1.Analysis of the trend of radiological diagnostic examination frequency and the related influencing factors
Yongxian ZHANG ; Yantao NIU ; Tianliang KANG ; Yunfu LIU ; Liping XU ; Lin XU ; Senlin GUO ; Dandan LIU ; Binbin YU ; Junfang XIAN
Chinese Journal of Radiological Medicine and Protection 2024;44(1):29-35
Objective:To investigate the trend of radiological diagnostic examination frequency and the related influencing factors in a general hospital in recent four years.Methods:The hospital information system and the radiology information system were used to collect the information on the numbers of the outpatients, the emergency patients, and the inpatients and the radiology examination information from 2019 to 2022. The examination frequency and proportion of various imaging equipment were counted by using the perspective table of data, and the examination items and the proportion of the radiological diagnostic examinations were calculated. The positive rates of the radiological examinations were measured from 2019 to 2022. The gender and age distribution of the patients were analyzed. Spearman correlation analysis was used to analyze the relationships between the numbers of the patients undergoing radiological examinations and the numbers of the outpatients, emergency patients and the inpatients.Results:The annual frequency of radiological diagnostic examinations from 2019 to 2022 were 307 306, 245 418, 317 250 and 325 625, respectively, with a total of 1 195 599. Among them, the proportions of CT, X-rays, bedside X-rays, bone density, gastrointestinal imaging and mammography were 59.74%, 38.04%, 1.39%, 0.42%, 0.21% and 0.19%, respectively. In each year, the proportion of CT in all radiological diagnostic examinations was 49.58%, 63.40%, 60.40% and 65.20%, respectively. The frequency of emergency CT and emergency chest CT was correlated with the number of emergency patients( r =0.63, 0.61, P<0.05), and the frequency of non-emergency CT was correlated with the number of outpatients and inpatients ( r =0.61, 0.66, P<0.05). The positive rates of the CT examinations were higher than 80% except the lowest of 79.95% in 2021. Conclusions:Radiological examinations especially CT examinations have increased significantly, and played an important role in the diagnosis of diseases. However, attention should be paid to the Justification of the CT examinations. Timely statistical analysis of radiological examination information can provide data supports and references for scientific management of radiological examinations.
2.Spatial radiomics model for identifying supratentorial pilocytic astrocytoma and ganglioglioma based on MRI
Tianliang ZHAN ; Jianrui LI ; Qiang XU ; Zhizheng ZHUO ; Junjie LI ; Haohui CHEN ; Ya'ou LIU ; Zhiqiang ZHANG
Chinese Journal of Radiology 2024;58(12):1381-1387
Objective:To construct a spatial radiomics model based on the spatial distribution characteristics of supratentorial pilocytic astrocytoma (PA) and ganglioglioma (GG) and to evaluate its differential diagnosis efficiency.Methods:The study was a cross-sectional study. A retrospective collection of 244 patients with episodic PA and GG who attended Beijing Tiantan Hospital of Capital Medical University (Center 1) from June 2016 to June 2022 and 116 patients with episodic PA and GG who attended General Hospital of Eastern Theater Command (Center 2) from March 2019 to October 2022 was performed. The patients in Center 1 were divided into a training set (171 patients) and a validation set (73 patients) in a 7∶3 ratio according to the random number table method, and the patients in Center 2 as a whole were regarded as test sets. All patients underwent MRI. Segmentation of tumor based on enhanced T 1WI and T 2WI images, alignment to standard space to generate a statistical parametric mapping of tumor locations and intergroup comparison was conducted. The Johns Hopkins University template was used to extract 189 tumor location features to construct a spatial model of tumor location; PyRadiomic 3.0.1 software was used to extract tumor radiomics features to construct a radiomics model; and the two models were fused to construct a spatial radiomics model. The efficacy of spatial radiomics model, spatial model, and radiomics model to discriminate PA from GG was analyzed using receiver operating characteristic curves and area under the curve (AUC). The generalization ability of the model was assessed by the difference in accuracy between the test sets and the validation sets (ΔACC). The clinical utility of the model was compared using clinical decision curves and calibration curves. Results:The statistical parametric mapping of lesions showed that supratentorial PA was vulnerable to medial structure areas such as suprasellar region, thalamus, basal ganglia and frontal lobe, temporal lobe, parietal lobe. GG was mainly distributed in bilateral temporal lobes, as well as frontal lobe, occipital lobe and parietal lobe. The AUCs of spatial radiomics model, radiomics model and spatial model to identify PA and GG in the test set were 0.876, 0.785, and 0.819, with accuracies of 77.59%, 72.41%, and 77.14%, respectively, and ΔACCs in the test set and validation set were 11.6%, 15.43%, and 6.94%, respectively. The clinical decision curves showed an overall greater clinical benefit of the spatial radiomics model compared with the conventional radiomics model and spatial model.Conclusion:Spatial radiomics model containing spatial information on lesion location can improve the diagnostic efficacy of supratentorial PA and GG, and enhance the generalization of the prediction model.
