Objective:To investigate the feasibility of the combination of free breathing with the high-threshold, short-delay technique in reducing radiation dose and the volumes of iodinated contrast agent in coronary computed tomography angiography (CCTA) for obese patients.Methods:The data of 73 obese patients with weights > 85 kg and body mass indices (BMIs) > 30 kg/m 2 who received CCTA in the Radiology Department of the Peking University Third Hospital from February 2023 to May 2024 were prospectively collected. These patients were divided into a control group (31 patients) and an experimental group (42 patients). Data were collected from the control group and experimental groups under breath-holding and free-breathing conditions, respectively. The bolus tracking thresholds, delay times, and ICA injection durations were set at 100 HU, 7 s, and 12 s for the control group and at 250 HU, 2 s, and 8 s for the experimental group, respectively. Other scanning and reconstruction parameters of both groups were consistent. The CT values and their standard deviations ( SD) of both groups were assessed and compared, with the CT values involving the lumens of the aorta (AO) root, left anterior descending (LAD), left circumflex artery (LCX), and right coronary artery (RCA). The signal-to-noise ratios (SNR) and contrast-to-noise ratio (CNR) were also calculated. The subjective assessment of image quality was performed for the 18 coronary artery segments using a 4-point scale. The effective radiation doses ( E) and the volumes of iodinated contrast agent of both groups were recorded and compared. The statistical differences in the aforementioned parameters between the groups were tested and analyzed using the analysis of variance (ANOVA), the Mann-Whitney U test, or the χ 2 test. With the results of the ICA as the gold standard, the diagnostic performance of the combination of free-breathing with the high-threshold, short-delay technique in CCTA for obese patients was assessed. Results:There was no statistically significant difference ( P > 0.05) in coronary artery images between both groups, specifically regarding the CT, SNR, and CNR values of the lumens of the AO roots, LAD, LCX, and RCA, as well as the SD values of the AO roots. Both groups received subjective scores of ≥ 3 for coronary artery images, meeting the diagnostic criteria, with no statistically significant differences ( P > 0.05). Compared with the results of the ICA, the analyses of the coronary artery segments of 23 patients from the experimental group, revealed that the accuracy, sensitivity, and specificity of CCTA in the diagnosis of > 50% stenosis were 89%, 86%, and 97%, respectively. Compared to that (45 ml) of the control group, the volume (30 ml) of iodinated contrast agent of the experimental group decreased by 33.3%, with no statistically significant difference in the effective radiation dose ( E) between both groups ( P > 0.05). Conclusions:The combination of free breathing with the high-threshold, short-delay technique can further reduce the volume of the ICA for obese patients while maintaining high CCTA image quality and diagnostic performance.

Objective:To investigate the feasibility of the combination of free breathing with the high-threshold, short-delay technique in reducing radiation dose and the volumes of iodinated contrast agent in coronary computed tomography angiography (CCTA) for obese patients.Methods:The data of 73 obese patients with weights > 85 kg and body mass indices (BMIs) > 30 kg/m 2 who received CCTA in the Radiology Department of the Peking University Third Hospital from February 2023 to May 2024 were prospectively collected. These patients were divided into a control group (31 patients) and an experimental group (42 patients). Data were collected from the control group and experimental groups under breath-holding and free-breathing conditions, respectively. The bolus tracking thresholds, delay times, and ICA injection durations were set at 100 HU, 7 s, and 12 s for the control group and at 250 HU, 2 s, and 8 s for the experimental group, respectively. Other scanning and reconstruction parameters of both groups were consistent. The CT values and their standard deviations ( SD) of both groups were assessed and compared, with the CT values involving the lumens of the aorta (AO) root, left anterior descending (LAD), left circumflex artery (LCX), and right coronary artery (RCA). The signal-to-noise ratios (SNR) and contrast-to-noise ratio (CNR) were also calculated. The subjective assessment of image quality was performed for the 18 coronary artery segments using a 4-point scale. The effective radiation doses ( E) and the volumes of iodinated contrast agent of both groups were recorded and compared. The statistical differences in the aforementioned parameters between the groups were tested and analyzed using the analysis of variance (ANOVA), the Mann-Whitney U test, or the χ 2 test. With the results of the ICA as the gold standard, the diagnostic performance of the combination of free-breathing with the high-threshold, short-delay technique in CCTA for obese patients was assessed. Results:There was no statistically significant difference ( P > 0.05) in coronary artery images between both groups, specifically regarding the CT, SNR, and CNR values of the lumens of the AO roots, LAD, LCX, and RCA, as well as the SD values of the AO roots. Both groups received subjective scores of ≥ 3 for coronary artery images, meeting the diagnostic criteria, with no statistically significant differences ( P > 0.05). Compared with the results of the ICA, the analyses of the coronary artery segments of 23 patients from the experimental group, revealed that the accuracy, sensitivity, and specificity of CCTA in the diagnosis of > 50% stenosis were 89%, 86%, and 97%, respectively. Compared to that (45 ml) of the control group, the volume (30 ml) of iodinated contrast agent of the experimental group decreased by 33.3%, with no statistically significant difference in the effective radiation dose ( E) between both groups ( P > 0.05). Conclusions:The combination of free breathing with the high-threshold, short-delay technique can further reduce the volume of the ICA for obese patients while maintaining high CCTA image quality and diagnostic performance.

