Topic 4 Flashcards
The acquisition of a single image or snapshot of a particular structure. the simplest type of nuclear medicine image that looks like a single snapshot of a target anatomy.
•Records and demonstrates all radioactivity from the patient above and below the region of interest
Uses low radiopharmaceutical activity levels.
• Rationale: to minimize radiation exposure to the patients
• Disadvantage: images must be acquired for a preset time or minimum number of counts or radioactive emissions.
• 30 seconds and 5 minutes – time it takes to obtain a sufficient number of counts to produce a satisfactory image.
planar/Static imaging
Examples of planar/static imaging
Lung scan, spot bone scan images, and thyroid images.
This imaging uses a specially designed moving detector or system to produced an image of the entire body or a large body section.
•Gamma Camera collects data as it passes through the body
Whole body imaging
Whole-body Imagine systems:
a.For whole-body bone scans
b.For whole-body tumor imaging.
c.For whole-body abscess imaging
d.For other clinical and research applications.
A flow of a particular structure.
•This provides a series of images that demonstrates blood flow in the body within specific organs.
•This generally used to evaluate blood perfusion to the tissue.
Dynamic Images:
•These can be thought as it sequential or time-lapse image.
•These display the distribution of a particular radiopharmaceutical over the specific period
Dynamic imaging
Common applications of dynamic imaging
1st-pass cardiac studies
Hepatobiliary studies
Gastric emptying studies
Rationale: because all examinations is based on the distribution of radiopharmaceutical within the body.
●In vivo: within the living body
In vivo examinations
Patient preparation:
●Most tests requiring no special preparations
●All metal objects must be removed – because they may mimic or attenuate pathologic conditions.
●Patient may resume all normal activities after completion of a routine procedure
●A survey procedure to evaluate patients with malignancies, diffuse musculoskeletal symptoms, abnormal laboratory results and hereditary or metabolic disorders
●Radiopharmaceutical: Localize in bone and soft tissue structures.
●Skeletal Areas of increase Uptake: result of tumor, infection or fracture.
Bone scintigraphy
Performed to look at the skeletal system and to detect abnormalities such as metastases, stress fracture or a loose prosthesis.
•Can detect a fracture 2 years after an injury
Bone scan
Bone scan Major factors that Influence Uptake:
•Regional blood flow
•Osteoblastic activity
•Extraction efficiency
Radiopharmaceutical used in bone scan
•Tc-99
•Tc-99m
•Tc-99m
Adult dose:
labelled diphosphates
hydroxemethylene diphosphate (HDP)
Methylene diphosphate (MDP)
20 mCi (740 MBq)
Routine Scanning in bone scan
begins 2 – 3 hours after the injection and it takes 30-40 minutes.
A noninvasive study
Purpose:
•Assess cardiac performance
•Evaluate myocardial perfusion
•Measure viability and metabolism
Nuclear cardiology
Procedures in nuclear cardiology
•Exercise radionuclide angiography
•Thallium
•Technitium
201 myocardial perfusion study
99m sestamibi myocardial
perfusion study.
•Performed with a patient using a treadmill or stationary bicycle.
•Used to alter the blood flow to the heart.
Stress test
During stress test what is monitored during procedure?
Heart rate
Ecg
Blood pressure
Symptoms
Alternative to stress test
•Used in place of the exercise test
•Used to alter the blood flow to the heart
•For patient who cannot exercise
•For patient with peripheral vascular disease, neurological problems or musculoskeletal problems
Pharmacological intervention
▪ Used to measure left ventricular ejection fraction.
▪Used to evaluate left ventricular regional wall motion.
▪ requires that the blood be labelled with Tc-99m
▪Cardiac cycle: Divided into 16-20 frames during a gated acquisition.