3.A controlled study on the impacts of different scanning protocols on image quality and radiation dose in chest CT
Chulin XU ; Wentao MA ; Yongxian ZHANG ; Yunfu LIU ; Tianliang KANG ; Senlin GUO ; Yantao NIU
Chinese Journal of Radiological Medicine and Protection 2024;44(9):789-796
Objective:To explore and compare the impacts of different scanning protocols on image quality and radiation dose in chest computed tomography (CT) scans.Methods:A retrospective analysis was conducted for the data of 65 randomly selected patients who underwent chest CT scans using a tube voltage of 120 kV, the automatic modulation technique for tube current, and z-axis radiation dose modulation at the Emergency Department of our hospital from June to July 2023. The enrolled cases were divided into two groups: the high-resolution group ( n = 34) and the conventional group ( n = 31), with the settings for scanning protocols identical to those for phantom scans. For patients in both groups, thin-layer images of the cross-sections in the lung and mediastinal windows were reconstructed using thickness/intervals of 1 mm/1 mm and 2 mm/1 mm, respectively. Meanwhile, high-resolution and conventional CT scans were conducted using a Catphan500 phantom under a tube voltage of 120 kV and a tube current of 150 mAs. Of both scanning protocols, the high-resolution CT scan utilized the lung nodule-orientated scanning mode, pitch of 1.5, and a detector combination providing a collimation of 16 × 0.75 mm. In contrast, the conventional CT scan was performed using the body-orientated scanning mode, pitch of 0.813, and a detector combination providing a collimation of 16 × 1.5 mm. Then, the high-contrast resolutions of the phantom images obtained using the two scanning protocols were objectively evaluated. Both coronal chest images in the lung window and cross-sectional images in the mediastinal window were reconstructed with a thickness/interval of 5 mm/5 mm for both groups. Then, the obtained images were imported into the Radimetrics system to compare the body size-specific dose estimation (SSDE), doses to sensitive organs on the body surface, and scanning time of both groups. For the cross-sectional images in the mediastinal window, the contrast-noise-ratio (CNR), signal-to-noise ratio (SNR), and figure-of-merit (FOM) were measured and calculated at the fixed anatomical parts. For the cross-sectional images in the lung window, their quality was subjectively evaluated by two senior diagnostic radiologists. Results:The result of phantom scans indicated that high-resolution CT scans yielded images with an approximately 5% increase in the spatial resolution in the xy-plane and a nearly 20% increase in the spatial resolution along the z-axis compared to conventional CT scans. The result of clinical data demonstrated that the conventional group exhibited significantly higher doses to the thyroid and the female breast ( t = 2.8, 2.3, P < 0.05), along with notably elevated SNR, CNR, and FOM values of the right trapezius, compared to the high-resolution group ( t = 4.1, 5.8, z=4.4, P < 0.001). However, the high-resolution group manifested significantly higher SNR, CNR, and FOM values of the thoracic aorta compared to the conventional group ( t = 3.4, 4.4, z=3.4, P < 0.001). In addition, the cross-sectional and coronal images in the lung window of the clinical cases in the high-resolution group exhibited more stable quality, with subjective scores exceeding 4 and the average scores of both groups not statistically significantly different. Conclusions:For chest CT examination, high-resolution CT scans are more suitable for observations focusing on the details of the lungs and mediastinum, while conventional CT is more suitable for those centering on soft tissues on the body surface.
4.Expert knowledge-based strategies for ventilator parameter setting and stepless adaptive adjustment.
