NEET-PG 2017 - Radiology Practice Questions

Q: A 25-year-old patient underwent surgery for scoliosis correction. 5 days post-operatively he develops voluminous bilious vomiting. The given CT abdomen shows:

SMA syndrome. ***SMA syndrome*** - The CT image shows significant **duodenal distention** proximal to the **superior mesenteric artery (SMA)**, characteristic of SMA syndrome. The arrow points to the **compressed third part of the duodenum** between the SMA and the aorta. - This condition is often seen post-scoliosis correction surgery due to rapid **spinal extension**, which can decrease the **aortomesenteric angle** and compress the duodenum, leading to **bilious vomiting**. *Paralytic ileus* - While ileus can cause vomiting and bowel distension, it typically involves **diffuse gaseous distension** of both small and large bowels without a discrete point of obstruction like the compressed duodenum seen here. - The clinical presentation of paralytic ileus post-operatively is more often characterized by generalized **absent bowel sounds** and abdominal distension, rather than specific bilious vomiting from high obstruction. *Pneumoperitoneum* - This refers to the presence of **free air in the abdominal cavity**, usually indicating a **visceral perforation**. - The provided CT image does not show any evidence of free air, and the presenting symptom of bilious vomiting is more indicative of obstruction. *Paravertebral abscess* - A paravertebral abscess would appear as a **fluid collection adjacent to the spine**, which is not depicted on this CT scan. - Clinical symptoms would likely include **fever, severe localized back pain**, and possibly neurological deficits, differing from the purely obstructive symptoms described.

Q: What is the radiological sign that could best describe this image?

Cobra head sign. ***Cobra head sign*** - This sign is seen in the setting of a **ureterocele**, which is a cystic dilatation of the intravesical (within the bladder) portion of the ureter. - On intravenous urography (IVU) or retrograde pyelography, the dilated ureterocele appears as a filling defect within the bladder, outlined by contrast, creating the characteristic "cobra head" or "spring onion" appearance. *Rim sign* - The **rim sign** is typically associated with **renal calculi** (kidney stones). - It refers to a thin rim of soft tissue or gas surrounding a radiolucent stone, which can sometimes be seen on CT scans. *Fish hook bladder* - This term describes the shape of the bladder in cases of **benign prostatic hyperplasia (BPH)**. - Due to the enlarged prostate elevating and distorting the bladder base, the contrast-filled bladder appears elongated and curved, resembling a fish hook on a cystogram. *Soap bubble* - The "soap bubble" appearance is often used to describe **multiloculated cystic masses** or certain types of tumors, particularly in bone lesions (e.g., aneurysmal bone cyst, fibrous dysplasia). - It refers to multiple small, rounded lucencies giving a bubbly or multicystic appearance on imaging.

Q: A 26-year-old construction worker with a previous history of recurrent kidney stones presents with flank pain. What is the radiological sign demonstrated in the IVP image shown below?

Rim sign. ***Rim sign*** - The image shows a **calcified rim around a radiolucent (non-calcified) center**, which is characteristic of a **calcium oxalate monohydrate stone** on an intravenous pyelogram (IVP). - This sign is also known as the **"lucent-centered calculus"** or **"target sign"** and indicates a partially calcified stone. *Ring sign* - The **ring sign** can refer to various appearances in medical imaging, often indicating a **ring-enhancing lesion** on CT or MRI, which is not applicable to a kidney stone on IVP. - In renal imaging, a ring sign might describe a collection of contrast medium around a tumor or cyst, but not typically a stone with a radiolucent center. *Egg in cup appearance* - This sign is typically associated with **osteochondroma or enchondroma** lesions in bone imaging, where the cartilage cap creates a "cup" for the medullary bone to grow into. - It is not a recognized sign for kidney stones. *Sun burst appearance* - The **sun burst appearance** is characteristic of certain **bone tumors**, particularly **osteosarcoma**, where new bone forms perpendicular to the bone surface. - This description does not apply to the radiological features of kidney stones on IVP.

Q: Which of the following is correct about the NCCT shown below? (Recent NEET Pattern 2016-17)

Intraparenchymal hemorrhage. ***Intraparenchymal hemorrhage*** - The image shows a **hyperdense (bright)** lesion within the brain parenchyma, indicated by the arrows. This appearance on non-contrast CT (NCCT) is characteristic of **acute hemorrhage** (blood) within the brain tissue. - The location and morphology are consistent with blood accumulating directly within the brain substance rather than in the subarachnoid space or as a diffuse cerebral edema. *Acute ischemic stroke* - An **acute ischemic stroke** on NCCT typically appears as a **hypodense (darker)** area due to **edema** and cell death, usually after several hours. The lesion shown in the image is hyperdense. - Early signs of acute ischemic stroke (within the first few hours) can include subtle changes like loss of gray-white matter differentiation or hyperdense vessel signs, but not a distinct hyperdense parenchymal lesion as seen here. *Acute hemorrhagic stroke* - While technically a hemorrhagic stroke, this option is too broad. Hemorrhagic stroke encompasses both intraparenchymal hemorrhage and subarachnoid hemorrhage. - The specific location of the blood within the brain tissue, as opposed to solely in the subarachnoid space, makes "intraparenchymal hemorrhage" a more precise diagnosis. *Subarachnoid hemorrhage* - **Subarachnoid hemorrhage (SAH)** would appear as hyperdensity (blood) in the **sulci, fissures**, and **basal cisterns** surrounding the brain, not within the brain parenchyma itself. - The image clearly shows the lesion within the brain tissue, not in the subarachnoid spaces.

