Technetium exametazime (trade name Ceretec) is a drug used for the detection of altered regional cerebral perfusion in stroke

Stroke

A stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...

 and other cerebrovascular diseases, and for the labelling of leukocytes to localise intra-abdominal infections and inflammatory bowel disease

Inflammatory bowel disease

In medicine, inflammatory bowel disease is a group of inflammatory conditions of the colon and small intestine. The major types of IBD are Crohn's disease and ulcerative colitis.-Classification:...

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Chemistry

The drug consists of two of the three stereoisomers of hexametazime (HMPAO), one of which is shown here, the other being its enantiomer

Enantiomer

In chemistry, an enantiomer is one of two stereoisomers that are mirror images of each other that are non-superposable , much as one's left and right hands are the same except for opposite orientation. It can be clearly understood if you try to place your hands one over the other without...

. The third stereoisomer is the meso form. Exametazime acts as a chelating agent for the radioisotope technetium-99m

Technetium-99m

Technetium-99m is a metastable nuclear isomer of technetium-99, symbolized as 99mTc. The "m" indicates that this is a metastable nuclear isomer, i.e., that its half-life of 6 hours is considerably longer than most nuclear isomers that undergo gamma decay...

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