NEET-PG 2013 - Radiology PYQs Practice Questions

Q: Which of the following is used in the treatment of well-differentiated thyroid carcinoma?

I131. ***I131*** - **Radioactive iodine (I131)** is specifically absorbed by **well-differentiated thyroid cancer cells** because these cells retain the ability to uptake iodine, unlike other types of cancer cells. - Used for **ablating residual thyroid tissue** after surgery and for treating **metastatic well-differentiated thyroid carcinoma** [1]. *99m Tc* - **Technetium-99m (99m Tc)** is primarily used for **diagnostic imaging** (e.g., thyroid scans, bone scans), not for therapeutic treatment of thyroid cancer. - It has a short half-life and emits gamma rays, making it suitable for imaging but generally not for delivering sustained radiation for therapeutic effect. *32p* - **Phosphorus-32 (32p)** is a beta-emitting radionuclide used in the treatment of certain hematological malignancies, such as **polycythemia vera**, and for palliative treatment of bone metastases. - It is not selectively taken up by thyroid cancer cells and therefore is not used in the treatment of thyroid carcinoma. *MIBG* - **Metaiodobenzylguanidine (MIBG)**, often labeled with I123 (diagnostic) or I131 (therapeutic), is used in the diagnosis and treatment of **neuroendocrine tumors** like **pheochromocytoma** and **neuroblastoma**. - Its uptake mechanism targets cells of neuroectodermal origin, which is distinct from the iodine uptake mechanism of thyroid cells. [Practice more Radiology PYQs on OnCourse]

Q: Inferior rib notching is seen in which of the following conditions?

Coarctation of the aorta. ***Coarctation of the aorta*** - **Inferior rib notching** is a classic radiographic sign caused by the **enlarged, tortuous intercostal arteries** eroding the inferior margins of the ribs. - This collateral circulation develops to bypass the narrowed aortic segment, increasing blood flow through the intercostal arteries. *Rickets* - Rickets can cause **bowing of long bones**, widened epiphyseal plates, and a **rachitic rosary** (enlargement of costochondral junctions). - It does not typically lead to rib notching; rather, it affects bone mineralization and growth patterns. *ASD* - An **atrial septal defect (ASD)** is a congenital heart defect causing a left-to-right shunt, leading to pulmonary overload and right heart enlargement. - While it can manifest with cardiomegaly and increased pulmonary vascular markings, it does not cause rib notching. *Multiple myeloma* - Multiple myeloma is a plasma cell malignancy that causes **punched-out lytic lesions** in bones, leading to bone pain and pathological fractures. - While it affects bone, the lesions are typically osteolytic and diffuse, not specifically causing inferior rib notching. [Practice more Radiology PYQs on OnCourse]

Q: A chest X-ray shows bilateral lung infiltrates. What is the next best investigation?

CT. ***CT*** - A **CT scan (preferably HRCT)** provides a more detailed view of the lung parenchyma, allowing for better characterization of the infiltrates (e.g., location, pattern, presence of nodules, ground-glass opacities, or consolidation). - This detailed imagery is crucial for narrowing down the differential diagnosis and guiding further diagnostic or therapeutic interventions. - **CT is the best next investigation** for characterizing bilateral lung infiltrates seen on chest X-ray. *Sputum examination* - While important for identifying infectious causes, **sputum examination** is often only productive in certain types of pneumonia or infections and might not directly clarify the morphology or distribution of the infiltrates as a CT scan would. - It might be a subsequent step once the nature of the infiltrate is better understood through imaging. *Bronchoscopy* - **Bronchoscopy** is an invasive procedure generally reserved for cases where less invasive methods have failed to yield a diagnosis or when specific findings from imaging (like a CT scan) suggest the need for direct visualization, lavage, or biopsy. - It's not typically the immediate next step after identifying bilateral infiltrates on a chest X-ray. *Echocardiography* - **Echocardiography** is useful for evaluating cardiac causes of bilateral infiltrates (such as pulmonary edema from heart failure). - However, it does not directly visualize or characterize the lung parenchymal infiltrates themselves, making CT more valuable as the next investigation. [Practice more Radiology PYQs on OnCourse]

Q: The most accurate investigation for assessing ventricular function is:

