Traditional Culture Encyclopedia - Photography and portraiture - When using contrast agent photography, the requirements for contrast agent are correct

When using contrast agent photography, the requirements for contrast agent are correct

When using contrast agent photography, the requirements for contrast agent are correct: good contrast, easy excretion and high price.

contrast media is a chemical injected (or taken) into human tissues or organs to enhance the image observation effect. The density of these products is higher or lower than the surrounding tissues, and the contrast is displayed by some instruments. Such as iodine preparation and barium sulfate commonly used in X-ray observation.

Contrast agent is one of the most commonly used drugs in interventional radiology, which is mainly used to display blood vessels and body cavities. There are many kinds of contrast agents, and most of the contrast agents used in interventional radiology are iodine-containing preparations. Since the first femoral artery angiography was successfully performed in the United States in 1924 with 5% sodium iodide, as with the development of interventional radiology, the contrast agent products have been constantly updated.

The dosage of contrast media is an independent risk factor for contrast media nephropathy. Cigarroa et al. proposed a formula for calculating the dosage of contrast agent: 5ml× body weight (Kg)/Cr(mg/dl), and the maximum dosage should not exceed 3 ml. Studies have shown that the incidence of contrast nephropathy is 21%-37% when the threshold dose is exceeded, and %-2% when the threshold dose is not exceeded.

After using the contrast agent, the patient should be kept for observation for at least 3 minutes, because 9% of the side effects occur during this period. High-risk patients should be kept under observation for a longer time. Delayed reactions (abnormal skin changes and cardiovascular system disorders) may still occur in rare cases. If the symptoms are serious, they should be observed and treated in intensive care.