Abstract
The present study used a digital angiography x-ray device to measure the space dose and exposure dose of patients and practitioners using x-ray tube shielding devices developed in our laboratory. The intent of the study was to reduce the space dose within the test room, and to reduce the exposure dose of patients and practitioners. The patient and practitioner exposure doses were measured in five configurations in a human body model. The glass dosimeter was placed on the eye lenses, thyroid glands, left shoulder, right shoulder, and gonads. The beam was collimated at full size and at a 48% reduction for a comparative analysis of the measurements. The space dose was measured with an ion chamber at distances of 50 cm, 100 cm, and 150 cm from the x-ray tube under the following conditions: no shielding device; a shielding device made of 3-mm-thick lead (Pb) [Pb 3 mm shield], and a shielding device made of 3-mm-thick Pb (outside) and 3-mm-thick aluminum (Al) (inside) [Pb 3 mm+Al 3 mm shield]. The absorbed dose was the lowest when the 3-mm-thick Pb+3-mm-thick Al shield was used. For measurements made with collimated beams with a 48% reduction, the dose was the lowest at 154 μGy when the 3-mm-thick Pb+3-mm-thick Al shield was used, and was 9 μGy lower than the measurements made with no shielding device. If the space dose can be reduced by 20% in all situations where the C-arm is employed by using the x-ray tube shielding devices developed in our laboratory, this is expected to play an important role in reducing the annual exposure dose for patients, practitioners, and assistants.
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Fig. 5.
Comparison of the absorbed dose of the full size & down-sized beam collimations in the phantom.
![pmp-27-241f5.tif](/upload/SynapseXML/2129pmp/thumb/pmp-27-241f5.gif)
Fig. 6.
Comparison of the absorbed doses of the lenses, thyroid, left, right shoulder, and gonads depending on the presence or absence of shielding.
![pmp-27-241f6.tif](/upload/SynapseXML/2129pmp/thumb/pmp-27-241f6.gif)
Table 1.
Space dose rate with or without a shielding device measured at 100 cm in an x-ray tube.
Device | (Mean) | (SD) | N | F | Post hoc test in ANOVA |
---|---|---|---|---|---|
Not used (a) | 1.04 | 0.15 | 18 | 7.464∗∗∗ | a>b∗ |
Pb 3 mm (b) | 0.88 | 0.17 | 18 | a>c∗∗ | |
Pb 3 mm+Al 3 mm (c) | 0.84 | 0.16 | 18 |
Table 2.
Analysis of absorbed dose difference between beam collimation size.
Size | (Mean) | (SD) | N | df | t |
---|---|---|---|---|---|
Full | 184.8 | 2.45 | 50 | 81.531 | 36.350∗∗∗ |
Down | 160.8 | 3.97 | 50 |
Table 3.
Difference in absorbed dose depending on the presence or absence of a shield in lens.
Device | (Mean) | (SD) | N | F | Post hoc test in ANOVA |
---|---|---|---|---|---|
No used (a) | 11.00 | .67 | 10 | 63.359∗∗∗ | a>b, c, d, e∗∗∗ |
Pb (b) | 7.60 | .52 | 10 | d>b, c∗ | |
Pb+Al (c) | 7.60 | .52 | 10 | e>b, c∗ | |
Pb+Al+Al 1 mm (d) | ) 8.50 | .53 | 10 | ||
Pb+Al+Al 2 mm (e) | 8.50 | .53 | 10 |