Patients Receiving Over 100 mSv as Cumulative Effective Dose from Recurrent CT Exams

CT dose for a defined level of diagnostic information has gone down substantially. There has been a common feeling that CT is now a low dose imaging modality. A large number of publications have assessed how a different technology or technique has helped to reduce the dose in a single CT exam to maintain same level of noise in the image or how and how much dose reduction could be achieved without affecting the diagnostic information.

Even with all these efforts, there remains a lack of information characterizing the patients who receive the highest cumulative doses from recurring CT exams. There has been little attention paid to know if a sizable number of patients in population receive cumulative effective dose (CED) of 100 mSv or more from CT exams alone. Further, it has also not been known if a significant number of patients in this dose range are in age bracket (0 to 50 years) where the radiation effects can be of concern and what is the level justified imaging in this group.

To answer all the above questions, the MGH started a multi-centric study initially in the USA and then extended to other countries through International Atomic Energy Agency (IAEA). The publications below may be referred to for details: