Eighty-three patients in childhood (39 male,
44 female; mean age: 13,49,
ranging between 2 and 17) who were admitted to our emergency department with trauma and underwent spine CT between January 2017- September 2018 were included in this study.
Patients were divided into three age groups: 0-7 (group 1),
7-14 (group 2) and 14-18 years (group 3).
There were 9 patients in group 1,
17 patients in group 2 and 57 patients in group 3.
In group 1,
thoracic spine CT was performed on 3 patients and thoracolumbar spine CT on 6 patients.
In group 2,
thoracic spine CT was performed on 1 patients,
thoracolumbar spine CT on 13 patients and lumbar spine CT on 3 patients.
In group 3,
thoracic spine CT was performed on 4 patients,
thoracolumbar spine CT on 31 patients and lumbar spine CT on 22 patients.
Table 1 shows the number of patients,
mean computed tomography dose index (CTDIvol) and dose-length product (DLP) values in thoracic,
thoracolumbar and lumbar spine CTs.
There were statistically significant differences between the CTDIvol and DLP values of thoracic spine CT examinations in group 1 and 3 (P: <0,001 and P: 0,022,
respectively),
thoracolumbar spine CT examinations in three groups (P: 0,006 and P: <0,001,
respectively) and lumbar spine CT examinations in group 2 and 3 (P: 0,012 and P: 0,010,
respectively) (Table 1).
Table 1.
Comparison between mean CTDIvol and DLP values of pediatric thoracic,
thoracolumbar,
lumbar spine CT examinations
Study
|
Group
|
N
|
CTDIvol
|
P
|
DLP
|
P
|
Thoracic
spine CT
|
Group 1
Group 2
Group 3
|
3
1
4
|
2,75
0,83
7,8
|
<0,001 (between group 1 and
3)
|
82
20
252,25
|
0,022 (between group 1 and
3)
|
Thoracolumbar spine CT
|
Group 1
Group 2
Group 3
|
6
13
31
|
4,51
6,55
8,23
|
0,006
|
174,56
348,23
514,13
|
<0,001
|
Lumbar
spine CT
|
Group 2
Group 3
|
3
22
|
2,65
8,08
|
0,012
|
66,85
280,19
|
0,010
|
The mean scan length of thoracic spine CT was 26.53 cm in group 1,
24.09 cm in group 2 and 34.98 cm in group 3.
The mean scan length of thoracolumbar spine CT was 38.11 cm in group 1,
51.77 cm in group 2 and 62.82 cm in group 3.
The mean scan length of lumbar spine CT was 26.45 cm in group 2 and 33.77 cm in group 3.
There was statistically significant difference between the scan length of thoracolumbar spine CT in three groups (P: 0,001) (Table 2).
Table 2.
Comparison between scan length of spine CT in different age groups
Study
|
Group
|
Scan length (cm)
|
P
|
Thoracic spine CT
|
Group 1
Group 2
Group 3
|
26,53
24,09
34,98
|
0,20
|
Thoracolumbar spine CT
|
Group 1
Group 2
Group 3
|
38,11
51,77
62,82
|
0,001
|
Lumbar spine CT
|
Group 2
Group 3
|
26,45
33,77
|
0,07
|
Spine CT examinations performed with high kV (110-130 kV) values caused higher CTDIvol and DLP values in thoracolumbar spine CT in group 2,
thoracolumbar and lumbar spine CT in group 3.
However,
there was no statistically significant difference between CTDIvol and DLP values of patients scanned with high kV and low (80 kV) kV used CT examinations in terms of CTDIvol and DLP values (P: >0,05) (Table 3).
Table 3. Mean CTDIvol and DLP values of spine CT examinations at different kV values (*)
Group
|
Study
|
kV
|
N
|
CTDIvol
|
P
|
DLP
|
P
|
Group 1
|
Thoracic spine CT
|
80
130
|
1
2
|
0,73
3,77
|
-
|
15
115,5
|
-
|
Thoracolumbar spine CT
|
110
120
130
|
3
1
2
|
4,13
10,04
2,33
|
0,304
|
168,12
360
91,5
|
0,304
|
Group 2
|
Thoracic spine CT
|
110
|
1
|
0,83
|
-
|
20
|
-
|
Thoracolumbar spine CT
|
80
110
120
130
|
1
9
1
2
|
1,13
6,60
7,5
8,33
|
0,263
|
37
371,02
348
390
|
0,434
|
Lumbar spine CT
|
80
110
130
|
1
1
1
|
1,99
2,18
3,8
|
-
|
50,5
74,07
76
|
-
|
Group 3
|
Thoracic spine CT
|
110
120
130
|
1
1
2
|
3,94
9,21
9,025
|
0,407
|
144
322
271,5
|
0,259
|
Thoracolumbar spine CT
|
110
120
130
|
12
5
14
|
7,29
7,75
9,21
|
0,393
|
499,30
559,41
510,68
|
0,813
|
Lumbar spine CT
|
110
120
130
|
3
6
13
|
4,93
8,42
8,66
|
0,085
|
148,98
291,47
305,27
|
0,096
|
*P values shown as (-) indicates absence of statistical comparison due to limited number of patients.
