ST:8

Question 1

Caffeine is contraindicated for which of the following interventional pharmacologic agents?
(a)CCK

(b) adenosine
(c) insulin
(d) furosemide
(e) captopril

Answer 1

(b) Products that contain methylxanthine should be held at least 12 hours before administration of adenosine. Products that contain methylxanthine include caffeine, theophylline, and theobromine.

Question 2

The recommended dosage of adenosine is:
(a)140 mcg/kg/min

(b) 14 mcg/kg/min
(c) 1.4 mcg/kg/min
(d) 1,400 mcg/kg/min
(e) 14,000 mcg/kg/min

Answer 2

(a) Adenosine should be administered using an infusion pump and given at a rate of 140 ug/kg/ min over the source of 6 minutes.

Question 3

An adult patient who has been administered adenosine starts to break out in hives and suddenly passes out, what is the first thing you should do?
(a)Shake the person and shout, “Are you okay?”

(b) Call a code.
(c) Check for a pulse.
(d) Give 2 breaths.
(e) Give 30 chest compressions.

Answer 3

(a) The technologist should activate the emergency response system. The first step in this situation for the healthcare provider is to verify victim unresponsiveness. This is usually done by the “shake and shout” approach.

Question 4

The process of eluting a dry 99Mo/99mTc generator relies on:
(a)positive pressure

(b) neutral pressure
(c) negative pressure
(d) electrical conductivity
(e) magnetic resonance

Answer 4

(c) The dry column generator uses up to a 20 mL saline charge that is applied to the exterior of the generator system. An evacuated vial is placed on the collection port and draws saline from the saline charge over the column through negative pressure to produce the yield product.

Question 5

If the results of a 99Mo/99mTc generator Moly breakthrough test are 1.2 Ci of 99mTc and 25 uCi of 99Mo, what is the approximate ratio of 99Mo to 99mTc for a Moly breakthrough determination?
(a)0.02

(b) 48
(c) 20.8
(d) 0.048
(e) 50

Answer 5

(a) Mo/Tc =
25 uCi 99Mo/ mCi 99mTc
0.025 uCi 99Mo / 1.2 Ci 99mTc = 0.02

Question 6

The USP has set the aluminum breakthrough for a 99Mo/99mTc generator at or below what amount?
(a)10 ug/mL

(b) 100 ug/mL
(c) 10 ug/ul
(d) 100 ug/uL
(e) 0.15 ug/uL

Answer 6

(a) The U.S. Pharmacopeia has set the concentration limit for Al3+ to be no greater than 10 ug/mL of the eluate.

Question 7

What is the approximate dose range for a 99mTc sulfur colloid gastric emptying study?
(a)1-5 mCi

(b) 1-5 uCi
(c) 2 uCi - 200 uCi
(d) 500 uCi - 1 mCi
(e) 10 - 15 mCi

Answer 7

(d) Part of the standard meal given to teh patient for the gastric emptying study is the mixture of 500 uCi to 1 mCi of Tc99m sulfur colloid with liquid egg whites.

Question 8

When performing a 3-phase bone scan, when should imaging begin?
(a)immediately upon injection

(b) 2 hours post-injection
(c) 10 minutes post-injection
(d) 24 hours post-injection
(e) There are no imaging requirements for a 3-phase bone scan.

Answer 8

(a) The radiopharmaceutical should be administered via bolus injection. Dynamic images of the blood flow are acquired immediately upon injection and continuing for at least 1 minute after.

Question 9

The color and clarity of which the following radiopharmaceuticals would be expected to be turbid and white?
(a)99mTc-MDP

(b) 99mTc-Hida
(c) 99mTc-MAA
(d) 99mTc-SC
(e) 99mTc-HMPAO

Answer 9

(c) The normal color and clarity of reconstituted 99mTc-MAA is turbid and white in appearance.

Question 10

If the bound radiochemical purity % is 92% and the hydrolyzed % is 3.2%, what amount of free 99mTc is in the product?
(a)92%

(b) 3.2%
(c) 4.8%
(d) 2.3%
(e) 8.1%

Answer 10

(c) 100% - 92% radiochemical purity - 3.2% hydrolyzed product = 4.8% free 99mTc

Question 11

A radiopharmaceutical kit has to be made up (reconstituted) at 0800. Given the following information, what approximate amount of 99mTc-TcO4 and saline would be needed to make up the kit?
99Mo/99mTc Generator Eluate: 850 mCi in 20 mL at 0600
Preservative-free Saline: 50 mL available
Package Insert Kit Preparation information: 8 mL kit with 65 mCi of 99mTc needed at reconstitution
(a)2 mL eluate and 6 mL saline

(b) 6 mL eluate and 2 mL saline
(c) 1.5 mL eluate and 6.5 mL saline
(d) 6.5 mL eluate and 1.5 mL saline
(e) 1.7 mL eluate and 6.3 mL saline

Answer 11

(a) 850 mCi 99mTc / 20 mL saline = 42.5 mCi/mL at 0600
Decay-correct for 2 hours for 99mTc
Decay factor = A = Ao x 0.5^(t/T1/2)
A = 42.5 mCi/mL x 0.5^(2hr/6hr) = 33.73 mCi/mL at 0800
65 mCi 99mTc needed at 0800 / 33.73 mCi/mL at 0800
= approximately 2 mL of 99mTcO4-
Total volume needed = 8 mL. Therefore, 8 mL - 2 mL = 6 mL saline needed.