▪Radiopharmaceutical: Tc-99m labelled red blood cells
▪Adult dose: 25-40 mCi (based on patient’s body surface – height and weight)
Gated exercise radionuclide angiography
Gated exercise radionuclide angiography scanning
▪Begin immediately after the injection
▪Takes about 1 hour
▪ Anterior position
▪Left lateral position
▪Left anterior Oblique position
●A SPECT study that is used to identify perfusion defects in the left ventricular wall.
●Useful for assessing myocardial viability in patients with known Coronary Artery Disease.
●Useful for evaluating patients with revascularization.
Spect myocardial perfusion study
Stress thallium-201 myocardial perfusion study
Radiopharmaceutical:
●
●
●For obese patients
●Used so that higher dose can be administered
●Mode of Administration(MOA) –
●Th-201 thallous chloride
●Tc-99m Sestamibi
Intravenously while the patient is physically stressed on a threadmill
Adult dose:
a. Stress study:
●Administered intravenously before rest study
b. Delayed Study:
●Administered intravenously before delayed
c. Rest Study –
●Administered intravenously before rest study
3 mCi of Th201 thallous chloride
1 mCi of Th201 thallous chloride
4 mCi of Th201 thallous chloride
Scanning in stress thallium-201 myocardial perfusion study
● Anterior planar image of the chest and heart.
●A 180 degree SPECT study. (45 degree RAO to 45 degrees LPO)
Stress Thallium-201 Myocardial Perfusion Study
Images: 2 sets
A.
B.
NOTE: During Th-201 myocardial perfusion study,
a.After the stress test
b.Several hours after the patient is rested.
the symptoms may be apparent at rest.
●Used to assess myocardial salvage resulting from the therapeutic intervention in acute infarction.
●Used to determine the myocardial blood flow during periods of spontaneous chest pain.
Technetium-99m Sestamibi Myocardial Perfusion Study
First Pass Flow study
Technetium-99m sestamibi myocardial perfusion study
●
Used to evaluate
●
●
●Performed with a rest or stress Tc99m sestamibi myocardial perfusion scan
●Heart function
●Ejection fraction
Radiopharmaceutical: Technetium-99m Sestamibi
Adult dose:
a.Stress study:
● administered intravenously at peak
b. Rest study:
● administered intravenously before rest study
Note:
__- provides optimum image quality
__- more convenients in px, technologist and physician
10-30 mCi of Tc-99m sestamibi
10-30 mCi of Tc-99m sestamibi
2 day protocol
1 day protocol
Technetium-99m Sestamibi Myocardial Perfusion Study
Scanning:
▪
▪
▪
▪ SPECT imaging done 30-60 minutes after injection.
▪ for both stress and rest study
▪ delayed images done 4-6 hours after injection
Brain perfusion imaging spect study
▪ Useful in the evaluation of patient with:
A.
B.
C.
D.
E.
▪imaging agent:
a.Stroke
b.Transient Ischemia
c.Alzheimer’s disease
d.Epilepsy
e.Parkinson’s disease
Capable of penetrating the intact blood brain barrier (BBB)
BRAIN PERFUSION IMAGING SPECT STUDY
Radiopharmaceutical:
*
*
▪Dose: 20 mCi
▪ Tc-99m ethylcysteinate diamer (ECD)
▪ Hexamethylpropyleneamine oxime
(HMPAO)
Brain perfusion imaging spect study
Scanning:
Begins __ after Tc-99m ECD
Begines __ after Tc-99m HMPAO
Note: “the patient is placed in a quiet, darkened area before injection and instructed to close the eyes – helpful in reducing uptake of the tracer in the visual cortex.”
30 minutes
1 hour
Useful in diagnosis of CSF leakage after the trauma or surgery.
Useful in the diagnosis of normal pressure hydrocephalos
Radionuclide cisternography
Performed to evaluate the size, shape, nodularity and functional studies of the thyroid gland.
Used to screen for thyroid CA.
Used to differentiate hyperthyroidism, nodular goiter, solitary thyroid nodule and thyroiditis.
