into mesothelioma, suggested by progressive, nodular pleural thickening or a pleural mass. Stable calcified plaques are a benign marker of exposure.

Question 43Thoracic Imaging

The most characteristic chest radiograph appearance of sarcoidosis is:

  1. Lower-zone honeycombing
  2. Unilateral apical cavitation
  3. Bilateral symmetrical hilar lymphadenopathy with or without paratracheal involvement Correct answer.
  4. Unilateral hilar enlargement with pleural effusion

Explanation

Sarcoidosis classically produces bilateral, roughly symmetrical hilar and right paratracheal lymphadenopathy, often described as the Garland triad. Parenchymal disease may follow.

Question 44Thoracic Imaging

A chest radiograph in a patient with mitral stenosis shows prominent upper lobe pulmonary veins. This finding is best explained by:

  1. Reduced pulmonary blood flow from right heart failure
  2. Air trapping from small airways disease
  3. Increased left atrial pressure with cephalization of pulmonary blood flow Correct answer.
  4. Pulmonary arterial hypertension from chronic embolism

Explanation

Elevated left atrial pressure causes redistribution of pulmonary blood flow to the upper lobes, known as cephalization. This is an early sign of pulmonary venous hypertension.

Question 45Thoracic Imaging

On a chest radiograph, which feature most favors a cavitating lung lesion being a primary lung carcinoma rather than a tuberculous cavity?

  1. Thin smooth wall less than 4 mm
  2. Cavitation with surrounding consolidation in the apex
  3. Thick, irregular wall with an eccentric cavity in an upper lobe mass Correct answer.
  4. Multiple small cavities in the lower lobes

Explanation

Malignant cavities typically have a thick, irregular wall and arise within a mass, often with an eccentric cavity. Thin-walled cavities favor benign processes such as tuberculosis, abscess, or bullae.

Question 46Thoracic Imaging

Which CT sign is most useful for distinguishing a benign simple cyst from a lung abscess?

  1. Smooth thin wall with water attenuation and no surrounding consolidation Correct answer.
  2. Size greater than 3 cm
  3. Presence of an air-fluid level
  4. Location in the upper lobe

Explanation

A simple cyst has a thin, smooth wall with water attenuation and no surrounding consolidation. An abscess shows a thicker enhancing wall with surrounding consolidation and often an air-fluid level.

Question 47Thoracic Imaging

Which radiographic finding is most consistent with tension pneumothorax?

  1. Basal pleural thickening
  2. Ipsilateral mediastinal shift with elevation of the hemidiaphragm
  3. Contralateral mediastinal shift with depression of the ipsilateral hemidiaphragm Correct answer.
  4. Bilateral hilar enlargement

Explanation

Tension pneumothorax produces progressively increasing intrapleural pressure, shifting the mediastinum to the contralateral side and depressing the ipsilateral hemidiaphragm. This is a clinical diagnosis requiring urgent decompression.

Question 48Thoracic Imaging

A patient with fever and cough has a chest radiograph showing a retrocardiac opacity with an air bronchogram; on lateral view the opacity lies posterior to the oblique fissure. Which lobe is involved?

  1. Left lower lobe Correct answer.
  2. Left upper lobe
  3. Lingula
  4. Right middle lobe

Explanation

The left lower lobe lies posterior to the oblique fissure and produces retrocardiac opacity on the frontal view. Air bronchograms confirm airspace consolidation.

Question 49Thoracic Imaging

Which chest radiograph finding is most typical of pulmonary alveolar proteinosis?

  1. Apical cavitation with volume loss
  2. Bilateral symmetrical perihilar ground-glass opacity with a 'bat-wing' distribution Correct answer.
  3. Unilateral pleural effusion with nodular thickening
  4. Bilateral hilar calcification

Explanation

Pulmonary alveolar proteinosis classically produces bilateral symmetrical perihilar airspace opacity with a bat-wing or butterfly distribution. The pattern reflects alveolar filling rather than interstitial disease.

Question 50Thoracic Imaging

A patient with a known malignancy develops multiple bilateral pulmonary nodules of varying sizes with a 'cannonball' appearance. This pattern most likely represents:

  1. Sarcoidosis
  2. Hematogenous metastases Correct answer.
  3. Lymphangitic carcinomatosis
  4. Miliary tuberculosis

Explanation

Multiple bilateral nodules of varying sizes, including larger 'cannonball' lesions, are typical of hematogenous metastases. Lymphangitic spread produces linear and reticular opacities rather than discrete nodules.