Abdominal Radiology

, Volume 43, Issue 3, pp 554–565 | Cite as

Extracolonic findings and radiation at CT colonography: what the referring provider needs to know



A better understanding of the risks and benefits of extracolonic findings and radiation dose will aid in the safe and proper implementation of CT colonography in clinical practice. The majority of extracolonic findings in screening patients are benign and can be ignored by referring physicians. Radiologists also need to be responsible in reporting extracolonic findings. Referring providers must be knowledgeable about the theoretic risks and controversies regarding the use of ionizing radiation. Screening CT colonography imparts a low-level of radiation to patients that is equivalent or less than annual background dose.


CT CT colonography Colorectal cancer Radiation dose Iterative reconstruction Extracolonic 


Compliance with ethical standards


No funding was provided for this manuscript.

Conflict of interest

Judy Yee, MD, FACR has received research Grants from Echopixel and Philips. Elizabeth McFarland, MD is a member of the Medical Advisory Board for Vital Images.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.

Informed consent

For this type of study, formal consent is not required.


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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Radiology, Albert Einstein College of MedicineMontefiore Medical CenterBronxUSA
  2. 2.SSM St. Joseph Health CenterSt. CharlesUSA

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