Purpose To evaluate the diagnostic accuracy of low-iodine contrast subtraction CT pulmonary angiography(CTPA)combined with iodine maps for acute pulmonary embolism(APE),with a focus on detecting subsegmental emboli.Materials and Methods A retrospective analysis included 48 patients with suspected APE who underwent both pulmonary ventilation/perfusion SPECT/CT and low-iodine subtraction CTPA within one week in Beijing Hospital from September 1,2021 to September 1,2024.Using SPECT/CT as the reference standard,the diagnostic performance of subtraction CTPA with iodine maps was assessed.A retrospective review was performed to identify potential causes of false-positive and false-negative results.Results Subtraction CTPA with iodine maps demonstrated high diagnostic accuracy at the segmental and subsegmental pulmonary artery levels,with a sensitivity of 0.917 and specificity of 0.991.At the segmental level,the detection rate was 100%,while at the subsegmental level,it was 66.7%.The method showed consistently high diagnostic performance(83.3%-100%)across different clinical risk stratifications of APE.Retrospective review identified explicable causes for 85.7%(6/7)of false-positive and 33.3%(2/6)of false-negative cases.Conclusion Low-iodine subtraction CTPA combined with iodine maps exhibits robust diagnostic efficacy for APE.Accurate recognition of characteristic perfusion defects on iodine maps may further enhance diagnostic precision.

Objective To explore the application of linaclotide combined with compound polyethylene glycol electrolyte powder(PEG)in bowel preparation for colonoscopy of patients with chronic constipation.Methods A toltal of 190 patients with chronic constipation who underwent electronic colonoscopy in Beijing NO.6 Hospital from January to October 2023 were selected as the objects.The patients were divide into linaclotide group(n=63),3L PEG group(n=64),and 4L PEG group(n=63)by random number table method.The application effects of three groups were compared.Results Boston bowel preparation scale score was higher than 3L PEG and 4L PEG groups,there were significant difference among groups(P＜0.05).The qualified rate of patients in linaclotide group was better than that of 3L PEG group and 4L PEG group,and the qualified rate of patients in 4L PEG group was better than that of 3L PEG group,there were significant difference among groups(P＜0.05).Conclusion Linaclotide combined with PEG can not only improve the intestinal cleaning quality of patients with constipation,but also do not increase the adverse reactions of patients.

Objective:To investigate the effects of low tube voltage, automatic tube current modulation technology combined with noise index(NI), and forward projected model-based iterative reconstruction solution(FIRST)on radiation dose and image quality in low iodine contrast agent CT pulmonary angiography(CTPA)among elderly patients.Methods:This retrospective study continuously collected imaging and clinical data from elderly patients suspected of having acute pulmonary embolism (APE)who underwent low-iodine contrast CTPA at the emergency department and inpatient department of Beijing Hospital from February 2022 to July 2023.A total of 80 patients were included in the study.Based on the reconstruction algorithm utilized during the CTPA examination, the patients were divided into two groups: the adaptive iterative dose reduction using three-dimensional processing(AIDR 3D)group and the FIRST group, with 40 cases in each group.We measured the average CT value and noise value of the pulmonary artery at various positions in both groups on axial images, calculated the signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR), and recorded the average tube current and effective radiation dose for both patient groups.Two observers independently performed subjective scoring on the display of the pulmonary artery in each group using a blind method.Results:There were no statistically significant differences in age, body mass index (BMI), gender, and the extent of pulmonary embolism between the AIDR 3D group and the FIRST group (all P>0.05).In comparison to the AIDR 3D group, the FIRST group exhibited a significantly lower tube current[(220.2±84.5) mA vs.(264.1±81.2) mA, t=0.463, P=0.020], resulting in an effective radiation dose reduction of 15.7%[(1.39±0.49) mSv vs.(1.65±0.41) mSv, t=0.072, P=0.043].No statistically significant differences were observed in the mean CT values, noise values, and SNR values of the main pulmonary artery, left and right pulmonary trunks, and lobar and segmental pulmonary arteries between the AIDR 3D group and the FIRST group (all P>0.05).The CNR of the AIDR 3D group was lower than that of the FIRST group in both the left and right segmental pulmonary arteries( Z=-2.473, -1.973; P=0.013, 0.049), while no significant differences were found in the other pulmonary arteries(all P>0.05).In patients with normal BMI, the FIRST group demonstrated higher CNR values in both the left and right segmental pulmonary arteries compared to the AIDR 3D group( Z=-2.008, -2.662, P=0.046, 0.007), whereas the improvement in CNR was not significant in overweight and obese patients(all P>0.05).The two radiologists provided consistent subjective evaluations in scoring(Kappa=0.744, P<0.001), and there was no statistically significant difference in subjective scores between the AIDR 3D group and the FIRST group ( χ2=0.346, P=0.770). Conclusions:The imaging technique that integrates automatic tube current modulation technology with NI, the FIRST reconstruction algorithm, and a low tube voltage of 100 kVp effectively ensures image quality by providing clear visualization of pulmonary arteries at all levels.Moreover, it reduces radiation dose during low-iodine contrast agent CTPA examinations in elderly patients with APE.