Question 12

A patient dose is needed at 1300, based on the information provided below, what approximate volume would be needed for this 99mTc-based product?
RP Kit equals 150 mCi in 6 mL at 0900, dose needed at 1300 is 25 mCi
(a)2.6 mL

(b) 1.0 mL
(c) 0.63 mL
(d) 1.6 mL
(e) 0.4 mL

Answer 12

(d) 150 mCi 99mTc / 6 mL saline = 25 mCi/mL at 0900
Decay-correct for 4 hours for 99mTc
Decay factor = A = Ao x 0.5^(t/T1/2)
A = 25 mCi/mL x 0.5^(4hr/6hr) = 15.7 mCi/mL at 1300
25 mCi 99mTc needed at 1300 / 15.7 mCi/mL at 1300 = approximately 1.6 mL of 99mTc needs to be drawn.

Question 13

For a 90Y ibritumomab tiuxetan monoclonal antibody therapy, the prescribed dose is 25.6 mCi, according to NRC and CFR regulations what would be the approximate dose range for this radioimmunotherapy?
(a)20.5-30.7 mCi

(b) 23.2-28.4 mCi
(c) no more than 32 mCi
(d) no less than 15 mCi
(e) 0-32 mCi

Answer 13

(a) Therapeutic dose should not differ from +- 20% of prescribed dose.

Question 14

When using 51Cr for red blood cell labeling, what mechanism binds 80-95% of the chromate ion after 30 minutes of incubation?
(a)liver to splenic involvement traps annealed red blood cells

(b) compartmentalization of hemoglobin ion chain
(c) active transport through blood-brain barrier
(d) chromate ion is transported across red cell membrane and binds to alpha chain of hemoglobin molecule
(e) chromate ion is transported across red cell membrane and binds to beta chain of hemoglobin molecule

Answer 14

(e) When labeling RBCs with 51Cr ascorbic acid, approximately 80% to 95% of the chromate ion is promptly transported across the RBC membrane and binds to the beta chain of the hemoglobin molecule.

Question 15

To determine plasma volume using 125I human serum albumin, one technique is to collect three 10 mL heparinized blood samples at what time intervals post-injection?
(a)1, 3, and 5 minutes

(b) 5, 10, and 15 minutes
(c) 10, 20, and 30 minutes
(d) 20, 30, and 40 minutes
(e) 30, 60, and 90 minutes

Answer 15

(c) Three 10 mL heparinized blood samples are collected at exactly 10, 20, and 30 minutes after injection from a venous site other than the injection site.

Question 16

If the clinical indication for a study was evaluation of an abnormal thyroid serum laboratory result, the proper nuclear medicine procedure would be a:
(a)pancreatic scan

(b) thyroid uptake
(c) pituitary scan
(d) liver uptake with GFR determination
(e) GBEF

Answer 16

(b) Thyroid iodine uptake (24-hour iodine uptake) is a frequently requested nuclear medicine procedure to assess or confirm thyroid function particularly in patients suspected of having hyperthyroidism based on either symptoms or confirmatory laboratory test, especially suppressed TSH. Elevated levels of TSH are suggestive of hypothyroidism.

Question 17

The SNMMI Pediatric Tool Kit recommended dosage of [18F]FDG for brain imaging in pediatric patients is 0.10 mCi/kg. If a pediatric patient weighs 45 lbs, what approximate dose should the patient receive?
(a)20 mCi

(b) 2.0 mCi
(c) 4.5 mCi
(d) 45 mCi
(e) 0.20 mCi

Answer 17

(b) 45 lbs / 2.2 lbs/kg = 20.45 kg

20. 45 kg x 0.1 mCi = approximately 2.0 mCi [18F]FDG

Question 18

An adjunctive medication of furosemide is needed for a renal study. The prescribed dosage is 0.1 mg/kg as a bolus injection. If the dose is supplied as 25 mg/mL and the patient weighs 377 lbs, what approximate volume is needed for the patient dose?
(a)0.69 mL

(b) 6.8 mL
(c) 1.5 mL
(d) 0.15 mL
(e) 4.2 mL

Answer 18

(a) 377 lbs / 2.2 lbs/kg = 171.36 kg
171. 36 kg x 0.1 mg/kg = 17.136 mg needed
17. 136 mg needed / 25 mg/mL = 0.69 mL needed

Question 19

What is a radiopharmaceuticals that can be used for a brain perfusion study?
(a)[111In]WBCs

(b) [99mTc]RBCs
(c) [99mTc]MAA
(d) [99mTc]sulfur colloid
(e) [99mTc]bicisate

Answer 19

(e) The two primary radiopharmaceuticals used for brain perfusion imaging are 99mTc-exametazime (HMPAO) and 99mTc-bicisate (ECD).

Question 20

Which of the following radiopharmaceuticals would be used for a bone marrow evaluation?
(a)[111In]WBCs

(b) [99mTc]RBCs
(c) [99mTc]MAA
(d) [99mTc]sulfur colloid
(e) [99mTc]bicisate

Answer 20

(d) The radiopharmaceutical used for evaluation of bone marrow is 99mTc-sulfur colloid, Filtered or unfiltered sulfur colloid can be used.

Question 21

As osteoclastic activity increases in relationship to osteoblastic activity, bone deposition:
(a)increases

(b) decreases
(c) stays constant
(d) forms new osteoclasts
(e) forms new osteoblasts

Answer 21

(b) Osteoblasts are associated with bone growth, and osteoclasts are associated with absorption and removal of bone. Bone has a constant cycle of absorption and growth.

