ST:5 Flashcards
A [99mTc]oxidronate image of the region shown (ANTERIOR THORAX/PROXIMAL UPPER EXTREMITIES) would demonstrate all of the following structures EXCEPT the:
(a)costochondral junctions
(b) acromion processes
(c) clavicles
(d) sternum
(e) humerus
(b) The diagram depicts an anterior view for the rib cage and proximal upper extremities. The acromion processes would be demonstrated on a posterior view of the upper thorax that includes the scapulae.
For a patient undergoing bone imaging, which of the following information from the medical history is relevant to the interpretation of the bone image?
(a)splenectomy 5 years ago
(b) abdominal surgery 10 days ago
(c) radiation therapy to the breast 6 months ago
(d) gallbladder surgery a year ago
(e) results of previous bone imaging procedures
(e) Results of previous bone imaging procedures performed with nuclear medicine or another imaging modality may provide additional information not demonstrated on the current image or indications that the condition has improved or worsened. Healing soft tissue, such as that resulting from recent abdominal surgery, will concentrate bone tracer in an unexpected area. External beam radiation therapy can cause photopenic areas-areas of decreased tracer activity- on the bone image in the area where the therapy was delivered. All of this information will help the physician explain the findings on a bone image.
If a patient is injected with [99mTc]MAA while in an upright position, which of the following is most likely to be seen on the perfusion lung images?
(a)increased tracer activity in the lung apices
(b) decreased tracer activity in the lung bases
(c) decreased tracer activity in the lung apices
(d) decreased tracer activity throughout both lungs
(e) the heart
(c) If the patient is in the upright position, the apices of the lung receive very little blood flow, Consequently, more MAA particles will be distributed in the bases of the lungs than in the apices. In the supine position, although there is a blood flow gradient from anterior to posterior, there is a more homogeneous distribution of particles from apex to base.
If the usual adult dosage of [99mTc]MAA is 4 mCi, a patient who has had a right pneumonectomy should receive what dosage?
(a)1 mCi
(b) 3 mCi
(c) 2 mCi
(d) 5 mCi
(e) 4 mCi
(c) For an adult patient who has only one lung and, therefore, half the lung vasculature, half the usual dosage is recommended. This reduces the number of particles to approximately half of what is administered in a full dosage.
Which one of the following steps would be appropriate during a standby-assist wheelchair transfer?
(a)The wheelchair should be perpendicular to the imaging table.
(b) The wheelchair footrests should be out of the way.
(c) The wheelchair should be placed parallel to the imaging table.
(d) The wheelchair should be unlocked.
(e) The transfer should take place in the presence of a physician.
(b) The footrests should always be moved out of the way. The wheelchair must be properly aligned to the imaging table (depending on patient condition) and locked.
Patient preparation for infection imaging using tagged white blood cells includes:
(a)fasting for at least 4 hr with a blood glucose level below 120 mg/dL
(b) lab work and information concerning recent blood transfusions
(c) discontinuation of certain medications
(d) smoking cessation for at least 24 hr
(e) fasting for at least 4 hr with a blood glucose level below 200 mg/dL
(b) No special preparation is needed for a white blood cell infection imaging other than a possible interference if the patient has had a recent blood transfusion.
Thyroid imaging may be performed with which of the following collimators?
(a)flat field
(b) pinhole
(c) parallel hole
(d) pinhole or parallel hole
(e) slant hole
(d) A pinhole collimator provides an image with better resolution and offers the ability to obtain oblique views. A parallel-hole collimator used with electronic zoom can provide a magnified image with good resolution.
In performing a thyroid uptake, a technologist collects the thyroid counts 5 cm from the surface of the patient’s neck and the standard counts 20 cm from the surface of the neck phantom. What is the effect on the thyroid uptake value calculated from this data?
(a)The uptake value will be falsely increased.
(b) The uptake value will be falsely decreased.
(c) The uptake value will be accurate.
(d) The results are unpredictable.
(e) There is no effect.
