Objective:To evaluate the nutritional status of children with aplastic anemia（AA）using the children's nutritional risk index（CNRI），prognostic nutritional index（PNI），controlling nutritional status（CONUT），instant nutritional assessment（INA），and combined index（CI），in order to provide scientific evidence to support clinical diagnosis and treatment.Methods:A retrospective analysis was conducted on the clinical data of pediatric AA patients treated in the Department of Pediatrics，Ward 1，First Affiliated Hospital of Xinjiang Medical University from January 1st，2019 to April 30st，2024.Nutritional status was assessed using CNRI，PNI，CONUT，and INA，and integrated into CI.The agreement between different nutritional screening tools was evaluated using Kappa statistics. Results:A total of 68 pediatric AA patients were included，with an overall malnutrition prevalence of 44.1%.The malnutrition rates were 39.4% in the body mass index（BMI）normal group and 48.6% in the BMI abnormal group.Across disease severity groups，malnutrition was observed in 66.67% of very severe AA（VSAA）patients，54.17% of severe AA（SAA）patients，and 28.13% of non-severe AA（NSAA）patients，and the difference was statistically significant（ χ2=6.778， P=0.034）. Kappa analysis demonstrated the highest concordance between CONUT，INA，and CI，with Kappa values of 0.882（ P<0.001）. Conclusion:Pediatric AA patients have a high prevalence of malnutrition，and their nutritional status decline significantly with increasing disease severity.CONUT and INA are effective tools for assessing nutritional status in children with AA，providing reliable evidence for clinical evaluation.

Objective To investigate the best weighting of adaptive statistical iterative reconstruction (ASIR) algorithm and optimized low-dose scanning parameters in thoracic aorta CT angiography(CTA).Methods Totally 120 patients with the body mass index (BMI) of 19-24 were randomly divided into 6 groups.All patients underwent thoracic aorta CTA with a GE Discovery CT 750 HD scanner (ranging from 290-330 mm).The default parameters (100 kV,240 mAs) were applied in Group 1.Reconstructions were performed with different weightings of ASIR (10％-100％ with 10％),and the signal to noise ratio (S/N) and contrast to noise ratio (C/N) of images were calculated.The images of series were evaluated by 2 independent radiologists with 5-point-scale and lastly the best weighting were revealed.Then the mAs in Group 2-6 were defined as 210,180,150,120 and 90 with the kilovoltage 100.The CTDIvoland DLP in every scan series were recorded and the effective dose (E) was calculated.The S/N and C/N were calculated and the image quality was assessed by two radiologists.Results The best weighing of ASIR was 60％ at the 100 kV,240 mAs.Under 60％ of ASIR and 100 kV,the scores of image quality from 240 mAs to 90 mAs were(4.78 ±0.30)-(3.15 ±0.23).The CTDIvol and DLP were 12.64-4.41 mGy and 331.81-128.27 mGy,and the E was 4.98-1.92 mSv.The image qualities among Group 1-5 were nor significantly different (F =5.365,P ＞ 0.05),but the CTDIvol and DLP of Group 5 were reduced by 37.0％ and 36.9％,respectively compared with Group 1.Conclusions In thoracic aorta CT Angiography,the best weighting of ASIR is 60％,and 120 mAs is the best mAs with 100 kV in patients with BMI 19-24.