Yongyan WANG ; Songhua MA ; Tianliang HU ; Dedong MA ; Xianhui LIAN ; Shuai WANG ; Jiguo ZHANG
Journal of Biomedical Engineering 2023;40(5):945-952
The setting and adjustment of ventilator parameters need to rely on a large amount of clinical data and rich experience. This paper explored the problem of difficult decision-making of ventilator parameters due to the time-varying and sudden changes of clinical patient's state, and proposed an expert knowledge-based strategies for ventilator parameter setting and stepless adaptive adjustment based on fuzzy control rule and neural network. Based on the method and the real-time physiological state of clinical patients, we generated a mechanical ventilation decision-making solution set with continuity and smoothness, and automatically provided explicit parameter adjustment suggestions to medical personnel. This method can solve the problems of low control precision and poor dynamic quality of the ventilator's stepwise adjustment, handle multi-input control decision problems more rationally, and improve ventilation comfort for patients.
Humans
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Ventilators, Mechanical
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Respiration, Artificial
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Neural Networks, Computer
5.Study on the effect of virtual grid on chest X-ray image quality
Tianliang KANG ; Yunfu LIU ; Yongxian ZHANG ; Senlin GUO ; Wentao MA ; Yantao NIU
Chinese Journal of Radiology 2023;57(5):547-552
Objective:To explore the image quality and its evaluation method using virtual grid under different tube voltages in the clinical chest X-ray exam.Methods:According to the conditions of chest X-ray photography commonly used in clinical practice, the corresponding thickness of plexiglass (20 cm, including CDRAD phantom) was determined as the experimental object. With a fixed tube loading of 4 mAs and the tube voltage from 60 to 125 kV, the experimental object was imaged in three ways: physical grid, none grid and virtual grid. The common physical parameters (CNR, σ, C, SNR), texture analysis (Angular second moment, texture Contrast, Correlation, Inverse difference moment, Entropy) and CDRAD phantom score (IQF inv) were evaluated. Two-way ANOVA test was used for each group of common physical parameters, and further pairwise comparisons were made. At the same time, applying virtual grids on the obtained images with chest anthropomorphic model and texture indexing the images with and without virtual grids, then rank sum test of paired sample can be conducted. Results:There were differences in image quality among the three groups of grid mode( P<0.05), and the physical grid delivered the best image quality. The tube voltage had an impact on all image quality evaluation indexes ( P<0.05). The tube voltage was positively correlated with CNR, SNR, angular second moment, inverse difference moment and IQF inv ( P<0.05), and negatively correlated with σ, C, texture contrast and entropy ( P<0.05). There was no significant correlation between the tube voltage and Correlation ( P>0.05). The chest anthropomorphic model images were used to evaluate the virtual grids, and the texture indexes (Angle second moment, Contrast, Correlation, Inverse difference moment, Entropy) were statistically significant (P<0.05). Conclusions:The virtual grid can improve the image quality of chest X-ray photography, and the image texture analysis method can be a useful supplement to the image quality evaluation parameters.
6.The effect of CT detector width and signal acquisition positions on image quality
Senlin GUO ; Yue REN ; Yongxian ZHANG ; Tianliang KANG ; Yunfu LIU ; Lei ZHU ; Yantao NIU
Chinese Journal of Radiology 2023;57(6):684-688
Objective:To evaluate the influence of different detector widths and signal acquisition positions of wide-detector CT in different scanning modes on CT number and noise, and to provide a basis for reasonable selection of scanning modes and related parameters in clinical practice.Methods:The body dose phantom was scanned by GE Revolution CT. The scan was performed with detector widths of 40, 80 and 160 mm in sequential scanning mode and with detector width/pitch combinations of 40 mm/0.516, 40 mm/0.984, 80 mm/0.508 and 80 mm/0.992 in spiral scanning mode. The phantom was placed at the central and peripheral of the selected detector widths, and the adjacent positions between two axial scans. The images of the phantom were evaluated subjectively and the CT numbers and SDs were measured. The differences between the measured values at different imaging parameters were compared. The multi-group Friedman test was used to compare CT numbers and SD under different scanning parameters in sequential scanning mode, and the Wilcoxon test was used to compare CT numbers and SD in spiral scanning mode.Results:There was no statistically significant difference in the geometric shapes of the phantom images obtained at any combination of parameters. In sequential scanning mode, the differences at different detector widths were statistically significant (χ 2=14.00, P=0.001) with CT numbers at 40 mm and 160 mm greater than CT numbers at 80 mm ( P<0.05). The differences at different signal acquisition positions were statistically significant (χ 2=12.04, P=0.002) with CT numbers at peripheral and adjacent greater than CT numbers at central ( P<0.05). In spiral scanning mode CT numbers at detector width at 80 mm were greater than CT numbers at 40 mm ( Z=-2.10, P=0.036). For SD, the differences at different detector widths were statistically significant in sequential scanning modes (χ 2=8.17, P=0.017) with SD at 160 mm greater than SD at 80 mm ( P<0.05). The differences at different signal acquisition positions were statistically significant (χ 2=13.50, P=0.001) with SD at peripheral greater than SD at central ( P<0.05). In spiral scanning mode SDs at pitches 0.984 and 0.992 were greater than SDs at 0.516 and 0.508 ( Z=-2.66, P=0.008). There were no significant differences among other groups. Conclusion:The selection of scanning mode, detector width and signal acquisition position of wide-detector CT will affect the image CT numbers and SDs.
