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Objective To evaluate the imaging characteristics of atypical teratoid/rhab doid tumor (AT/RT) of central nervous system(CNS), and to improve the diagnostic ability of the disease. Methods The clinical and imaging findings of 9 patients were retrospectively analyzed. There were 5 male and 4 female, ages 7 months to 5 years,median age was 1.4 years. MR enhancement studies were obtained in all the cases. One case had CT enhancement examination. Results The lesions were seen in brain in 8 cases and in lumbosacral spinal cord in one case. The tumors size varied from 4.8—7.8 cm, Necrosis was seen in nine cases, cystic change in eight cases and hemorrhage in five cases. The tumors had high signal on DWI, and low signal on ADC map. Dura matter invasion(2 cases), cerebrospinal fluid spread(2 cases)and intracerebral metastasis were seen. Conclusion There are some relatively specific imaging findings of primary CNS AT/RT that could assist their diagnosis.
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Objective To investigate the value of routine MRI in determining placental grading and the relationship between placental apparent diffusion coefficient(ADC)value and the gestational age(GA)in the second and third trimesters of pregnancy. Methods 52 women with singleton pregnancies were referred for MRI examination for underlying maternal or fetal lesions or malformations identified by ultrasound(US).Subjects were divided into three groups according to the GA:group Ⅰ at 18 -26 weeks(n=29);groupⅡat 27-33 weeks(n=14);group Ⅲ at 34-40 weeks(n=9).DWI protocol included 2 sets of b-values:0 s/mm2,200 s/mm2,800 s/mm2 and 50 s/mm2,200 s/mm2,800 s/mm2,and ADC values of the two groups were calculated and correlated with GA by simple linear regression.Results Half-fourier acquisition single-shot turbo spin-echo(HASTE)sequence could clearly define the 3 layers of placenta and determine the grading of placental aging.ADC values with b values of 0 s/mm2,200 s/mm2and 800 s/mm2were correlated negatively with GA (r= -0.900,P<0.001).However,ADC values with b values of 50 s/mm2,200 s/mm2and 800 s/mm2did not show any statistical correlation with GA(r= -0.037,P=0.795).Conclusion MRI can visualize the morphological changes of the placenta during the pregnancy.With a set of b-values at 0 s/mm2,200 s/mm2and 800 s/mm2,placental ADC values are found to have decreasing tendency as the pregnancies progress in the second and third trimesters.
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Objective To investigate the value of four-dimensional color Doppler in diagnosis of fetal cleft lip and cleft palate.Methods The four-dimensional color Doppler for 24-28weeks of pregnancy in 13 548 pregnant women by prenatal ultrasound.Results Found 21 cases of fetal cleft lip and cleft palate,2 cases were missed,were confirmed.Conclusion Four dimensional color Doppler dynamic continuous observation of the fetal activity,plays an important role in diagnosis of fetal cleft lip and cleft palate and typing,which can increase the detection rate of fetal cleft lip and palate.
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Objective To investigate the diagnostic value of prenatal ultrasonography and magnatic resonance imaging in the fetal intracranial hemorrhage. Methods The 20 antenatal diagnosed ICH cases was collected from 31 200 prenatal diagnosis units in Guangzhou Women and Children′s Medical Center from July 2012 to June 2014. Maternal characteristics, ultrasound, and magnetic resonance imaging findings, clinical course, and postnatal outcome were reviewed. Results Twenty consecutive cases of fetal ICH were evaluated. All cases were diagnosed at mid or third trimester. Transabdominal ultrasound showed 9 cases of hyper echoic lesions in the lateral ventricle, 2 cases of hypoechonic lesions, 2 cases of irregular mixed echo in the parenchyma, 1 case of hyperechoic cerebellar hemisphere with infarction, and 1 case of abnormal choroid plexus. Seventeen cases were associated with ventriculomegaly, brain compression or brain midline displacement. MRI showed the nodular, patchy or linear low signal on T2WI and high signal on T1WI. Some cases were combined with cortex lesions or abnormal parenchyma. ICH was complicated with other structural abnormalities:1 case of cleft palate, 2 cases of spinal deformity and 3 cases of other cerebral cortical malformations. Prenatal diagnosis results were:2 cases diagnosed as positive cytomegalovirus infection and no chromosome abnormalities found in all cases. The follow up results were:1 case was lost, 16 cases were terminated after prenatal diagnosis. Among the 3 survival cases, 1 case has the neurological complication and the other two were normal till now. Conclusions Fetal intracranial hemorrhage has some image features on ultrasound and magnetic resonance. Ultrasound showed hyper echoic lesions with ventriculomegaly. MRI showed the nodular, patchy or linear low signal on T2WI and high signal on T1WI. MRI may contribute to the accuracy of diagnosis, particularly in bleeding site. The regular ultrasonic monitoring is helpful to improve the detection rate.
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<p><b>OBJECTIVE</b>To assess the value of voiding urosonography (VUS) with SonoVue in evaluation of vesicoureteral reflux.</p><p><b>METHODS</b>Thirty-six pediatric patients (72 pyeloureter units [PUUs]) suspected of vesicoureteral reflux underwent both VUS and fluoroscopic voiding cystourethrography (VCUG). The sensitivity of VUS and VCUG and their consistency in detecting vesicoureteral reflux as well as in grading vesicoureteral reflux were compared.</p><p><b>RESULTS</b>Vesicoureteral reflux was detected in 26 of the 72 PUUs (36.1%) by VUS while in 21 PUUs (29.2%) by VCUG (P=0.347). The two modalities yielded the same results for 65 PUUs (κ=0.843), showing a very good consistency between them. VUS also detected post-urethral valve in 2 patients via transperineal scans.</p><p><b>CONCLUSION</b>VUS with Sonovue has at least comparable, if not better, sensitivity in detecting vesicoureteral reflux with VCUG, and therefore should serve as the primary screening and follow-up modality for vesicoureteral reflux. In addition, transperineal VUS can be helpful in evaluation of post-urethral lesions.</p>