Question 22

Hydroxyapatite salts of the bone consist of:
(a)stannous pyrophosphate

(b) calcium, strontium, phosphorus
(c) phosphorus and hydroxide
(d) calcium phosphate and calcium carbonate
(e) phosphoric calcium and methyl hydroxide

Answer 22

(d) The bone salt material (inorganic matter) has the crystalline form of an apatite and is composed of the following ions: calcium, phosphate, hydroxyl, carbonate, and citrate.

Question 23

A 49-year-old female patient receives 25 mCi of 99mTc-MDP for a bone scan. The organ receiving the greatest radiation dose from this injection is:
(a)bones

(b) kidneys
(c) bone marrow
(d) bladder
(e) liver

Answer 23

(d) The bladder wall receives the most radiation dose with the bladder wall - approximately 2.6 rads / 20 mCi at 2 hours.

Question 24

Bone cancers, bone metastases, and other bone disorders produce extremely high levels of _____ in the blood.
(a)lactic dehydrogenase

(b) alkaline phosphatase
(c) amylase
(d) creatinine kinase
(e) calcium

Answer 24

(b) Patients with osseous metastasis may present with elevated alkaline phosphatase with approximately 77% occurrence.

Question 25

Normal renal function can be indicated on a bone scan by: (a)equal kidney activity that is less than bone activity (b) equal kidney activity that is significantly more intense than bone activity (c) absence of kidney activity (d) absence of bladder activity (e) absence of kidney and bladder activity

Answer 25

(a) 99mTc-MDP or 99mTc-HMDP are excreted via the urinary system and visualization of the kidneys is common. This activity is variable but is usually less than the surrounding bone activity. Kidney diseases is associated with pronounced asymmetry of renal activity.

Question 26

Visible rib lesions that are arranged in a linear fashion are generally indicative of: (a)rib metastases (b) rib trauma (c) inflammation of the lungs (d) contamination (e) lung infiltrates

Answer 26

(b) Rib fractures almost always show intense activity and can often be recognized by their location in consecutive ribs.

Question 27

Which of the following is the device used to convert scintillation light into an electric signal in a CT scanner? (a)photomultiplier tube (b) analog to digital converter (c) Xenon chamber (d) photodiode (e) cathode

Answer 27

(d) Scintillation detectors use solid-state photodiodes to play the role of the photomultiplier tube (PMT) in Gamma Cameras. Photodiodes absorb the scintillations given off by the crystal and, in response, they emit an electric signal.

Question 28

A bone scan of a 60-year-old female demonstrates a diffuse pattern of intensely increased activity in the skull, proximal femurs, and one side of the pelvis. This appearance is typical of what disease process? (a)Ewing's sarcoma (b) multiple myeloma (c) Legg-Perthe's disease (d) renal failure (e) Paget's disease

Answer 28

(e) Paget's disease is characterized by marked increase in skeletal uptake. Most-common areas are pelvis, spine, skull, femur, scapula, tibia, and humerus.

Question 29

What portion of the ECG wave represents the depolarization of the ventricles? (a)P-wave (b) T-wave (c) U-wave (d) QRS complex (e) ST segment

Answer 29

(d) The QRS complex indicates depolarization of the ventricles.

Question 30

Dipyridamole is supplied to a nuclear medicine department in 10 mL vials, each containing 50 mg. If a patient weighs 155 pounds, how many mL must be injected for the patient to receive 0.56 mg/kg (a)7.9 mL (b) 8.7 mL (c) 17.4 mL (d) 39.5 mL (e) 5.3 mL

Answer 30

(a) 155 lbs / 2.2 lbs/kg = 70.45 kg 70.45 kg x 0.56 mg/kg = 39.45 mg needed 50 mg / 10 mL = 5 mg/mL 39.45 mg needed / 5 mg/mL = approximately 7.9 mL needed

Question 31

A patient has an enlarged left atrium. When drawing an ROI for calculation of LVEF after radionuclide ventriulography, the technologist includes some activity from the left atrium. The resulting ejection fraction would: (a)be unchanged (b) be falsely elevated (c) be falsely lowered (d) show akinesias (e) show paradoxical wall motion

Answer 31

(c) Non-superimposed but adjacent extracardiac activity may also cause a negative reconstruction artifact, resulting in an apparent reduction in activity in the adjacent myocardial segment.

Question 32

Which of the following is the most likely cause of false anterior or lateral wall defects on myocardial perfusion imaging? (a)center of rotation error (b) respiratory motion (c) too few projections (d) attenuation by breast tissue or implant (e) multiple pulmonary emboli

Answer 32

(d) The combination of prone and supine imaging is useful in distinguishing inferior wall defects from diaphragmatic attenuation, anterior wall defects from breast attenuation, and lateral wall defects from attenuation caused by excessive lateral wall fat.

Question 33

Why is it necessary to inject two doses of 99mTc-sestamibi for a myocardial perfusion study, including both stress and rest conditions? (a)The physical half-life of 99mTc is too short to obtain both image sets from one injection. (b) The effective half-life of 99mTc is too short to obtain both image sets from one injection. (c) There is not redistribution of 99mTc-sestamibi within the myocardium (d) Sestamibi is not retained by the myocardium fro a sufficient amount of time. (e) Images would be degraded on stress images after exercise.