7.Effect of neck CT arteriovenous simultaneous enhancement methods on image quality and radiation dose
Yunfu LIU ; Tianliang KANG ; Yongxian ZHANG ; Senlin GUO ; Lin FU ; Qinggang XU ; Yingying CAO ; Junfang XIAN ; Yantao NIU
Chinese Journal of Radiology 2023;57(7):756-761
Objective:To investigate the feasibility of simultaneous arteriovenous enhancement of neck CT with two-stage injection of contrast agent and its effect on image quality and radiation dose.Methods:A total of 30 patients undergoing neck CT enhancement scan due to space-occupying lesions in Beijing Tongren Hospital, Capital Medical University from February to April 2022 were prospectively included as the experimental group. The neck CT enhancement scan was performed with two-stage injection of contrast agent and arteriovenous simultaneous enhancement. The dosage of contrast agent was calculated according to the patient′s body weight, and the method of two-stage injection was adopted. The dosage of contrast agent in the first stage was 0.7 ml/kg, with normal saline in the middle stage, and the second stage (began at 35 s) was 0.3 ml/kg. A total of 30 patients with gender and age matching with the experimental group from December 2021 to January 2022 were retrospectively collected as the control group. The control group was treated with the traditional arterial phase and venous phase scanning method with the dosage of 1.0 ml/kg contrast agent. The arterial phase was scanned at the 30 s and the venous phase was scanned at the 60 s. The CT values of bilateral carotid arteries and jugular veins in the experimental group were measured, the CT values of bilateral carotid arteries in the arterial phase were measured in the control group, and the CT values of bilateral carotid arteries and jugular veins in the venous phase were measured. Carotid artery enhancement score was performed for images of experimental group and control group in arterial and venous phase, and jugular vein and lesion enhancement score was performed for images of experimental group and control group in venous phase. The effective dose was calculated for both groups. The difference of carotid artery CT values between images was compared by one-way analysis of variance, and LSD method was used for pairwise comparison. The CT values of jugular vein were compared using independent sample t test. Kruskal-Wallis test was used to compare carotid artery enhancement scores, and Nemenyi method was used for pairwise comparison. Jugular vein and lesion enhancement scores and effective dose were compared by Mann-Whitney U test. Results:The CT value of carotid artery of experimental group [left (276±24) HU, right (273±25) HU] was lower than that of control group in arterial phase [left (329±33) HU, right (327±32) HU], and higher than that in the venous phase [left (147±15) HU, right (148±16) HU]. All the differences were statistically significant ( P<0.001). The CT value of jugular vein of experimental group [left (206±18) HU, right (203±19)] was higher than that of control group in the venous phase [left (154±15) HU, right (151±15)], the difference was statistically significant ( t=11.88, 11.76, both P<0.001). There was no significant difference in carotid artery enhancement score between experimental group and control group in arterial phase ( P=0.624), but the carotid artery enhancement score of the experimental group was higher than that of the control group in the venous phase, and the difference was statistically significant ( P<0.001). The scores of jugular vein and lesion enhancement in experimental group were higher than those of control group in venous phase, and the difference was statistically significant ( Z=5.01, P<0.001). The effective dose of the experimental group [2.41(2.04, 2.72) mSv] was decreased by 52.2% compared with the control group [5.04(4.18, 5.44) mSv], and the difference was statistically significant ( Z=-6.24, P<0.001). Conclusions:The neck CT enhanced scan with two-stage injection of contrast agent and arteriovenous simultaneous enhancement method can obtain comprehensive images of arterial and venous phases, and realize simultaneous enhancement of carotid artery, jugular vein and lesions, and reduce radiation dose.