Objective To investigate the expression of PIK3CA,phosphorylated protein kinase B(p-AKT)and phosphatase and tensin homologue deleted on chromosome 10(PTEN)in sinonasal squamous cell carcinoma(SNSCC).Methods The expressions of PIK3CA and PTEN in head and neck squamous cell carci-noma(HNSCC)were analyzed through the data set of HNSCC in the cancer genome map of UCSC Xena data-base.The immunohistochemical SP method was used to measure the expression of PIK3CA,p-AKT and PTEN in 43 cases of SNSCC tissues,20 cases of normal inferior concha tissues.The relationship between the expressions of PIK3CA,p-AKT and PTEN protein with the clinicopathological features and prognosis of the patients with SNSCC was analyzed.Results The results of bioinformatic analysis showed that PIK3CA mR-NA expression in HNSCC tissues was higher than that in paracancerous tissues(P＜0.01),while the PTEN mRNA expression was lower than that in paracancerous tissues(P＜0.05).The immunohistochemical detec-tion results showed that the positive expressions rates of PIK3CA and p-AKT proteins in normal nasal mucosa tissues were significantly lower than those in SNSCC tissues,while the positive expression rate of PTEN pro-tein in SNSCC tissues was significantly higher than that in normal inferior nasal concha mucosa tissues,and the differences were statistically significant(P＜0.01).The expressions of PIK3CA and p-AKT protein were related to the clinical stage,differentiation degree and primary site(P＜0.05),but were not related to age,gender,smoking and drinking(P＞0.05);the PTEN protein expression was not related with the clinical stage,differentiation degree,primary site,age,smoking and drinking(P＞0.05).The Spearman analysis showed that the expression of PIK3CA in SNSCC tissues was positively correlated with p-AKT protein ex-pression(r=0.664,P＜0.01),and PIK3CA was negatively correlated with PTEN protein(r=-0.414,P＜0.01).The expression of p-AKT was negatively correlated with PTEN protein(r=-0.453,P＜0.01).The Kaplan-Meier analysis showed that the median survival time of the patients with PIK3CA and p-AKT protein positive expression was shorter than that of the patients with negative expression(P＜0.01).There was no statistically significant difference in median survival between the patients with PTEN protein positive expres-sion and those with negative expression.Conclusion The overexpressions of PIK3CA and p-AKT accompa-nied by the loss of PTEN expression participate in the development and progression of SNSCC,moreover the PIK3CA and p-AKT expressions are related to the poor prognosis of the patients.

Objective:To evaluate the feasibility of low radiation dose and low contrast dosage in coronary CT angiography (CCTA) of class I obese patients.Methods:This prospective study enrolled 57 patients (male/female, 50/7, age, 25-77 years) with body mass index (BMI) of 30-38 kg/m 2 and body weight of 85-119 kg scheduled for CCTA from August 2022 to March 2023 in our hospital. The patients were divided into two groups: control group (group A, n = 20) and low-dose group (group B, n = 37). Group A employed a standard-dose protocol: tube voltage 120 kVp and IDR 2.2 g I/s, while group B were scanned using the low-dose protocol: tube voltage 100 kVp and IDR 1.5 g I/s. Images in Group A and Group B were reconstructed with hybrid iterative reconstruction (HIR) at strength 4 and 8, respectively. Other scanning and reconstruction parameters were the same in two groups. Methods:The image quality was assessed by measuring the CT values and noise in the aortic root, left anterior descending artery and right coronary artery, and the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Subjective image quality was evaluated for vessels according to the 18-segment classification system using a 4-point scale (1. poor, 4. excellent). The effective dose E and contrast dosage were compared. Statistical analysis was performed using independent samples t-test, Mann-Whitney U test or χ 2 test. Results:The BMI of groups A and B were 31.89 (30.77, 33.81) and 31.22 (30.46, 32.83) kg/m 2, respectively ( P>0.05). No statistically significant differences in CT values, noise, SNR, CNR were noticed between the two groups (all P>0.05). The mean subjective score of all coronary artery segments in the two groups were not less than 3, meeting the requirement of clinical diagnosis. There was no statistically significant difference in the overall subjective image quality between the two groups ( P>0.05). The radiation dose E in groups A and B were 7.58 and 4.49 mSv, respectively ( Z=-5.46, P<0.05). The contrast dosage in groups A and B were 66 and 45 ml, respectively. The radiation dose E and contrast dosage in group B were 41% and 32% lower than that in group A, respectively. Conclusions:For class I obese patients, it was feasible to use a low tube voltage (100 kVp) and low IDR (1.5 gI/s) protocol in CCTA. Radiation dose and contrast dosage can be reduced reasonably without compromising the CCTA image quality.

