Test: Neuroradiology - 3 - NEET PG MCQ

The CT scan indicates a biconvex hyperdense lesion that is pushing the grey-white matter boundary. This finding suggests a condition where blood accumulates between the skull and the outer layer of the brain.

• Extradural hematoma occurs when blood collects between the skull and the dura mater, leading to a biconvex shape on the CT scan.
• This type of hematoma is typically caused by trauma, often following a head injury.
• In contrast, a subdural hematoma would appear as a crescent-shaped lesion and typically occurs due to tearing of the bridging veins.
• Diffuse axonal injury and hemorrhagic contusion would present differently on imaging and are not associated with a biconvex shape.

Therefore, the most likely diagnosis is an extradural hematoma.

The most effective initial test for a patient suspected of having a subarachnoid hemorrhage is a:

• Non-contrast computed tomography (CT scan). This imaging technique is quick and can effectively detect bleeding in the brain.
• Other tests, such as CSF examination, magnetic resonance imaging (MRI), and contrast-enhanced CT, are not typically used as first-line investigations.

In summary, a non-contrast CT scan is the best starting point for diagnosis.

The best way to diagnose acoustic neuroma is through:

• Gadolinium enhanced MRI: This imaging technique provides detailed pictures of the brain and can effectively show the presence of tumours.
• CT scan: This is useful but may not detect smaller tumours as clearly as an MRI.
• Audiometric analysis: This tests hearing ability but does not diagnose the condition directly.
• PET scan: While it provides some information about brain activity, it is not the first choice for diagnosing acoustic neuroma.

Therefore, the most reliable method for diagnosis is Gadolinium enhanced MRI.

The best method to evaluate a posterior fossa tumour is through MRI. This imaging technique provides detailed pictures of the brain and surrounding areas, helping to identify the size, location, and characteristics of the tumour.

Here are some reasons why MRI is preferred:

• High resolution: MRI offers clearer images compared to other techniques.
• Non-invasive: It does not involve any surgical procedures.
• No radiation: Unlike CT scans, MRI does not use harmful radiation.

Other methods, such as CT scans, angiography, and myelography, are less effective for this specific evaluation.

Parameningeal Rhabdomyosarcoma is best assessed through imaging techniques. The most effective method for evaluation is:

• MRI - This scan provides detailed images of soft tissues and is excellent for examining tumours.
• CT scan - Useful for a quick overview and identifying the size and location of the tumour.
• SPECT - This technique is less common for this condition but can show blood flow and activity in tissues.
• PET - Helps detect cancer by highlighting areas of high metabolic activity.

Among these options, MRI is generally considered the best choice for a thorough evaluation of Parameningeal Rhabdomyosarcoma.

Cerebral blood flow can be accurately assessed in asphyxiated children using:

• NIRS (Near-Infrared Spectroscopy) - a non-invasive technique that measures blood flow and oxygenation in the brain.
• PET (Positron Emission Tomography) - provides detailed images of brain activity but is more complex and less commonly used for immediate assessment.
• Radionuclide imaging - involves injecting a small amount of radioactive material to evaluate blood flow but may not be the first choice in emergencies.
• MIlU angiography - a method for visualising blood vessels but is invasive and not typically used for routine assessments in children.

Among these methods, NIRS is preferred due to its non-invasive nature and real-time monitoring capabilities.

The X-ray findings associated with retinoblastoma typically include:

• Widening of the optic canal - This indicates possible involvement of the optic nerve.
• Intraocular calcification - This is a common finding in the affected eye.
• Secondaries in cranial bones - These may occur if the cancer spreads.

However, intracerebral calcification is not typically associated with retinoblastoma, making it an exception.

The best method to investigate parathyroid pathology is through a Tc ­Thallium subtraction scan. This imaging technique is effective in identifying abnormal parathyroid tissues, helping doctors to diagnose conditions such as hyperparathyroidism. It provides clear images and enhances the visibility of parathyroid glands, making it easier for healthcare professionals to assess any issues accurately.

The best view for seeing the sella turcica on an X-ray is:

• The lateral view provides the clearest image.
• This view shows the sella turcica's shape and size effectively.
• Other views, like the AP view or open mouth view, are less informative for this structure.

The patient has a six-month history of nasal discharge, facial pain, and fever, which improved temporarily with antibiotics but returned after one month. The symptoms now include mucopurulent discharge from the middle meatus, with the mucosa appearing congested and oedematous.

In this case, the next best investigation is:

• Non-contrast CT of the nose and paranasal sinuses.

This imaging technique is preferred because it provides detailed views of the sinus anatomy and can help identify any sinusitis or other abnormalities that may be causing the symptoms.

The rabbit ear sign appears on a CT scan when there are specific conditions affecting the brain. This sign is most commonly associated with:

• Bilateral subdural hematoma: This condition involves the accumulation of blood between the brain and its outer covering on both sides.
• Unilateral subdural hematoma: Blood collects on one side only, but this does not typically show the rabbit ear sign.
• Bilateral subarachnoid hemorrhage: This involves bleeding in the space surrounding the brain, but it is not linked to the rabbit ear sign.
• Unilateral subarachnoid hemorrhage: Similar to the bilateral form, this does not present the rabbit ear sign.