Answer 33

(c) Like [201Tl]thallous chloride, 99mTc-sestamibi is taken up by the myocardium in proportion to blood flow. Unlike [201Tl]thallous chloride, they passively diffuse across the cell membrane, bind to mitochondria, and exhibit limited redistribution. Because of the limited redistribution, one-day protocols require a low-dose/high-dose, two-injection procedure.

Question 34

When performing a dual isotope myocardial perfusion rest/stress study, which isotope should be injected first? (a)201Tl (b) 99mTc (c) 18F (d) It does not matter which is injected first, as long as the patient is fasting. (e) 11C

Answer 34

(a) 3-4 mCi (11-148 MBq) of [201Tl]thallous chloride is administered at rest and images are obtained about 15 minutes later. About 30 minutes after the rest images are completed, the stress portion of the exam - either via treadmill or pharmacologically - is performed with 25-30 mCi of the 99mTc agent.

Question 35

Persistent pulmonary activity and poor visualization of the left side of the heart represent _____ during a first pass evaluation. (a)a ventricular aneurysm (b) a left-to-right intracardiac shunt (c) a right-to-left intracardiac shunt (d) a pulmonary embolism (e) primary pulmonary hypertension

Answer 35

(b) Persistent pulmonary activity and poor visualization of the left side of the heart represent a left-to-right intracardiac shunt during a first-pass evaluation.

Question 36

Captopril renal scans are commonly ordered to evaluate: (a)renal failure (b) renal hypotension (c) renal hypertension (d) GFR (e) ERPF

Answer 36

(c) The use of captopril has an effect on the renogram in patients with unilateral renovascular hypertension. The precaptopril renogram shows normal time course of activity in the right and left kidneys. In the post-captopril renogram, the kidney affected by renal artery stenosis is greatly diminished because of the reduced filtration pressure induced by captopril's inhibition of angiotensin II production.

Question 37

The appearance of a renal cyst on a radionuclide scan would most likely: (a)be more perfused than the surrounding kidney (b) be photopenic, compared to surrounding kidney (c) cause the surrounding kidney to take up more tracer than the other kidney (d) be about the same activity as the surrounding kidney (e) vary greatly depending on patient weight

Answer 37

(b) Masses not representing renal paraenchyma, such as neoplasms, abscess, cysts, hematoma, or infarcts, present as photopenic lesions in the renal paraenchyma.

Question 38

Which of the following is used to minimize scatter radiation from tissues beyond the relevant anatomical slice in a CT scanner? (a)bow-tie filter (b) analog to digital converter (adc) (c) grid (d) rotating target (e) collimator

Answer 38

(e) Pre-patient collimators define and shape the beam according to the procedure by physically restricting the x-ray beam to the selected slice thickness. This protects the patient from excess radiation and minimizes scatter radiation from tissues beyond the relevant anatomical slice.

Question 39

All of the following are necessary for an effective renal plasma flow camera method calculation, EXCEPT: (a)pre-injection syringe counts (b) post-injection syringe counts (c) patient height (d) patient weight (e) blood draw of at least 1 cc

Answer 39

(e) Camera-based calculations of effective renal plasma flow are not as accurate but require pre- and post-injection syringe counting, imaging, and patient height and weight. No blood draw or urine collection is required.

Question 40

Pulmonary blood flow in a person sitting in an upright position will be: (a)more abundant in the base of the lungs (b) more abundant in the apex of the lungs (c) more abundant posteriorly than anteriorly throughout the lungs (d) more abundant anteriorly than posteriorly throughout the lungs (e) uniformly distributed throughout the lungs

Answer 40

(a) In a normal, upright patient, both ventilation and perfusion increase progressively from the lung apex to the bases. This gradient is more pronounced for perfusion. This is why MAA injections are performed with the patient supine.

Question 41

In the absence of a ventilation scan, a segmental or lobar perfusion defect seen on [99mTc]MAA perfusion scintigraphy would be _____ in the diagnosis of pulmonary embolism. (a)both sensitive and specific (b) sensitive, but not specific (c) specific, but not sensitive (d) non-sensitive, and non-specific (e) uninterpretable

Answer 41

(b) Performing both ventilation and perfusion examinations on the same patient at the same time permits the physician to determine whether perfusion defects are associated with ventilation defects, which may increase the specificity of the findings.

Question 42

Prolonged retention of 133Xe in regions of the lung corresponds to: (a)obstructive lung disease (b) reduced trapping of particles in the lungs (c) pulmonary emboli (d) left-to-right shunt (e) right-to-left shunt

Answer 42

(a) COPD and emphysema present as inhomogeneous wash-in, patchy equilibrium, and areas of trapping delaying wash-out (especially lower lobes).

Question 43

The nuclear medicine technologist notices the appearance of esophagus and stomach on a DTPA aerosol ventilation scan. The most appropriate response is to: (a)Prepare a new kit of DTPA and re-administer to the patient. (b) Check the particle size of the aerosol. (c) Continue the scan; this is a typical finding. (d) Change the tubing and check the nebulizer for cracks. (e) Have the patient hold their breath during re-administration of the dose.

Answer 43

(c) A DTPA study may have activity in the esophagus and in the stomach due to swallowing.

Question 44

Which of the following would most likely result in a decreased thyroid uptake value? (a)Grave's disease (b) autoimmune thyroiditis (c) toxic nodular goiter (d) TSH secretion (e) nontoxic goiter

Answer 44

(b) One factor affecting decreased thyroid uptake is subacute or autoimmune thyroiditis.

