HESI Radiology Exit Exam prep Version 1 Exam
Questions and Answers Practice Questions with
Solutions Newest | Already Graded A+
1. A radiographer is performing a portable chest radiograph on a patient in the intensive care unit.
The patient is on a mechanical ventilator and has multiple chest tubes. The radiographer notices
that the automatic exposure control (AEC) chambers are not positioned correctly due to the
patient's supine position and the presence of tubes. Which of the following actions is most
appropriate to ensure optimal image quality while minimizing patient dose?
A. Increase the mAs by 50% and disable the AEC to manually set exposure.
B. Select the center AEC chamber and increase the kVp by 15% to compensate for the increased tissue
thickness.
C. Use the AEC with the left and right chambers selected and manually adjust the density setting to +2.
D. Disable the AEC and use a technique chart based on the patient's body habitus, ensuring the exposure index
falls within the acceptable range.
Answer: D
Rationale: Disabling AEC and using a technique chart is appropriate when AEC chambers cannot be
positioned correctly, as it ensures consistent exposure and avoids overexposure. Option A increases mAs
without addressing the chamber issue, potentially increasing dose. Option B is incorrect because
increasing kVp with AEC may not correct chamber misalignment. Option C may still result in incorrect
exposure due to improper chamber placement.
2. A radiologist is evaluating a digital radiograph of the knee obtained with a computed
radiography (CR) system. The image demonstrates quantum mottle, but the exposure index is
within the manufacturer's recommended range. Which of the following is the most likely cause of
the quantum mottle?
A. Use of a grid with a grid ratio that is too high for the CR system.
B. Insufficient mAs despite a normal exposure index due to incorrect calibration of the reader.
C. Excessive kVp causing increased scatter radiation reaching the detector.
D. Patient motion during the exposure, resulting in blur and reduced signal.
Answer: B
Rationale: Quantum mottle is caused by insufficient x-ray photons reaching the detector. A normal
exposure index may be misleading if the CR reader is calibrated incorrectly, as it could indicate a
higher exposure than actually occurred. Option A (high grid ratio) reduces scatter but also reduces
primary beam, which could cause mottle, but the exposure index would likely be low. Option C
(excessive kVp) increases scatter but also increases detector signal, reducing mottle. Option D (motion)
causes blur, not mottle.
Page 1
,3. During a fluoroscopic procedure, the radiographer notices that the automatic brightness control
(ABC) is causing the kVp to increase to 120 kVp and the mA to decrease to 0.5 mA for a patient
with a large body habitus. The image quality is suboptimal due to excessive noise. Which of the
following adjustments should the radiographer make to improve image quality while maintaining
patient dose as low as reasonably achievable (ALARA)?
A. Increase the mA manually to 2 mA and allow the ABC to adjust kVp accordingly.
B. Select a lower kVp (e.g., 80 kVp) and increase the mA to maintain a constant exposure rate.
C. Use the pulsed fluoroscopy mode at 15 pulses per second instead of continuous mode.
D. Increase the source-to-image distance (SID) to reduce patient dose and improve image quality.
Answer: B
Rationale: Selecting a lower kVp and increasing mA reduces noise because mA directly affects the
number of photons. This approach maintains exposure rate and improves image quality, though it may
increase patient dose if not carefully balanced. Option A (increasing mA alone) may cause the ABC to
lower kVp further, but the ABC's response is unpredictable. Option C (pulsed mode) reduces dose but
may not improve noise. Option D (increasing SID) reduces dose but also reduces image intensity,
potentially requiring higher technique.
4. A radiographer is performing a CT examination of the abdomen and pelvis with intravenous
contrast. The patient has a history of mild allergic reaction to iodinated contrast media (urticaria).
According to current guidelines, which of the following premedication regimens is most
appropriate for this patient?
A. Prednisone 50 mg orally 13 hours, 7 hours, and 1 hour before contrast administration, plus diphenhydramine
50 mg orally 1 hour before.
B. Methylprednisolone 40 mg orally 12 hours and 2 hours before contrast, plus diphenhydramine 50 mg
intravenously immediately prior.
C. Hydrocortisone 200 mg intravenously 4 hours and 1 hour before contrast, plus famotidine 20 mg
intravenously 1 hour before.
