Nucs

Front 1

How are radionuclides produced?

Back 1

REACTOR PRODUCED:
- usually contaminated with the carrier.
- used for production of Tc (Molybdenum reactor is used)

CYCLOTRON PRODUCED:
- collision of charged particles with a target nuclide.
- produces a carrier free product
- used for prodcution of 67-gallium, 123-I, 201-Th (these require large cyclotrons)
- Smaller cyclotrons can produce 18-F, Na, C for PET scanning.

FISSION PRODUCED:
- splitting of heavier nucleus into smaller nuclei.
- carrier free product
- used for production of 131-I and 99Mo.

Front 2

1. How is Mo-99/Tc-99m generator produced?
2. How is the generator made?
3. What are the contaminants of the Mo-99-Tc99m generator?

Back 2

1. Mo-99 can be produced by:
- Irradition of Mo-98 is with neutrons.
- Fission
2. Generator is made of a glass column that is filled with alumina. Mo-99 and daughter isotope Tc-99m are firmly absorbed onto the alumina. The Tc-99m can be separated from the alumina by passing NaCL through the column.
3. Alumina and Mo-99.

Front 3

1. What is the Mo-99m breakthrough test?
2. What is the NRC limit for Mo-99 contamination?
3. How is the physical evaluation done?
4. How is the chemical evaluation done?

Back 3

1. Checks for Mo-99 contamination in the eluate which results in increased radiation dose to the paitent with poor image quality.
2. 0.15 microCu Mo-99 per 1mCi Tc-99m.
3. The eluate is placed in a container with 1/4 inch lead wall which screens out the 140KeV photon from Tc-99m, but allows the 740 and 780KeV Mo-99 photons to be measured by a dose calibrator.
4. Chemical evaulation: Mo in the eluate reacts with phenylhydrazine to form colored complexes.

Front 4

1. What is the aluminum ion breakthrough?
2. What is the effect of aluminum contamation?
3. What is the NRC limit?
4. What does the chemical evaluation for aluminum entail?
5. How do you determine radiolabeling effiiciency?

Back 4

1. Remember that the Mo99-Tc-99m are absorbed on the surface of alumina. When eluted with saline, some aluminum also breaks through.
2. Results in degradation of the image quality.
3. NRC limit is 10 micrograms per mL of eluate.
4. Standard test kit (colorimeter) that has a special test paper strip containing a chemical that is sensitive to the presence of aluminum ion.
5. Determination of unbound or free Tc99m within a radiopharmaceutical preparation can be done with thin layer chromatography with acetone solvent. Regulatory standards require at least 95% radiolabeling efficiency.

Front 5

1. What are the causes of hypercalcemia?
2. What agents and dosages are used for detection of parathyroid adenomas?
3. What should be your FOV?
4. What other lesions may demonstrate uptake with sestamibi or tetrafosmin?

Back 5

1. Parathyroid adenoma (85%), parathyroid hyperplasia (10%), parathyroid carcinoma (<1%)
2.
- Single tracer study: 20mCi of Tc-99m labeled Tetrafosmin or **Sestamibi. Early (20 mins) and Delayed (2 hours) planar and SPECT images are acquired.
SUBTRACTION TECHNIQUE: used if no focus is seen on delayed images.
Dual tracer: Early Sestamibi or Tetrafosmin and I-123.
3. The FOV should include the region from the carotid bifurcation to the lower mediastinum.
4. Thyroid adenoma/carcinoma or metastatic LAD

Front 6

1. What are the different types of dementias?
2. What is the typical appearance of Alzeihmer's dementia?
3. What is the typical appearance of Lewy body dementia?
4. What is the typical appearance of frontotemporal dementia (Pick's disease)?
5. What nuclear medicine tests can be used to study dementias?
6. How can you differentiate between Lewy body dementia and Alzeihmer's disease?

