Contrast media injectors are part of the medical equipment used to deliver fluids in examinations such as CT, MRI, fluoroscopy and angiography. Many of these diagnostic imaging procedures include the administration of intravenous contrast agents to enhance the blood and perfusion in tissues.

Mainly there are two types of injector technology:
See also Single-Head Contrast Media Injector, Dual-Head CT Power Injector, Syringeless CT Power Injector.

The use of x-ray contrast agents in computed tomography (CT) began with a hand injection by the radiologist in the scan room. During its history, CT scanners have made great improvements in speed and image quality. Actual CT systems with multiple detectors allow scan times of a few seconds per body region. Some CT protocols require multiphase scans, where a body region is imaged with a single bolus of contrast in different blood flow phases. Automatic power (pressure) contrast media injectors are required to provide precise control of flow rate, volume and timing of injection. The use of a saline bolus following contrast administration reduces the volume of contrast required.

Most relevant topics for the use of a power injector in medical imaging procedures such as contrast enhanced computed tomography (CECT):
Must have basic injector control options:
Examples of other injector control options:

Single-head contrast media injectors ('contrast only') have been first developed in the 1970s. The construction consists of a syringe with the contrast medium inserted into the injector head and a plunger to deliver the contrast medium from the syringe via tubing connected to the patient.
Injectors used in cath lab angiography are often single-head injectors using one syringe.
Angiography contrast delivery systems inject contrast agent into arteries, where air embolisms can present a serious risk. For that reason, cath lab pressure injectors should have air embolism detectors, warning of bubbles in the line before they reach a patient. Air embolisms are not a major issue for CT scans, due to the venous access any small bubbles injected into a vein are expelled through the lungs. Procedures in the interventional suite need low, variable flow rate injections.

See also Contrast Media Injector, Dual-Head CT Power Injector, CT Power Injector, Multi-Head Contrast Media Injector, Syringeless CT Power Injector.

Biliscopin® Infusion, an iodinated contrast medium for intravenous cholecystography is secreted actively by the hepatocytes. The biliary excretion rate of a biliary contrast medium is determined by the binding to plasma proteins and liver receptor proteins, and by its transport maximum for the liver. Because of its high hepatocellular transport rate, Biliscopin® Infusion leads rapidly to high grade contrast density in the intra-hepatic and extra-hepatic biliary ducts as well as in the gallbladder.
Computed tomography with biliary contrast agents provides maximum quality preoperative imaging of the biliary tract.

Cholografin® Meglumine is a contrast agent for intravenous cholangiography and cholecystography. Iodipamide's primary excretion through the hepato-biliary system and concentration in bile allows visualization of the gallbladder and biliary ducts.

Conray® is a contrast agent intended for intravascular administration as a diagnostic radiopaque medium. Conray® is rapidly transported through the circulatory system to the kidneys and is excreted unchanged in the urine by glomerular filtration.
See also Ionic Contrast Agents, Contrast Media Injector, Dual-Head CT Power Injector, CT Power Injector.