Neuroradiology Practice Questions

Q: A patient presents with proptosis and abducent nerve palsy. A dark homogenous mass is seen on T2W MRI, which shows intense enhancement with contrast. What is the diagnosis?

Cavernous hemangioma. **Explanation:** The clinical presentation of proptosis and abducent nerve (CN VI) palsy, combined with specific MRI findings, points directly to an **Orbital Cavernous Hemangioma**. 1. **Why Cavernous Hemangioma is correct:** * **Clinical:** It is the most common benign orbital tumor in adults, typically causing slowly progressive proptosis. * **MRI Characteristics:** On T2-weighted imaging, these lesions characteristically appear as **well-circumscribed, dark (hypointense) to intermediate** masses relative to the bright orbital fat, but they are often described as **homogeneously hyperintense** compared to muscle. * **Contrast Enhancement:** They show **intense, progressive enhancement** (often starting patchy and becoming homogenous) due to the slow-flowing blood within the vascular spaces. 2. **Why other options are incorrect:** * **Meningioma:** Specifically Optic Nerve Sheath Meningiomas show the "Tram-track sign" on contrast CT/MRI. While they enhance, they are usually tubular and follow the nerve's course rather than appearing as a discrete mass. * **Astrocytoma/Glioma:** Optic nerve gliomas typically cause fusiform enlargement of the optic nerve and are associated with Neurofibromatosis Type 1 (NF1). They do not typically present as a "dark homogenous mass" on T2 in this specific clinical context. **High-Yield Pearls for NEET-PG:** * **Most common benign orbital tumor in adults:** Cavernous Hemangioma. * **Most common benign orbital tumor in children:** Capillary Hemangioma (often regresses spontaneously). * **T2 MRI Rule:** Most vascular tumors are bright on T2; however, the "dark" description in the question refers to its appearance relative to the surrounding high-signal orbital fat. * **Key Sign:** "Filling-in" phenomenon (progressive enhancement on delayed scans) is a hallmark of cavernous lesions.

Q: Which of the following is NOT a typical finding in meningioma?

Erosion. **Explanation:** Meningiomas are the most common benign intracranial tumors, arising from the arachnoid cap cells. The key to answering this question lies in understanding the tumor's effect on the adjacent bone. **Why "Erosion" is the correct answer:** Meningiomas are typically slow-growing, extra-axial tumors. Rather than destroying or eroding the bone (which is more characteristic of malignant tumors or metastases), they tend to provoke a reactive bone response. While pressure atrophy can occur in rare cases, **erosion** is not a typical or classic feature of meningioma. **Analysis of incorrect options:** * **Vascular markings:** Meningiomas are highly vascular tumors, often supplied by the middle meningeal artery. On a skull X-ray, this manifests as enlargement of the grooves for the meningeal vessels (vascular markings) around the falx or convexity. * **Calcification:** This is a very common finding, seen in approximately 20–25% of cases. Histologically, this corresponds to the presence of **psammoma bodies**. * **Osteosclerosis (Hyperostosis):** This is a hallmark radiological sign. The tumor cells invade the Haversian canals of the adjacent bone, stimulating new bone formation. This results in reactive thickening and increased density of the bone overlying the tumor. **High-Yield Pearls for NEET-PG:** * **Dural Tail Sign:** A classic MRI finding (contrast enhancement of the thickened dura adjacent to the tumor). * **Sunburst/Spoke-wheel Appearance:** Seen on angiography due to the radial arrangement of feeding vessels. * **Most common location:** Parasagittal/Falcine. * **Association:** Neurofibromatosis Type 2 (NF2) – often presents with multiple meningiomas.

Q: A 55-year-old male presents with sudden onset of thunderclap headache followed by loss of consciousness for 4 hours. What is the initial investigation of choice?

