Objective To determine the effects of dose reduction on multi-slice spiral CT(MSCT) of neonatal head and assess the lowest possible radiation for acceptable clinical images.Methods Fifty-seven newborns suspected intracranial hemorrhage were entered into the study and underwent MSCT scans.Original images at three anatomic levels (posterior fossa, basal ganglia, centrum semiovale) were collected and synthetic noise was added so as to simulate dose reductions of 25%, 40%, 50% and 70%, respectively by using the noise addition tool.A total of 855 image data sets were obtained for the 57 patients.Original and simulated dose-reduction scan images were analyzed.Image noise and image quality were assessed by two independent experienced pediatric radiologists using diagnostic acceptability score, subjective image noise score on a 5-peint scale and objective noise index.Image noise was measured by respectively placing region of interest (ROI) at cerebellum, thalamus and corona radiata of 3 different slices.And the noise index and mean value was calculated.The degree of inter-observer concordance was determined by Kappa statistical analysis.The Spearman statistical correlations between the noise index and diagnostic acceptability score were performed.Results On the images of original dose and simulated dose reductions of 25%, 40%, 50% and 70%, the diagnostic acceptability was 4.47±0.51, 3.96±0.33, 3.21±0.45, 2.92±0.32, and 1.85±0.57, respectively,the subjective image scores were 1.62±0.48, 1.99±0.48, 2.76±0.81, 3.19±0.67, and 4.27±0.54, respectively, the noise index were 1.90±0.19, 2.17±0.20.2.44± 0.25, 2.68±0.28, and 3.37±0.39, respectively.The two radiologists had good intembserver agreement for diagnostic acceptability (K=0.860, P=0.017) and for image noise scoff ng (K=0.630, P=0.022).There was significant statistical correlation between image noise index and diagnostic acceptability (r= 0.826,P=0.001).At 40% dose reduction to the standard protocol, the noise index was 2.44 and the image quality score was 3.21 which were considered clinically acceptable.Conclusion The study revealed that acceptable imagos could be obtained with mean noise index of 2.44 and 40% dose reduction.

Objective To evaluate the role of multi-slice computed tomography (MSCT) in the diagnosis of pulmonary sequestration.Methods MSCT scans of 18 cases of pulmonary sequestration proved by surgery and pathology were reviewed.All cases underwent plain and contrast enhanced CT scanning,and retrospective reconstruction was made.Various reconstruction techniques in displaying the pulmonary sequestration and associated malformation were evaluated.Results Anomalous systemic arterial supply was discovered by transverse CT images in 12 cases.The reconstructed images using multiple methods showed the aberrant artery more clearly in all cases,including 6 cases in which the abnormalities were not confirmed by transverse CT.Drainage vein was revealed in 13 cases and lung heteroplasia with other malformation was demonstrated in 14 cases.Volume rendering (VR) reconstruction is the optimal choice for displaying the abnormal vessels and airway.Conclusion Enhanced MSCT with image post-processing can show the abnormal artery and vein of the pulmonary sequestration and the associated malformation,so it is the first choice in diagnosing pulmonary sequestration in pediatric population.

Objective To study the application CT scans in Nuss procedure for pectus excavatum. Metlhods 648 children with pectus excavatum underwent Nuss procedure from July 2002 to September 2008 The preoperative CT scan was carried out for evaluation of the deformity degree and morphology classification of chest wall malformation, the deformity in relation with adjacent tissue and associated different disorder. Results Nuss procedure was successfully performed in all 648 patients. The preoperative CT scan showed medium deformity of the pectus excavatum in 73 cases ( 11.27% ) and severe deformity in 575 cases (88.73%). Morphologic classification of the pectus excavatum were symmetric type in 407cases (62.81% ) , eccentric type in 83( 12.81% ) ,and unbalanced type in 158( 24.38% ). 116 cases with pectus excavatum were associated with other different disorders, among them 55 cases ( 17.9% )were diagnosed by CT scan. 28 cases received stimultanously operation for their abnormalities. Conclusion CT scan is a useful tool for evaluation the deformity degree and morphology classification, direct the operation, reduce the complications and find other different disorders. It should be a routine examination before Nuss procedure.

