Radiation dose to patients and staff during angiography of the lower limbs. Derivation of local dose reference levels.
BACKGROUND
The Euratom directive 97/43 recommends the use of patient dose surveys in diagnostic radiology and the establishment of reference dose levels (DRLs).


OBJECTIVE
To perform measurements of the dose delivered during diagnostic angiography of the lower limbs using thermoluminescence dosimeters (TLDs), extraction of DRLs and estimation of the effective dose and radiation risk for this particular examination.


METHODS
Dose measurement was performed on 30 patients by using TLD sachets attached in 5 different positions not only on the patient, but also to the radiologist. All the appropriate factors were recorded. Measurement of the ESD was performed after each examination.


RESULTS
The mean entrance skin dose (ESD) was calculated to be 70.8, 67.7, 24.3, 18.4, 9.7 mGy at the level of aorta bifurcation, pelvis, femur, knees, and at feet, respectively. The average effective dose is 9.8 mSv with the radiation risks for fatal cancer to be 5.4 x 10(-4). The effective dose of the radiologist was calculated to be 0.023 mSv per procedure.


CONCLUSIONS
Radiation dose variation depends on the physical characteristics of the patient, on the procedure preferences by radiologists and the difficulties in conducting procedures. The main reason for the increased patient dose, compared to other studies, is the number of frames rather than the duration of fluoroscopy. For DSA of the lower limbs, the DRL was chosen to be an entrance skin dose of 96.4 mGy in the pelvic region. The dose to the radiologist is negligible.
Topaltzikis
T
T
Medical Physics Department, University Hospital of Larissa, P.O. Box 1425, Larissa 41110, Hellas, Greece.
Rountas
C
C
Moisidou
R
R
Fezoulidis
I
I
Kappas
C
C
Theodorou
K
K
D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography / Q000379:methods* / Q000592:standards*; D005471:Fluoroscopy / Q000379:methods; D006801:Humans; D035002:Lower Extremity / Q000528:radiation effects; D008875:Middle Aged; D016273:Occupational Exposure; D011871:Radiology / Q000379:methods; D011874:Radiometry / Q000379:methods*; D012016:Reference Values; D012306:Risk; D012867:Skin / Q000528:radiation effects; D013819:Thermoluminescent Dosimetry; D014965:X-Rays