D. No premedication is necessary; administer nonionic low-osmolar contrast and monitor closely.
Answer: A
Rationale: The recommended premedication for a patient with a prior mild allergic reaction includes a
three-dose regimen of corticosteroids (e.g., prednisone 50 mg orally at 13, 7, and 1 hour before) and
diphenhydramine 50 mg orally 1 hour before. Option B uses methylprednisolone but the timing is
nonstandard. Option C uses intravenous hydrocortisone and H2 blocker, which is not first-line. Option
D is incorrect because premedication is indicated for prior reactions.
5. A radiographer is positioning a patient for a lateral projection of the lumbar spine. The patient
has scoliosis with a convexity to the right. The radiographer aligns the central ray perpendicular to
the image receptor and directs it to the iliac crest. Which of the following modifications should be
made to improve visualization of the intervertebral foramina?
A. Angle the central ray 15 degrees caudad and direct it to the level of L3.
B. Angle the central ray 15 degrees cephalad and direct it to the level of L4.
C. Increase the SID to 72 inches and use a grid with a higher ratio.
D. Position the patient with the left side down and use a 20-degree wedge filter.
Page 2
,Answer: B
Rationale: In scoliosis, the spine is rotated; to open the intervertebral foramina on the side of convexity
(right), the central ray should be angled cephalad to align with the foramina. Option B (15 degrees
cephalad at L4) is appropriate for the lumbar spine. Option A (caudad) would close the foramina.
Option C (increased SID) improves detail but does not address foramina visualization. Option D (wedge
filter) may help with density but not foramina opening.
6. A radiographer is performing a barium enema study on a patient with suspected diverticulitis.
During the procedure, the radiographer observes extravasation of contrast medium outside the
colonic lumen. Which of the following is the most appropriate immediate action?
A. Continue the study to document the extent of extravasation and notify the radiologist.
B. Stop the procedure immediately, monitor the patient's vital signs, and notify the radiologist and referring
physician.
C. Reduce the flow rate of barium and switch to a water-soluble contrast medium to decrease risk of peritonitis.
D. Administer intravenous glucagon to reduce colonic spasm and prevent further extravasation.
Answer: B
Rationale: Extravasation of contrast indicates a perforation, which is a medical emergency. The
procedure must be stopped immediately to prevent further leakage. The patient should be monitored for
signs of peritonitis and the physician notified. Option A is dangerous as continuing may worsen the
condition. Option C is inappropriate because any contrast extravasation is harmful. Option D does not
address the perforation.
7. A radiographer is evaluating a digital mammogram and notices a cluster of microcalcifications
in the upper outer quadrant of the left breast. The microcalcifications are pleomorphic and linear,
with some branching. According to the BI-RADS lexicon, which of the following is the most
appropriate assessment category?
A. BI-RADS 3: Probably benign.
B. BI-RADS 4C: High suspicion for malignancy.
C. BI-RADS 5: Highly suggestive of malignancy.
D. BI-RADS 0: Incomplete, need additional imaging evaluation.
Answer: B
Rationale: Pleomorphic, linear, and branching microcalcifications are characteristic of ductal carcinoma
in situ (DCIS) and are considered highly suspicious. BI-RADS 4C is used for findings with a high
suspicion of malignancy (50-95% likelihood). BI-RADS 5 is reserved for findings with 95% likelihood,
typically including spiculated masses. Option A (BI-RADS 3) is for probably benign findings with <2%
malignancy risk. Option D (BI-RADS 0) is for incomplete studies needing additional views.
8. A radiographer is performing a nuclear medicine bone scan on a patient with prostate cancer.
The patient has a serum creatinine level of 2.5 mg/dL. Which of the following modifications to the
imaging protocol is most appropriate?
A. Administer the standard dose of Tc-99m MDP and encourage increased fluid intake.
B. Reduce the administered activity of Tc-99m MDP by 50% and extend the imaging time.
C. Use Tc-99m HDP instead of MDP because of its faster renal clearance.
Page 3
, D. Delay the study until renal function improves, as the radiopharmaceutical is contraindicated.
Answer: A
Rationale: A serum creatinine of 2.5 mg/dL indicates moderate renal impairment, but Tc-99m MDP is
still safe. The standard dose can be given with increased hydration to promote clearance. Option B
(reducing activity) may degrade image quality. Option C (HDP) has similar renal clearance and does
not offer advantage. Option D (delaying) is unnecessary as the study can be performed with appropriate
hydration.