Question 45

All of the following sites in the body are known to concentrate pertechnetate to a level greater than that of plasma, EXCEPT: (a)salivary glands (b) gastric mucosa (c) choroid plexus (d) thymus gland (e) thyroid gland

Answer 45

(d) The biodistribution of 99mTc-pertechnetate is similar to the iodide anion, with uptake in the thyroid, salivary glands, gastric mucosa, and choroid plexus.

Question 46

All of the following substances could falsely decrease the radioactive iodine uptake value, EXCEPT: (a)perchlorate (b) iodinated x-ray contrast media (c) thyroid replacement therapy (d) consumption of kelp and turnips (e) acetaminophen

Answer 46

(e) Thyroid iodine uptake is falsely low when patients have increased their dietary iodine, have taken supplements or medication containing iodine, or have recently undergone x-ray studies with iodinated contrast material.

Question 47

Patients being treated for thyroid disorders with exogenous T3 or synthroid should have those medications discontinued for at least _____ before obtaining a radioiodine uptake and scan. (a)3-5 days (b) 1 week (c) 3 weeks (d) 1-2 months (e) 6-8 months

Answer 47

(c) Patients taking triiodothyronine (Synthroid) should discontinue the medication 2-3 weeks before undergoing a thyroid uptake and scan.

Question 48

Barium studies should not precede liver imaging since barium: (a)falsely stimulates liver function (b) scatters gamma photons causing photopenia (c) will cause the tagged material to accumulate in the gallbladder (d) will cause some portions to hyperfunction giving false "hot" areas (e) cause the tagged material to reflux into the stomach

Answer 48

(b) Liver scintigraphy should not be performed after administration of any iodinated or barium-containing contrast agents. The contrast agents could cause attenuation artifacts.

Question 49

Which pathology listed below is NOT a possible cause of delayed gastric emptying? (a)scleroderma (b) hyperthyroidism (c) peptic ulceration (d) diabetes mellitus (e) vagotomy

Answer 49

(b) Causes of delayed gastric emptying are mechanical obstruction or altered function, such as diabetic gastroparesis, diabetes mellitus, surgery drugs, gastric outlet obstruction, scleroderma, chronic idiopathic intestinal pseudo-obstruction [CIIP], idiopathic gastroparesis, amyloidosis, or anorexia nervosa.

Question 50

Detection of a Meckel's diverticulum is possible with [99mTc]pertechnetate since it localizes in the: (a)salivary glands (b) gastric mucosa (c) choroid plexus (d) thyroid gland (e) red blood cells

Answer 50

(b) Meckel's diverticulum imaging is performed with 99mTc pertechnetate, which concentrates in ectopic gastric mucosa.

Question 51

Hepatic artery catheters that deliver chemotherapeutic agents directly to the site of the liver metastases can be evaluated for proper placement with the use of a: (a)bolus intravenous injection of [99mTc]pertechnetate (b) bolus intravenous injection of [99mTc]sulfur colloid (c) slow injection of the chemotherapeutic agent into the infusion port (d) slow injection of [99mTc]MAA into the infusion port (e) slow injection of [99mTc]pertechnetate into the infusion port

Answer 51

(d) With the catheter in the expected position for therapy administration, arteriovenous shunting is assessed with a 99mTc MAA scan. The 99mTc MAA is administered into the liver.

Question 52

Which of the following is considered a Quality Control test required only monthly or quarterly for a CT scanner? (a)spatial resolution (b) CT number accuracy (c) image noise (d) detector response at various kVp settings (e) detector response at various mA settings

Answer 52

(a) QC tests such as image slice thickness, spatial resolution, linearity of CT numbers, and low- and high-contrast resolution are required on a monthly or quarterly basis.

Question 53

Which of the following from an 131I therapy patient would contain the greatest amount of radioiodine? (a)saliva (b) urine (c) feces (d) sweat (e) hair

Answer 53

(b) Within 24 hours of dosage, 76% of the non-bound iodide is excreted through the kidneys. The maximum thyroid uptake is assumed to be only 15%

Question 54

The use of a nebulizer is required with which of the following radiopharmaceuticals during lung imaging? (a)[99mTc]DTPA (b) [99mTc]MAA (c) 127Xe (d) 133Xe (e) [99mTc]MAA with particles <100 microns

Answer 54

(a) 99mTc-DTPA lung imaging is done by generating an aerosol form an ultrasonic nebulizer to a positive pressure nebulizer.

Question 55

Specially shaped filters in CT scanners, like the bow-tie filters, are designed to: (a)increase the number of views per linear scan distance (b) decrease the overlapping of images during acquisition (c) produce a more-uniform x-ray beam at the detectors (d) decrease image noise by producing more x-rays (e) increase quantum mottle

Answer 55

(c) Specially shaped filters like the bow-tie filter are designed to produce a more-uniform (mono-energetic) x-ray beam at the detectors. The radiation dose to the lateral parts of the patient is decreased to be approximately equal to that in the middle of the body.

Question 56

Which radiopharmaceutical is commonly used to image cavernous hemangioma? (a)[99mTc]albumin colloid (b) [99mTc]RBCs (c) [99mTc]mebrofenin (d) [99mTc]pertechnetate (e) [99mTc]sulfur colloid

Answer 56

(b) Tagged 99mTc-RBCs is the recommended radiopharmaceutical for liver cavernous hemangioma.