Objective To analyze the clinical characteristics and prognostic factors of deep cervical abscesses.Methods The medical records of 166 patients with deep cervical abscesses who underwent emergency surgical treatment in the Department of Otolaryngology of our hospital between October 2014 and August 2023 were retrospectively analyzed.The age-adjusted Charlson comorbidity index(aCCI)was calculated based on the data obtained.The patients were divided into good and poor prognosis groups,and multivariate logistic regres-sion was used to analyze the impact of various indicators on the prognosis of the two groups of patients.Results Statistically significant differences in sex,age,mediastinal infection,sepsis,diabetes,hypertension,C-reactive protein(CRP)and procalcitonin(PCT)levels,and the aCCI scores were observed between the two groups(P<0.05).Thus,these factors have a significant impact on the prognosis of patients with deep cervical abscesses.Multivariate regression analysis showed that mediastinal infection,hypertension,and the aCCI score were independent predictors of poor prognosis in patients with deep cervical abscesses(P<0.05).Conclusion Mediastinal infection,hypertension,and the aCCI score are independent risk factors for poor prognosis in patients with deep neck abscesses and can be used to preliminarily evaluate the prognosis of patients with deep cervical abscesses.

BACKGROUND: Few studies have explored the modifications by family stress and male gender in the relationship between early exposure to traffic-related air pollution (TRAP) and allergic rhinitis (AR) risk in preschool children. METHODS: We conducted a case-control study of 388 children aged 2-4 years in Shenyang, China. These children AR were diagnosed by clinicians. By using measured concentrations from monitoring stations, we estimated the exposures of particulate matter less than 10 μm in diameter (PM RESULTS: The prevalence of AR in children aged 2-4 years (6.4%) was related to early TRAP exposure. With an IQR (20 μg/m CONCLUSIONS Family stress and male gender may increase the risk of AR in preschool children with early exposure to PM
Air Pollution/adverse effects* ; Case-Control Studies ; Child, Preschool ; China/epidemiology* ; Cities ; Family/psychology* ; Female ; Humans ; Male ; Prevalence ; Rhinitis, Allergic/epidemiology* ; Risk Factors ; Stress, Psychological/complications* ; Traffic-Related Pollution/adverse effects*

ViewRay magnetic resonance (MR) guided radiotherapy system not only solves the problem of imaging dose,but also can set up accurately,online adaptive radiotherapy and gated irradiation according to magnetic resonance imaging (MRI).The development of this system provides a new technical means of accurate radiotherapy.This review describes the main structure of the ViewRay system,and summarizes quality assurance (QA),dosimetric comparison,respiratory motion management,online adaptive radiotherapy,and preliminary treatment effect.

Objective To discuss the clinical value of image navigation technique in nasal endoscopic repair of cerebrospinal fluid rhinorrhea. Methods Retrospectively analyse the clinical data of 10 cases with cerebrospinal fluid rhinorrhea who underwent nasal endoscopic repair who were admitted to hospital from March 2014 to June 2017 and discussing the diagnosis of cerebrospinal fluid rhinorrhea, preoperative and intraoperative leakage location,repair effect,complications and other indicators. Results All cases were cured by one treatment under imaging-guided transnasal endoscopic repair without any complication and recurrence during the 0. 5 to 40 months of follow-up visits. Conclusion Image-guided system application is essential in the endoscopic repairment of cerebrospinal fluid rhinorrhea by exactly locating the rhinorrhea.

Objective To investigate the expression of minichromosome maintenance protein 7 (MCM7) in sinonasal squamous cell carcinoma (SNSCC),and evaluate its relationship with tumor differentiation and prognosis of patients.Methods Using immunohistochemistry,MCM7 expression in SNSCC and nasal polyps with chronic sinusitis (NPCRS) were studied,and relationships between markers and clinicapathological features were analyzed.Results In NPCRS,MCM7 positive cells were mainly distributed in the epithelial basal layer and the expression rate was low,whereas in SNSCC,MCM7 positive cells were diffuse and the expression rate was high.MCM7 expression was significantly higher in SNSCC than in NPCRS (P ＜ 0.001) and related to tumor differentiation (P =0.001),increasing gradually with decreasing degree of differentiation.The overall 3-and 5-year survival rates of patients with SNSCC were 61.3％ and 46％,respectively.The 3-year survival rates for patients with stage Ⅰ and Ⅳ were 90％ and 25.6％,respectively,and the 5-year survival rates were 70％ and 17.1％,respectively;the difference was statistically significant (P ＜ 0.001).The 3-and 5-year survival rates of MCM7-negative patients were 36.0％ and 18.0％,respectively,and those of MCM7-positive patients were 59.9％ and 34.2％,respectively;the difference was not statistically significant (P =0.297).Conclusion In SNSCC,MCM7 expression is significantly increased,inversely associated with the degree of tumor differeutiation,and unrelated to the survival rates of patients.