C-arm portable fluoroscopy is suitable for external biliary drainage procedures. This fluoroscopy machine consists of a 23-cm-diameter image intensifier, which is amended between the gantry and table socket of a CT fluoroscopy scanner. Placement of the C-arm allows performance of fluoroscopy on the CT table when the patient is moved out of the gantry.

C-peptide is a subunit of the hormone insulin. It is a blood test that measures the amount of C-peptide. It is measured to differentiate insulin produced by the body from insulin injected into the body. When insulin is synthesized by the beta cells of the pancreas, it is produced as a large molecule (a propeptide). This molecule is then split into two pieces: insulin and C-peptide. The function of C-peptide is not known. The C-peptide level may be measured in a patient with type 1 diabetes to see if any insulin is still being produced by the body.

C-reactive protein (CRP) is a test that measures the amount of a protein in the blood that signals acute inflammation. C-reactive protein is produced by the liver. The level of CRP rises when there is body-wide (systemic) inflammation. The CRP test is considered a general test, not a specific one. In other words, it can reveal that there is inflammation present in the body.

C-Reactive Protein is used as an in vitro diagnostic marker to aid in the evaluation of the amount of injury to human body tissue. CRP is also useful as a prognostic indicator for the risk of cardiovascular disease.

The CO 2 skin resurfacing laser system produces an intense beam of light of a specific, known wavelength. There are two types of lasers produce light that is well absorbed by the upper to middle layers of the skin, light produced from carbon dioxide gas (CO 2 ) and light produced from a crystal made of erbium, yttrium, aluminum, and garnet (Er:YAG). Combination lasers are also commercially available. Before the procedure begins, medication is often given to relax the patient and reduce pain. For small areas, local topical anesthetics are often used to numb the area to be treated. Alternatively, for large areas, nerve block-type anesthesia is used. During the procedure, the patient lies on his or her back on the surgical table, eyes covered to protect them from the laser light. Laser passes are performed over the area being treated, utilizing computer control of the laser for precise results. The laser skin resurfacing is used on the face, as elsewhere the healing process may be so slow as to result in scarring.