M . EL Fahssi et al .: Radioprotection 2024 , 59 ( 1 ), 13 – 18 15
Table 3 . The mean of CTDIvol , DLP , and effective dose for Brain C� , Chest C� and CAP Cþ .
Brain C�
Chest C�
Parameters |
Mean |
Range |
SD |
Mean |
Range |
SD |
Mean |
Range |
SD |
CTDI vol |
53,80 |
20,73 – 78,04 |
14,43 |
9,64 |
5,48 – 15,83 |
3.29 |
7,17 |
4,55 – 10,33 |
1.80 |
DLP |
1131,44 |
607,07 – 1669,28 |
339,60 |
367,15 |
205,35 – 643,10 |
137.6 |
465,73 |
219,09 – 666,49 |
128.94 |
Effective dose |
2,37 |
1,27 – 3,50 |
0,71 |
6,50 |
3,63 – 11,38 |
2.43 |
7,13 |
3,29 – 10,00 |
1.93 |
CAP Cþ
Table 4 . The mean of CTDIvol , DLP , and effective dose for Abdomen C� , Abdomen Cþ , and AP Cþ .
Abdomen C� |
Abdomen Cþ |
AP |
|
|
Cþ |
Parameters |
Mean |
Range |
SD |
Mean |
Range |
SD |
Mean |
Range |
SD |
CTDI vol |
7,25 |
2,26 – 12,81 |
2.68 |
7,99 |
4,06 – 10,63 |
2.68 |
6,31 |
2,26 – 9,96 |
1.98 |
DLP |
405,11 |
99,04 – 748,14 |
171.18 |
438,95 |
215,37 – 614,68 |
171.18 |
314,45 |
75,6 – 627,2 |
132.95 |
Effective dose |
6,24 |
1,53 – 11,52 |
2.64 |
6,76 |
3,32 – 9,47 |
2.57 |
5,07 |
1,16 – 9,66 |
2.05 |
Fig . 1 . Distribution of CTDvol values during brain CT examinations . Fig . 2 . Distribution of DLP values during brain CT examinations .
CT-exams . The slice thickness is equal to 1,25 for all CTexams .
Tables 3 and 4 show that the mean CTDI vol varies from 6,31 mGy for AP with contrast media to 53,80 mGy for brain without contrast media . The mean DLP varies from 314,45 mGy . cm for AP with contrast media to 1131,44 mGy . cm for the brain without contrast media . The mean effective dose varied from 2,37 mSv for the brain without contrast media to 7,13 mSv for CAP with contrast media .
According to Figures 1 and 2 the CTDIvol values for brain CT vary from 20.73 to 78.04 mGy with a mean value of 53.80 mGy . DLP values vary from 607.07 to 1669.28 mGy . cm with a mean value of 1131.44 mGy . cm .
Table 5 shows that the DRL in terms of CTDI vol varies from 8,14 mGy for AP with contrast media to 64,45 mGy for the brain without contrast media . The DRL in terms of DLP varies from 417 mGy . cm for the chest without contrast media to 1405,77 for the brain without contrast media .
Table 6 shows that there was no association between patient gender and effective dose for all CT examinations . However , there is an association between patient age and the effective dose for brain CT without contrast media and chest CT without contrast media . In addition , there was an association between BMI and the effective dose of AP CT with contrast media and CAP CT with contrast media .
4 Discussion
The results show that , in terms of exposure parameters , the tube voltage is invariable for all examinations with a fixed value of 120 kV . In addition , the voltage does not change according to whether or not a contrast media is administered .