Objective:To summarize and compare the clinical characteristics of immune checkpoint inhibitor-associated pneumonia(CIP)in elderly and non-elderly lung cancer patients treated with immune checkpoint inhibitors(ICIs).Methods:We conducted a retrospective analysis of the clinical data from 61 patients who developed CIP following ICIs treatment in the Respiratory and Critical Care Medicine Department and the Oncology Department of Beijing Hospital from May 2016 to April 2024.The clinical characteristics of patients aged 65 years and older were compared with those of patients younger than 65 years.Results:A total of 61 patients were included in the study, with 26 patients in the group aged <65 years[aged 39-64(56.3±5.6)years].Within this group, the clinical grades were distributed as follows: 5 patients in grade 1(G1), 12 in grade 2(G2), 7 in grade 3(G3), and 2 in grade 4(G4).Twelve patients underwent bronchoscopy, while 17 patients received corticosteroid therapy after developing CIP.Additionally, 20 patients permanently discontinued immunotherapy due to CIP.Notably, one patient showed improvement in CIP following treatment, which allowed for the continuation of ICIs.Importantly, no patients in this group experienced mortality due to CIP.In the group aged ≥65 years[aged 65-83(71.9±4.9)years], there were 35 patients, categorized as follows: 4 in G1, 22 in G2, 5 in G3, and 4 in G4.Twenty-one patients underwent bronchoscopy, 31 received corticosteroid therapy after developing CIP, and 30 patients permanently discontinued immunotherapy due to CIP.Similarly, one patient in this group demonstrated improvement in CIP following treatment, which permitted the continuation of ICIs.Importantly, no patients in this group experienced mortality due to CIP.Compared to patients aged <65 years, those aged ≥65 years experienced a shorter median time to the occurrence of CIP, with a median of 2(1, 4)months versus 5.5(2, 8)months for the younger group( Z=-3.231, P=0.001).Furthermore, a higher proportion of patients aged ≥65 years received corticosteroid therapy after developing CIP(88.57% or 31 cases)compared to 65.38%(17 cases)in the younger group( χ2=4.704, P=0.030).There were no statistically significant differences in the occurrence of CIP symptoms or chest imaging characteristics between the two age groups(both P>0.05). Conclusions:Patients aged 65 years and older experience a shorter median time to develop CIP following the use of ICIs.However, there is no significant difference in clinical outcomes when compared to the group aged under 65 years, provided that early identification and diagnosis are achieved.

Objective:To develop a 3-year mortality risk prediction model for patients with idiopathic pulmonary fibrosis (IPF) and evaluate its performance efficiency.Methods:This retrospective study enrolled consecutive patients with idiopathic pulmonary fibrosis (IPF) at Beijing Hospital between January 2013 and December 2021. Patient was followed for ≥3 years. Cox regression analyses were used to identify risk factors of 3-year mortality and a risk prediction model for mortality risk in patients with IPF was developed and evaluated.Results:A total of 204 patients were enrolled, among whom 60 cases died and 144 cases survived during the follow-up. Patients were randomly divided into a training set ( n=142) and a validation set ( n=62) in a 7∶3 ratio. Multivariate Cox regulation analysis revealed that Charlson Comorbidity Index (CCI) score ( HR=1.589,95% CI: 1.310-1.928, P<0.001, C-index=0.716), High Resolution CT (HRCT) reticular pattern ( HR=6.901, 95% CI: 2.763-17.239, P<0.001, C-index=0.752), HRCT honeycombing sign ( HR=3.126, 95% CI: 1.871-5.223, P=0.001, C-index=0.717), and HRCT traction bronchiectasis ( HR=3.875, 95% CI:2.190-6.858, P=0.001, C-index=0.711) were risk factors for 3-year mortality. A 3-year mortality risk model for IPF patients was developed: risk score=0.654×CCI+2.174×reticular pattern (Yes=1)+2.355×honeycombing (Yes=1)+0.511×traction bronchiectasis (Yes=1). The HR of the model for training set, validation set and overall cohort were 2.718 (95% CI: 1.930-3.828, P<0.001, C-index=0.880), 2.537 (95% CI: 1.255-5.131, P=0.010, C-index=0.853) and 2.590 (95% CI: 1.910-3.512, P<0.001, C-index=0.865), respectively. The performance was evaluated by ROC curve, the areas under the curve of the model for predicting 3-year mortality were 0.903 in training set and 0.826 in validation set, respectively. Conclusion:The prediction model composing of CCI score and HRCT signs developed in this study demonstrates a good performance for 3-year mortality risk in IPF patients.