Back 6

1. Alzeihmer's, Multi-infarct (can be difficult to differentiate from other causes of dementia when diffuse), Frontotemporal dementia (Pick's), Lewy body dementia.
2. ALZEIHMER'S: Symmetrical disease in activity in the temporoparietal region. There is SPARING of the OCCIPITAL lobes, basal ganglia, and cerebellum.
3. LEWY BODY: Decreased activity in the temporoparietal region WITH OCCIPITAL lobe involvement.
4. PICK DISEASE: Anterior frontal and temporal hypoperufion/hypometabolism. SPARES OCCIPITAL lobes. Other disease processes that can have this appearance include depression, cocaine abuse, amyotrophic lateral sclerosis.
5.
- FDG-PET assesses brain metabolism.
- Brain perfusion SPECT (Tc99m HMPAO or ECD).
**Cerebellar activity tends to be higher with SPECT than in PET.
6. Lewy body dementia can be distinguished from Alzeihmer's disease by DaTSCAN SPECT which visualizes the dopaminergic system and demonstrates decreased basal ganglia uptake in DLB. NOTE: Parkinson's disease will also demonstrate decreased basal ganglia uptake.

Front 7

1. What is a written directive?
2. Can any radiologist perform a nuclear medicine study?

Back 7

1. Written directive is a prescription that is written by an authorized user for any therapeutic dose (I-131, Strontium, YYtrium, etc) of a radiopharmaceutical or any dose of I-131 > 30 MICROcuries.
2. No. Nuclear medicine studies must be done either by an authorized user or someone working under direct supervision of an authorized user.

Front 8

1. What is the patient preparation for HIDA scan?
2. What is the dose of CCK?
3. What are the agents used for HIDA scan and what are the doses?

Back 8

1. Patient must be fasting for at least 4 hours but not greater than 24 hours. If the patient has been fasting for greater than 24 hours, pretreatment sincalide.
2. 0.02 ug/kg IV slowly over 3 minutes. Mus weight of the 30 minutes prior to injecting HIDA tracer. Note: After treatment with sincalide, the gallbladder may fill preferentially without much radiotracer flowing into the small bowel.
3. Technetium labeled Mebrofenin or Desofenin.

Front 9

1. In the normal HIDA scan at which time does peak hepatic uptake occur?
2. In a normal HIDA scan what are some variant findings that can be confused with pathology?
3. What is the function of morphine? Dose?
4. What is a rim sign?

Back 9

1. Peak hepatic uptake occurs by 15 minutes. Note: Liver must be able to extract the radiotracer (impaired with hepatic dysfunction/hepatitis) from the blood pool.
2.
- Enterogastric reflux
- Pooling of radiotracer in the duodenum may mimic filling of the gallbladder.
- Some renal and bladder activity is always seen. If there is hepatic insufficiency, you will see greater GU activity.
3.
- Morphine causes spasm of the sphincter of Oddi resulting in increased hydrostatic pressure within the common bile duct therefore increasing the likelihood of visualizing the cystic duct if patent.
- 0.04 mg/kg (2-3 mg) IV. If gallbladder is not seen within 30 mins, then acute cholecystitis.
4. Increased radiotracer uptake in the liver adjacent to gallbladder fossa indicates severe cholecystitis.

Front 10

What are some indications for HIDA scan?

Back 10

1. Acute cholecystitis
2. Biliary atresia
3. Bile leak
4. Choledochal cyst
5. Biliary enteric fistula
6. Chronic gall bladder dysfunction (gallbladder ejection fraction)

Front 11

1. What is the dose of phenobarbital given for biliary atresia?
2. In cases of a bile leak, where does the bile normally flow?
3. What is a normal gallbladder ejection fraction?

Back 11

1. Five mg/kg per day for 5 days.
2. Bile flows via passive least resistance and thus you may not see the small bowel in cases of the bile leak. Look for increased activity in the right paracolic gutter and peritoneum.
3. Greater than 35%.

