Objective To explore the imaging characteristics and make the differential diagnosis of intraspinal extramedullary epidural lesions. Methods 23 cases with intraspinal extramedullary epidural lesions confirmed by puncture or surgical pathology were selected for retrospective analysis of the lesion morphology,MRI signs and the relationship between the lesion and surrounding tissues.Results Intraspinal extramedullary epidural lesions were more often located at thoracic spinal canal.The shapes of lesions were always various.The malignant tumors were irregular.It could damage the adjacent bone and grew surrounding the spinal cord.Leaping growth and multiple vertebral involvements could be seen in metastasis.The complex components of lesions were related to heterogeneous signal intensity on MRI,which could be presented with hypoGto hyperGintense on T1 WI and T2 WI.The angiolipoma showed hypoGto hyperGintense on T1 WI,and the hyperGintense signal could be suppressed with fatGsuppressed sequence.Meningioma tended to present with homogeneous signal on both T1 WI and T2 WI, with dural tail on contrast MRI.All of the lesions were moderately or significantly enhanced on contrast MRI.Conclusion Intraspinal extramedullary epidural lesions include a wide range of lesions,and the components of lesions are very complex.Among them,the distinctive MRI characteristics include the lesions containing fat and vascular components,besides malignant lesions invading adjacent tissues.Comprehensive analysis of the shape and signal of lesions,as well as the relationship between lesions,and surrounding structures is very helpful in differential diagnosis of intraspinal extramedullary epidural lesions.

Objective To assess the diagnostic value of saline infusion test ( SIT) and its optimal cutoff in the diagnosis of primary aldosteronism ( PA ), and to analyze whether the dietary salt intake affects the SIT accuracy. Methods This is a prospective study. All 236 patients with a high risk for PA underwent the screening test, SIT and the fludrocortisone suppression test (FST) in separate days. The diagnosis of PA was established according to the FST criteria. According to the 24 h urinary sodium level, the patients were divided into low salt, normal salt, and high salt groups respectively, and the effect of salt intake on SIT was analyzed. Receiver operating characteristic (ROC) analysis was performed to compare the diagnostic accuracies. Results Finally, in 236 patients with high risk for PA, 134 patients with PA and 102 patients with essential hypertension ( EH) were diagnosed. Using post-test plasma aldosterone concentration (PAC) for diagnosis, the area under the ROC curve (AUCROC) of the SIT was 0.974 (0.957, 0.991), which was significantly higher than that of the post-test plasma aldosterone to renin ratio (ARR) [0.900 ( 0. 862, 0. 938)] and that of the PAC suppression percentage [ 0. 752 ( 0. 690, 0. 813)] ( both P<0.01). Considering both sensitivity and specificity, an optimal cutoff of PAC post-SIT was set at 8 ng/dl, resulting in a sensitivity of 88. 1% and a specificity of 95. 1%. The PAC post-SIT, whether in PA or EH patients, had no statistically significant differences among low salt, normal salt, and high salt groups (P>0.05). Conclusion SIT is reliable for the diagnosis of PA. PAC post-SIT more than 8.0 ng/dl is recommended to confirm PA.

Objective To compare the imported (Diasorin,Italy) and domestic (Mindray,Shenzhen) chemiluminescent systems used in the measurement of plasma aldosterone and renin concentrations;To establish the reference interval of plasma aldosterone and renin concentrations in healthy adults.Methods With the assay instrument and its kits from Italy Diasorin as the reference system,the concentrations of plasma aldosterone and renin were measured by the two systems,in 143 healthy adults,72 patients with hypertension (16 patients with primary aldosteronism) and to establish the medical reference range (P2.5-P97.5) of them.Results The plasma aldosterone (r=0.914,P＜0.01) and renin(r=0.977,P＜0.01)concentrations detected by the two systems were positively correlated.Distribution of plasma aldosterone and renin was skewed in healthy adults.The reference interval was 30.8-344.6 pg/ml for aldosterone and 2.4-90.0 μIU/ml for renin by the imported chemiluminescent system.The reference interval was 29.4-473.3 pg/ml for aldosterone and 3.6-98.3 μIU/ml for renin by the domestic chemiluminescent detection system.Conclusion The two systems are closely correlated in measuring plasma aldosterone and renin concentrations.

Objective To observe ultrasonographic features and significance of scoring of the lung in preterm infants.Methods Totally 37 preterm infants (preterm group) and 33 term infants (term group) without cardiopulmonary disease nor hypoproteinemia were enrolled,and infants in each group were divided into＜1 week,1-4 weeks and ＞4 weeks subgroup,respectively.All the infants underwent lung ultrasonography and scoring.The ultrasonography scores were compared between preterm infants and term infants among different ages.Results The main ultrasonic manifestations of the lung in preterm infants were diffuse distribution of dense B-lines,with or without " falls sign" suggesting alveolar effusion.The ultrasonographic score of the lung in preterm infants and term infants was (15.24± 2.76) and (12.21 ±3.62),respectively (t=3.962,P＜0.001).There was no statistical difference of ultrasonographyic scores in ＜1 week subgroups between preterm infants and term infants (t =-0.669,P =0.513).There were statistical differences of ultrasonographic scores in 1-4 weeks subgroups and ＞4 weeks subgroups between preterm group and term group (both P＜0.05).In preterm group,the ultrasonographic scores demonstrated no statistical difference among 3 subgroups (F=0.960,P=0.393),whereas statistical difference was found among 3 subgroups in term group (F =4.277,P =0.023).The ultrasonographic score of preterm infants showed negative correlation with gestational age (r=-0.352,P=0.033),and the linear regressive equation was Y=33.805-0.548X.Conclusion The main ultrasonic manifestations of the lung in preterm infants were diffuse distribution of dense B-lines,some with "falls sign" suggesting alveolar effusion,which are more significant in smaller gestational age infants.