Q: All are true about CNS malformation shown below except:

Large posterior fossa. ***Large posterior fossa*** - The image shown, consistent with a **Chiari II malformation**, typically features a **small posterior fossa**, not a large one. - A small posterior fossa contributes to the crowding and herniation of cerebellar structures through the foramen magnum. *Herniation of cerebellar tonsil* - **Chiari II malformation** is characterized by the **downward displacement of the cerebellar tonsils** through the foramen magnum. - This herniation can lead to obstruction of CSF flow and associated neurological symptoms. *Herniation of cerebellar vermis* - The image suggests a **Chiari II malformation**, which involves the **caudal displacement of the cerebellar vermis** and fourth ventricle into the spinal canal. - This is a hallmark feature distinguishing it from other Chiari malformations. *Association with myelomeningocele* - **Chiari II malformation** has a strong and consistent association with **myelomeningocele**, a severe form of spina bifida. - Most patients with myelomeningocele will also have a Chiari II malformation, indicating a common developmental origin.

Q: A 2-year-old epileptic child with developmental delay presents to emergency with fever for the last two days. NCCT shows:

Lissencephaly. ***Lissencephaly*** - The image shows a **smooth brain surface** with **absent or reduced gyri and sulci**, which is characteristic of lissencephaly. - This condition is often associated with **developmental delay** and **epilepsy**, consistent with the child's presentation. *Subdural hemorrhage* - A subdural hemorrhage would appear as a **crescent-shaped collection of blood** between the dura mater and arachnoid mater. - The image does not demonstrate any such blood collection. *Arnold-Chiari malformation* - Arnold-Chiari malformation involves the downward displacement of the **cerebellar tonsils** into the foramen magnum. - While it can cause neurological symptoms, the primary finding in the image is a smooth cerebral cortex, not cerebellar displacement. *Schizencephaly* - Schizencephaly is characterized by **clefts or slits in the cerebral hemispheres** that extend from the pial surface to the ventricles. - The image shows a smooth brain surface rather than distinct full-thickness clefts.

Q: A 79-year-old male presented to the emergency department after a facial trauma. The patient had Parkinson's disease and atrial fibrillation and was on treatment with acetylsalicylic acid for AF. The image shows? (Recent NEET Pattern 2016-17)

Pneumocephalus. ***Pneumocephalus*** - The image clearly shows **intracranial air** (dark areas within the brain parenchyma and ventricles, indicated by arrows) following facial trauma, consistent with **pneumocephalus**. - **Pneumocephalus** often results from fractures of the skull base or paranasal sinuses, especially after trauma, allowing air to enter the intracranial space. *Hydrocephalus* - **Hydrocephalus** involves enlargement of the **ventricles** due to an accumulation of cerebrospinal fluid, which would appear as dark, but *fluid-filled* spaces, not air-filled. - No signs of significantly dilated ventricles are observed; instead, distinct air pockets are visible, which look black on CT. *Intraventricular bleed* - An **intraventricular bleed** would appear as **hyperdense (bright)** material (blood) within the ventricles on a CT scan, which is not seen here. - The appearance of the abnormalities is **hypodense (black)**, indicating air, not blood. *Subarachnoid hemorrhage* - **Subarachnoid hemorrhage** is characterized by **hyperdense (bright)** blood filling the subarachnoid spaces, particularly the sulci and basal cisterns. - The image displays **hypodense** areas consistent with air within the brain, not diffuse bright areas of blood in the subarachnoid space.

Q: What is the correct diagnosis based on the image shown below?

Dense MCA sign. ***Dense MCA sign*** - The image displays a hyperdense (bright) appearance of the **Middle Cerebral Artery (MCA)**, particularly noticeble in the Sylvian fissure on the left side (indicated by the shorter arrow). This is highly suggestive of a **thrombus within the MCA lumen**, one of the earliest signs of an acute ischemic stroke on non-contrast CT [1]. - This finding is a strong indicator of **large vessel occlusion** and is crucial for guiding acute stroke management, such as the administration of thrombolytics or mechanical thrombectomy [1]. *Lacunar stroke* - Lacunar strokes are typically **small, deep infarcts** caused by occlusion of small penetrating arteries, which are not directly visible as a hyperdense vessel sign on non-contrast CT [3]. - The image shows a larger-scale vascular finding, not a small, isolated infarct characteristic of a lacunar stroke [3]. *Subarachnoid hemorrhage* - Subarachnoid hemorrhage (SAH) appears as **high-density blood** filling the subarachnoid spaces, fissures, and sulci [2]. - While the image shows some hyperdensity, it is specifically confined to a major arterial structure (MCA), not diffuse within the subarachnoid space as seen in SAH. *Intraventricular hemorrhage* - Intraventricular hemorrhage (IVH) is characterized by **hyperdense blood within the ventricular system** of the brain [2]. - The image does not show blood within the ventricles; the hyperdensity is clearly located along the course of a major cerebral artery. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Central Nervous System, pp. 1266-1268. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Manifestations Of Central And Peripheral Nervous System Disease, pp. 706-707. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Central Nervous System, pp. 1269-1270.