Non-contrast CT followed by angiogram. **Explanation:** The clinical presentation of a **"thunderclap headache"** (sudden, maximal intensity "worst headache of life") followed by loss of consciousness is the classic hallmark of a **Subarachnoid Hemorrhage (SAH)**, most commonly due to a ruptured berry aneurysm. **1. Why Option A is Correct:** * **Non-Contrast CT (NCCT) Head:** This is the **initial investigation of choice** because it is highly sensitive (up to 98% in the first 24 hours) for detecting acute blood in the subarachnoid space. Blood appears hyperdense (white) on NCCT. * **Angiogram:** Once SAH is confirmed, the next step is to identify the source of bleeding (e.g., an aneurysm or AVM). **Digital Subtraction Angiography (DSA)** remains the gold standard, though CT Angiography (CTA) is often used first in clinical practice to plan surgical or endovascular intervention. **2. Why Other Options are Incorrect:** * **B. PET Scan:** Used for metabolic activity (oncology/dementia), not for acute vascular emergencies. * **C. MRI Angiogram:** While sensitive, MRI is time-consuming, less available in emergencies, and less sensitive than CT for acute hyperacute blood. * **D. Contrast-Enhanced CT (CECT):** Iodine contrast can mask the appearance of acute blood, as both appear white (hyperdense). NCCT is always preferred for suspected hemorrhage. **Clinical Pearls for NEET-PG:** * **Gold Standard for SAH diagnosis:** NCCT Head. * **If NCCT is negative but clinical suspicion is high:** Perform a **Lumbar Puncture** to look for xanthochromia (yellowish CSF due to bilirubin). * **Gold Standard for identifying the cause (Aneurysm):** Digital Subtraction Angiography (DSA). * **Most common site of Berry Aneurysm:** Anterior Communicating Artery (A-com).

Q: What is the best test to determine the etiology of subarachnoid hemorrhage (SAH)?

Intra-arterial digital subtraction angiography. **Explanation:** The gold standard for determining the **etiology** of a subarachnoid hemorrhage (SAH) is **Intra-arterial Digital Subtraction Angiography (DSA)**. While other modalities can detect the presence of blood, DSA provides the highest spatial resolution to identify the underlying vascular cause, such as a ruptured berry aneurysm (85% of cases), arteriovenous malformations (AVMs), or dural arteriovenous fistulas. It allows for 360-degree visualization and remains the definitive "map" for planning neurosurgical clipping or endovascular coiling. **Analysis of Options:** * **Unenhanced (Non-contrast) CT scan:** This is the **investigation of choice for the initial diagnosis** (detecting blood) of SAH, with nearly 100% sensitivity in the first 6–12 hours. However, it cannot reliably identify the specific etiology/source of the bleed. * **Enhanced CT scan:** Contrast-enhanced CT is generally avoided in the acute phase of SAH as the hyperdense contrast can be mistaken for or obscure the hyperdense acute blood. * **MRI:** While sensitive for subacute or chronic SAH (using FLAIR or SWI sequences), it is not the primary tool for determining etiology in the acute setting due to time constraints and lower resolution for small aneurysms compared to DSA. **Clinical Pearls for NEET-PG:** * **Initial Investigation of Choice:** Non-contrast CT (NCCT) Head. * **Gold Standard for Etiology:** Digital Subtraction Angiography (DSA). * **Most sensitive test if CT is negative:** Lumbar Puncture (looking for xanthochromia). * **Commonest site of Berry Aneurysm:** Anterior Communicating Artery (A-com). * **CT Angiography (CTA):** Often used as the first-line non-invasive vascular study, but DSA remains the definitive "best test."

