Tracer Notes


Table Of Contents

q��� Cardiovascular Imaging. 3

q��� Pulmonary System.. 3

q��� Skeletal System.. 3

q��� Gallium 67 Citrate. 3

q��� Indium -111 Labeled Leukocytes. 4

q��� Technetium -99m HMPAO - Labeled Leukocytes. 4

q��� Liver Spleen study. 4

q��� I-123 metaiodobenzylguanidine (MIBG) 4

q��� Octreotide. 4

q��� Hepatobilary System.. 4

q��� Gastointestinal System.. 5

q��� GU.. 5

q��� Thyroid imaging. 6

q��� Parathyroid. 6

q��� CNS. 6

q��� LYMPHOSCINTIGRAPHY.. 6

q��� Dose 5 mCi 8

q��� Dose 10 mCi 8

q��� Dose 20+ mCi 8

q��� Other 8

 


q  Cardiovascular Imaging

o       Thallium 201- chloride

       2-3.5 mCi

       Window 69-83 KeV, can use 2nd window of 167 KeV to increase counts.

       Critical organ = Kidneys

o       Technetium-99m sestamibi

       Same day rest and stress: initially done with 10mCi, 2nd is done 3-4 hrs later using 20-30 mCi (account for residual activity)

       Critical Organ = GB, if no GB then Colon

q  Pulmonary System

o       Tc-99m macroaggregated albumin (Tc-99m MAA) - typical 5 mCi dose 500,000 particles

       Critical organ = Lungs

o       Tc-99m DTPA give 20-30 Mci Aerosol -1 MCi (reaches lungs)

o       Xenon

o       Single Breath

       Deep inspiration, patient hold breath while 100,000 count image is acquired

o       Equilibrium

       Patient breaths air and Xenon and image acquired every 60 sec for 3 min

o       Washout

       Patient breaths room air and serial images are obtained

       Good for air trapping in COPD, will show inreased tracer on delayed images

q  Skeletal System

o       Techneium 99m MDP

       � - 6 hrs

       Kev =140

       Dosage 15-25 mCi

       Critical organ = bladder

q  Gallium 67 Citrate

o       � life 78 hours

o       circulates bound to transferrin

o       Uptake highest in liver but also spleen ,salivary glands, bone marrow and Lacrimal gland, kidneys only faintly seen at 48-72 hrs

o       Photo peaks are 93, 185 and 300

o       Infection 5 mCi

o       Tumors 10 mCi

o       Critical organ = Colon

o       Typically image at 48 (BEST) and 72 hrs

q  Indium -111 Labeled Leukocytes

o       � life = 67 hrs

o       Typically image at 24 hr

o       Photopeak = 173 and 247 Kev

o       Critical organ = Lungs

o       Dose = 500 uCi in adults

q  Technetium -99m HMPAO - Labeled Leukocytes

o       Dose - 10 mCi

o       Critical organ = Colon

o       Image at 1-2 hrs for IBD 4-6 for other (osteo, etc..)

o       Better for peds due to lower radiation dose and extremities

q  Liver Spleen study

o       T99m-sulfur or albumin

o       Dose = 4-6mCi; inj-to-imaging 20min

q  I-123 metaiodobenzylguanidine (MIBG)

o       pheochromocytoma and neuorblastoma

o       precursor of norepinephrine

o       Normal MIBG activity should be confined to the heart, salivary glands, liver, spleen, and bladder, with some excretion into the GI tract.

o       Image at 24, 48 and 72 hours

o       Dose - 10 mCi

q  Octreotide

o       Imaging is useful for detecting a variety of neuro-endocrine tumors which contain somatostatin receptors, including VIPomas, insulinomas, gastrinomas and pheochromocytomas

o       Pentetreotide is a somatostatin analog (In-111 Pentetreotide (Octreotide)

o       Dose = 6 mCi

o       Accumulates in the thyroid and salivary glands, spleen, liver, and kidneys, with excretion into urinary bladder and bowel (mainly on 24 hour images)

q  Hepatobilary System

o       Tc-99m mebrofenin (Choletec)

o       Dose � 5 mCi

o       Critical organ = Colon

o       Sincalide (Kinevac) is synthetic CCK dose is - .02 �g/kg

o       Morphine - .04mg/kg about 2 mg

q  Gastointestinal System

o       Diabetic Gastroparesis

       Most common cause (vagal nerve damage?)