Front 12

1. What is the radiopharmaceutical used for detection of Meckel's diverticulum?
2. What are some potential pitfalls?

Back 12

1. Technetium pertechnetate.
2.
- Activity within the renal collecting system and ureter.
- Normal gastric activity which washes into the bowel.
- Inflammatory processes (Crohn's disease, appendicitis, intussusception, tumor). Increased radiotracer seen in these processes is secondary to increased blood pool activity due to hyperemia which washes out on delayed images unlike a Meckel's diverticulum which progressively increases in activity over time.
3. Cimetidine, pentagastrin, and glucagon increase the sensitivity for detection of Meckel's diverticulum. Make sure that the pt has not had a recent barium study as it will attenuate the radiation.
- Study lasts 30 mins - 1 hour.
- In clinical practice, only cimetidine IV is given. If no IV, then oral cimetidine has to start earlier.
- Uptake in the RLQ focus is COINCIDENT with uptake in the stomach.

Front 13

1. What is a distribution of sulfur colloid?
2. What are the indications for sulfur colloid scan?
3. What is colloid shift?

Back 13

1. Sulfur colloid goes to the reticuloendothelial system (liver, spleen, bone marrow).
2.
-Evaluate for FNH which are hyperintense or isointense to background liver in 2/3 of the cases. 1/3 of FNH do not demonstrate sulfur colloid uptake.
-Evaluate for GI bleed (sulfur colloid stays in the blood pool for a short amount of time and thus the patient should be actively bleeding at the time of the study).
-Evaluate for splenules. Heat damaged red blood cells is a better examination for this indication.

3. Colloid shift occurs when there is hepatic dysfunction resulting in increased uptake in the spleen and bone marrow.

Front 14

1. What tracers were used for tumor imaging?
2. FDG PET scan is not used from a tumors?

Back 14

1.
-FDG PET scan
-OctreoScan (In-111 pentetriotide): Use for neuroendocrine tumors (carcinoid, islet cell tumors, paraganglioma in the neck)
-I-123 MIBG: Used for pheochromocytoma and neuroblastoma

2. GU tumors (renal, bladder, prostate) due to increased background uptake.

Front 15

1. What is in preparation for FDG PET scan?
2. What is a standard uptake value (SUV)?
3. What is considered an abnormal SUV?

Back 15

1. For tumor evaluation, patient's must be n.p.o. for 6 to 8 hours. Note that a recent meal (high as the level) will increase muscle uptake. High glucose levels will impair FDG uptake or tumors due to competitive inhibition. Therefore do not due to scan if the patient's glucose is greater than 200.
2. Semiquantitative value expressing intensity of uptake relative to the average whole body distribution.
3. SUV values greater than 2.5 are suspicious for malignancy.

Front 16

Describe the workup of a lung nodule.

Back 16

If a lung nodule is found on CT scan and is greater than 7 mm in size, we proceed with the biopsy if it is feasible. However if the biopsy is difficult, we can do a PET scan. If the PET scan demonstrates that the nodule is hot, then biopsy must be performed. If the nodule is cold it suggest benignity, however, continued follow-up is necessary as low grade malignancies cannot be excluded. Therefore, never read a nodule as negative and stop the evaluation.

Front 17

1. What are some false positives on PET scan?
2. What is the characteristic distribution of brown fat?

Back 17

1.
-Infection (fungal, TB, pneumonia)
-inflammation (sarcoidosis, rheumatoid nodule, diverticulitis)
-others (muscle uptake, brown fat, thymic rebound, diffuse thyroid uptake --Graves' disease/Hashimoto's thyroiditis)
-benign tumors (thyroid nodules)
-fractures
2. Neck, chest, paraspinal. Brown fat activity can be blocked by giving diazepam and beta-blockers.

Front 18

1. What is a mechanism of uptake for MIBG?
2. What is a normal distribution for MIBG?
3. What is the most common indication for an MIBG scan?

Back 18

1. MIBG is a norepinephrine analog.
2. Normal activity is seen in the salivary, parotid, and submandibular glands, myocardium, liver, and faint adrenal glands. Normally, Lugol's solution was given to block the thyroid. If the patient has not taken the Lugol solution, then activity can be seen within the thyroid.
3. MIBG scan is most commonly used for pheochromocytoma and neuroblastoma.