Q: All of the following calcify except –

Medulloblastoma. **Explanation:** The correct answer is **Medulloblastoma**. In pediatric neuroradiology, intracranial calcification is a key differentiating feature. While medulloblastomas are highly cellular, "small round blue cell" tumors of the posterior fossa, they **rarely calcify (<10% of cases)**. They typically present as a midline mass arising from the roof of the 4th ventricle with homogenous enhancement. **Analysis of Options:** * **Sturge-Weber Syndrome:** Characterized by classic **"tram-track" calcifications**. These are cortical/subcortical gyriform calcifications caused by chronic ischemia underlying a leptomeningeal angioma. * **Meningioma:** These are the most common extra-axial tumors in adults. Calcification is a hallmark feature (seen in ~20-25% of cases), often appearing as **psammomatous bodies** (sand-like calcifications) on histopathology. * **Ependymoma:** In contrast to medulloblastoma, ependymomas (which arise from the floor of the 4th ventricle) calcify very frequently (**~50% of cases**). They are often described as "plastic" tumors because they squeeze through the foramina of Luschka and Magendie. **High-Yield Clinical Pearls for NEET-PG:** 1. **Rule of Thumb for Posterior Fossa:** If a midline pediatric tumor calcifies, think **Ependymoma**; if it doesn't, think **Medulloblastoma**. 2. **Most common calcified brain tumor:** Craniopharyngioma (90% calcify in children). 3. **Most common calcified intra-axial tumor in adults:** Oligodendroglioma ("Chicken-wire" vascularity and 70-90% calcification). 4. **Physiological Calcifications:** Pineal gland (>10 years), Habenular commissure, and Choroid plexus.

Q: A comatose road traffic accident patient presents with a unilaterally dilated pupil. NCCT of the head reveals a peripheral lesion with a concavo-convex border. What is the probable diagnosis?

Subdural hematoma. ### Explanation The correct diagnosis is **Subdural Hematoma (SDH)**. **1. Why Subdural Hematoma is correct:** The key radiological descriptor is the **"concavo-convex"** (crescent-shaped) border. An SDH occurs due to the tearing of **bridging cortical veins** as they cross the subdural space to drain into the dural sinuses. Because the subdural space is a potential space not limited by cranial sutures, the blood spreads extensively along the inner table of the skull, following the curve of the brain, resulting in a crescentic shape. The unilaterally dilated pupil indicates **uncal herniation** (compression of the ipsilateral CN III), a common complication of the mass effect caused by a large SDH. **2. Why other options are incorrect:** * **Epidural Hematoma (EDH):** Characterized by a **biconvex or lenticular** (lemon-shaped) appearance. It is caused by arterial bleeding (usually the Middle Meningeal Artery) and is limited by cranial sutures where the dura is firmly attached. * **Subarachnoid Hemorrhage (SAH):** Typically appears as hyperdensity within the **sulci, fissures, and basal cisterns** (often described as a "star-shaped" density in the circle of Willis), rather than a peripheral collection. * **Intraparenchymal bleeding:** This occurs **within the brain tissue** itself (white or gray matter) and does not follow the peripheral borders of the skull. **3. NEET-PG High-Yield Pearls:** * **SDH Shape:** Crescentic / Concavo-convex (Crosses suture lines). * **EDH Shape:** Lenticular / Biconvex (Does **not** cross suture lines). * **Source of Bleed:** SDH = Bridging Veins; EDH = Middle Meningeal Artery. * **Chronic SDH:** Appears **hypodense** (dark) on NCCT, whereas acute SDH is **hyperdense** (bright). * **Clinical Sign:** A unilaterally dilated, non-reactive pupil in head trauma is a neurosurgical emergency indicating impending transtentorial herniation.

Q: On non-contrast computed tomography (NCCT) of the head, what is the typical appearance of an extradural hemorrhage?

