Mechanisms of Localization:

Cell Sequestration

•  MECHANISM: CELL SEQUESTRATION

   

  • Spleen only imaging involves radiolabeling and then heat damaging of patient's red cells to take advantage of the spleen's normal function, i.e., removal of damaged red cells. This procedure permits visualization of the spleen with minimal or no visualization of the liver. Rarely performed, but considered a classical mechanism of localization of radiopharmaceuticals.

   

  • Radiopharmaceutical: Tc-99m damaged autologous red cells. Particle size: ~ 7 mm

   

  • Long t_biol; probably in the range of 10-20 hr.