KMU Past Paper Practice

Question:

A 38-year-old man has sudden severe flank pain radiating towards the groin and microscopic haematuria. He is stable, and a ureteric calculus is suspected. Which examination best identifies the stone and its level?

Correct Answer: Non-contrast CT abdomen and pelvis

Explanation: CT without intravenous contrast can show a ureteric stone and its location; intravenous contrast is unnecessary for this initial stone question.

Question:

A woman at 24 weeks of pregnancy develops acute flank pain. The clinician wants to assess the kidneys for obstruction while selecting an appropriate initial examination. Which choice best fits the situation?

Correct Answer: Renal and bladder ultrasound

Explanation: Ultrasound can assess the collecting system for dilatation without ionizing radiation. A limited result may require further evaluation.

Question:

A patient has jaundice and a dilated bile duct on ultrasound. The team needs a non-invasive examination that shows the biliary ducts in detail. Which technique is most suitable?

Correct Answer: Magnetic resonance cholangiopancreatography

Explanation: This MRI technique depicts fluid-filled biliary ducts and can help locate obstruction without an invasive procedure.

Question:

A patient has a tender superficial swelling. The surgeon wants to distinguish a fluid collection from solid tissue and guide a needle towards any collection at the bedside. Which technique best meets both needs?

Correct Answer: Real-time ultrasound

Explanation: Ultrasound distinguishes fluid from surrounding tissue and shows the needle during bedside guidance.

Question:

A stable patient with new focal weakness has undergone initial emergency assessment. Early brain ischaemia remains suspected despite a CT that shows no clear infarct. Which technique is particularly useful for detecting early ischaemic tissue change?

Correct Answer: Diffusion-weighted brain MRI

Explanation: Diffusion-weighted MRI is sensitive to early changes in ischaemic brain tissue when the initial CT is inconclusive.

Question:

A small opacity on a frontal chest radiograph cannot be confidently placed in the anterior or posterior chest. Which additional plain radiographic view would help localise it?

Correct Answer: Lateral chest radiograph

Explanation: A second projection adds depth information that a frontal projection alone cannot provide.

Question:

A stable patient has suspected pulmonary embolism, but the imaging team advises against intravenous iodinated contrast for this patient. The chest radiograph is unremarkable. Which alternative investigation can assess pulmonary ventilation and perfusion?

Correct Answer: Ventilation–perfusion lung scan

Explanation: A ventilation–perfusion scan can investigate suspected pulmonary embolism when CT pulmonary angiography is unsuitable; it still uses ionizing radiation.

Question:

During a lung ventilation–perfusion examination, one region has reduced perfusion while ventilation is preserved. Which interpretation best explains why the finding may support pulmonary embolism?

Correct Answer: Blood flow is reduced despite air reaching the region

Explanation: An embolus can reduce blood flow to a ventilated region, producing a ventilation–perfusion mismatch.

Question:

A stable patient has a penetrating thigh injury. Examination raises concern for arterial damage, and the surgical team needs to locate a possible vessel injury before treatment. Which technique is most directly suited to this question?

Correct Answer: CT angiography of the injured limb

Explanation: Intravenous contrast allows CT angiography to show the arterial lumen and locate an injury in a stable patient.

Question:

A patient has persistent vomiting, abdominal distension, and suspected bowel obstruction. An abdominal radiograph suggests dilated bowel, but the surgeon needs to locate the obstruction and assess its cause. Which technique adds the most useful anatomical detail?

Correct Answer: Perform CT of the abdomen and pelvis

Explanation: CT provides cross-sectional detail that can identify the level and possible cause of bowel obstruction.

Question:

A radiology worker wears a personal dosimeter during procedures involving X-rays. What is its principal purpose?

Correct Answer: Monitor the worker’s occupational exposure

Explanation: A dosimeter records exposure for monitoring; it does not itself shield the wearer.

Question:

During a fluoroscopic procedure, a staff member must remain in the room near the patient. Which item directly reduces radiation reaching the staff member’s covered torso?

Correct Answer: Protective lead apron

Explanation: A protective apron attenuates scattered X-rays reaching covered parts of the body.

Question:

A fluoroscopic procedure requires intermittent views of a slowly moving instrument. The operator selects an appropriate pulsed setting instead of continuous imaging. What is the main radiation-protection benefit?

Correct Answer: Fewer X-ray exposures are used per unit time

Explanation: An appropriate pulse rate can reduce the number of X-ray exposures while retaining adequate procedural guidance.

Question:

A patient has a suspected pleural fluid collection. The clinician wants to confirm that fluid is present and identify a suitable site for a bedside procedure. Which examination best addresses both questions?

Correct Answer: Thoracic ultrasound

Explanation: Ultrasound can show pleural fluid at the bedside and help select a safe procedural site.

Question:

A patient has focal wrist tenderness after a fall. The first radiograph shows overlapping bones, making alignment difficult to assess. Which change would best improve the plain radiographic assessment?

Correct Answer: Obtain an orthogonal radiographic view

Explanation: A view from a different direction helps separate overlapping structures and assess alignment.

Question:

A patient with a suspected occult bone injury has persistent focal pain despite radiographs that show no clear fracture. The clinician wants to assess bone marrow and nearby soft tissues. Which technique provides this information best?

Correct Answer: Magnetic resonance imaging of the area

Explanation: MRI can show marrow changes and associated soft-tissue injury that may be occult on initial radiographs.

Question:

An imaging request asks for an examination of a small area, but the proposed CT protocol includes the chest, abdomen, and pelvis. No clinical concern is documented outside the small target area. What should be clarified before scanning?

Correct Answer: Whether the scan range can match the clinical question

Explanation: Matching the scanned area to the clinical question avoids irradiating regions that do not need assessment.

Question:

A patient asks whether the contrast agents commonly used for enhanced CT and enhanced MRI are the same substance. Which response correctly distinguishes them?

Correct Answer: CT commonly uses iodine and MRI uses gadolinium

Explanation: Intravenous CT contrast is commonly iodine-based; MRI contrast, when indicated, is commonly gadolinium-based.

Question:

A patient asks why staff use protective barriers while the patient must undergo an indicated X-ray examination. Which explanation best distinguishes the two exposure situations?

Correct Answer: The patient receives a justified medical exposure; staff avoid unnecessary occupational exposure

Explanation: The patient’s examination aims to provide a medical benefit. Barriers reduce avoidable exposure to staff who work around radiation repeatedly.

Question:

At an integrated imaging OSPE station, a student is given three details: the target structure, the urgency of the patient’s condition, and whether an imaging result will alter treatment. What is the best reason to consider these details together?

Correct Answer: They guide a justified and suitable imaging choice

Explanation: The target tissue, urgency, and likely effect on care determine whether to image and which technique is appropriate.