Radiologic imaging in cystic fibrosis: cumulative effective dose and changing trends over 2 decades.
OBJECTIVE
With the increasing life expectancy for patients with cystic fibrosis (CF), and a known predisposition to certain cancers, cumulative radiation exposure from radiologic imaging is of increasing significance. This study explores the estimated cumulative effective radiation dose over a 17-year period from radiologic procedures and changing trends of imaging modalities over this period.


METHODS
Estimated cumulative effective dose (CED) from all thoracic and extrathoracic imaging modalities and interventional radiology procedures for both adult and pediatric patients with CF, exclusively attending a nationally designated CF center between 1992-2009 for > 1 year, was determined. The study period was divided into three equal tertiles, and estimated CED attributable to all radiologic procedures was estimated for each tertile.


RESULTS
Two hundred thirty patients met inclusion criteria (2,240 person-years of follow-up; 5,596 radiologic procedures). CED was > 75 mSv for one patient (0.43%), 36 patients (15.6%) had a CED between 20 and 75 mSv, 56 patients (24.3%) had a CED between 5 and 20 mSv, and in 138 patients (60%) the CED was estimated to be between 0 and 5 mSv over the study period. The mean annual CED per patient increased consecutively from 0.39 mSv/y to 0.47 mSv/y to 1.67 mSv/y over the tertiles one to three of the study period, respectively (P < .001). Thoracic imaging accounted for 46.9% of the total CED and abdominopelvic imaging accounted for 42.9% of the CED, respectively. There was an associated 5.9-fold increase in the use of all CT scanning per patient (P < .001).


CONCLUSIONS
This study highlights the increasing exposure to ionizing radiation to patients with CF as a result of diagnostic imaging, primarily attributable to CT scanning. Increased awareness of CED and strategies to reduce this exposure are needed.
Cork Cystic Fibrosis Center, Cork University Hospital, University College Cork, Cork, Ireland.
Oisin J
OJ
O'Connell
Cork Cystic Fibrosis Center, Cork University Hospital, University College Cork, Cork, Ireland.
Sebastian
S
McWilliams
Department of Radiation Physics, Cork University Hospital, University College Cork, Cork, Ireland.
AnneMarie
A
McGarrigle
Department of Radiology, Cork University Hospital, University College Cork, Cork, Ireland.
Owen J
OJ
O'Connor
Department of Medicine, Cork University Hospital, University College Cork, Cork, Ireland.
Fergus
F
Shanahan
Cork Cystic Fibrosis Center, Cork University Hospital, University College Cork, Cork, Ireland.
David
D
Mullane
Department of Renal Medicine, Cork University Hospital, University College Cork, Cork, Ireland.
Joseph
J
Eustace
Department of Radiology, Cork University Hospital, University College Cork, Cork, Ireland.
Michael M
MM
Maher
Cork Cystic Fibrosis Center, Cork University Hospital, University College Cork, Cork, Ireland. Electronic address: Barry.Plant@hse.ie.
Barry J
BJ
Plant
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000000981:diagnostic imaging*; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D007223:Infant; D008297:Male; D009010:Monte Carlo Method; D009683:Nuclear Medicine; D010641:Phenotype; D011829:Radiation Dosage; D011860:Radiography, Abdominal; D015641:Radiography, Interventional; D013902:Radiography, Thoracic; D011874:Radiometry / Q000379:methods*; D011877:Radionuclide Imaging; D012307:Risk Factors; D014057:Tomography, X-Ray Computed