Objective To explore the imaging features on chest radiograph and CT in children with Influenza A H1N1 pneumonia. Methods The imaging data of chest radiograph and CT in six children with Influenza A H1N1 pneumonia confirmed by real-time RT-PCR assay was retrospectively analysis. All patients had chest radiograph at first examination and 4 of them re-examed. One children took CT. Results All cases showed thick lung markings with varied degrees of pulmonary infiltration and interstitial changes on chest radiograph. Among them, 3 cases showed bilateral pulmonary infiltration and 3 cases showed infiltration in left lung; enlarged hilar was observed in 3 cases. The imaging findings of the pneumonia changed quickly during the follow-up accompanied with the improvement of clinical symptoms. The only one chest CT examination showed bilateral infiltration, multiple ground-glass opacities,small subpleural nodulars, right pleural effusion and lymphadenopathy of lung hila and mediastinum. Conclusions Chest radiograph and CT revealed certain typical imaging features in the children with influenza A H1N1 pneumonia. However, the final diagnosis of influenza A H1N1 pneumonia still should be made based on epidemiology and laboratory examination.

Astragalus Plant ; chemistry ; Drugs, Chinese Herbal ; pharmacology ; Genes, MHC Class I ; genetics ; HL-60 Cells ; Humans ; K562 Cells ; Killer Cells, Natural ; drug effects ; Leukemia ; genetics ; metabolism ; Polysaccharides ; pharmacology

Objective Base on the local pathology, the early diagnosis and a reasonable treatment for congenital esophageal stenosis (CES) were discussed. Methods Forty two cases of congenital esophageal stenosis during 1980～2000 were reviewed retrospectively, including age, vomitus and frequency, nutrition and development, diagnostic method used and operative pathological findings, time of normal feeding and time of nutritional restoration. Results According to local pathology, there were 26 cases of tracheobronchial remnant, 11 fibromuscular stenosis, 3 membranous diaphragm, and 2 ectopic gastric mucosa. Membranous diaphragm excision gave the best result without postoperative dilatation. The patients were followed up for 4～10 years, Normal feeding was restored in 1 month in 78 6%, 9 5% in 6 months, and 11 9% in 1 year. Conclusion Persistent vomiting of undigested food and failure in gaining weight are the chief complaints of congenital esophageal stenosis. The confirmatory diagnosis depends on barium swallowing and esophagoscopy. A good result can be achieved by follows local resection and necessary postoperative dilatation.

Objective To study the value of chest radiograph and thin-section computed tomography (CT) in diagnosis bronchiolitis obliterans in children, and to determine clinical view of obliterative bronchilitis in children. Methods We identified 12 infants, 10 boys, and 2 girls (age range, 5 month to 11 years) with clinical confirmation of bronchiolitis obliterans. Three cases were after Steven-Johnson syndrome, 8 were post-infection(2 adenovirus, 2 measles and 1 Pseudomonas aeruginosa infection, 3 cases were unknown etiology infection) ; The symptoms lasted for at least 6 weeks. One case had lung ventilation nuclear scan. We evaluated individual bronchscopy, pulmonary function test, chest radiograph and thin-section CT features and their characteristic appearance. Results All cases had typical clinical characteristics and pulmonary function testing results that were consistent with nonreversible small airways obstruction. One case had lung ventilation nuclear scan illustrated absent and reduced ventilation of the right lower lobe. Nine cases who underwent bronchoscopy were chronic endobronchial inflammation. Three children had transbronchial biopsy and 1 patient who underwent open pulmonary biopsies were uncertain of histological diagnosis. Chest radiography showed hyperinflation in 8 cases; peribronchial thickening in 6 cases; consolidation/atelectasia in 6 cases; unilateral hyperlucency of a small/normal-sized lung in 4 cases. Thin-section CT/HRCT features included: mosaic perfusion pattern, decreased lung attenuation in 11 cases, pulmonary vascular attenuation in 10 cases; bronchial dilatation in 7 cases; bronchial wall thickening in 9 cases; unilateral hyperlucency of a small/normal-sized lung in 5 cases; consolidation in 6 cases; nodular in 3 cases; mucoid impaction in 5 cases. Conclusions In our study, correct diagnoses of bronchiolitis obliterans in children were made more special with thin-section CT than with chest radiographs. The diagnosis of BO in children can be based on the characteristic clinical situation, pulmonary function, indicating minimally reversible airways obstruction and characteristic thin-section CT findings.

