Neuroradiology Practice Questions

Q: A cystic lesion with calcification is noted in the suprasellar region. What is the most likely diagnosis?

Craniopharyngioma. **Explanation:** The correct answer is **Craniopharyngioma**. This is a benign, slow-growing tumor derived from the remnants of **Rathke’s pouch**. The classic imaging triad for a craniopharyngioma (specifically the adamantinomatous type) is a **suprasellar mass** that is **cystic**, contains **calcification**, and shows **solid component enhancement**. In the pediatric population, calcification is seen in approximately 90% of cases, making it a hallmark feature for NEET-PG questions. **Why other options are incorrect:** * **Meningioma:** While common in the suprasellar region (tuberculum sellae), they are typically **solid, intensely enhancing**, and dural-based. While they can show psammomatous calcification, they are rarely cystic. * **Pituitary Adenoma:** These are the most common sellar masses. However, they are usually **isointense** to gray matter on MRI and **rarely calcify** (less than 1–2%). They typically cause expansion of the sella turcica. * **Oligodendroglioma:** Although known for "chunky" calcifications, these are **intra-axial** tumors usually located in the cortical-subcortical white matter of the cerebral hemispheres (frontal lobe), not the suprasellar cistern. **High-Yield Clinical Pearls for NEET-PG:** * **Bimodal Distribution:** Peaks at 5–14 years and 50–75 years. * **Types:** *Adamantinomatous* (Children, "machinery oil" fluid, calcified) vs. *Papillary* (Adults, solid, rarely calcified). * **Clinical Presentation:** Bitemporal hemianopia (due to optic chiasm compression) and endocrine dysfunction (growth retardation or diabetes insipidus). * **Radiology Sign:** "Machinery oil" appearance of cyst fluid on gross pathology.

Q: Based upon this coronal CT view of the face in a 25-year-old man with eye pain, what is the MOST likely diagnosis?

Blowout fracture. ***Blowout fracture*** - Classic coronal CT findings include the **teardrop sign** (herniated orbital fat into maxillary sinus) and **orbital floor disruption** with associated eye pain. - Typically occurs after **blunt trauma** to the orbit, causing increased intraorbital pressure and fracture of the thin orbital floor. *Maxillary sinusitis* - Would show **mucosal thickening** or **fluid levels** within the maxillary sinus, not orbital fat herniation. - Presents with **facial pain** and **nasal congestion** rather than isolated eye pain from orbital injury. *Neoplasm of the maxillary sinus* - Appears as a **soft tissue mass** with possible **bone destruction** and irregular margins on CT. - Typically presents with **chronic symptoms** like nasal obstruction and epistaxis, not acute eye pain in a young patient. *Orbital lipoma* - Shows as a **well-defined fatty mass** within the orbit with **homogeneous fat density** on CT. - Does not cause **orbital floor fracture** or herniation into the maxillary sinus, and is usually asymptomatic.

Q: Soap bubble calcification is a feature of which condition?

Paragonimus cyst. **Explanation:** **Paragonimiasis (Paragonimus westermani)** is a parasitic infection caused by lung flukes, which can occasionally involve the Central Nervous System (CNS). The characteristic imaging finding in cerebral paragonimiasis is the **"Soap Bubble" appearance**. This occurs due to multiple, clustered, ring-enhancing lesions or granulomas that undergo peripheral calcification. These aggregated calcified cysts resemble a cluster of soap bubbles on a CT scan or X-ray, making it a pathognomonic sign for this condition. **Analysis of Incorrect Options:** * **Toxoplasmosis:** Typically presents with multiple ring-enhancing lesions (often in the basal ganglia) and may show calcification in congenital cases or post-treatment. However, the calcifications are usually **nodular or scattered**, not "soap bubble" in appearance. * **Corpus Callosal Lipoma:** This is a midline fat-containing lesion. While it can show calcification, it typically presents with a characteristic **"Bracket sign"** (curvilinear calcification along the periphery of the lipoma), not soap bubble clusters. **High-Yield Clinical Pearls for NEET-PG:** * **Soap Bubble Appearance (Radiology):** 1. **Paragonimiasis:** Intracranial calcified cysts. 2. **Giant Cell Tumor (GCT) of Bone:** Eccentric, expansile lytic lesion in the epiphysis. 3. **Ameloblastoma:** Multilocular radiolucency in the mandible. 4. **Chordoma:** Destructive bone lesion (often sacrum/clivus). * **Cerebral Paragonimiasis** is most common in East Asia and should be suspected in patients with eosinophilia, seizures, and clustered intracranial calcifications.

Q: A hypertensive patient was admitted with right hemiplegia. A plain CT scan shows what?