9. A radiographer is reviewing a chest radiograph and notes a right-sided pneumothorax with the
lung edge visible at the level of the lateral third rib. The patient is asymptomatic. According to the
British Thoracic Society guidelines, which of the following is the most appropriate management?
A. Immediate needle decompression followed by chest tube insertion.
B. Observation and repeat chest radiograph in 4-6 hours.
C. Administer high-flow oxygen and perform CT scan for further evaluation.
D. Perform thoracentesis to remove the air and re-expand the lung.
Answer: B
Rationale: A small pneumothorax in an asymptomatic patient can be managed conservatively with
observation. The lung edge at the lateral third rib indicates a small pneumothorax. Option A is for
tension pneumothorax or large symptomatic pneumothorax. Option C (high-flow oxygen) may be used to
accelerate resorption but is not first-line. Option D (thoracentesis) is not indicated for pneumothorax.
10. A radiographer is performing a quality control test on a digital radiography system. The test
involves exposing a uniform phantom and measuring the mean pixel value and standard deviation.
The resulting signal-to-noise ratio (SNR) is 50. If the exposure is doubled, what will be the new
SNR?
A. 25
B. 35
C. 71
D. 100
Answer: C
Rationale: SNR is proportional to the square root of the number of photons, which is proportional to
exposure. Doubling exposure increases SNR by a factor of sqrt(2) 1.414. Thus, new SNR = 50 * 1.414
70.7, rounding to 71. Option A (25) is half, which would occur if SNR decreased. Option B (35) is
incorrect. Option D (100) would require a 4-fold increase in exposure.
11. A radiograph of the abdomen demonstrates a ground-glass appearance with loss of psoas
margins and indistinct liver and splenic contours. A small amount of free intraperitoneal air is
noted under the right hemidiaphragm. Which of the following best explains the combination of
findings?
A. Ruptured hollow viscus with massive intraperitoneal fluid
B. Perforated gastric ulcer with pneumoperitoneum and ascites
C. Superior mesenteric artery syndrome with gastric dilatation
D. Pancreatitis with retroperitoneal air tracking into the peritoneum
Page 4
Questions and Answers Practice Questions with
Solutions Newest | Already Graded A+
1. A radiographer is performing a portable chest radiograph on a patient in the intensive care unit.
The patient is on a mechanical ventilator and has multiple chest tubes. The radiographer notices
that the automatic exposure control (AEC) chambers are not positioned correctly due to the
patient's supine position and the presence of tubes. Which of the following actions is most
appropriate to ensure optimal image quality while minimizing patient dose?
A. Increase the mAs by 50% and disable the AEC to manually set exposure.
B. Select the center AEC chamber and increase the kVp by 15% to compensate for the increased tissue
thickness.
C. Use the AEC with the left and right chambers selected and manually adjust the density setting to +2.
D. Disable the AEC and use a technique chart based on the patient's body habitus, ensuring the exposure index
falls within the acceptable range.
Answer: D
Rationale: Disabling AEC and using a technique chart is appropriate when AEC chambers cannot be
positioned correctly, as it ensures consistent exposure and avoids overexposure. Option A increases mAs
without addressing the chamber issue, potentially increasing dose. Option B is incorrect because
increasing kVp with AEC may not correct chamber misalignment. Option C may still result in incorrect
exposure due to improper chamber placement.
2. A radiologist is evaluating a digital radiograph of the knee obtained with a computed
radiography (CR) system. The image demonstrates quantum mottle, but the exposure index is
within the manufacturer's recommended range. Which of the following is the most likely cause of
the quantum mottle?
A. Use of a grid with a grid ratio that is too high for the CR system.
B. Insufficient mAs despite a normal exposure index due to incorrect calibration of the reader.
C. Excessive kVp causing increased scatter radiation reaching the detector.
D. Patient motion during the exposure, resulting in blur and reduced signal.
Answer: B
Rationale: Quantum mottle is caused by insufficient x-ray photons reaching the detector. A normal
exposure index may be misleading if the CR reader is calibrated incorrectly, as it could indicate a
higher exposure than actually occurred. Option A (high grid ratio) reduces scatter but also reduces
primary beam, which could cause mottle, but the exposure index would likely be low. Option C
(excessive kVp) increases scatter but also increases detector signal, reducing mottle. Option D (motion)
causes blur, not mottle.