BACKGROUND:Alendronate is a new generation of diphosphate,which is the second generation of osteoporosis drugs.It is widely used to treat diseases related to increase of bone absorption in clinic.OBJECTIVE:To observe the effect of alendronate on the proliferation and the mRNA expression of osteoprotegerin(OPG) and receptor activator of nuclear factor kappa B ligand(RANKL) of human osteoblasts.DESIGN,TIME AND SETTING:A single sample observational experiment was performed at the Basic Research Institute of Chongqing Medical University from November 2007 to March 2008.MATERIALS:Osteoblasts were isolated from cancellous bone in a surgical operation.Alendronate was the product of Merck Sharp & Dohme S.p.A.METHODS:Osteoblasts were cultured with various concentrations of alendronate(1?10-9,1?10-8,1?10-7,1?10-6,1?10-5,1?10-4 mol/L).Osteoblasts cultured without alendronate were assigned as controls.MAIN OUTC0ME MEASURES:①The morphology and growth of osteoblasts were observed.②Effect of alendronate on the proliferation of osteoblasts were detected by MMT method.③The effect of various concentrations of alendronate on the mRNA expression of OPG and RANKL were detected by using RT-PCR.RESULTS:1?10-5 and 1?10-4 mol/L alendronate inhibited the proliferation of osteoblasts.1?10-9-1?10-6 mol/L alendronate promoted the proliferation of osteoblasts,and the 1?10-8 mol/L alendronate had the strongest effect.Alendronate inhibited RANKL mRNA expression in a concentration-dependent manner,1?10-5 mol/L alendronate had a strongest effect at 72 hours after culture(P

Objective To investigate the characteristics of spinal MR images in acute flaccid paralysis(AFP) associated with enterevirus 71 infected hand-foot-mouth disease.Methods The spinal MR images of eight infants with AFP and positive EV71 cultures were analyzed during an outbreak of hand-foot-mouth disease in China in 2008.Results Acute paralysis was observed in one lower limb in 4 of the 8 patients,in four limbs in 2 patients,in one upper limb and both lower limbs in 1 patient,2 of the 8 patients also had brain stem encephalitis.Lesions were identified in anterior horn regions of spinal cord with hyperintensity on T2-weighted images and hypointensity on T1-weighted images.Location of the lesions included C3 to C7(1 case),T10 extending to conus medullaris(5 cases)and a combination of the above (2 cases).Five of the 8 patients presented with unilateral paralysis.Two of the 5 cases showed unilateral hyperintense lesions in anterior horn regions and the remaining 3 cases showed bilateral hyperintense lesions in anterior horn regions with a unilateral predominance.One of the 3 patients with bilateral lesions showed slight enhancement of anterior horn with prominent enhancement of ventral roots after intravenous injections of contrast medium.Three of the 8 patients with bilateral paralysis showed bilateral hyperintensity in both anterior horn regions.Conclusion MR is the imaging medality of choice for the detection of radiculomyelitis of AFP associated with EV71 infection.

Objective To assess the clinical value of MSCT in congenital esophageal atresia (EA) and tracheoesophageal fistula (TEF) of newborns. Methods Twenty neonates (17 boys and 3 girls) with a mean age of 4.6 days (1 day to 16 days) diagnosed EA and distal TEF underwent MSCT, and multiple planar volume reconstruction (MPVR) and three-dimensional transparency lung volume rendering (TL-VR) imaging were used. The initial diagnosis was made on esophagram by showing the catheter into a blind-ended esophageal pouch. The MSCT manifestations were compared with the surgical findings. Statistical analysis was performed by using SPSS 10.0. Paired-Samples t test and Pearson correlation analysis were used. Results MSCT clearly showed the distal esophageal pouches in all EA patients. The distance between the proximal and distal esophageal pouches determined by MPVR (0.15--3.10 cm, median 0.70 cm) and TL-VR (0.10--3.10 cm, median 0.82 cm) had no remarkable differences and correlated well with the surgical findings (r=0.87, P<0.01). MPVR revealed the orifice of the fistula in 13 TEF cases, while TL-VR only in 4. Conclusion MSCT is an useful and noninvasive imaging method for demonstrating congenital EA and distal TEF, and is highly valuable for surgical planning.