A Study, Called UV Population, to Learn More About the Safety of the Study Drug Ultravist, Which is Given to Get Clearer X-ray Pictures, in People of Different Sexes, Races, and From Different Countries/Regions

This is an observational study in which patient data from the past of people who received Ultravist prior to an X-ray based scan are studied.

In observational studies, only observations are made without specified advice or interventions.

X-ray based imaging like computed tomography or angiography is used to make pictures of the structures inside the body. These pictures are needed in various medical situations. In some X-ray tests, the patient is given a compound called "contrast agent" that is injected into the vein. It helps to create clearer pictures as it makes internal body structures easier to see. With such contrast-enhanced imaging techniques, doctors can better see certain problems.

Ultravist is an iodine-based contrast agent. It is also called iopromide, and it is available for doctors to give patients before they have X-ray based scans.

Clinical studies on the overall safety of Ultravist have shown that hypersensitivity reactions (HSRs) may rarely occur. HSRs are undesirable reactions of the body's defense system (immune system) to the study drug. However, more information on HSRs is needed.

The main aim of this study is to find out whether certain groups of people are more likely to have HSRs after Ultravist injection than others (e.g., depending on gender, race, or country/region).

To do this, researchers will collect data from people with HSRs (all ages) after contrast-enhanced X-ray scans with Ultravist. These data come from four observational studies that have already been completed. Participants who had HSRs will be compared with participants in these studies who had no medical problems after receiving Ultravist to learn more about the characteristics of people at higher risk.

Data will be from the year 1999 up to 2011. No visits or tests are required as part of this study.