Wholebody examinations in PET/CT were performed on a sample of 368 patients,
203 males and 165 females.
Mean values,
standard deviation (SD),
minimum and maximum values of patient’s age,
weight,
height,
body mass index (BMI) administered activities,
CTDI_{vol} and DLP,
are presented in Table 1.
The mean,
median and 75th percentiles for CTDI_{vol} were 5.12 mGy,
4.59 mGy and 6.03 mGy,
respectively.
The mean value of activity was 355.05 MBq,
as well the median was 358.45 MBq.
The estimation of Pearson’s coefficient revealed a strong positive correlation between the following pair of parameters.
The Pearson’s coefficient (r) between BMI and CTDI_{vol} was estimated 0.84,
BMI and activity was 0.69,
CTDI_{vol} and activity was 0.65,
and CTDI_{vol} and BMI was 0.78.
800x600
Table 1. Mean values ± standard deviation (SD),
minimum and maximum values of patient’s age,
weight,
height,
BMI,
administered activity,
CTDI_{vol} and DLP.

Age (yrs) 
Weight (kg) 
Height (cm) 
BMI (kg/m^{2}) 
CTDI_{vol} (mGy) 
DLP (mGy*cm) 
Activity (MBq) 
Mean±SD 
59.36±15.57

74.67±16.19 
169.44±8.56 
26±4.98 
5.12±1.81 
460.11±199.19 
355.05±71.39 
MinMax 
1692 
38125 
145195 
1443 
3.2412.8 
113.931374.94 
152.1592.9 
75th percentiles 
 
 
 
 
6.03 
 
394.23 
Figure 1 illustrates the distribution of CTDI_{vol} values according to BMI of the patients.
Fig. 1: Distribution of CTDIvol values.
Figure 1: Distribution of CTDI_{vol} values.
Figures 2 and 3 display frequency histograms of CTDI_{vol} values for PET/CT whole body examinations (n=368) and the injected ^{18}FFDG activity,
respectively.
In both cases,
the distribution is skewed and asymmetric with a main peak,
tail and some extreme values.[5]
Fig. 2: Histogram of CTDIvol values for PET/CT whole body examinations.
Figure 2: Histogram of CTDI_{vol} values for PET/CT whole body examinations.
Fig. 3: Histogram of injected FDG activity.
Figure 3: Histogram of injected FDG activity.