Image Wisely is a joint initiative of the American College of Radiology, Radiological Society of North America, American Society of Radiological Technologists and American Association of Physicists in Medicine.

Case 1: CT Dose and Size-Specific Dose Estimate (SSDE)

Explains common CT dose terms along with their proper usage and limitations.

Authors: M. Supanich, M; D. Peck

Target Audience: Radiologists, radiologic technologists and medical physicists working with computed tomography

This educational activity is free.

Learning Objectives
Upon completion of this case, the participant will be able to:

  1. Understand how CTDI and DLP are used
  2. Understand the limitations in these values with different size patients
  3. Understand the method used to determine the Size Specific Dose Estimate (SSDE)
  4. Understand the limitations in the use of SSDE

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CE Credit Information

The American College of Radiology is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians.

The American College of Radiology designates this online activity for a maximum of 0.5 AMA PRA Category 1 Credit(s)™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

The American College of Radiology (ACR) is approved by the American Registry of Radiologic Technologists (ARRT) as a Recognized Continuing Education Evaluation Mechanism (RCEEM) to sponsor and/or review Continuing Education programs for Radiologic Technologists and Radiation Therapists.

The American College of Radiology designates this educational activity as meeting the criteria for up to 0.5 Category A Credit hour(s) of the ARRT.

This Image Wisely Radiation Safety Case has been approved by the Commission on Accreditation of Medical Physics Education Programs, Inc. (CAMPEP) for 0.5 MPCEC continuing education credit hours.

There is no charge to participate in this educational activity. For CE credit tracking and reporting, you will be redirected to the ACR website to log in or register and add the free module to your shopping cart for $0. Step-by-step instructions on accessing the case are available here. In order to successfully complete the activity, participants must complete an activity evaluation and claim credit commensurate with their participation in the activity. For information about the accreditation of this program, please contact the ACR at imagewisely@acr.org.

Image Wisely encourages practitioners to optimize the amount of radiation used in
medically necessary imaging studies and to eliminate unnecessary procedures

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