Used to determine the relative function of nodules in different regions within the thyroid.
Thyroid scan
Thyroid scan
Radiopharmaceutical:
__
__ – Advantages: Low patient dose, No particulate radiation and well-resolved images.
Adult Dose:
__ of Tc-99m pertechnetate
__ mCi in I-123
Tc-99m pertechnetate
I-123
5 mCi
0.5-1.5
Factors that affect thyroid uptake
Thyroid medication
Foods
Drugs
Iodine-containing contrast agents.
-
Used to obtained anterior, left oblique and right anterior oblique thyroid images
Used to obtained a 6 inches (15 cm) anterior neck image.
Pinhole Collimator: A thick, conical collimator that allows for magnification of the thyroid.
Begin 20 minutes after the injection
Used in gamma camera with a pinhole collimator
Useful in distinguishing between thyroiditis and Grave’s disease (toxic nodular goiter or Plummer’s disease)
Used to evaluate the function of the thyroid gland.
“Uptake” – expressed as the percentage of the dose in the thyroid gland at a given time after administration.
I-131 thyroid uptake measurement
High tyroid uptake
*
*
*
*
Low thyroid uptake
*
*
*
*
Thyroid with increased activity
Overactive thyroid gland
Hyperthyroidism
May indicate grave’s or plummer’s disease or toxic nodular goiter
Thyroid with decreased activity or less functional
Thyroid cannot visualized during imaging
More common in women than men
May indicate thyroiditis
Radiopharmaceutical
I-131 Sodium iodide
Mode of administration: __
Adult Dose:
Standard Uptake Test: __ of I-131
Uptake readings: acquired at __ and/or at __
NOTE: “thyroid therapy with I-131 can be given to reduce the function of the thyroid.”
Orally
3-5 microcurie
4-6 hours /24 hours.
Recommended for the locating residual thyroid tissue in patients with thyroid carcinoma.
Recommended for the recurrent thyroid CA cells in patients with thyroid carcinoma.
NOTE:
__ – performed 1-3 months after thyroidectomy. (To check for residual normal thyroid tissue)
__ – performed after the residual thyroid tissue has been ablated or destroyed. (To check for the metastatic spread of the CA.)
Neck/total body I-131 scan
Neck I-131 Scan
Total Body I-131 Scan
Neck/total body scan
Radiopharmaceutical: __
Mode of Administration: __
Adult dose: __
Total Body Scan – __
Neck Scan – __
__ – injected on each two days before the dose administration to allow the patient to remain on thyroid medications.
I-131 Sodium Iodide
Orally
3-5mCi
1 mCi
Thyrogen
Scanning:
A. __
starts 24 hours after the administration of the dose
Anterior Planar neck
B. __
Starts 48 hours after the administration of the dose
Anterior and Posterior whole body.
Neck Imaging
Total Body Scan
Used to assess the functional status of different internal and accessory organs of the alimentary canal
-
Other examinations are:
*
*
*
*
Gastrointestinal nuclear medicine studies
Gastric emptying study
Hepatobiliary scans
Gastroesophageal reflux scan
Spleen scan
Cystogram
Gastrointestinal bleed scan
__ – performed to evaluate the motility of the solids and liquids through the GI tract
__ – performed to evaluate gallbladder function, performed to identify the bile leak following the removal of the patient’s gallbladder.
__ – performed to identify the location of the bleeding in the stomach, small intestine or large intestine.
Gastric Emptying Study
Hepatobiliary Scan
Gastrointestinal Bleed Scan
Used to evaluate the liver for functional disease: Cirrhosis, Hepatitis, Metastatic disease
Used to look for residual splenic tissue following splenectomy.
Used to assess the functional status of liver and spleen.
Used to determine whether certain lesions found with other methods may be benign (Advantage: obviating the need for biopsy.)
