Objective To investigate the value of spiral CT for the diagnosis and treatment of congenital anorectal malformations (CARM). Methods Thirty children with CARM underwent lateral upside-down plain film in abdomen and spiral CT scanning in pelvic cavity before surgical operation. The distance between rectal blind end and anal fossa in two imaging modalities was measured. The correlation between the measurement results in two imaging modalities was compared with operational results. Sacral deformation was diagnosed according to 3D reconstruction of CT images. Results The measurement results obtained from CT were correlated positively with those of operation (r=0.99, P<0.01). CARM combined with curved sacrum was diagnosed in one child. No correlation was found between the measurement results of X-ray and operation (r=0.31, P>0.05). Conclusion Spiral CT scanning can accurately describe the atresic level of rectum and malformation of sacrum. It can provide reliable evidence for surgeon to choose the best surgical method and to judge prognosis.

Objective To discuss the image characteristics of enlarged prostatic utricle in children.Methods 13 children with enlarged prostatic utricle were retrospectively analyzed,6 of whom checked by voiding cystic urethrography (VCUG),5 of whom by MRI,2 of whom by both VCUG and MRI.Results 8 cases with VCUG showed round-like or long circle utricle filled with contrast media located in the rear posterior urethra.Among them,3 cases showed the tubiform between utricle and posterior urethra.The other 5 cases displayed overlap between utricle and urethra,and there was no tubiform between utricle and posterior urethra.7 cases with MRI showed oblong cyst at the right rear middle of the bladder that showed low signal with T1 weighted image and high signal with T2 weighted image,crossing the center of prostate gland.Among them,5 cases showed the communication between oblong cyst and posterior urethra.Also,among them,5 cases were associated with the orchitis,epididymis phlogistic,scrotal phlogistic,and 1 case showed the right renal agenesis.Conclusion The VCUG and MRI are helpful to check enlarged prostatic utricle in children.They have different advantages in different aspect.

Objective To investigate the objective factors that affect the image quality of infant cranial CT using different mAs. Materials and Methods Ninety infants were divided into three groups randomly. The maximum anteroposterior diameter (MAPD) of skull of each infant was measured. Three reference levels, cerebellar, basal ganglia and centrum semiovale levels were selected respectively. Only one level was studied in each group and scanned with 150, 100 and 80 mAs. The subjective quality grade and the objective noise of all images were recorded and analysed statistically. Result The average MAPD of ninety patients was (148.0 ± 17.4)mm. On the cerebellar level, the subjective quality grade was lower than the other two levels, which were 6.3% , 9.4% and 22.9% respectively when mAs were 150, 100 and 80 mAs. Both quality grade of image and objective noise were significantly correlated with MAPD.Conclusion The inherent high noise of cerebellar level and MAPD were the objective factors that affect the image quality of low-dose cranial CT of infant.

Objective:To investigate the value of CT findings of childhood hepatoblastoma (HB) in predicting preoperative tumor risk stratification.Methods:Totally 46 children with HB confirmed by surgery and pathology were retrospectively enrolled from October 2010 to October 2019 in Shenzhen Children′s Hospital and Xuzhou Children′s Hospital. The preoperative abdominal plain CT and three-phasic contrast-enhanced CT with complete clinical files were evaluated. According to the clinical risk stratification established by the multidisciplinary diagnosis and treatment consensus for children with HB, the HB children were divided into high-risk group and non-high-risk group with 16 and 30 cases respectively. The maximum diameter of tumor, relative tumor volume index, cystic change or necrosis, bleeding, calcification, fibrous septations, tumor rupture, liver capsule retraction and subcapsular effusion were evaluated. Enhancement percentage and enhancement index on arterial, venous and delayed phases of each tumor were measured and calculated. Pearson′s χ 2 test or Fisher′s exact test were used to compare the differences in gender and lesion morphological characteristics between the high-risk group and the non-high-risk group. Two independent sample t test or Mann-Whitney U test were used to compare the differences in age, gestational age, birth weight, α-fetoprotein, platelets, maximum diameter of tumor, relative tumor volume index and CT parameters of the lesion between the two groups. Statistically significant features were included in the binary logistic regression analysis and independent predictors related to high-risk group were obtained. The ROC curve was used to determine the critical value of the high-risk group. Results:There were statistically significant differences in age, maximum diameter of tumor, relative tumor volume index and tumor rupture between the high-risk group and the non-high-risk group (all P<0.05). The logistic regression analysis showed that the maximum diameter of tumor (OR=1.906, P=0.004) and tumor rupture (OR=16.558, P=0.005) were risk factors of the high-risk group. Based on ROC curve, the optimum cut-off point of maximum diameter of tumor to predict high-risk group was 10.5 cm. Tumor rupture, maximum diameter of tumor and maximum diameter of tumor combined with tumor rupture for predicting the incidence of high-risk group resulted in the area under the curve of 0.744, 0.807 and 0.879, respectively. The sensitivity and specificity of maximum diameter of tumor combined with tumor rupture were 75.0% and 96.7%, respectively. Conclusion:The age of onset in high-risk group is relatively older. The maximum diameter of tumor greater than 10.5 cm accompanied by tumor rupture can be regarded as a high-risk sign.