(a) Recall that, as a point source is moved closer to the face of a flat-field collimator, more counts are collected. If the standard represents the total amount of activity administered to the patient, the counts collected from the patient’s neck represent a portion of the total amount of activity that concentrated in the thyroid gland. It is important, therefore, based on the response of the detector at a given distance, to count both the standard and the patient at the same distance. For example, suppose the standard and the patient were both counted at 20 cm, and 20,000 net cpm and 5,000 net cpm were obtained, respectively. The patient’s uptake is:
neck counts x 100 / standard counts = 5000 cpm x 100 / 20,000 cpm = 25%
If the patient were counted at 5 cm instead of 20 cm, more counts would be collected (i.e., 10,000 cpm). Then, the patient’s uptake is falsely increased:
neck counts x 100 / standard counts = 10000 cpm x 100 / 20,000 cpm = 50%
The percentage left ventricular ejection fraction calculated from the net counts per minute shown here: End diastole: 2875 End systole: 2162 is approximately: (a)25%
(b) 13%
(c) 33%
(d) 100%
(e) 75%
(a) The counts per minute are obtained from the regions of interest drawn around the end-diastolic and end-systolic images. The counts in each region are then corrected for background. The formula for calculating the left ventricular ejection fraction is:
LVEF = (net end-diastolic counts - net end-systolic counts) x 100 / net end-diastolic counts
= (2875 cpm - 2162 cpm) x 100 / 2875 cpm = 25%
When a technologist cares for a patient who is not known to have a communicable disease, all of the following infection control measures should be implemented EXCEPT:
(a)wearing gloves when collecting a blood sample
(b) decontaminating imaging equipment with an antiseptic
(c) handwashing before and after the nuclear medicine examination
(d) using a needle recapping device
(e) maintaining aseptic technique when administering the radiopharmaceutical
(b) Standard precautions should be used routinely with all patients. These precautions include activities such as hand washing, wearing gloves, and recapping needles using a safety device. Decontaminating imaging equipment would be performed only if it came in contact with biological fluids from a patient or with a patient known to be infected with a communicable disease.
Normal sinus rhythm is characterized by which of the following? I. 60-100 beats/min II. R wave occurs at constant intervals III. PR interval 0.12-0.20 sec long (a)I and II only
(b) I and III only
(c) II and III only
(d) I, II, and III
(e) III only
(d) the characteristics of normal sinus rhythm as they appear on an ECG tracing are: (1) heart rate of 60-100 beats per minute, (2) R waves at regular intervals (variance of less than 0.12 sec), (3) P waves present and precede QRS complex, (4) PR interval between 0.12 and 0.20 sec long, and (5) QRS complex less than 0.12 sec.
After stress myocardial imaging with [201Tl]thallous chloride, 1-1.5 mCi of [201Tl]thallous chloride may be administered before rest myocardial imaging to:
(a)improve patient throughput
(b) demonstrate reversible ischemia more readily
(c) demonstrate infarct size more precisely
(d) minimize visualization of attenuation artifacts
(e) maximize visualization of attenuation artifacts
(b) Defects visualized on stress images are interpreted as myocardial ischemia if the defects fill in on the resting images. However, the rate of redistribution varies, and ischemic areas may not appear to have re-perfused by 4 hr. Administering a second, smaller dose of 201Tl before rest imaging provides additional tracer in the circulation that can be extracted into there areas, improving the image quality and identifying reversible ischemia.
If the gallbladder is not visualized within 60 min during hepatobiliary imaging, which of the following may be administered?
(a)cimetidine
(b) morphine
(c) dobutamine
(d) furosemide
(e) adenosine
(b) If the gallbladder is not visualized after 1 hr but tracer is seen in the common bile duct and small intestine, morphine may be administered. Morphine acts on the sphincter of Oddi, causing it to contract, thus increasing pressure in the common bile duct and causing tracer to flow into the gallbladder.
Preparation of the patient for Meckel’s diverticulum localization includes:
(a)administration of laxatives
(b) oral or intravenous hydration
(c) an enema immediately before imaging
(d) fasting for at least 2 hr before imaging.
(e) an enema immediately after imaging
(d) Bowel preparations are contraindicated before Meckel’s diverticulum imaging because they irritate the intestinal mucosa, possibly causing a false-positive finding. It is recommended that patients fast for at least 2 hr before imaging to reduce stomach secretions that cause migration of [99mTc]pertechnetate from the stomach into the bowel.
Which of the following 99mTc-labeled agents is the preferred tracer for demonstrating intermittent gastrointestinal bleeding?
(a)human serum albumin
(b) lidofenin
(c) red blood cells
(d) sulfur colloid
(e) macro aggregated albumin
(c) Because [99mTc]sulfur colloid is cleared from the blood within 10-15 min after administration, it is preferred when the patient exhibits active gastrointestinal (GI) bleeding. In cases where the GI bleeding is intermittent and unpredictable, 99mTc-labeled red blood cells are preferred, because this tracer remains in the blood pool for an extended period that permits imaging up to 24 hr.