Front 19

1. What is a mechanism of uptake of pentotreotide?
2. What is a normal distribution for pentotreotide?
3. What are the most common indications for pentotreotide imaging?

Back 19

1. Somatostatin receptor analog.
2. Normal activity is seen in the kidneys and spleen. Lesser activity is noted in the liver and bowel.
3. Neuroendocrine tumors (carcinoid, islet cell tumors, glomus tumors in the neck). Neuroblastoma and pheochromocytomas are better imaged with MIBG.

Front 20

1. What are the causes of hyperthyroidism?
2. What is Marine-Lenhart disease?
3. At what size do autonomous nodules cause supression of the remainder of the gland?

Back 20

Hyperthyroidism is most commonly caused by Graves' disease

(diffuse toxic goiter), multinodular toxic goiters, and hot soli

tary nodules. Struma ovarii (ectopic thyroid tissue in the ovary)

and thyroiditis are rarer causes of hyperthyroidism.
2. Graves'

disease with hyperplastic nonautonomous nodules. In this case

the "Graves' " pattern is modified to show not only increased

uptake and an enlarged gland, but also cold nodules within that

gland (from suppressed hypertrophic nodules caused by the

Graves' outpouring of thyroid hormones).
3. autonomous nodule over 4 cm in size usually causes

suppression of the remainder of the thyroid gland through the

pituitary gland's feedback control with thyroid stimulating

hormone (TSH). If the nodule is 1 to 2 cm in size, one may see

normal thyroid gland radiotracer uptake in the background of

the hot nodule.

Front 21

Infection scanning with gallium

Back 21

- if gallium activity is greater than bone scan activity--suspicious for infection.
- if bone scan activity is greater than gallium, then no infection is present.
- if activity in bone scan and gallium scan is equal, then indeterminate.

Front 22

Transient ischemic dilatation

Back 22

- Look for enlargement of left ventricular cavity on stress images.
- Look for increased right ventricular uptake
- Indicates balanced triple vessel disease
- enlargement of left ventricular cavity size may be due to subendocardial ischemia.

Front 23

Medical event

Back 23

- Requires verbal and written notification to the NRC.
- Wrong pt/radiopharmaceutical/route of administration if whole dose > 5rem or single organ dose > 50rem
- Administered activity >20% of prescribed
- Unintended administration to fetus must be reported if fetal dose >5rem.
- If I-131 is administered to a pt who is later found to be pregnant (shortly after dose was given): give IV fluids, encourage frequent voiding to reduce gamma dose to fetus

Front 24

Off peak imaging

Back 24

- Most commonly occurs when the technologist forgets to switch the photopeak from 122 keV (photopeak of Co-57) to 140 keV (photopeak of Tc).
- Results in imaging of scatter and thus poor resolution of images.
- NOTE: Images will appear fuzzy if you scan early (i.e. during the blood pool phase).

Front 25

Detection of R to L shunt on V/Q scan

Back 25

Right to left shunt on perfusion studies of the lungs will show uptake in the thyroid bed/salivary glands. To confirm that the activity is from a R - L shunt, you can image the brain. Activity in the brain will only be seen with R - L shunt.
- Shunting > 5-10% is considered significant. You can quantify shunt by determining the ratio of counts in the brain to whole body count.
- In cases of known or suspected shunt, the number of particles should be reduced to 100,000. The reduced number of particles also applies to children, pregnant women, and pts with pulm HTN.

Front 26

Superscan

Back 26

METASTATIC:
- typically inhomogeneous with focal lesions seen over diffusely increased radiotracer activity in the bones.
- involves the axial skeleton
METABOLIC:
- involves both axial and appendicular skeleton.
- uniform distribution of activity
- disproportionate increase in calvarial uptake.
- Renal osteodystrophy, hyperthyroidism, osteomalacia.
PAGET'S DISEASE
MYELOPROLIFERATIVE/ MARROW INFILTRATIVE D/O:
- Lymphoma, leukemia, mastocytosis, and myelofibrosis.
- involves both axial and appendicular skeleton and thus mimics metabolic superscan.