Liver/spleen scan
Liver/spleen scan
Uptake:
Normal Patients:
__ uptake in the liver
__ uptake in the spleen
The rest in the bone marrow
Radiopharmaceutical
__
__
80-90%
5-10%
Tc-99m Sulfur Colloid
Tc-99m Albumin Colloid
Mode of administration:
Scanning: Images taken are:
Anterior
Posterior
R and L anterior Oblique
R and L lateral
R Posterior Oblique
Note: “Gastric emptying and Hepatobiliary scans are the most commonly performed GI.”
Intravenously
A reliable, noninvasive procedures
Used for evaluating the anatomy and function of the systems in nephrology, urology and kidney transplantation.
Note: “the radiopharmaceutical that is administered is cleared by normally functioning kidneys in about 20 minutes.”
Genitourinary nuclear medicine studies
Used to assess renal perfusion and function in patients with renal failure, renovascular hypertension and renal transplant.
Radiopharmaceutical:__
Secreted primarily by the proximal renal tubules
Not retained in the parenchyma of normal kidneys.
Dynamic renal scan
Tc-99m Mertiatide (MAG3)
Mode of administration: __
Adult Dose: __
Patient Preparation: Patient must be well __ before all renal studies.
Scanning:
Initiated immediately after the injection
It should be delayed for 24 hours after contrast studies
Intravenously
10 mCi
hydrated
Images taken:
Over the __
Centered at the level of 12th rib
__ – for transplanted kidneys.
posterior lower back
Anterior pelvis
Hematologic Nuclear Medicine Studies
Two Types:
__
__
Non-imaging Studies:
__ – for quantitating biologically important substances in the serum or other body fluids
__- for evaluation of physiological function.
In vitro studies
In vivo studies
In vitro radioimmunoassay (RAI)
In vivo radioimmunoassay (RAI)
2 types of measurements:
__ is made after administration of radiopharmaceutical
__ Vit B12 absorption (Schilling test)
Quantitative measurement
Physiologic Event Measurements:
Used to locate inflammation infection and abscess in any organ or tissue within the body
__: useful for diagnosis and localization of infection and inflammation.
Infection nuclear medicine
Gallium-67 and Indium-labelled white cell scans
Useful for demonstration of pulmonary perfusion using limited transient capillary blockade
Useful in the assessment of the ventilation using an inhaled radioactive gas or aerosol.
Most commonly performed to evaluate:
*
*
*
*
Resporatory nuclear medicine studies
Pulmonary emboli
COPD
Chronic bronchitis
Emphysema
Lung Ca.
In respiratory nuclear medicine studies
Note: __ is usally performed 1st followed by the __
Ventilation, perfusion scan
Used in combination with lung perfusion scans
__: used for a ventilation study.
Characteristic:
Must be absorbed significantly by the lungs.
Must be diffuse easily
Radiopharmaceutical: __
Mode of administration: __
Xe-133 lung ventilation scan
Gas
Xe-133 gas
inhalation
Adult Dose: __
Scanning:
Starts immediately after __
The ventilation study must precede the __
Images are taken:
__– for the first breath equilibrium and washout
__– for the first breath equilibrium
15-30 mCi
inhalation
Tc-99m perfusion scan
Posterior and Anterior
LPO & RPO
Xe-133 lung ventilation scan
Note: the body usually absorbs less than __ of the gas
15%
Radiopharmaceutical:
Adult dose:
Scanning:
Starts __ after the injection
Images are taken:
Anterior/posterior
R and L lateral
R and L Anterior Oblique
R and L Posterior Oblique
Tc-99m Macroaggreated Albumin: Lung perfusion Scan
Tc-99m MAA
4 mCi
5 minutes
__: taken within 24 hours of the lung scan
for accurate interpretation of the lung scan
to determine the probability for pulmonary embolism.
Chest radiograph
Lung ventilation scan-
Lung perfusion scan
Xe-133 gas (inhalation)
Tc-99m MAA (injection)
