Method Of Localization of NM Rphxs 2024 Flashcards
Compartmental
-Compartmentalized or compartment localization.
-Molecules of interest distributed in an enclosed volume.
-Volume is enclosed in a compartment.
Tc-99m sestamibi and Tc-99m tetrofosmin cross cell membranes by lipophilic diffusion
Passive diffusion
Passive diffusion
described as a random movement of molecules looking to achieve a uniform concentration
Tc-99m Exametazime (HMPAO) and Tc-99m bicisate (ECD)
Passive diffusion
Cerebrospinal fluid- Cisternogram (In-111 DTPA)
Compartmental Localization
TC-99m DTPA brain imaging
Passive diffusion
Blood pool- MUGA and GI bleed (Tc99m RBCs)
Compartmental
Secretion of certain substances by the kidney tubular cells into the urine (Tc99m mertiatide for tubule secretion renal imaging)
Secretion
Filtration
Transit of molecules through pores (think filters)
Glomerular Filtration by kidney for glomerular function renal imaging using Tc-99m DTPA
Filtration
I-123 and I131 elevate thyroid function, trapped and organified by
Acrive Transport
Rb-82 used in PET myocardial perfusion scans
Active Transport
Na+/K+ pump, cardiac imaging using Thallous Chloride Tl-201
Active Transport
Lung airways- vent studies (Xe-133)
Compartmental
Tc-99m pertechnetate (TcO4-) for thyroid imaging
Active Transport
Facilitated Diffusion
Carrier-mediated transport across membranes. Prime example is glucose
gastrointestinal tract- Gastric emptying (Tc99m SC)
compartmental
secretion of certain substances by the liver in the bile (Tc99m mebrofenin for hepatobiliary imaging)
Secretion
peritoneal cavity- Leveen shunt study (Tc99m SC or MAA)
compartmental
F-18 FDG enters cells via glucose transporters and is used for PET WB imaging and epilepsy
Facilitated Diffusion
Facilitated
Diffusion
Glucose
Active transport
Carrier-mediated transport across membranes. Uses normal operative metabolic pathways in the body. Moves radiopharmaceuticals across cell membranes and into cells.
Tc-99m succimer (DMSA)
Active Transport
Cell sequestration
process where old or damaged RBCs are removed from the circulation
Secretion
Special case of active transport out of glands and other tissues
I-123 MIBG for neuroendocrine tumors
Active Transport
secretion of hydrochloric acid by the stomach (TcO4-) used for Meckels diverticulum imaging
Secretion
Spleen tissue imaging using Tc99m heat damaged RBCs
Cell sequestration
capillary Blockade
Refers to micro-embolization (physical trapping) of particles in capillaries and pre-capillary arterioles
Tc99m MAA lung perfusion imaging
Capillary blockade