Front 27

Hardware related osteomyelitis

Back 27

Dual isotopes -- In labeled WBC and Tc-Sulfur Colloid.
- Corcordant activity = infection.
- Activity seen only on Tc-SC = marrow packing

Front 28

Mimics of active bleeding on tagged RBC study

Back 28

- Penile activity
- Uterine activity in a menstruating female
- Inflammatory bowel disease
- Hypervascular tumor
- Free Tc (free Tc will go to stomach where it will enter the small bowel and undergo peristalsis mimicking small bowel bleeding. Therefore, image the thyroid to look for free Tc)

NOTE: activity in the above locations does not have peristalsis.

Front 29

Renal artery stenosis:

Back 29

- Adequate fluid hydration prior to and blood pressure monitoring during a Captopril scan is important.
- A positive scan suggests hemodynamically significant RAS and predicts benefit from revascularization.
- Base renal scan with MAG 3 is compared with a post-Captopril scan with MAG-3 for diagnosis.
- False positives for bilateral RAS include dehydration, bilateral obstruction, and significant hypotension.
- For MAG3 studies, the kidney with RAS demonstrates lack of clearance due to drop in GFR.
- For DTPA studies, RAS demonstrates lack of uptake in the affected kidney.

Front 30

1. What is the ddx of cold thyroid nodule?
2. What are the ultrasound findings of thyroid CA?
3. What are the ultrasound findings of colloid cyst?
4. What are the ultrasound findings of nonfunctioning adenoma?

Back 30

1.
- Colloid cyst (40%)
- Non-functioning adenoma (40%)
- Thyroid CA (20%)
2. Thryoid CA: Solid, hypoechoic, hypervascular mass with microcalcifications.
3. Colloid cyst: cystic lesion with inspissated colloid which is hyperechoic and demonstrates ring-down or comet tail artifact.
4. Well-encapsulated with a hypoechoic halo. Thyroid adenomas can be functional or non-functional. Functioning adenomas may become hyperplastic and cause hyperthyroidism. They require a higher dose of I-131 typically around 30mCi.

NOTE: a hot nodule on Tc-pertechnetate needs to worked up further with I-123 study as it may be discordant.

Front 31

Focal uptake on Octreoscan

Back 31

1. Neuroendocrine tumors (carcinoid/pancreatic islet cell tumors). NOTE: neuroblastoma and pheochromocytoma are more commonly imaged with I-123 MIBG.
2. Metastatic neuroendocraine tumors (small cell lung CA, medullary thyroid CA, breast CA, lymphoma)
3. Granulomatous disease (TB, sarcoid).

Front 32

1. What agents are used for brain perfusion studies?
2. When using DTPA to evaluate for brain death, do you expect to see parenchymal uptake?

Back 32

1. Tc-HMPAO or Tc-ECD. Lipophilic agents that cross the blood brain barrier and enter brain parenchyma.
2. DTPA does not cross the BBB. Look for activity in the the intracranial vessels (circle of Willis) and venous sinuses.

Front 33

Uptake on I-131 scan

Back 33

- When a pt is diagnosed with thyroid cancer, they are typically treated with a thyroidectomy.
- Following thyroidectomy, a low dose I-131 (<5mCi) or I-123 (2mCi) scan is done to evaluate for metastatic disease. Before the scan, the pt is made hypothyroid by withdrawing Synthroid (for 4 weeks -- check TSH level to make sure it is elevated) or giving recombinant TSH (thyrogen) to stimulate uptake in thyroid tissue.
- I-131 ablation is then performed; the dose depends on whether the pt is being treated for residual thyroid tissue (30-75mCi), local mets to cervical lymph nodes (75-150mCi), or distant mets (150-200mCi).
- Imaging is performed 7-10 days after the ablation therapy.
- Follow up of pts includes yearly serum thyroglobulin levels and I-131 scans for 2 years.
- I-131 treatment can be repeated in the event of recurrent disease with 6mos - 1 year interval between ablation doses to avoid bone marrow suppression.
- On the post-therapy scan, you expect to see uptake in the neck from residual thyroid tissue. This will give rise to star artifact 2/2 septal penetration due to high energy photons of I-131 (364 keV).
- Physiological uptake is seen in salivary glands. Swallowed activity may mimic cervical adenopathy -- give H2O to clear the activity.
- If thyroglobulin levels rise and I-131 scan is negative, do PET scan.