CTDIvol and DLP values of spine CT examinations increased as the collimated slice (CSL) values decreased.
There were significant differences between DLP values of thoracolumbar spine CTs acquired with CSL of 0.6 mm and 2.5 mm,
0.8 mm and 2.5 mm,
1.2 mm and 2.5 mm in group 3 (P: 0,007,
P: 0,003 and P: 0,001,
respectively).
CTDIvol values of thoracolumbar spine CTs acquired with 2.5 mm was significantly lower than CSL of 1.2 mm in group 3 (P: 0,003).
CTDIvol and DLP values of lumbar spine CT examinations acquired with CSL values of 2.5 mm were significantly lower than CSL of 1.2 mm in group 3 (P: 0,007 and P: 0,005,
respectively) (Table 4).
Table 4.
Mean CTDIvol and DLP values of pediatric spine CT examinations at different CSL values (*)
Group
|
Study
|
Collimated Slice (CSL) (mm)
|
N
|
CTDIvol
|
P
|
DLP
|
P
|
Group 1
|
Thoracic
spine CT
|
1,2
1,5
2,5
|
1
1
1
|
5,83
1,71
0,73
|
-
|
184
47
15
|
-
|
Thoracolumbar
spine CT
|
0,6
0,8
1,2
1,5
2,5
|
1
1
1
1
2
|
7,19
10,04
3,91
1,9
2,02
|
-
|
279,37
360
185,01
57
83
|
-
|
Group 2
|
Thoracic
spine CT
|
2,5
|
1
|
0,83
|
-
|
20
|
-
|
Thoracolumbar
spine CT
|
0,6
0,8
1,2
2,5
|
5
2
2
4
|
7,52
5,95
4,19
4,92
|
0,003
(between
0,6 and
2,5 mm)
|
456,89
275,5
235,82
229,5
|
0,004
(between
0,6 and
2,5 mm)
|
Lumbar
spine CT
|
0,6
1,2
2,5
|
1
1
1
|
2,18
1,99
3,8
|
-
|
74,07
50,5
76
|
-
|
Group 3
|
Thoracic
spine CT
|
0,8
2,5
|
2
2
|
6,57
9,02
|
-
|
233
271,5
|
-
|
Thoracolumbar
spine CT
|
0,6
0,8
1,2
2,5
|
4
5
14
8
|
11,86
7,75
8,96
5,46
|
0,003
(between
1,2 and
2,5 mm)
|
718,35
559,41
595,62
241,12
|
0,007; 0,003 and
0,001 (between 0,6-
2,5; 0,8-2,5 and 1,2-
2,5 mm respectively)
|
Lumbar
spine CT
|
0,8
1,2
1,5
2,5
|
5
12
1
4
|
9,09
9,21
5,04
4,2
|
0,007
(between
1,2 and
2,5 mm)
|
304,36
330,37
227
112,75
|
0,005
(between
1,2 and
2,5 mm)
|
*P values shown as (-) indicates absence of statistical comparison due to limited number of patients.
In 70 patients,
at least one plain radiography was taken before CT.
Fourteen patients (87,5%) with traumatic injury had spine plain radiography.
The incidence of traumatic injury in the plain radiography was 7 (10%) and the incidence of traumatic injury in the CT was 16 (19,27%) (Table 5).
Sensitivity values of plain radiography and spine CT in traumatic spine injury were 43% and 100%,
respectively.
Table 5.
Number of patients with traumatic injury in CT and plain radiography
Study
|
Traumatic injury
|
N
|
Radiography
|
Positive
Negative
Total
|
7
63
70
|
CT
|
Positive
Negative
Total
|
16
67
83
|