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Table 2. Acquisitions parameters and ours DRL CI of paediatric head CT scans by age group of children.
CI of the head CT
Tumor / Mass
Cellulite
Hydrocephalus
Convulsive Crisis
Trauma / Hemorrhage
Age group( Years)
Tube voltage( kV)
Tube charge( mAs)
Number of series
Explored length( cm)
Pitch Our study
Min-Mean-Max |
Min-Mean-Max |
Min-Mean-Max |
Min-Mean-Max |
Min-Max |
P75 |
|
|
|
|
|
CTDI vol |
|
|
|
|
|
( mGy) |
P75 DLP( mGy. cm)
1 – 5 |
110 – 110 – 110 |
53 – 129 – 160 |
1 – 1.6 – 4 |
21 – 54 – 84 |
0.5 – 0.8 |
22 |
1321 |
5 – 10 |
110 – 112 – 130 |
105 – 140 – 172 |
1 – 2.5 – 4 |
17 – 51 – 84 |
0.5 – 0.8 |
24 |
1328 |
10 – 15 |
110 – 113 – 130 |
112 – 144 – 171 |
1 – 2.5 – 5 |
20 – 53 – 91 |
0.5 – 0.8 |
26 |
1708 |
1 – 5 |
110 – 110 – 110 |
34 – 84 – 154 |
2 – 2.5 – 5 |
24 – 42 – 79 |
0.5 – 0.8 |
20 |
849 |
5 – 10 |
110 – 113 – 130 |
44 – 96 – 206 |
2 – 2.6 – 4 |
26 – 49 – 54 |
0.5 – 0.8 |
22 |
1247 |
10 – 15 |
110 – 119 – 130 |
45 – 104 – 161 |
1 – 2.5 – 4 |
20 – 47 – 90 |
0.5 – 0.8 |
29 |
1306 |
1 – 5 |
110 – 110 – 110 |
97 – 131 – 167 |
1 – 1-1 |
14 – 24 – 58 |
0.5 – 0.5 |
22 |
533 |
5 – 10 |
110 – 114 – 130 |
109 – 141 – 172 |
1 – 1.1 – 2 |
16 – 25 – 34 |
0.5 – 0.8 |
25 |
787 |
10 – 15 |
110 – 121 – 130 |
117 – 152 – 189 |
1 – 1-1 |
16 – 23 – 31 |
0.5 – 0.8 |
38 |
875 |
1 – 5 |
110 – 110 – 110 |
83 – 129 – 160 |
1 – 1-1 |
15 – 22 – 40 |
0.5 – 0.5 |
22 |
486 |
5 – 10 |
110 – 112 – 130 |
111 – 134 – 172 |
1 – 1.1 – 2 |
17 – 22 – 27 |
0.5 – 0.8 |
22 |
553 |
10 – 15 |
110 – 118 – 130 |
121 – 148 – 198 |
1 – 1-2 |
17 – 23 – 45 |
0.5 – 0.8 |
38 |
808 |
1 – 5 |
110 – 110 – 110 |
105 – 129 – 153 |
1 – 1-1 |
16 – 25 – 56 |
0.5 – 0.5 |
21 |
498 |
5 – 10 |
110 – 114 – 130 |
111 – 141 – 215 |
1 – 1-2 |
19 – 26 – 46 |
0.5 – 0.8 |
24 |
757 |
10 – 15 |
110 – 121 – 130 |
115 – 149 – 187 |
1 – 1-1 |
18 – 25 – 36 |
0.5 – 0.8 |
38 |
991 |
most protocols. The mean value of series per scan differs depending on the reason for the exam and specific circumstances. It is approximately 1 series for trauma, hydrocephalus, and convulsive crisis indications; between 1 and 2 series for bronchiectasis / bronchitis and abdominal pain; between 2 and 3 series for brain tumors, tumor control, cellulitis, and pneumonia; and between 3 and 4 series for other indications. The slice thickness is consistently set at 5 mm for all indications; however, the pitch increases throughout the series both with and without contrast injection to minimize examination time and ensure proper vessel opacification at the appropriate times. Tables 2 – 5 provides detailed information on the median values and DRL for CT exams based on age and clinical indication.
The third-quartile values of the CTDI vol( mGy) for the five CI of head studies were as follows: 22 mGy to 26 mGy, 20mGyto29mGy, 22mGyto38mGy, 22mGyto38mGy, and 21 mGy to 38 mGy, respectively. These measurements correspond to three groups of children who were examined. A similar trend was observed in chest CT studies. The CTDI vol values for these chest scans varied from 3.7 mGy to 5.1mGy, 3.8mGyto4.8mGy, and3.8mGyto5.8mGy. In the case of abdomen-pelvis CI studies, the CTDI vol values ranged from 5.1 mGy to 7.3 mGy, 4.6 mGy to 7.7 mGy, and 4.9 mGy to 8.1 mGy, respectively. For CAP CI examinations, CTDI vol values varied from 5.4 mGy to 7.8 mGy, 4.7 mGyto7.1mGy, and4.9mGyto7.6mGy, respectively. Itis importanttonotethatchildrenaged10to15yearsexhibited higher CTDI vol values due to the increased voltage and intensity used for this age group. Significant differences in the distributions of CTDI vol were observed among the five CI of head CT scans across all age groups of children( p < 0.01). However, for chest scans, CAP examinations, and abdomen-pelvis studies, no significant variations in CTDI vol basedonCIwerefound( p > 0.01).
Tables 2 – 5 present our estimated 75th percentiles for DRL CI for DLP measured in mGy. cm. For head CT indications, the DRL values range from 1321 mGy. cm to 1708 mGy. cm, 849 mGy. cm to 1306 mGy. cm, 533 mGy. cm to 875 mGy. cm, 486 mGy. cm to 808 mGy. cm, and 498 mGy. cm to 991 mGy. cm, respectively. In the case of chest CT indications, the DRL values vary from 119 mGy. cm to 238 mGy. cm, 193 mGy. cm to 351 mGy. cm, and 221 mGy. cm to 656 mGy. cm, respectively. For abdomen-pelvis exams, the DRL CI ranges from 316 mGy. cm to 623 mGy. cm, 586 mGy. cm to 1167 mGy. cm, and 788 mGy. cm to 1654 mGy. cm, respectively. The CAP CI tests indicated that the DRL results varied from 966 mGy. cm to 1738 mGy. cm, from 552 mGy. cm to 1417 mGy. cm, and from 471 mGy. cm to 1106 mGy. cm, respectively. Notably, we observed substantial variations( p < 0.01) in the distribution of DRL among the five CI categories for head CT. This analysis revealed that the DRL CI values for congenital malformations, adrenal neuroblastoma, and tumor extension were significantly higher( p < 0.01) compared to those for pneumonia, bronchiectasis / bronchitis, ileus, and abdominal pain across all groups of children examined.
4 Discussions
The head CT was the most frequently examined anatomical region in the mother and child hospital’ s CT unit, and head trauma was its main indication. This result is in line with previous studies by Joseph Zira( Joseph Zira et al., 2021) in Nigeria, Järvinen( Järvinen et al., 2015) in Finland, Granata( Granata et al., 2015) in Italy, Tchaou( Tchaou et al., 2016) in Togo, and Samuel( Samuel et al., 2021) in Cameroon. The 10-15 years-old age group of children received the maximum dose for all clinical indications established, as highlighted by Tchaou( Tchaou et al., 2016). The findings from Joseph Zira