Front 34

Gallium

Back 34

- Mode of localization = resemblance to ferric ion and calcium analogue.
- Photopeak = 93, 184, 296 keV
- Focal uptake of gallium is non-specific and may be seen in inflammation, infection, or neoplasm.
- Neoplasm = *lymphoma, HCC, lung CA, sarcoma (except Kaposi), melanoma.
- Inflammation = *sarcoidosis
- Infection = spine infections, osteomyelitis, pulmonary infetions (PCP = diffuse increased lung activity, TB, fungal diseases).
- Physiologic renal excretion is seen during the first 24 hours with primarily GI excretion thereafter.

Front 35

Focal increased hepatic uptake on sulfur colloid scan

Back 35

- FNH
- Regenerating nodular cirrhosis: regenerative nodules are composed primarily of hepatocytes that are surrounded by coarse fibrous septations. They have normal sulfur colloid uptake and can appear as a hot spot surrounded by a region of diminished uptake.
- Budd-Chiarri syndrome: the caudate lobe continues to work normally and thus accumulates sulfur colloid while the rest of the liver does not due to vascular congestion and necrosis of the liver parenchyma.
- SVC syndrome: collateral vessels return blood via the left internal mammary and left umbilical veins into the left lobe of the liver, resulting in a focal hot spot when sulfur colloid is injected into the upper extremity. Injection in the lower extremity results in a normal scan.

Front 36

Focal uptake on Indium 111 labeled WBC scan:

Back 36

- Infectious enteritis/colitis
- IBD
- GI bleeding (WBC as well as RBC pass into the bowel lumen)
- Swallowed activity from sinusitis/pharyngitis.

Front 37

1. What agents are used for infection/inflammation?

Back 37

1. In-111 labeled WBC, Tc-99m HMPAO labeled WBC, Gallium.
2. Gallium is superior to In-111 for detection of vertebral osteomyelitis.
3. The patient's WBCs (requires 50cc of blood) are labeled with In-111 in vitro. Imaging is performed at 24 hours, unless you are concerned about IBD in which case imaging is done at 1-4 hours to help localize the site of inflammation. Earlier imaging allows localization as the WBC's will peristalse away once in the lumen of the bowel
- Early transient pulmonary activity is normal.
- Normal increased activity is seen in surgical wounds, around catheters.
- Tc-HMPAO is used in kids to decrease radiation dose. It must be imaged early (before 4 hours) to avoid interfering with physiologic colonic activity.

Front 38

QC

Back 38

- Daily camera QC includes extrinsic flood with Cobalt 57 sheet source placed on the camera with the collimator on.
- Spatial resolution/linearity is tested weekly with a bar phantom between the Co-57 source and collimator.
- Intrinsic flood (collimator off) is done monthly using a Tc-99m point source.

Front 39

Artifact

Back 39

PHOTOMULTIPLIER TUBE FAILURE:
- PMT tubes are located behind the sodium iodide crystal and convert light impulses from the scintillation event into an electrical signal.
- Look for round defect in the flood image.
CRYSTAL DEFECT:
- gamma ray photons produce a scintillation event with the sodium iodide crystal.
- Look for branching white pattern.
COLLIMATOR DEFECT:
- collimator helps to localize the radionuclide by allowing only those photons traveling in an appropriate direction to interact with the crystal.
- Lead in collimator can be dented, resulting in bending and distortion of septa.
- Look for focal areas of decreased activity on the flood field image.