Hyperdense biconvex. ### Explanation **Correct Option: A. Hyperdense biconvex** **Why it is correct:** An **Extradural Hemorrhage (EDH)**, also known as an epidural hematoma, typically results from the rupture of the **middle meningeal artery** (often due to a temporal bone fracture). On NCCT, acute blood appears **hyperdense** (bright white) because of the high hemoglobin concentration. The blood collects between the inner table of the skull and the tough dural layer. Because the dura is firmly attached to the cranial sutures, the expanding hematoma is confined, forcing it to bulge inward into a characteristic **biconvex (lentiform or lens-shaped)** shape. Crucially, EDH **does not cross suture lines** but can cross the midline (dural folds). **Why other options are incorrect:** * **B & D (Hypodense):** Acute blood is hyperdense. Hypodensity in a hematoma usually indicates an older, chronic stage (liquefaction) or the "swirl sign" (active hyperacute bleeding), which is not the "typical" acute presentation. * **C (Biconcave):** A biconcave or **crescentic** shape is the hallmark of a **Subdural Hemorrhage (SDH)**. SDH occurs due to the tearing of bridging veins; since the subdural space is a potential space not limited by sutures, the blood spreads thinly along the brain's convexity. **High-Yield Clinical Pearls for NEET-PG:** * **Clinical Presentation:** Classically associated with a **"Lucid Interval"** (initial loss of consciousness → temporary recovery → rapid deterioration). * **Source of Bleed:** 90% are arterial (Middle Meningeal Artery); 10% are venous (Dural venous sinuses). * **Management:** Large or symptomatic EDHs are surgical emergencies requiring urgent **craniotomy and evacuation**. * **Imaging Rule:** EDH = Lens-shaped/Biconvex; SDH = Banana-shaped/Crescentic.

Q: In subclavian steal syndrome, there is reversal of blood flow in which artery?

Ipsilateral vertebral artery. **Explanation:** **Subclavian Steal Syndrome (SSS)** occurs due to a high-grade stenosis or total occlusion of the **subclavian artery** proximal to the origin of the **vertebral artery**. 1. **Why Option A is correct:** Because of the proximal obstruction, the pressure in the distal subclavian artery drops below the pressure in the cerebral circulation. To compensate and supply blood to the affected arm, blood is "stolen" from the brain. It flows up the contralateral vertebral artery, across the basilar artery, and then travels **retrograde (downward)** through the **ipsilateral vertebral artery** to reach the subclavian artery distal to the blockage. Thus, the reversal of flow occurs in the vertebral artery on the same side as the lesion. 2. **Why other options are incorrect:** * **Option B:** The contralateral vertebral artery maintains normal antegrade flow to provide the blood that is eventually diverted. * **Options C & D:** While the subclavian artery is the site of the *pathology* (stenosis), the flow within it remains antegrade (though diminished). The "steal" phenomenon specifically refers to the reversal of flow in the tributary vessel (the vertebral artery). **Clinical Pearls for NEET-PG:** * **Clinical Presentation:** Patients often present with upper limb ischemia (claudication, coldness) and vertebrobasilar insufficiency (vertigo, syncope, diplopia), especially when exercising the affected arm. * **Physical Exam:** A significant difference in blood pressure (usually **>20 mmHg**) between the two arms is a classic finding. * **Diagnosis:** Color Doppler Ultrasound is the initial investigation of choice (shows "systolic deceleration" or "retrograde flow"). Digital Subtraction Angiography (DSA) remains the gold standard. * **Side Predilection:** The **left side** is more commonly affected than the right.

Q: Suprasellar calcification is characteristic of which of the following conditions?

