| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Letters to the Editor |
Department of Radiology, National Naval Medical Center, 8901 Wisconsin Avenue, Bethesda, MD 20889-5600. e-mail: dm72v@nih.gov
Editor:
I read with interest the article by Dr Perisinakis and colleagues and the accompanying editorial by Dr Seibert in the September 2004 issue of Radiology (1,2). The radiation doses observed by Dr Perisinakis and colleagues in 11 patients undergoing kyphoplasty can be compared with the doses reported in the Radiation Doses in Interventional Radiology Procedures (RAD-IR) study (3), which included data on 98 patients who underwent vertebroplasty. Those vertebroplasty procedures had a mean fluoroscopy time of 16.2 minutes, a mean cumulative dose of 1.3 Gy, and a mean dose-area product of 7800 cGy · cm2. (These data are summed values for both imaging planes in biplane interventional radiology suites.)
Data on peak skin dose were also available for 61 of these 98 procedures (62%). Mean peak skin dose was 684 mGy (4). In only one (2%) of 61 cases did the peak skin dose exceed 2 Gy (the peak skin dose was 2183 mGy), and in no case did it exceed 3 Gy, even though more than one level was treated at the same time during many of these procedures (4). Two grays is the generally accepted threshold dose for skin effects (5).
The RAD-IR data (3) tend to support the conclusion of Dr Perisinakis and colleagues that skin injuries are unlikely after kyphoplasty. There are several important caveats, however. First, investigators in the RAD-IR study evaluated dose from vertebroplasty, a less complex procedure than kyphoplasty. Second, all procedures included in the RAD-IR study were performed by board-certified radiologists who were fellowship trained in either interventional radiology or neuroradiology. All had received training in radiation safety as part of their radiology residency. Third, all procedures included in the RAD-IR study were performed in dedicated interventional radiology suites, with fixed single-plane or biplane equipment that incorporated modern dose-reduction technologies. Dose-saving pulsed fluoroscopy was used in 67 (68%) of the 98 procedures (3). If fluoroscopically guided procedures are performed by operators without training in radiation safety, or if dose-reduction technologies are not available or not employed, it is likely that patient doses will be higher.
Finally, the operators in the article by Dr Perisinakis and colleagues and in the RAD-IR study were aware that radiation dose data were being recorded for the procedures they performed. This operator awareness has been shown to reduce radiation dose (the Hawthorne effect) (6).
The evidence suggests that the doses observed by Dr Perisinakis and colleagues and in the RAD-IR study are best-case scenarios. To avoid exceeding these doses, it is essential to adhere to the recommendations given by Dr Siebert and Dr Perisinakis and colleagues regarding operator training, the use of dose-reduction technologies, equipment maintenance, and dose measurement (1,2). The Society of Interventional Radiology has issued a quality improvement guideline that recommends measuring and recording patient radiation dose in the medical record for all fluoroscopically guided interventions (7).
FOOTNOTES
The opinions expressed herein are those of the author and do not necessarily reflect those of the United States Navy, the Department of Defense, or the Department of Health and Human Services.
REFERENCES
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| RADIOLOGY | RADIOGRAPHICS | RSNA JOURNALS ONLINE |
