SAP_scan
A SAP scan is a type of nuclear medicine imaging test which uses iodine-123 (123I) and serum amyloid P component (SAP) to diagnose amyloidosis.[1][2]
In patients with amyloidosis, large deposits of SAP coat the affected organs, in addition to the low levels normally found in the blood stream.[3] The injected 123I-SAP localises specifically to amyloid deposits, showing up as hot spots in the image.[4]