Craniopharyngioma. **Explanation:** **Craniopharyngioma** is the most common suprasellar tumor in children and is the classic answer for suprasellar calcification. These tumors arise from remnants of **Rathke’s pouch**. The characteristic "90% Rule" applies here: approximately 90% of pediatric craniopharyngiomas (adamantinomatous type) show calcification on CT, along with cystic components containing "motor-oil" fluid. **Analysis of Incorrect Options:** * **Option A (Toxoplasmosis, CMV, Cysticercosis):** These typically present with **intraparenchymal** calcifications rather than suprasellar ones. Toxoplasmosis causes scattered/diffuse calcifications, CMV causes **periventricular** calcifications, and Cysticercosis (NCC) shows "starry sky" appearances in the parenchyma. * **Option B (Medulloblastoma):** This is an infratentorial tumor arising from the **roof of the 4th ventricle** in the posterior fossa. While it may show faint calcification (10-20%), its location is not suprasellar. * **Option D (Meningioma):** While meningiomas can calcify (psammoma bodies) and occur in the suprasellar region (suprasellar notch), they are primarily tumors of adults and appear as intensely enhancing, solid extra-axial masses with a "dural tail" rather than the cystic-calcified appearance of craniopharyngiomas. **High-Yield Clinical Pearls for NEET-PG:** * **Craniopharyngioma Bimodal Age Distribution:** 5–14 years and 50–75 years. * **Visual Deficit:** Often presents with **bitemporal hemianopia** due to compression of the optic chiasm. * **MRI Appearance:** T1-hyperintense cysts (due to high protein/cholesterol) and heterogeneous enhancement. * **Differential for Suprasellar Mass (SATCHMO):** **S**ella turcica (adenoma), **A**neurysm, **T**eratoma/Craniopharyngioma, **C**hiasmatic glioma, **H**ypothalamic hamartoma, **M**eningioma, **O**ptic nerve glioma.

Question 1

A patient presents with proptosis and abducent nerve palsy. A dark homogenous mass is seen on T2W MRI, which shows intense enhancement with contrast. What is the diagnosis?

Accepted Answer

Cavernous hemangioma

Answer

Meningioma

Answer

Astrocytoma

Answer

Glioma

Question 2

Which of the following is NOT a typical finding in meningioma?

Accepted Answer

Erosion

Answer

Vascular markings around falx

Answer

Calcification

Answer

Osteosclerosis

Question 3

A 55-year-old male presents with sudden onset of thunderclap headache followed by loss of consciousness for 4 hours. What is the initial investigation of choice?

Accepted Answer

Non-contrast CT followed by angiogram

Answer

PET scan

Answer

MRI angiogram

Answer

Contrast-enhanced CT

Question 4

What is the best test to determine the etiology of subarachnoid hemorrhage (SAH)?

Accepted Answer

Intra-arterial digital subtraction angiography

Answer

Enhanced CT scan

Answer

Unenhanced CT scan

Answer

MRI

Question 5

All of the following calcify except –

Accepted Answer

Medulloblastoma

Answer

Sturge weber syndrome

Answer

Meningioma

Answer

Ependymoma

Question 6

Agenesis of cerebellar vermis, large posterior fossa with megacisterna magna is a feature of which condition?

Accepted Answer

Dandy Walker malformation

Answer

Von Hippel-Lindau syndrome

Answer

Sturge Weber syndrome

Answer

Chiari malformation

Question 7

A comatose road traffic accident patient presents with a unilaterally dilated pupil. NCCT of the head reveals a peripheral lesion with a concavo-convex border. What is the probable diagnosis?

Accepted Answer

Subdural hematoma

Answer

Epidural hematoma

Answer

Subarachnoid hemorrhage

Answer

Intraparenchymal bleeding

Question 8

On non-contrast computed tomography (NCCT) of the head, what is the typical appearance of an extradural hemorrhage?

Accepted Answer

Hyperdense biconvex

Answer

Hypodense biconcave

Answer

Hyperdense biconcave

Answer

Hypodense biconvex

Question 9

In subclavian steal syndrome, there is reversal of blood flow in which artery?

Accepted Answer

Ipsilateral vertebral artery

Answer

Contralateral vertebral artery

Answer

Ipsilateral subclavian artery

Answer

Contralateral subclavian artery

Question 10

Suprasellar calcification is characteristic of which of the following conditions?

Accepted Answer

Craniopharyngioma

Answer

Toxoplasmosis, Cytomegalovirus (CMV), Cysticercosis

Answer

Medulloblastoma

Answer

Meningioma

Neuroradiology — MCQs

Neuroradiology — MCQs

On this page

Practice by Chapter

Want unlimited practice?