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Objective Quantitative imaging evaluation was performed on the liver and spleen system lesions of patients with Gaucher disease after treatment. in order to deepen the understanding of Gaucher disease. Methods From August 1999 to August 2018, we registered, examined and treated children with Gaucher disease, and conducted quantitative imaging research on 40 children with Gaucher disease who were intensively followed up in Beijing Children's hospital, Capital Medical University until August 2018. At the same time, 34 normal volunteers were matched. All subjects were scanned with magnetic resonance imaging(MRI). The fat fraction(FF), iron content(R2*), standard apparent diffusion coefficient(sADC), slow apparent diffusion coefficient(D), fast apparent diffusion coefficient(D*) and perfusion fraction(f)of the liver and spleen were measured. The quantitative parameter values measured by patients with Gaucher disease and normal subjects were statistically analyzed by independent sample t-tests. Results The results showed that there was no significant difference in FF, R2*, sADC, D, D*, f of the liver and spleen, and liver elasticity was also within the normal range. However, the volume of liver and spleen in patients was significantly different from that in normal subjects. Conclusions After treatment, the volume of the liver and spleen in patients with Gaucher disease is greater than that of normal people, but other quantitative parameters are within the normal range, indicating that long-term enzyme replacement therapy can delay the progress of liver and spleen diseases to a certain extent. Quantitative imaging has a certain value in the evaluation of Gaucher disease.
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Objective To explore the application of adaptive statistical iterative reconstruction (ASIR)scanning technique in low dose pediatric cervical CT, especially in reducing the radiation dose for thyroid. Methods We retrospectivly analyzed 140 pediatric cervical CT. 70 cases of group A scaned with ASIR technology and preseting noise index 12 HU in Discovery CT 750 HD (GE Healthcare), and 70 cases of group B scaned with filtered back projection (FBP) technology and preseting noise index 14 HU in VCT 64 (64 Lightspeed VCT, GE Healthcare). The other scan parameters were same in 2 groups. The distribution characteristics of gender and age were completely consistent between groups. The minimum current, the maximum current, the current of thyroid on CT images and CT dose volume index (CTDIvol), scanning length and dose length product (DLP) on dose reports were all recorded for each child. The noise values of CT images were measured. 4 scores standard was used to evaluate the subjective image quality. The data were analyzed with SPSS 13, Kappa method for the test of consistency and t test for the differences of the measured data. Excel was used for mapping. Results The minimum current, the maximum current, the average current, the current for thyroid of the two groups were respectively (26.8 ± 4.2), (43.2 ± 15.4)mA;(35.8±9.6),(41.8±13.6)mA;(34.6±8.6), (41.0±13.2)mA;(36.8±12.3), (44.7±21.0)mA. The CTDIvol, DLP and the scanning length of the two groups were respectively(1.3 ± 0.3), (1.8 ± 0.6)mGy;(29.0 ± 8.3), (40.3 ± 15.6) mGy·cm and(157.5±20.2), (157.6±21.8)cm. The average current, the thyroid current, CTDI and DLP in group A were 15.8%, 17.9%, 27.3%and 28.4%lower than those in group B (t=-5.50—-0.02, P<0.01). The subjective image quality scores of the two doctors were respectively 3.4 ± 0.9, 3.3 ± 1.0, they were highly consistent (Kappa=0.834, P<0.01). The objective image noise of cancellous bone and neck muscles were respectively (32.5 ± 5.3),(32.9 ± 5.1)HU and (9.2 ± 2.3), (9.1 ± 2.0)HU, there were not statistically difference between the two groups (t=-0.47—0.24, P<0.05). Conclusion Compared with FBP, low dose pediatric cervical CT with 30%ASIR could provide dose reduction for thyroid and the whole neck while maintaining diagnostically acceptable images .
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Objective To observe the difference between skeletal age of hand and wrist and chronological age and explore the reliability of CHN radiographic atlas method to assess the skeletal age of hand and wrist in children and adolescent.Methods Total 1397 healthy children (666 boys,731 girls;age range,1.0-18.0 years old) with hand and wrist injury from 2007 to 2011 were selected.Forty groups (n =20 for boys and girls,respectively) were classified according to CHN radiographic atlas method.The radiographs of hand and wrist were assessed by CHN radiographic atlas method,the relations between skeletal age and chronological age were investigated by using Wilcoxon signed ranks test.Results According to the CHN radiographic atlas method,the difference in 1.0 to 3.9 years old,7.0 to 7.9 years old and 9.0 to 15.9 years old boy groups between skeletal age and the chronological age had statistical significance (P ＜0.05) ; the difference in 1.0 to 2.9 years old,8.0 to 11.9 years old,12.6 to 14.9 years old,and 17.0 to 18.0 years old girl groups between skeletal age and the chronological age had statistical significance (P ＜ 0.05).Besides,these skeletal age was higher than the chronological age.Conclusions Skeletal age assessed by the CHN radiographic atlas method in a majority of age groups was higher than chronological age.It should be cautious to estimate the contemporary Chinese children skeletal age of hand and wrist when using the CHN radiographic atlas method.