Question 57

Which imaging study is acquired while an abdominal binder is inflated to increasing pressures? (a)Meckel's diverticulum study (b) gastric emptying study (c) esophageal transit study (d) esophageal reflux study (e) gastrointestinal bleeding study

Answer 57

(d) A gastroesophageal reflux study is done by acquiring 30-second images with pressures in the abdominal binder at 0, 20, 40, 60, 80, and 100 mm Hg.

Question 58

A synthetic form of cholecystokinin is: (a)glucagon (b) cimetidine (c) pentagastrin (d) sincalide (e) mebrofenin

Answer 58

(d) Sincalide is the synthetic C-terminal octapeptide of cholecystokinin (CCK).

Question 59

What is the preparation for renal functional imaging with technetium-99m-MAG3? (a)NPO for at least 4 hours before injection. (b) Patient must be well-hydrated. (c) Patient must not void for at least one hour before imaging. (d) Patient must drink nothing for two hours before the examination. (e) All patients must be catheterized.

Answer 59

(b) The patient should hydrate well and void just before the test.

Question 60

Which patient will have the longest wait before an accurate thyroid uptake with 123I can be obtained? (a)a patient who had a CTA (b) a patient who took synthroid (c) a patient who was given perchlorate (d) a patient who was given Lugol's solution (e) a patient who took kelp tablets

Answer 60

(a) A patient who has had a CTA procedure has received intravenous iodinated contrast. This patient should wait at least one month before imaging; Synthroid wait time is at least 3 weeks; Perchlorate wait time is at least 2 week; Lugol's solution wait time is at least 2 weeks; and kelp tablet wait time is at least 2 weeks.

Question 61

Which of the following is used in the treatment of Non-Hodgkin's lymphoma? (a)82Rb (b) [32P]chromic phosphate (c) 90Y ibritumomab tiuxetan (d) 153Sm microspheres (e) [131I]sodium iodide

Answer 61

(c) 90-Y-ibritumomab tiuxetan is murine IgG1 kappa monoclonal antibody directed against the CD20 antigen found on the surface of normal and malignant B cells (non-Hodgkin's lymphoma).

Question 62

Sequential acquisitions taken while the patient exhales 133Xe comprise the _____ portion of the test. (a)washout (b) wash-in (c) perfusion (d) equilibrium (e) sequestrial

Answer 62

(a) Serial images are taken at 30-60 second intervals as the xenon clears from the lungs comprising the wash-out portion of the exam.

Question 63

Which of the following statements is not a consequence of increasing kVp in a CT scanner (a)increases the number of views per linear scan distance (b) increases the energy of the x-rays (c) creates fewer beam-hardening artifacts (d) reduces attenuation differences in tissue (e) decreases noise

Answer 63

(a) Increasing kilovolt peak increases the energy of the x-rays, decreases noise, and creates fewer beam-hardening artifacts, but increases the dose to the patient and reduces attenuation differences in tissue. Decreasing the pitch increases the number of views per linear scan distance.

Question 64

The radiopharmaceutical used for assessment of CSF dynamics is administered: (a)intravenously (b) intrathecally (c) subcutaneously (d) intramuscularly (e) intradermally

Answer 64

(b) Radionuclide cisternogram is used for the diagnosis of the cause of hydrocephalus, where hydrocephalus is abnormal enlargement of the CSF spaces because of abnormal production, absorption, or circulation of CSF. The tracer is injected into the subarachnoid space of the lumbar spine, and the head is imaged at 3 and 24 hours after injection. An intrathecal injection is defined as medications such as contrast media or radiopharmaceuticals that are administered using a spinal needle to inject medications directly into the subarachnoid space of the spinal cord.

Question 65

What is the average CT number for bone in Hounsfield Units (HU)? (a)+2,000 (b) +500 (c) +100 (d) +50 (e) +20

Answer 65

(b) The average CT number value for bone is about +500 HU. This value may vary with the beam quality of the CT scanner.

Question 66

The exposure limit for the developing fetus of a declared pregnant worker is: (a)0.1 mRem (b) 1 mRem (c) 1 Rem (d) 0.5 Rem (e) 5 Rem

Answer 66

(d) The exposure limit for the developing fetus of a declared pregnant worker is 0.5 rem.

Question 67

The medium that interacts with radiation (sensitive volume) in a pocket dosimeter is: (a)NaI (b) LiF (c) Al2O3 (d) gas (e) liquid

Answer 67

(d) Pocket dosimeters are ionization chambers. Ionization chamber instruments are operated in the ionization region of the gas amplification curve and are filled with gas.

Question 68

Which of the following statements is not a consequence of increasing mA in a CT scanner? (a)decreases image noise (b) increase the energy of the x-rays (c) increase radiation dose to patient (d) produces more x-rays (e) increases contrast resolution

Answer 68

(b) Increasing mA decreases image noise by producing more x-rays and increases contrast resolution, but increases radiation dose to the patient. Increasing kVp increases the penetration of the object being x-rayed by increasing the energy of the x-rays.

Question 69

If the radiation intensity was "x" at a distance "d" from a source, what would the radiation intensity be at half of that distance? (a)2X (b) X^2 (c) 4X (d) X^4 (e) X/2

Answer 69

(c) The inverse square law results in the radiation intensity quadrupling if the distance from the source is halved, or the radiation intensity decreasing to one-fourth of its value if the distance is doubled.