Objective:To summarize the clinical characteristics of SAPHO syndrome in elderly patients with organizing pneumonia.Methods:We reported a case of SAPHO syndrome in an elderly patient with organizing pneumonia.Relevant reports on SAPHO syndrome with organizing pneumonia at home and abroad were retrieved, and the literature was summarized an analyzed.Results:The patient was a 63-year-od female who was admitted to the hospital due to "intermittent fever and cough for more than two months". Before admission, she was previously diagnosed with pneumonia in another hospital with poor response to anti-infective treatment.Chest CT showed multiple bilateral patchy consolidations in both lungs, with migratory changes and reversed halo signs.Her medical history included bone and joint pain(e.g., sternoclavicular joints)and palmoplantar pustulosis.Lung biopsy pathology confirmed organizing pneumonia. 99mTc-MDP bone scintigraphy revealed abnormal bone salt metabolism in multiple bone and joint areas.The final diagnosis was SAPHO syndrome with organizing pneumonia.Both symptoms and imaging significantly improved after prednisone treatment.Two related cases were retrieved from the literature.One was a 57-year-old female reported in the UK, who had been diagnosed with SAPHO syndrome before and was found to have lung consolidations due to respiratory symptoms.Lung biopsy confirmed organizing pneumonia, and she improved after glucocorticoid treatment.The other was a 59-year-old Chinese female who visited hospital due to pain in the lumbosacral part and left lower limb.After being diagnosed with SAPHO syndrome, a chest CT scan was performed and lung consolidations were found.The pathology confirmed organizing pneumonia.The patient improved after treatment with Tripterygium wilfordii. Conclusion:SAPHO syndrome complicated with organizing pneumonia is rare, with diverse clinical manifestations, and responds well to glucocorticoid therapy.

Purpose To evaluate the diagnostic accuracy of low-iodine contrast subtraction CT pulmonary angiography(CTPA)combined with iodine maps for acute pulmonary embolism(APE),with a focus on detecting subsegmental emboli.Materials and Methods A retrospective analysis included 48 patients with suspected APE who underwent both pulmonary ventilation/perfusion SPECT/CT and low-iodine subtraction CTPA within one week in Beijing Hospital from September 1,2021 to September 1,2024.Using SPECT/CT as the reference standard,the diagnostic performance of subtraction CTPA with iodine maps was assessed.A retrospective review was performed to identify potential causes of false-positive and false-negative results.Results Subtraction CTPA with iodine maps demonstrated high diagnostic accuracy at the segmental and subsegmental pulmonary artery levels,with a sensitivity of 0.917 and specificity of 0.991.At the segmental level,the detection rate was 100%,while at the subsegmental level,it was 66.7%.The method showed consistently high diagnostic performance(83.3%-100%)across different clinical risk stratifications of APE.Retrospective review identified explicable causes for 85.7%(6/7)of false-positive and 33.3%(2/6)of false-negative cases.Conclusion Low-iodine subtraction CTPA combined with iodine maps exhibits robust diagnostic efficacy for APE.Accurate recognition of characteristic perfusion defects on iodine maps may further enhance diagnostic precision.

Objective To explore the application of linaclotide combined with compound polyethylene glycol electrolyte powder(PEG)in bowel preparation for colonoscopy of patients with chronic constipation.Methods A toltal of 190 patients with chronic constipation who underwent electronic colonoscopy in Beijing NO.6 Hospital from January to October 2023 were selected as the objects.The patients were divide into linaclotide group(n=63),3L PEG group(n=64),and 4L PEG group(n=63)by random number table method.The application effects of three groups were compared.Results Boston bowel preparation scale score was higher than 3L PEG and 4L PEG groups,there were significant difference among groups(P＜0.05).The qualified rate of patients in linaclotide group was better than that of 3L PEG group and 4L PEG group,and the qualified rate of patients in 4L PEG group was better than that of 3L PEG group,there were significant difference among groups(P＜0.05).Conclusion Linaclotide combined with PEG can not only improve the intestinal cleaning quality of patients with constipation,but also do not increase the adverse reactions of patients.