Hemorrhage in the left thalamus and internal capsule. ***Hemorrhage in the left thalamus and internal capsule*** - **Hypertensive hemorrhages** commonly occur in the **thalamus** and **internal capsule**, appearing as **hyperdense** (bright white) lesions on plain CT scan. - Left-sided lesions in these structures cause **contralateral hemiplegia** (right-sided weakness) due to disruption of **motor pathways**. - It is the **hyperdense left deep hemorrhage extending through the thalamic/internal-capsular region** that establishes option A over the ischemic alternatives, as acute ischemic infarcts appear hypodense or are invisible on early CT, not hyperdense. *Hemorrhage in the left frontal lobe* - Frontal lobe hemorrhage would typically cause **behavioral changes** and **personality disorders**, though cortical lesions involving the **primary motor cortex** can produce **substantial contralateral hemiplegia** when motor pathways are involved. - However, the CT here demonstrates a **hyperdense deep lesion** in the thalamus and internal capsule, not a frontal cortical hemorrhage. *Ischemic infarct in the internal capsule* - **Acute ischemic infarcts** appear **hypodense** (dark) on CT, but are often **not visible** in the first 24 hours. - Plain CT has **poor sensitivity** for acute ischemic strokes, especially in small vessel territories like the internal capsule. *Ischemic infarct in the left parietal lobe* - Parietal lobe infarcts primarily cause **sensory deficits** and **neglect syndromes** rather than motor hemiplegia. - **Acute ischemic changes** are typically **not visible** on plain CT in the first few hours after symptom onset.

Q: Basal exudates, infarcts, and hydrocephalus are findings observed in brain imaging studies. What is the most likely diagnosis?

Tubercular meningitis. ### Explanation The classic triad of **basal exudates, infarcts, and hydrocephalus** on neuroimaging is highly pathognomonic for **Tubercular Meningitis (TBM)**. 1. **Why Tubercular Meningitis is correct:** * **Basal Exudates:** *M. tuberculosis* has a predilection for the base of the brain (interpeduncular cistern, ambient cisterns). These thick, gelatinous exudates appear as intense enhancement on contrast-enhanced CT or MRI. * **Infarcts:** The exudates surround the Circle of Willis, leading to **vasculitis** of the small perforating arteries (e.g., lenticulostriate arteries), most commonly resulting in infarcts in the basal ganglia and internal capsule (the "Medial Striate Syndrome"). * **Hydrocephalus:** This is usually **communicating** type, caused by the exudates obstructing the basal cisterns and interfering with CSF resorption at the arachnoid villi. 2. **Why the other options are incorrect:** * **Viral Meningitis:** Typically presents with normal imaging or mild meningeal enhancement; it does not cause thick basal exudates or infarcts. * **Herpes Encephalitis:** Characteristically involves the **temporal lobes** and limbic system (insular cortex, cingulate gyrus). It presents with edema and hemorrhage rather than basal exudates. * **Cerebral Malaria:** Imaging often shows diffuse cerebral edema or small petechial hemorrhages, but not the specific triad of basal exudates and hydrocephalus. ### High-Yield Pearls for NEET-PG: * **Most common site for TBM infarcts:** Basal ganglia (due to involvement of the Medial Striate arteries). * **Tuberculoma:** The most common "ring-enhancing lesion" in India; shows a "target sign" (central calcification) on CT. * **Gold Standard Diagnosis:** CSF GeneXpert (CBNAAT) or culture, though imaging is often the first clue. * **Hydrocephalus in TBM:** Usually communicating; however, it can be obstructive if a tuberculoma blocks the Aqueduct of Sylvius.

Q: Which imaging modality can help to study CSF dynamics?

MR CSF flowmetry. **Explanation:** **MR CSF Flowmetry** (Phase-Contrast MRI) is the gold standard for non-invasive evaluation of cerebrospinal fluid (CSF) dynamics. It utilizes the phase shifts of protons moving within a magnetic field to quantify the velocity and direction of CSF flow throughout the cardiac cycle. This is clinically vital for diagnosing **Normal Pressure Hydrocephalus (NPH)**, where a "flow void" or hyperdynamic flow is often seen at the Aqueduct of Sylvius, and for assessing conditions like Chiari malformations or syringomyelia. **Why other options are incorrect:** * **Transcranial Ultrasound Doppler:** This modality measures the velocity of **blood flow** within the major intracranial arteries (e.g., Middle Cerebral Artery) to detect vasospasm or stenosis; it does not visualize CSF movement. * **CT Ventriculography:** While it involves injecting contrast into the ventricles to check for obstructions, it is an invasive procedure and provides anatomical detail rather than functional "dynamics" or flow quantification. * **PET Scan:** This is a functional imaging tool used to study **cerebral glucose metabolism** (using FDG) or neurotransmitter activity, primarily in oncology and dementia workups, not fluid kinetics. **High-Yield Clinical Pearls for NEET-PG:** * **NPH Triad (Hakim’s Triad):** Urinary incontinence, Gait ataxia, and Dementia ("Wet, Wobbly, and Wacky"). * **MRI Sign:** Look for the **"Flow Void"** sign in the Aqueduct of Sylvius on T2-weighted images, indicating turbulent/hyperdynamic CSF flow. * **Radionuclide Cisternography:** Another (though more invasive/older) method to study CSF flow, often used to confirm NPH or detect CSF leaks.