Question 70

The dose response in humans at around 2 Sv is: (a)permanent hair loss (b) permanent sterility (c) GI syndromes (d) CNS syndrome (e) radiation sickness

Answer 70

(e) At a minimum whole-body dose of 2 Sv (200 Rem), radiation sickness will be observed.

Question 71

The largest background source of radiation to the general public in the United States is: (a)radon and thoron (b) computed tomography (c) nuclear cardiology (d) air travel (e) commercial nuclear power

Answer 71

(a) Radon and thoron comprise the largest source of background radiation to the general public in the United States (37%).

Question 72

Committed dose equivalent is used to represent: (a)external irradiation (b) internal irradiation (c) lens irradiation (d) extremity irradiation (e) medical irradiation for therapy

Answer 72

(b) Because internally deposited radionuclides may deliver doses to tissues or organs of the body over a period of time, the concept of committed dose has been defined. Committed dose equivalent (CDE) is simply the committed dose equivalent to the organ or tissue over the irradiated time.

Question 73

Where is the Data Acquisition System (DAS) in a CT scanner? (a)under the patient imaging table (b) inside the operator's console (c) inside the gantry (d) inside the electronics cabinet (e) inside the computer workstation

Answer 73

(c) The gantry houses the key components of the scanner: the x-ray tube, detector array, power generator, and data acquisition system.

Question 74

All of the following organs are very sensitive to radiation-induced carcinogenesis EXCEPT: (a)active bone marrow (b) thymus gland (c) thyroid gland (d) female breast (e) lungs

Answer 74

(b) The organs that are most sensitive to radiation-induced carcinogenesis are the active bone marrow, thyroid, female breasts, and lungs.

Question 75

Chances of congenital abnormalities are high if the fetal irradiation is during which gestational age? (a)pre-implantation (b) first trimester (c) second trimester (d) third trimester (e) post-partum

Answer 75

(b) Irradiation during organogenesis is the period of most concern. For this reason, it is often noted that radiation should be particularly limited during the first trimester.

Question 76

According to NRC, a restricted area is one in which a person would receive a radiation dose of more than: (a)2 mRem in 1 hr (b) 5 mRem in 1 hr (c) 10 mRem in 1 hr (d) 20 mRem in 1 hr (e) 50 mRem in 1 hr

Answer 76

(a) According to the NRC, a restricted area is one in which a person would receive a radiation dose of more than 2 mRem in 1 hour.

Question 77

All of the following are examples of radioactive caution signs, EXCEPT: (a)"Caution: Radioactive Material" (b) "Caution: Extreme Level Radiation Area" (c) "Grave Danger: Very High Radiation Area" (d) "Caution: Radiation Area" (e) "Caution: High Radiation Area"

Answer 77

(b) "Caution: Radioactive Material," "Caution: Radiation Area," "Grave Danger: Very High Radiation Area," and "Caution: High Radiation Area" are all examples of radioactive signs.

Question 78

What type of QC is performed daily in PET to provide accurate transmission scan data for the attenuation correction of images? (a)coincidence timing calibration (b) energy window calibration (c) normalization calibration (d) blank scan (e) absolute activity calibration

Answer 78

(d) Blank scans are performed daily to provide accurate transmission scan data for the attenuation correction of images.

Question 79

If radiation levels of a hotlab has been measured to be 6 mRem/hr, which of the following signs should be posted on the door? (a)No posting is required. (b) "Caution: Radioactive Materials" (c) "Caution: Radiation Area" (d) "Caution: High Radiation Area" (e) "Caution: Very High Radiation Area"

Answer 79

(c) Radiation area means an area that is accessible to individuals in which radiation levels could result in an individual receiving a dose equivalent in excess of 5 mRem in 1 hour at 30 cm from the radiation source or from any surface that the radiation penetrates.

Question 80

131I imaging is best done with which type of collimator? (a)medium energy (b) low energy (c) high specificity (d) high energy (e) No collimator should be used.

Answer 80

(d) 131I is best imaged with a high-energy collimator.

Question 81

The mechanism of decay for nuclides that have too many protons relative to the number of neutrons is: (a)beta minus decay (b) beta plus decay (c) gamma ray emission (d) internal conversion (e) electron capture

Answer 81

(e) Electron capture is a mechanism of decay for nuclides that have too many protons relative to the number of neutrons.

Question 82

Full width at half maximum (FWHM) is often used as a measure of: (a)uniformity (b) sensitivity (c) intensity (d) resolution (e) dead time

Answer 82

(d) Full width at half maximum is often used as a measure of resolution.

Question 83

Uncorrected flood field non-uniformities cause _____ artifacts in tomographic reconstruction. (a)irregular (b) dropout (c) ring (d) undulating (e) linear

Answer 83

(c) Because SPECT imaging requires a rotating gamma camera, any abnormalities inherent to the detector or the rotational mechanics will be carried through every projection, leading to a ring artifact. Abnormalities that will be seen as ring artifacts include flood non-uniformities and collimator defects.

Question 84

What system contains information about patients, doctors, and insurance coverage within the hospital? (a)Hospital Information System (b) Hospital Inpatient System (c) Radiology Information System (d) Picture Archival System (e) Radiology Patient Portal

Answer 84

(a) In the hospital, the radiology information system (RIS), which holds details about radiology exams, may be networked to the hospital information system (HIS), which contains information about patients, doctors, insurance coverage, and so on.