Front 40

1. What is the patient preparation for PET scan?

Back 40

1. 4 hour fasting, no recent regular insulin, serum glucose < 200.
Standard PET imaging is perfromed from teh skull base to teh proximal thighs 45 to 60 mins after injection of 15 mCi of FDG. Corresponding low dose CT is peformed for attenuation correction.
2. FDG releases a positron which annihilates with a nearby electron, producing two 511 keV gamma photons at 180 degrees.

Front 41

1. What is ammonium -13 used for?

Back 41

1. It is a cardiac perfusion tracer. It canbe used in conjunction with FDG-PET scan to determine if region of abnormal perfusion seen on ammonium -13 scan represents hibernating or infarcted myocardium.

Front 42

Normal Pressure hydrocephalus

Back 42

Findings:
Tracer reflux into ventricles
persistent ventricular activity > 24hrs
Dose / tracer: 0.5 mCi In-111 DTPA
Technique:
LP – inject
posterior image over TL spine - confirm injection in 15-30 min
image at 4, 24, 48 hrs (2, 12, 24 hrs kids)
Normal study:
basilar cisterns - 4hrs
convexities - 24 hrs
ddx:
obstructive, communicating hyrocephalus (e.g. meningitis)

Front 43

Absent thyroid uptake

Back 43

Findings:
No thyroid activity seen on a 99m-Tc study
ddx:
Hyperthyroid
painful:
subacute thyroiditis
painless:
exogenous thyroid
Hypothyroid
painless:
Hashimotos's
ablated thyroid
Recent I+ study
Congenital absence (v. rare)

Front 44

Idiopathic pulmonary hemosiderosis

Back 44

Findings:
Intense lung and renal activity = hemosiderosis & nephrocalcinosis
ddx:
prior lung scintigraphy
alveolar microlithiasis
secondary pulmonary hemosiderosis and ossification
mitral regurgitation

Front 45

How do you tag RBCs?

Back 45

- We do in vitro tagging w/the Ultratag kit
- Draw up 3cc of pt’s blood
- Place in the vial w/the stannous chloride disc
- Wait 5 min
- Add acid, buffer & Tc99m, inverting in b/wn each add’n (whole procedure should take only 1 min)
Let sit 15 min
Re-inject into pt

Front 46

Energy peaks and alf lives

Back 46

I-131:
- Major energy peak = 364 keV
- t1/2 = 8 days
***************************************************
Thallium 201
- Major energy peak = X-ray 69 - 83 keV (93%); Gamma: 167 keV (9.4%)
- T1/2 : 3 days
- Dose: 3 mCi
- MOA: K+ analogue
**************************************************************

Front 47

Quality of scans

Back 47

POOR QUALITY:
- I-131
- Gallium
- Low dose In-111
INTERMEDIATE QUALITY:
- I-123
- Thallium
GOOD QUALITY:
- Tc-99m
- High dose In-111 (Octreoscan, antibody scan)

Front 48

Radiation dose limits:

Back 48

RADIATION WORKER:
- Whole body = 5000 mrem/yr
- Eye dose = 15,000 mrem/yr
- Extremity dose = 50,000 mrem/yr.

PREGNANT RADIATION WORKER:
- radiation limit only applies to a woman who has officially declared her pregnancy to the employer in writing
- 500 mrem for the 9mo gestation
- Wear collar monitor & monitor under apron.

GENERAL PUBLIC:
- 100 mrem/yr

Front 49

Breast feeding instructions

Back 49

- Interrupt breast feeding for 24-48 hrs for any Tc99m study.
- Cease nursing w/any I-131, Ga-67 or Tl-201 administration.

Front 50

What types of personal radiation detectors are in use?

Back 50

- Film
- Thermoluminescent detectors (TLD): can only be read once.
- Optically stimulated luminescence (OSL):
Can be read multiple times
- Self-reading dosimeters: Pencil dosimeter and digital personal dosimeter