Objective:To investigate the effects of low tube voltage, automatic tube current modulation technology combined with noise index(NI), and forward projected model-based iterative reconstruction solution(FIRST)on radiation dose and image quality in low iodine contrast agent CT pulmonary angiography(CTPA)among elderly patients.Methods:This retrospective study continuously collected imaging and clinical data from elderly patients suspected of having acute pulmonary embolism (APE)who underwent low-iodine contrast CTPA at the emergency department and inpatient department of Beijing Hospital from February 2022 to July 2023.A total of 80 patients were included in the study.Based on the reconstruction algorithm utilized during the CTPA examination, the patients were divided into two groups: the adaptive iterative dose reduction using three-dimensional processing(AIDR 3D)group and the FIRST group, with 40 cases in each group.We measured the average CT value and noise value of the pulmonary artery at various positions in both groups on axial images, calculated the signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR), and recorded the average tube current and effective radiation dose for both patient groups.Two observers independently performed subjective scoring on the display of the pulmonary artery in each group using a blind method.Results:There were no statistically significant differences in age, body mass index (BMI), gender, and the extent of pulmonary embolism between the AIDR 3D group and the FIRST group (all P>0.05).In comparison to the AIDR 3D group, the FIRST group exhibited a significantly lower tube current[(220.2±84.5) mA vs.(264.1±81.2) mA, t=0.463, P=0.020], resulting in an effective radiation dose reduction of 15.7%[(1.39±0.49) mSv vs.(1.65±0.41) mSv, t=0.072, P=0.043].No statistically significant differences were observed in the mean CT values, noise values, and SNR values of the main pulmonary artery, left and right pulmonary trunks, and lobar and segmental pulmonary arteries between the AIDR 3D group and the FIRST group (all P>0.05).The CNR of the AIDR 3D group was lower than that of the FIRST group in both the left and right segmental pulmonary arteries( Z=-2.473, -1.973; P=0.013, 0.049), while no significant differences were found in the other pulmonary arteries(all P>0.05).In patients with normal BMI, the FIRST group demonstrated higher CNR values in both the left and right segmental pulmonary arteries compared to the AIDR 3D group( Z=-2.008, -2.662, P=0.046, 0.007), whereas the improvement in CNR was not significant in overweight and obese patients(all P>0.05).The two radiologists provided consistent subjective evaluations in scoring(Kappa=0.744, P<0.001), and there was no statistically significant difference in subjective scores between the AIDR 3D group and the FIRST group ( χ2=0.346, P=0.770). Conclusions:The imaging technique that integrates automatic tube current modulation technology with NI, the FIRST reconstruction algorithm, and a low tube voltage of 100 kVp effectively ensures image quality by providing clear visualization of pulmonary arteries at all levels.Moreover, it reduces radiation dose during low-iodine contrast agent CTPA examinations in elderly patients with APE.

Objective:To summarize and compare the clinical characteristics of immune checkpoint inhibitor-associated pneumonia(CIP)in elderly and non-elderly lung cancer patients treated with immune checkpoint inhibitors(ICIs).Methods:We conducted a retrospective analysis of the clinical data from 61 patients who developed CIP following ICIs treatment in the Respiratory and Critical Care Medicine Department and the Oncology Department of Beijing Hospital from May 2016 to April 2024.The clinical characteristics of patients aged 65 years and older were compared with those of patients younger than 65 years.Results:A total of 61 patients were included in the study, with 26 patients in the group aged <65 years[aged 39-64(56.3±5.6)years].Within this group, the clinical grades were distributed as follows: 5 patients in grade 1(G1), 12 in grade 2(G2), 7 in grade 3(G3), and 2 in grade 4(G4).Twelve patients underwent bronchoscopy, while 17 patients received corticosteroid therapy after developing CIP.Additionally, 20 patients permanently discontinued immunotherapy due to CIP.Notably, one patient showed improvement in CIP following treatment, which allowed for the continuation of ICIs.Importantly, no patients in this group experienced mortality due to CIP.In the group aged ≥65 years[aged 65-83(71.9±4.9)years], there were 35 patients, categorized as follows: 4 in G1, 22 in G2, 5 in G3, and 4 in G4.Twenty-one patients underwent bronchoscopy, 31 received corticosteroid therapy after developing CIP, and 30 patients permanently discontinued immunotherapy due to CIP.Similarly, one patient in this group demonstrated improvement in CIP following treatment, which permitted the continuation of ICIs.Importantly, no patients in this group experienced mortality due to CIP.Compared to patients aged <65 years, those aged ≥65 years experienced a shorter median time to the occurrence of CIP, with a median of 2(1, 4)months versus 5.5(2, 8)months for the younger group( Z=-3.231, P=0.001).Furthermore, a higher proportion of patients aged ≥65 years received corticosteroid therapy after developing CIP(88.57% or 31 cases)compared to 65.38%(17 cases)in the younger group( χ2=4.704, P=0.030).There were no statistically significant differences in the occurrence of CIP symptoms or chest imaging characteristics between the two age groups(both P>0.05). Conclusions:Patients aged 65 years and older experience a shorter median time to develop CIP following the use of ICIs.However, there is no significant difference in clinical outcomes when compared to the group aged under 65 years, provided that early identification and diagnosis are achieved.