Card Set Information
characteristics of ideal RP
short T 1/2
no particle emission
high target / non target ratio
preferred mode of decay
mechanisms of localization
Phagocytosis, capillary blockade, active transport, simple diffusion, cell sequestration, compartmental localization, antigen antibody complex.
removal of forgein matter by physical entrapment.
Tc-99 S.C. RES
mechanical obstruction of capillaries or precapillaries arterioles in lung,
Cellular metabolism concentrates RP in organ or tissue.
123-I NaI for thyroid function/imaging
movement of RP from area of higher concentration to area of lower concentraion.
breakdown of BBB allows RP to penetrate brain in area of affected tissue.
Removal of old or damaged RBCs from circulation by spleen; uptake of WBCs in infection sites.
51-Cr RBCs taken up by spleen
111-In WBCs sites of infection.
introduction of RP into well-defined body compartment where it remains for and extended period.
-99m Tc DTPA aerosol, 133Xe technegas
Antigen-Antibody complex formation;
radiolabeled antibody binds to tumor associated antigen.
using tumor specific labeled antibodies to detect cancer of stage therapy.
Mechanisms affecting biodistribution;
For most of NM the circulatory system transports the RP via venous blood supply.
Removed from circulation ether by RES or lungs depending on size.
most RPs bind to plasma protiens ( Albumin in many cases) plasma clearance affected if bound tightly.
causing a secondary condition arising from treatment of a primary condition.
: iodine contrast media affecting uptake. BoNE: poor uptake due to iron overload.
-Desirable-> Renal imaging
: admin of furosmide to rule out mechanical obstruction, MPI admin of persantine to dialate heart vessels.
Clinical investigation of new drugs.. steps
eIND ( exploratory investigational new drug)
IND (investigational new drug) phase 1 -3
NDA (new drug application)
performed on animals to determine biodistribution, kinetics , toxicity, dose estimitates , lethal , sublethal
limited human exposure
no therapeutic of diagnostic intent
limitied duration of dose.
Phase 1 clinical study
pharmacology studies in normal volunteers to find normal biodistributions in humans.
Phase 2 clinical study
studies of patients with specific disease/condition
determine additional evidence of safety and inital evidence of diagnostic or therapeutic efficacy.
Phase 3 clinical study;
determine optimum dose
establish addional uses
all commercially distributed RPs must be approved through the FDA and be assigned an NDA number.
Phase 4 clinical study
Post Market Surveillance
cardio pulmonary decompression
-heart failure, type A
: expected , dose dependant. Type B; unexpected, hypersensitivity.
; unusual individual response
organ being imaged
organ or body part receiving most of radiatin dose.
organ or body part delivering radiaiton dose to target organ (can be target organ delivering dose to self)
quantity of radiation enegry deposited in an absorber per gram of absorber
1 rad = 100 ergs/gram
the total amount of energy deposited in a volume of tissue.
g.rad = absorbed dose x tissue mass (grams)
1 g.rad = 100ergs of energy deposited in a vol of tissue
the fraction of energy of radiation emitted from a source organ that is absorbed in a target organ.
DOT 1 (white)
at 3ft NDR
DOT II (yellow)
DOT III (yellow)
The transport index should have the...
name of isotopes being delivered and the amount of exposure reading at 1 meter
divide into charged particles when in a solution.
high osmolar contrast 1300-1600 mOsm/kg
do not divide into particles when in a solution.
no degradation in the blood stream.
low osmolar contrast 500 to 850 mOsm/kg
the concentration of molecular particles in the contrast agent solution.
All IV contrast has a osmolality.....
greeater than blood plasma. 285 mOsm/kg
so IV contrast is Hypertonic compared to blood plasma. causing movement of water from tissues into vascular space. dyhadrating the patient.