Cumulative radiation dose in patients with hereditary hemorrhagic telangiectasia and pulmonary arteriovenous malformations.
OBJECTIVE
To determine the cumulative effective dose (CED) of radiation from medical imaging and intervention in patients with hereditary hemorrhagic telangiectasia (HHT) who have pulmonary arteriovenous malformations and to identify clinical factors associated with exposure to high levels of radiation.


METHODS
All patients with at least 1 pulmonary arteriovenous malformation were identified from the dedicated patient database of a tertiary HHT referral centre. Computerized imaging and electronic patient records were systematically examined to identify all imaging studies performed from 1989-2010. The effective dose was determined for each study, and CED was calculated retrospectively.


RESULTS
Among 246 patients (mean age, 53 years; 62.2% women) with a total of 2065 patient-years, 3309 procedures that involved ionizing radiation were performed. CED ranged from 0.2-307.6 mSv, with a mean of 51.7 mSv. CED exceeded 100 mSv in 26 patients (11%). Interventional procedures and computed tomography (CT) were the greatest contributors, which accounted for 51% and 46% of the total CED, respectively. Factors associated with high cumulative exposure were epistaxis (odds ratio 2.7 [95% confidence interval, 1.1-6.3]; P = .02), HHT-related gastrointestinal bleeding (odds ratio 2.0 [95% confidence interval, 1.0-3.8]; P = .04) and number of patient-years (P < .0001).


CONCLUSIONS
Patients with HHT are exposed to a significant cumulative radiation dose from diagnostic and therapeutic interventions. Identifiable subsets of patients are at increased risk. A proportion of patients receive doses at levels that are associated with harm. Imaging indications and doses should be optimized to reduce radiation exposure in this population.
Department of Medical Imaging, St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada. Electronic address: kate.hanneman@utoronto.ca.
Kate
K
Hanneman
Division of Respirology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada; Toronto Hereditary Hemorrhagic Telangiectasia Program, Division of Respirology, Department of Medicine, St Michael's Hospital, Toronto, Ontario, Canada; Keenan Research Centre and the Li Ka Shing Knowledge Institute, St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.
Marie E
ME
Faughnan
Department of Medical Imaging, St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.
Vikramaditya
V
Prabhudesai
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001165:Arteriovenous Malformations / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011651:Pulmonary Artery / Q000002:abnormalities*; D011667:Pulmonary Veins / Q000002:abnormalities*; D011829:Radiation Dosage; D012189:Retrospective Studies; D013683:Telangiectasia, Hereditary Hemorrhagic / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed
Arteriovenous malformations; Hereditary hemorrhagic; Ionizing; Multidetector computed tomography; Radiation; Radiation dosage; Telangiectasia