Page 1
,3. During a fluoroscopic procedure, the radiographer notices that the automatic brightness control
(ABC) is causing the kVp to increase to 120 kVp and the mA to decrease to 0.5 mA for a patient
with a large body habitus. The image quality is suboptimal due to excessive noise. Which of the
following adjustments should the radiographer make to improve image quality while maintaining
patient dose as low as reasonably achievable (ALARA)?
A. Increase the mA manually to 2 mA and allow the ABC to adjust kVp accordingly.
B. Select a lower kVp (e.g., 80 kVp) and increase the mA to maintain a constant exposure rate.
C. Use the pulsed fluoroscopy mode at 15 pulses per second instead of continuous mode.
D. Increase the source-to-image distance (SID) to reduce patient dose and improve image quality.
Answer: B
Rationale: Selecting a lower kVp and increasing mA reduces noise because mA directly affects the
number of photons. This approach maintains exposure rate and improves image quality, though it may
increase patient dose if not carefully balanced. Option A (increasing mA alone) may cause the ABC to
lower kVp further, but the ABC's response is unpredictable. Option C (pulsed mode) reduces dose but
may not improve noise. Option D (increasing SID) reduces dose but also reduces image intensity,
potentially requiring higher technique.
4. A radiographer is performing a CT examination of the abdomen and pelvis with intravenous
contrast. The patient has a history of mild allergic reaction to iodinated contrast media (urticaria).
According to current guidelines, which of the following premedication regimens is most
appropriate for this patient?
A. Prednisone 50 mg orally 13 hours, 7 hours, and 1 hour before contrast administration, plus diphenhydramine
50 mg orally 1 hour before.
B. Methylprednisolone 40 mg orally 12 hours and 2 hours before contrast, plus diphenhydramine 50 mg
intravenously immediately prior.
C. Hydrocortisone 200 mg intravenously 4 hours and 1 hour before contrast, plus famotidine 20 mg
intravenously 1 hour before.
D. No premedication is necessary; administer nonionic low-osmolar contrast and monitor closely.
Answer: A
Rationale: The recommended premedication for a patient with a prior mild allergic reaction includes a
three-dose regimen of corticosteroids (e.g., prednisone 50 mg orally at 13, 7, and 1 hour before) and
diphenhydramine 50 mg orally 1 hour before. Option B uses methylprednisolone but the timing is
nonstandard. Option C uses intravenous hydrocortisone and H2 blocker, which is not first-line. Option
D is incorrect because premedication is indicated for prior reactions.
5. A radiographer is positioning a patient for a lateral projection of the lumbar spine. The patient
has scoliosis with a convexity to the right. The radiographer aligns the central ray perpendicular to
the image receptor and directs it to the iliac crest. Which of the following modifications should be
made to improve visualization of the intervertebral foramina?
A. Angle the central ray 15 degrees caudad and direct it to the level of L3.
B. Angle the central ray 15 degrees cephalad and direct it to the level of L4.
C. Increase the SID to 72 inches and use a grid with a higher ratio.
D. Position the patient with the left side down and use a 20-degree wedge filter.
Page 2
,Answer: B
Rationale: In scoliosis, the spine is rotated; to open the intervertebral foramina on the side of convexity
(right), the central ray should be angled cephalad to align with the foramina. Option B (15 degrees
cephalad at L4) is appropriate for the lumbar spine. Option A (caudad) would close the foramina.
Option C (increased SID) improves detail but does not address foramina visualization. Option D (wedge
filter) may help with density but not foramina opening.
6. A radiographer is performing a barium enema study on a patient with suspected diverticulitis.
During the procedure, the radiographer observes extravasation of contrast medium outside the
colonic lumen. Which of the following is the most appropriate immediate action?
A. Continue the study to document the extent of extravasation and notify the radiologist.
B. Stop the procedure immediately, monitor the patient's vital signs, and notify the radiologist and referring
physician.
C. Reduce the flow rate of barium and switch to a water-soluble contrast medium to decrease risk of peritonitis.
D. Administer intravenous glucagon to reduce colonic spasm and prevent further extravasation.
Answer: B
Rationale: Extravasation of contrast indicates a perforation, which is a medical emergency. The
procedure must be stopped immediately to prevent further leakage. The patient should be monitored for
signs of peritonitis and the physician notified. Option A is dangerous as continuing may worsen the
condition. Option C is inappropriate because any contrast extravasation is harmful. Option D does not
address the perforation.