In summary, the rabbit ear sign is primarily seen in cases of bilateral subdural hematoma.

The bat wing deformity of the cerebral ventricles can be observed in specific medical conditions. Here are the key points regarding this deformity:

• This deformity is primarily associated with agenesis of the corpus callosum.
• It is characterised by a distinctive shape of the ventricles on imaging studies.
• Other conditions, such as bilateral subdural hematomas and subarachnoid haemorrhages, do not typically cause this deformity.
• Agenesis of cerebral ventricles is a different condition and not related to the bat wing appearance.

The “Face of the giant panda” sign observed in an MRI scan of the brain is typically associated with:

• Wilson’s disease: This is a genetic disorder leading to copper accumulation in the body, affecting the liver and brain.
• Japanese encephalitis: A viral infection that can cause inflammation of the brain, leading to various neurological symptoms.
• Rasmussen’s encephalitis: A rare condition that causes chronic inflammation in one hemisphere of the brain, often resulting in severe epilepsy.
• Wernicke’s encephalopathy: A neurological disorder caused by thiamine (vitamin B1) deficiency, often linked to alcohol misuse.

Among these, the sign is primarily seen in Wilson’s disease.

Von Hippel-Lindau (VHL) disease is associated with various types of tumours. Here are the common tumours linked to VHL disease:

• Endolymphatic sac tumours - These are often found in the inner ear.
• Pheochromocytomas - These are tumours of the adrenal glands that can cause high blood pressure.
• Islet cell tumours - These affect the pancreas and can disrupt insulin production.

However, mandibular osteomas are not typically associated with VHL disease. These are bone growths in the jaw and are unrelated to the condition.

The condition described involves a port-wine nevus, which is a type of birthmark that appears as a deep red discolouration on the skin. In this case, it is located on the forehead and left upper eyelid of a 16-year-old girl with complex partial seizures and mild learning difficulties.

A CT scan of the brain in such cases often reveals leptomeningeal angioma, which is a vascular malformation associated with the nevus. This type of angioma can lead to neurological symptoms, including seizures, due to its location and effect on surrounding brain tissue.

In summary, a CT scan would likely show signs of leptomeningeal angioma, reflecting the relationship between the skin lesion and the neurological condition.

When assessing potential cases of cerebro-vascular syncope, various tests are commonly used. Here are the relevant tests:

• Carotid Doppler: This test checks blood flow in the carotid arteries.
• MRI brain: This imaging technique provides detailed pictures of the brain to identify any abnormalities.
• MRA: This test creates images of blood vessels in the brain, helping to spot blockages or other issues.

However, an EEG, which measures electrical activity in the brain, is not typically used for diagnosing cerebro-vascular syncope.

The 'Light-bulb' sign observed in DWMRI is indicative of a specific medical condition. This sign is most commonly associated with the following:

• Hyperacute stroke: A type of stroke that occurs very quickly after the onset of symptoms, often within hours.
• Agarwal's disease, Vanishing bone disease, and Marchiafava-Bignami disease are less commonly related to this sign.

In summary, the presence of the 'Light-bulb' sign primarily points towards hyperacute stroke as the most relevant condition.

High-signal, oblong, or elliptical lesions located at the callososeptal interface and in the subependymal periventricular white matter are typically seen in specific conditions. These lesions appear oriented perpendicular to the ventricular surface on FLAIR and T2-weighted MR images.

• Multiple sclerosis: This condition is characterised by lesions due to the immune system attacking the central nervous system.
• Moya Moya disease: A rare disorder affecting blood vessels in the brain, leading to reduced blood flow and is not primarily associated with these lesions.
• Periventricular leukomalacia: Often seen in premature infants, this condition involves damage to the white matter around the ventricles but does not specifically match the lesion description.
• Posterior reversible encephalopathy syndrome: Characterised by headache, confusion, and visual disturbances, but the lesions described here are not typical for this syndrome.

Based on the imaging characteristics described, the most likely diagnosis is multiple sclerosis. This condition aligns with the findings of high-signal lesions in the specified regions.

The “salt-and-pepper” appearance seen in T1 MRI scans is characteristic of paragangliomas. This appearance consists of:

• Salt: Refers to the presence of subacute haemorrhages.
• Pepper: Indicates the existence of flow voids.

This combination helps in identifying the nature of the lesions in these tumours.

The symptoms described suggest a problem involving the right side of the brain or related structures. The mild right ptosis (drooping of the eyelid) and anisocoria (unequal pupil sizes) indicate possible nerve involvement.

• The right pupil is smaller than the left but reacts normally to light. This points towards a potential issue with the sympathetic nerve pathway.
• Given the acute onset of orbital pain and these symptoms, one likely cause could be related to the right carotid artery.
• An MRI is expected to show an increased T1 signal in the wall of the right carotid artery, indicating possible inflammation or other changes.

This suggests that the right carotid artery may be affected and warrants further investigation.