Furosemide is sometimes administered during renal imaging to:
(a)Rule out transplant rejection.
(b) Increase blood flow to the kidneys.
(c) Enhance tracer uptake in an abnormal kidney.
(d) Rule out ureteropelvis obstruction.
(e) Decrease blood flow to the kidneys.
(d) Furosemide is a diuretic that increases the production. Activity retained in the collecting system or renal pelvis may indicate an obstruction in that area. Furosemide is used to wash out the activity with an increased production of urine. If the activity clears after the administration of furosemide, there is no obstruction.
Which of the following events is a normal response when furosemide is administered near the end of a renal function study?
(a)The peak transit time of the radiopharmaceutical is elongated.
(b) Radioactivity is taken up into the renal cortex.
(c) Mechanical blockages in the renal collecting system are cleared.
(d) The peak transit time of the radiopharmaceutical is shortened.
(e) Radioactivity is cleared from the renal pelvis into the bladder.
(e) Furosemide is a diuretic that increase the production of urine. Activity retained in the collecting system or renal pelvis may indicate an obstruction in that area. Furosemide is used to wash out the activity with an increased production of urine. If the activity clears after the administration of furosemide, there is no obstruction. Clearance of the activity is the normal response.
Early (6 hr after injection) 67Ga imaging should be performed if which of the following conditions is suspected?
(a)sarcoma
(b) osteomyelitis
(c) lymphoma
(d) bronchogenic carcinoma
(e) chrondrosarcoma
(b) 67Ga imaging can be performed form 6 hr to 3 days or longer after tracer administration. When the examination is being performed for evaluation of an inflammatory process, early imaging (6 hr after injection) is indicated.
The most effective way of controlling the spread of infectious disease in a hospital setting is for the technologist to:
(a)Wash hands both before and after patient contact.
(b) Wear gloves, mask, and hospital gown at all times.
(c) Stay home when ill.
(d) Maintain distance from each patient.
(e) Always wear a face mask.
(a) It is widely accepted that hand washing is considered to be the single most-effective way of preventing the spread of infection in a medical care facility.
[111In]Pentetreotide normally localizes in all of the following sites EXCEPT:
(a)pituitary gland
(b) salivary glands
(c) spleen
(d) thyroid gland
(e) liver
(b) [111In]pentetreotide normally localizes in the pituitary gland, thyroid gland, liver, spleen, bladder, and bowel.
SPECT brain imaging may begin how soon after the administration of [99mTc]exametazime?
(a)immediately
(b) 1-2 hr
(c) 15-20 min
(d) 24 hr
(e) 48 hr
(b) For the best image quality, brain imaging with [99mTc]exametazime should begin no sooner than 90 min after the administration of the tracer.
Radioactivity is visualized in all of the following areas during a normal cisternographic study EXCEPT the:
(a)cerebral convexities
(b) basal cisterns
(c) central canal
(d) lateral ventricles
(e) subarachnoid space
(d) Normally, cerebral spinal fluid flows out of the lateral ventricles. Reversal of this flow (or reflux) and visualization of tracer in the lateral ventricles is an abnormal finding.
Patient preparation for instilling colloidal [32P]chromic phosphate into the peritoneal cavity includes which of the following?
(a)surgical placement of a LeVeen shunt to remove excess peritoneal fluid
(b) fasting for 8-12 hr before radiopharmaceutical administration
(c) instructing the patient about isolation requirements
(d) introducing [99mTc]sulfur colloid into the cavity to confirm that the 32P will disperse evenly
(e) administering an antacid 2-4 hours before the procedure
(d) Before instilling 32P into the peritoneal space, [99mTc]sulfur colloid is introduced to demonstrate that the agent will disperse throughout the cavity, thereby uniformly irradiating the peritoneal space.
Patient preparation for post-thyroidectomy 131I whole-body imaging for metastases may include all of the following EXCEPT:
(a)administration of 600-1000 mg of potassium perchlorate 2 hr before imaging
(b) administration of exogenous TSH
(c) discontinuation of replacement thyroid hormone
(d) following a low-iodine diet for 1-2 weeks before imaging
(e) no IV CT contrast 6 weeks before
(a) After a thyroidectomy, the purpose of 131I whole-body imaging is to detect the presence of residual thyroid tissue and/or distant metastases. To enhance the visualization of any metastases, the patient may be instructed to limit dietary iodine. The patient may also discontinue replacement thyroid hormone therapy to permit the metastases to function as thyroid tissue. Exogenous TSH may also be prescribed to stimulate the metastases to concentrate iodine.