       1 mCi of technetium-99m sulfur colloid microwaved with 30 grams of liver pate.

o       Sulfer Colloid (GI bleed)

       Dose - 10 mCi

       Critical organ = Liver

o       Meckel scan

       Tc99m-pertechnetateDose - 10mCi for child 20 for adult

       Critical organ = Stomach

o       GI Bleeding Study

       Tc-99m Tagged Red Blood cells

       Critical organ = Heart

       Dose = 20 mCi

       Use in vitro Ultratag KIT

o       Denver shuntogram

       Peritoneal-venous shunting (Denver shunt) is used in cases of intractable ascites

       5.5 mCi Tc-99m maa intraperitoneally

o       ESOPHAGEAL TRANSIT (done for reflux)

       Tc99m-sulfur or albumin colloid

       Oral, 0.15-0.30mCi;

       Igestion-to-imaging:immediate

       NPO=4-6hrs

       Normal, 90% activity should have transferred esophagus in 15sec.

o       GERD (kids)

       Tc99m sulfur or albumin colloid; 140keV, T1/2=6hrs.

       Oral in 150cc of orange juice mixed with 150cc of 0.1N HCl; 0.3mCi, Imm

       More than 4% of gastric activity back in esophagus is abnormal.

q  GU

o       Tc-99m DTPA � Dose - 20 mCi

       Critical organ = bladder

o       Tc-99m MAG3 (mercaptylacetyltriglycine) Dose - 8 mCi

       Critical organ = bladder

o       Tc-99m DMSA (dimercaptosuccinic acid) Tubular agent

       Critical organ = kidney

o       Lasix (routine is 40mg IV)

o       enalaprilat (40 ug/kg, maximum of 2.5 mg)

o       RADIONUCLIDE CYSTOGRAM

       Tc99m pertechnetate(prefer)

       Tc99m-sulfur colloid/DTPA

       Can also be used.

       Sterile urethral catheterization.0.5-1.0mCi mixed with 250-300cc of saline

       Used in pediatric as VCUG, less radiation.

o       TESTICULAR SCAN

       Tc99m pertechnitate/DTPA

       IV, 30mCi; Inj-to-imaging: immediate

       Delay in 15min.

q  Thyroid imaging

o       Iodine-123

       decays by electron capture,

       Gamma energy of 159 keV.

       Dose -200-400 uCi

       Critical organ = thyroid

o       Iodine -131 .

       Critical organ = thyroid

       Dose

o   Diagnostic: 2-5 mCi po for whole body for following a patient with thyroid carcinoma.
Therapeutic: 80-150 uCi per gram of thyroid tissue for Graves' disease

o   100-200 mCi for thyroid carcinoma ablation in thyroid neoplasm

o       Technetium-99m Pertechnetate

       Dose - 3 mCi intravenously

o       % Uptake = (normal = 10 - 30 %).

q  Parathyroid

o       Tc99m Sestamibi

       Dose 20 mCi

       Image at 15 min and 2 hrs

q  CNS

o       Tc99m-HMPAO (Hexamethylpropylenamine oxime): Ceretec

       Dose � 20 mCi - Flow study

o       CISTERNOGRAM

       In111-DTPA - Spinal injection, 0.5mCi

q  LYMPHOSCINTIGRAPHY

       Filtered Tc99m sulfur colloid

       Intradermal or peritumoral 4-8 injections within 1cm of biopsy/tum.

       0.1mCi, immediate


Dose 5 mCi

o       Technetium-99m Pertechnetate(thyroid) - 3 mCi

o       Iodine -131 - 2-5mCi

o       Choletec � 5 mCi

o       MAA � 5 mCi for VQ and Denver shunt

o       Gallium 67 � 5 mCi for infection

q  Dose 10 mCi

o       Octreotide � 6 mCi

o       Tc-99m MAG3 (mercaptylacetyltriglycine) - 8 mCi

o       Sulfer Colloid (GI bleed) - 10 mCi

o       Technetium -99m HMPAO - Labeled Leukocytes - 10 mCi

o       MIBG - 10 mCi

o       Gallium 67 � 10 mCi for Tumor

q  Dose 20+ mCi

o       Techneium 99m MDP - 15-25 mCi

o       Tc99m Sestamibi - 20 mCi

o       Tc99m-HMPAO CNS - 20 mCi

o       Tc-99m DTPA GU � ��20m

o       Tc-99m Tagged Red Blood cells - 20 mCi

o       Tc-99m DTPA - 20-30 mCi Aerosol -1 MCi (reaches lungs)

o       Tc99m pertechnitate/DTPA (Testicle) -30mCi

q  Other

o       Iodine-123- 200-400 uCi

o       Indium -111 Labeled Leukocytes - 500 uCi in adults

o       In111-DTPA - Spinal injection, 0.5mCi