MRI. ***MRI*** - Cardiac MRI is considered the **gold standard** for assessing ventricular function, providing highly accurate and reproducible measurements of **ventricular volumes**, **ejection fraction**, and **myocardial mass**. - It offers excellent tissue characterization, allowing for direct visualization of **fibrosis**, **inflammation**, and other myocardial pathologies that can affect function. *Multislice CT* - While useful for assessing cardiac anatomy, particularly **coronary arteries**, Multislice CT involves **ionizing radiation** and has limitations in accurately assessing subtle changes in myocardial function compared to MRI. - Its strength lies more in **anatomical evaluation** (e.g., calcium scoring, coronary angiography) rather than detailed functional assessment. *Echocardiography* - Echocardiography is a widely available and useful first-line imaging modality for ventricular function, but it can be limited by **acoustic windows**, **operator dependency**, and **spatial resolution** compared to MRI. - While it provides good estimates of ejection fraction, particularly in simple cases, its 3D capabilities and tissue characterization are generally inferior to MRI. *Nuclear scan* - Nuclear scans (e.g., MUGA scans, SPECT) can assess ventricular function and myocardial perfusion, but they involve **ionizing radiation** and primarily provide **functional information** based on tracer uptake, not detailed structural or tissue characterization. - They are often used for evaluating **perfusion defects** and overall ejection fraction, but are less precise for detailed chamber quantification and tissue characterization than MRI. [Practice more Radiology PYQs on OnCourse]

Q: The procedure of choice for the evaluation of aortic aneurysms is -

Computed tomography. ***Computed tomography*** - **Computed tomography (CT)** offers excellent spatial resolution and is the gold standard for diagnosing, staging, and pre-operative planning for aortic aneurysms. - It precisely measures aneurysm size, detects mural thrombus, assesses rupture risk, and evaluates the extent of involvement with surrounding structures. *Ultrasonography* - While useful for initial screening and serial monitoring of known abdominal aortic aneurysms due to its non-invasiveness and cost-effectiveness, its accuracy can be limited by **patient body habitus** and **bowel gas**. - It may not reliably visualize the entire aorta or accurately assess complex anatomy and rupture. *Magnetic resonance imaging* - **Magnetic resonance imaging (MRI)** provides detailed anatomical information and avoids radiation exposure, but it is typically more expensive and time-consuming than CT. - It is often reserved for patients with **renal insufficiency** where iodinated contrast is a concern or when evaluating specific tissue characteristics not well seen on CT. *Arteriography* - **Arteriography** (angiography) is an invasive procedure involving direct contrast injection, carrying risks such as arterial injury and nephrotoxicity. - While it can visualize the aortic lumen, it primarily shows the patent lumen and may **underestimate the true aneurysm size** due to mural thrombus. It is typically used for intervention planning or specific contexts rather than initial diagnosis. [Practice more Radiology PYQs on OnCourse]

Question 1

Which of the following is used in the treatment of well-differentiated thyroid carcinoma?

Accepted Answer

I131

Answer

99m Tc

Answer

32p

Answer

MIBG

Question 2

Inferior rib notching is seen in which of the following conditions?

Accepted Answer

Coarctation of the aorta

Answer

Rickets

Answer

ASD

Answer

Multiple myeloma

Question 3

A chest X-ray shows bilateral lung infiltrates. What is the next best investigation?

Accepted Answer

CT

Answer

Sputum examination

Answer

Bronchoscopy

Answer

Echocardiography

Question 4

The most accurate investigation for assessing ventricular function is:

Accepted Answer

MRI

Answer

Multislice CT

Answer

Echocardiography

Answer

Nuclear scan

Question 5

The procedure of choice for the evaluation of aortic aneurysms is -

Accepted Answer

Computed tomography

Answer

Magnetic resonance imaging

Answer

Arteriography

Answer

Ultrasonography

Question 6

Retrocardiac lucency with air fluid level is seen in

Accepted Answer

Hiatus hernia

Answer

Distal esophageal obstruction

Answer

Diaphragmatic eventration

Answer

None of the options

Question 7

Which CT view is best for visualizing paranasal polyps?

Accepted Answer

Coronal view

Answer

Axial view

Answer

Sagittal view

Answer

3D view

Question 8

Tear drop sign is seen in?

Accepted Answer

Blow out fracture

Answer

Fracture zygomatic arch

Answer

Fracture maxilla

Answer

Fracture mandible

Question 9

Which condition is characterized by a specific radiological appearance resembling a sunburst pattern?

Accepted Answer

Osteosarcoma

Answer

Chondrosarcoma

Answer

Fibrosarcoma

Answer

Ewing's sarcoma

Question 10

What is the best imaging view for assessing the nasal bone in X-ray?

Accepted Answer

Lateral

Answer

Towne's

Answer

Submentovertical

Answer

Caldwell

NEET-PG 2013 — Radiology