Q: A dumbbell tumor is a characteristic feature of which of the following neoplasms?

Neurofibroma. ### Explanation **Correct Answer: B. Neurofibroma** A **dumbbell (or hourglass) tumor** is a classic radiological and pathological description for a spinal nerve sheath tumor, most commonly a **Neurofibroma** or a **Schwannoma**. The "dumbbell" shape occurs because the tumor originates from a spinal nerve root within the spinal canal. As it grows, it extends through the narrow **intervertebral foramen** into the paravertebral space. The constriction caused by the bony foramen creates a "waist," resulting in a bulbous mass both inside and outside the spinal canal. On imaging (MRI/CT), this leads to the characteristic **widening of the intervertebral foramen** and erosion of adjacent pedicles. **Analysis of Incorrect Options:** * **A. Meningioma:** While these are common intradural-extramedullary tumors, they are typically broad-based, dural-attached, and globular. They rarely exit the foramen to form a dumbbell shape. * **C. Ependymoma:** These are the most common **intramedullary** (inside the cord) tumors in adults. They cause cord expansion rather than foraminal extension. * **D. Thymoma:** These are anterior mediastinal tumors. While they can be associated with Myasthenia Gravis, they do not exhibit a dumbbell morphology related to the spinal column. **NEET-PG High-Yield Pearls:** * **Most common cause of dumbbell tumor:** Schwannoma (more frequent than Neurofibroma). * **Imaging Modality of Choice:** MRI with contrast (shows intense enhancement). * **Neurofibromatosis Type 1 (NF1):** Strongly associated with multiple plexiform neurofibromas. * **Differential Diagnosis:** If a dumbbell-shaped mass is seen in a **pediatric** patient in the posterior mediastinum, consider **Neuroblastoma**.

Question 1

A cystic lesion with calcification is noted in the suprasellar region. What is the most likely diagnosis?

Accepted Answer

Craniopharyngioma

Answer

Meningioma

Answer

Pituitary adenoma

Answer

Oligodendroglioma

Question 2

Based upon this coronal CT view of the face in a 25-year-old man with eye pain, what is the MOST likely diagnosis?

Accepted Answer

Blowout fracture

Answer

Maxillary sinusitis

Answer

Neoplasm of the maxillary sinus

Answer

Orbital lipoma

Question 3

Soap bubble calcification is a feature of which condition?

Accepted Answer

Paragonimus cyst

Answer

Toxoplasmosis

Answer

Corpus callosal Lipoma

Answer

All of the above

Question 4

A hypertensive patient was admitted with right hemiplegia. A plain CT scan shows what?

Accepted Answer

Hemorrhage in the left thalamus and internal capsule

Answer

Hemorrhage in the left frontal lobe

Answer

Ischemic infarct in the left parietal lobe

Answer

Ischemic infarct in the internal capsule

Question 5

Basal exudates, infarcts, and hydrocephalus are findings observed in brain imaging studies. What is the most likely diagnosis?

Accepted Answer

Tubercular meningitis

Answer

Viral meningitis

Answer

Herpes encephalitis

Answer

Cerebral Malaria

Question 6

What is the most common cause of intracranial calcification?

Accepted Answer

Pineal calcification

Answer

Intracranial aneurysm

Answer

Meningioma

Answer

Tuberculoma

Question 7

An 80-year-old male presents with a 5-day history of high-grade fever, cognitive decline, and behavioral disturbances. There is no history of travel or contact with TB patients. NCCT head revealed a hypodense lesion with edema in the left frontal lobe. MRI was performed and demonstrated a ring-enhancing lesion with central DWI hyperintensity and corresponding low ADC signal (restricted diffusion), confirming viscous pus within the cavity. What is the most likely diagnosis?

Accepted Answer

Pyogenic abscess

Answer

Glioblastoma multiforme

Answer

Tubercular abscess

Answer

Hydatid cyst

Question 8

Compression of the carotid artery by a Glomus jugulare tumor is diagnosed by which imaging modality?

Accepted Answer

MR angiography

Answer

CECT

Answer

X-ray

Answer

Jugular venography

Question 9

Which imaging modality can help to study CSF dynamics?

Accepted Answer

MR CSF flowmetry

Answer

Transcranial ultrasound Doppler

Answer

CT ventriculography

Answer

PET scan

Question 10

A dumbbell tumor is a characteristic feature of which of the following neoplasms?

Accepted Answer

Neurofibroma

Answer

Meningioma

Answer

Ependymoma

Answer

Thymoma

Neuroradiology — MCQs

Neuroradiology — MCQs

On this page

Practice by Chapter

Want unlimited practice?