To: Dr. Madan Rehani
Chair, ICRP Document: Radiological Protection in the Use of Cone Beam Computed Tomography (CBCT)
Subject: Public Comments on Draft Report
Date: 9/19/2014
Dear Dr. Rehani:
On behalf of the Alliance for Radiation Safety in Pediatric Imaging, we would like to thank you and your committee for this welcome scientific report in the era of rapid growth of CBCT, particularly within the dental community. The Alliance shares the committee’s plea for caution in the need for justification and judicious use of this imaging modality in children, a most radiosensitive population. In fact, the timing of this publication coincides with the launch of the “IMAGE GENTLY IN DENTISTRY” campaign. This campaign seeks to raise awareness on the need for radiation protection for children in dentistry and is in part focused on the expanded role that CBCT is now playing worldwide in pediatric patient dental care. We would like to highlight several sections of the report that we particularly agree with and compliments the message of our new campaign:
- Line 363 Dental CBCT scans should be justified considering two dimensional radiography as an alternative and optimized through the use of small FOV and application and patient specific exposure factors. WE AGREE.
- Line 370 All personnel intending to use CBCT for diagnostic purposes should be trained in the same manner as diagnostic CT. WE AGREE.
- Line 375 We encourage local DRL as well as the establishment of national and international DRL.THE ESTABHMENT OF DRL IS IN ITS INFANCY AND THE EMPHASIS ON THE NEED FOR DRL IS MOST WELCOME.
- Line 587 As standard dose metrics cannot be applied to CBCT, manufacturers are urged to standardize their approach. WHILE MANUFACTURERS HAVE DONE A LOT, A CO-ORDINATED EFFORT IS REQUIRED.
- Line 771 There is “a substantial amount of information on dental CBCT by the European Commission SEDENTEXCT”. WE THANK THE EC FOR THIS INFORMATIVE DOCUMENT.
- Line 1145 Major international organizations share the belief that the risk of developing cancer in patients exposed to radiation from CT scans is very low but appears to be more than hypothetical. THIS IS A MOST IMPORTANT STATEMENT AS IT PROVIDES A LEVEL OF IMPORTANCE AND URGENCY TO THE WORK OF RADIATION PROTECTION IN CHILDREN.
- Line 1248 The ICRP concept of “as low as reasonably achievable” should be applied to achieve optimization within DRL. WE AGREE.
- Line 1280 This training should also be applied to non-imaging professionals who plan to use CBCT. TRAINING IN THE USE OF CBCT WITHIN THE DENTAL COMMUNITY IS A CHALLENGE THAT CAN BE MET THROUGH PROFESSIONAL SOCIETIES, AGENCIES AND INDUSTRY AND IS A CORE PRINCPLE OF RADIATION PROTECTION FOR CHILDREN.
- Line 1436 The issue of standardization in CBCT remains largely unresolved. AS STATED IN THE REPORT, THIS IS A SIGNIFICANT ISSUE.
- Line 1568 Know your equipment. THIS IS A KEY POINT OF THE IMAGE GENTLY IN DENTISTRY CAMPAIGN.
- Line 1577 Collimate THIS IS A KEY POINT OF THE IMAGE GENTLY IN DENTISTRY CAMPAIGN.
- Line 1882 Low dose scan protocols may be sufficient for high contrast structures such as the teeth THIS IS A KEY POINT OF THE IMAGE GENTLY IN DENTISTRY CAMPAIGN..
- Line 1886 There may be a dedicated section for paediatric protocols. We urge the committee to state “ There should be a dedicated section for paediatric protocols.
- Line 1982 Title “Children in CBCT”. Suggest changing the heading to “The Use of CBCT in Children”
- Line 2053 Lead aprons. SHIELDING IS A KEY POINT OF THE IMAGE GENTLY IN DENTISTRY CAMPAIGN.
- Line 2834 The smallest available volume size should always be chosen. THIS IS A KEY POINT OF THE IMAGE GENTLY IN DENTISTRY CAMPAIGN.
- Line 2856 The application of dental CBCT for paediatric patients is of particular concern due to their higher radiosensitivity. WE APPRECIATE THAT THIS COMMITTEE HAS EMPHASIZED THIS POINT.
- Line 3178 Level of training in radiological protection should be commensurate with the level of expected radiation exposure. WE AGREE.
- Line 3269 Training should be guided by the utility of information to the audience. WE AGREE.
- Line 3451 Expanded availability and newer applications have put CBCT technology in the hands of medical (ADD and dental) professionals who traditionally do not use CT. WE AGREE. THIS IS A PRIMARY DRIVER FOR THE IMAGE GENTLY IN DENTISTRY CAMPAIGN.
We thank the committee for allowing us the opportunity to comment on this document.
Attached are additional comments from individual members of the committee.
Sincerely,
Marilyn J. Goske MD Donald P. Frush, MD
Co-Chairs of the Alliance for Radiation Safety in Pediatric Imaging on behalf of the Steering Committee
Comments by Keith Strauss:
Radiological Protection in the Use of Cone Beam Computed Tomography (CBCT)
I would like to compliment the ICRP for putting together an important document that is clearly needed on the topic of CBCT. It does a nice job of describing the current state-of-the-art of CBCT.
However, the current use of CBCT too often is in the hands of operators who have not had the opportunity to gain an adequate knowledge of imaging physics and patient dose management to insure good patient care in all clinical settings. Since the authors of this report state that their purpose is to describe current state-of-the-art of CBCT, a description of a comprehensive, standardized QC program is not offered since some of the tools needed to achieve this are not currently agreed upon and developed.
Lines 1964 – 1981: While AEC adjusts the radiation exposure automatically on some units, this is not true for all CBCT units as noted in Line 1979. Guidance is needed for users of simpler CBCT units (manual operation only) when used for a range of body sizes.
Lines 3314 - 3342: The extent, scope, and quality of practiced Quality Control Programs for CBCT units is highly affected by the training and understanding of the importance of such programs by the end users. Since the operators of many CBCT units have little or no training in Image Quality and Radiation Dose Management, most operators will need considerable assistance to implement a quality QC program that is effective. In this spirit a more detailed description of a quality QC Program for CBCT is needed.