7. A radiographer is evaluating a digital mammogram and notices a cluster of microcalcifications
in the upper outer quadrant of the left breast. The microcalcifications are pleomorphic and linear,
with some branching. According to the BI-RADS lexicon, which of the following is the most
appropriate assessment category?
A. BI-RADS 3: Probably benign.
B. BI-RADS 4C: High suspicion for malignancy.
C. BI-RADS 5: Highly suggestive of malignancy.
D. BI-RADS 0: Incomplete, need additional imaging evaluation.
Answer: B
Rationale: Pleomorphic, linear, and branching microcalcifications are characteristic of ductal carcinoma
in situ (DCIS) and are considered highly suspicious. BI-RADS 4C is used for findings with a high
suspicion of malignancy (50-95% likelihood). BI-RADS 5 is reserved for findings with 95% likelihood,
typically including spiculated masses. Option A (BI-RADS 3) is for probably benign findings with <2%
malignancy risk. Option D (BI-RADS 0) is for incomplete studies needing additional views.
8. A radiographer is performing a nuclear medicine bone scan on a patient with prostate cancer.
The patient has a serum creatinine level of 2.5 mg/dL. Which of the following modifications to the
imaging protocol is most appropriate?
A. Administer the standard dose of Tc-99m MDP and encourage increased fluid intake.
B. Reduce the administered activity of Tc-99m MDP by 50% and extend the imaging time.
C. Use Tc-99m HDP instead of MDP because of its faster renal clearance.
Page 3
, D. Delay the study until renal function improves, as the radiopharmaceutical is contraindicated.
Answer: A
Rationale: A serum creatinine of 2.5 mg/dL indicates moderate renal impairment, but Tc-99m MDP is
still safe. The standard dose can be given with increased hydration to promote clearance. Option B
(reducing activity) may degrade image quality. Option C (HDP) has similar renal clearance and does
not offer advantage. Option D (delaying) is unnecessary as the study can be performed with appropriate
hydration.
9. A radiographer is reviewing a chest radiograph and notes a right-sided pneumothorax with the
lung edge visible at the level of the lateral third rib. The patient is asymptomatic. According to the
British Thoracic Society guidelines, which of the following is the most appropriate management?
A. Immediate needle decompression followed by chest tube insertion.
B. Observation and repeat chest radiograph in 4-6 hours.
C. Administer high-flow oxygen and perform CT scan for further evaluation.
D. Perform thoracentesis to remove the air and re-expand the lung.
Answer: B
Rationale: A small pneumothorax in an asymptomatic patient can be managed conservatively with
observation. The lung edge at the lateral third rib indicates a small pneumothorax. Option A is for
tension pneumothorax or large symptomatic pneumothorax. Option C (high-flow oxygen) may be used to
accelerate resorption but is not first-line. Option D (thoracentesis) is not indicated for pneumothorax.
10. A radiographer is performing a quality control test on a digital radiography system. The test
involves exposing a uniform phantom and measuring the mean pixel value and standard deviation.
The resulting signal-to-noise ratio (SNR) is 50. If the exposure is doubled, what will be the new
SNR?
A. 25
B. 35
C. 71
D. 100
Answer: C
Rationale: SNR is proportional to the square root of the number of photons, which is proportional to
exposure. Doubling exposure increases SNR by a factor of sqrt(2) 1.414. Thus, new SNR = 50 * 1.414
70.7, rounding to 71. Option A (25) is half, which would occur if SNR decreased. Option B (35) is
incorrect. Option D (100) would require a 4-fold increase in exposure.
11. A radiograph of the abdomen demonstrates a ground-glass appearance with loss of psoas
margins and indistinct liver and splenic contours. A small amount of free intraperitoneal air is
noted under the right hemidiaphragm. Which of the following best explains the combination of
findings?
A. Ruptured hollow viscus with massive intraperitoneal fluid
B. Perforated gastric ulcer with pneumoperitoneum and ascites
C. Superior mesenteric artery syndrome with gastric dilatation
D. Pancreatitis with retroperitoneal air tracking into the peritoneum
Page 4