Question 85

As the sample volume is increased, well counter counting efficiencies are: (a)reduced (b) improved (c) unchanged (d) increased to a point, then reduced (e) unpredictable

Answer 85

(a) As the sample volume is increased, well counter counting efficiencies are reduced. This is due to geometric efficiency. The configuration with the largest geometric efficiency occurs when the detector surrounds the source completely.

Question 86

According to national standards, how often should the activity linearity of a dose calibrator be measured? (a)each day of use (b) weekly (c) monthly (d) quarterly (e) annually

Answer 86

(d) Dose calibrator activity linearity should be measured quarterly.

Question 87

According to the NRC, G-M counter calibration must be done how often? (a)each day of use (b) weekly (c) monthly (d) quarterly (e) annually

Answer 87

(e) Geiger-Muller survey meters should be calibrated annually.

Question 88

According to the NRC, records of surveys must be retained for how long? (a)1 year (b) 3 years (c) 5 years (d) 10 years (e) indefinitely

Answer 88

(b) Records of surveys must be retained for 3 years.

Question 89

When a technologist is measuring the activity of a long-lived radioactive source daily in a dose calibrator, which of the following quality control tests is the technologist assessing? (a)accuracy (b) constancy (c) geometry (d) linearity (e) sensitivity

Answer 89

(b) The essential daily quality control test of a dose calibrator is a constancy reading of the activity of a long-lived source (usually Cs-137, although some users employ two or three radionuclides of varying energies).

Question 90

For a parallel-hole collimator, the best resolution is at: (a)the collimator surface (b) 10 cm (c) 15 cm (d) 20 cm (e) the focal distance

Answer 90

(a) Parallel-hole collimator resolution degrades the test images as the distance between the collimator and the object increases.

Question 91

How often should the COR check be performed? (a)each day that SPECT scans will be performed (b) at least weekly (c) biweekly (d) at least monthly (e) every 6 months

Answer 91

(b) The current standard of practice is to check the COR weekly, at least until the system can be shown to be stable over a period of at least several months.

Question 92

If a technologist wishes to evaluate the intrinsic uniformity of a camera used for planar imaging and is preparing a dose of technetium-99m, how much activity is sufficient for the image? (a)10 mCi (b) 1 mCi (c) 200 uCi (d) 2 mCi (e) 20 mCi

Answer 92

(c) For an intrinsic flood, the collimator is removed and a point source containing a small (<1 mCi or 37 MBq) amount of radioactivity is placed at a distance of at least 5 times the largest camera dimension from the camera face.

Question 93

To obtain high resolution images of a small organ, gland, or join which collimator would be most useful? (a)diverging (b) flat field (c) high-energy diverging (d) low-energy parallel hole (e) pinhole

Answer 93

(e) The pinhole collimator is a large, hollow lead cone with a single small hole or aperture at the point of the cone. It is used to magnify very small organs, such as the thyroid gland.

Question 94

If a 15% window is set around a centerline of 364 keV, what energies will be accepted by the pulse high analyzer? (a)309-419 keV (b) 328-400 keV (c) 337-391 keV (d) 346-382 keV (e) 360-368 keV

Answer 94

(c) 364 keV x 0.15 = 54.6 keV 54.6 keV / 2 = 27.3 keV Lower threshold: 364 keV - 27.3 keV = approximately 337 keV Upper threshold: 364 keV + 27.3 keV = approximately 391 keV

Question 95

When a high-activity radionuclide is used in a PET scan, what is the reason for image degradation? (a)attenuation increases (b) coincident pairs decrease (c) deadtime decreases (d) noise increases (e) random events increase

Answer 95

(e) For commonly used PET radionuclides, the average positron range varies significantly so the resolution varies with the choice of radionuclide. The possibility that the two annihilation photons are not exactly 180 degrees opposed adds uncertainty to the location of the annihilation event. This degrades resolution.

Question 96

A pair of annihilation photons striking two detectors at the same time is termed a: (a)random count (b) positron interaction (c) annihilation count (d) true count (e) scatter count

Answer 96

(d) A pair of annihilation photons striking two detectors at the same time is termed a true count or true coincidence annihilation event.

Question 97

How often should a "blank scan" be performed in PET? (a)with every patient study (b) daily (c) weekly (d) biweekly (e) monthly

Answer 97

(b) Blank scans are performed daily to provide accurate transmission scan data for the attenuation correction of images.

Question 98

How often should a tomographic uniformity evaluation be performed in a CT scanner? (a)with every patient study (b) daily (c) monthly (d) quarterly (e) annually

Answer 98

(b) Tomographic uniformity evaluation should be performed on a CT scanner daily.

Question 99

How often should a dose index assessment be performed in a CT scanner? (a)with every patient study (b) daily (c) monthly (d) quarterly (e) annually

Answer 99

(e) A CT dose index assessment should be performed by a certified health physicist (CHP) annually.

Question 100

When a poly-energetic x-ray beam passes through an attenuating material, more low-energy x-rays are absorbed than high-energy x-rays. This effect is called: (a)acquisition factor (b) beam hardening (c) bow-tie attenuation (d) cone-beam geometry (e) quantum mottle

Answer 100

(b) As gamma rays travel through an attenuating material, more low-energy gamma rays are absorbed than high-energy gamma rays, a phenomenon called beam hardening, so the energy composition of the photon beam changes as it is attenuated.