Q: A 55-year-old diabetic patient develops sudden onset hemiparesis and facial asymmetry. NCCT scan shows:

Hyperdense MCA sign. ***Hyperdense MCA sign*** - The image exhibits a **bright (hyperdense) area** within the Sylvian fissure, indicated by the white arrow, representing a **thrombus occluding the middle cerebral artery (MCA)**. This is a direct sign of acute **ischemic stroke**. - Clinical presentation of sudden onset hemiparesis and facial asymmetry in a diabetic patient strongly suggests an **ischemic stroke**, and the hyperdense MCA sign on NCCT confirms a proximal vessel occlusion. *Cystic encephalomalacia* - This refers to the **end stage of an infarct**, where brain tissue is replaced by **CSF-filled cysts** and gliosis, appearing as hypodense areas. - This finding would indicate an **old stroke**, not an acute event causing sudden neurological deficits. *Subarachnoid hemorrhage* - This condition involves **blood in the subarachnoid space**, appearing as hyperdensity within the **sulci and basal cisterns**. - While it features hyperdensity, the location in the image (within the Sylvian fissure, consistent with MCA) and the patient's symptoms are not typical for isolated subarachnoid hemorrhage. *Lobar hemorrhage* - A lobar hemorrhage is an **intraparenchymal bleed** within a lobe of the brain, appearing as a **focal, well-defined hyperdense lesion within the brain parenchyma**. - The hyperdensity in the image is linear and located within a vascular structure, consistent with an occluded vessel rather than a parenchymal bleed.

Question 1

A 25-year-old patient underwent surgery for scoliosis correction. 5 days post-operatively he develops voluminous bilious vomiting. The given CT abdomen shows:

Accepted Answer

SMA syndrome

Answer

Paralytic ileus

Answer

Pneumoperitoneum

Answer

Paravertebral abscess

Question 2

Excretory urogram in a two-year-old child with recurrent UTI shows:

Accepted Answer

Drooping water lily sign

Answer

Horse shoe kidney

Answer

Flower vase kidney

Answer

Duplication of kidney

Question 3

What is the radiological sign that could best describe this image?

Accepted Answer

Cobra head sign

Answer

Rim sign

Answer

Fish hook bladder

Answer

Soap bubble

Question 4

A 26-year-old construction worker with a previous history of recurrent kidney stones presents with flank pain. What is the radiological sign demonstrated in the IVP image shown below?

Accepted Answer

Rim sign

Answer

Ring sign

Answer

Egg in cup appearance

Answer

Sun burst appearance

Question 5

Which of the following is correct about the NCCT shown below? (Recent NEET Pattern 2016-17)

Accepted Answer

Intraparenchymal hemorrhage

Answer

Acute ischemic stroke

Answer

Acute hemorrhagic stroke

Answer

Subarachnoid hemorrhage

Question 6

All are true about CNS malformation shown below except:

Accepted Answer

Large posterior fossa

Answer

Herniation of cerebellar tonsil

Answer

Herniation of cerebellar vermis

Answer

Association with myelomeningocele

Question 7

A 2-year-old epileptic child with developmental delay presents to emergency with fever for the last two days. NCCT shows:

Accepted Answer

Lissencephaly

Answer

Subdural hemorrhage

Answer

Arnold-Chiari malformation

Answer

Schizencephaly

Question 8

A 79-year-old male presented to the emergency department after a facial trauma. The patient had Parkinson's disease and atrial fibrillation and was on treatment with acetylsalicylic acid for AF. The image shows? (Recent NEET Pattern 2016-17)

Accepted Answer

Pneumocephalus

Answer

Hydrocephalus

Answer

Intraventricular bleed

Answer

Subarachnoid hemorrhage

Question 9

What is the correct diagnosis based on the image shown below?

Accepted Answer

Dense MCA sign

Answer

Lacunar stroke

Answer

Subarachnoid hemorrhage

Answer

Intraventricular hemorrhage

Question 10

A 55-year-old diabetic patient develops sudden onset hemiparesis and facial asymmetry. NCCT scan shows:

Accepted Answer

Hyperdense MCA sign

Answer

Cystic encephalomalacia

Answer

Subarachnoid hemorrhage

Answer

Lobar hemorrhage

NEET-PG 2017 — Radiology