8.Fingertip reconstruction with V-Y advancement flap and nailbed suture following Allen’s type Ⅲ amputation: a report of 16 cases
Yiming LU ; Bin WANG ; Tianliang WANG ; Yang WANG ; Jiaxiang GU ; Naichen ZHANG
Chinese Journal of Plastic Surgery 2023;39(8):868-872
Objective:To discuss the effect of fingertip reconstruction with V-Y advancement flap and nailbed suture treating Allen’s type Ⅲ amputations unsuitable for vascular anastomosis.Methods:From September 2018 to December 2020, clinical data of patients with Allen’s type Ⅲ fingertip amputations treated in Northern Jiangsu People’s Hospital were analyzed retrospectively. The fingertips were reconstructed with V-Y advancement flap and nailbed suture. The infeasibility of vascular anastomosis was checked under the microscope. Following fixation of the distal phalanx, the nailbed was stretched as flat as possible and sutured. If the nail plate was missing, a manual nail plate made from a plastic transfusion pipe would be fixed to cover the exposed nailbed. The palmar soft tissue of the amputated fingertip was excised, and periosteum, hyponychium, nailbed, and dorsal soft tissue were retained. The proximal volar skin was incised until the subcutaneous adipose layer to get a V-Y advancement flap. The volar defect was repaired with the V-Y advancement flap distally sutured with the pre-retained hyponychium. Postoperatively, burn cream was smeared on the nail for moisturizing, without lamp heating, and intravenous antibiotics was administered routinely. The main indexes were collected including nail appearance, pulp plumpness, static two-point discrimination, motion loss of the distal interphalangeal joint, and patients’ self-evaluation of the appearance. Chinese Medical Association trial standard of upper limb partial function assessment (CMA evaluation) was used to evaluate finger function.Results:A total of 16 patients with 18 fingertips were included. There were 9 males and 7 females, aged (31.5±6.1) years (21-52 years). There were 14 cases of single fingertips injury and 2 cases of multiple fingertips injury. Damaged finger: 2 of thumb, 3 of indicator finger, 6 of middle finger, 5 of ring finger, 2 of little finger. All 18 fingertips survived postoperatively and followed up for 7-16 months (median 12 months). One case underwent a second surgery due to infection and mild bone exposure followed by good healing. One case had a slightly hooked nail. The fingertip appearance was satisfying or acceptable by all the patients except the above two. Good results were got for all patients such as bone healing, smooth nail, plump pulp, and flexible distal interphalangeal joint. At the latest follow-up, motion loss of the distal interphalangeal joint was 0°-3.6° (mean 2.4°) for extension and 2.0°-12.0° (mean 7.6°) for flexion. The static two-point discrimination was 2.5-4.6 mm (mean 3.8 mm). Respectively, the functional evaluation of the affected finger was excellent in 11 cases, good in 3 cases and fair in 2 cases according to the CMA evaluation.Conclusion:Fingertip reconstruction with V-Y advancement flap and nailbed suture is a good technique to treat Allen’s type Ⅲ amputations, with advantages of preserved fingertip length, smooth nail, plump pulp, good sensory and flexible distal interphalangeal joint. The technique is simple with a high success rate and good results.
9.Fingertip reconstruction with V-Y advancement flap and nailbed suture following Allen’s type Ⅲ amputation: a report of 16 cases
Yiming LU ; Bin WANG ; Tianliang WANG ; Yang WANG ; Jiaxiang GU ; Naichen ZHANG
Chinese Journal of Plastic Surgery 2023;39(8):868-872
Objective:To discuss the effect of fingertip reconstruction with V-Y advancement flap and nailbed suture treating Allen’s type Ⅲ amputations unsuitable for vascular anastomosis.Methods:From September 2018 to December 2020, clinical data of patients with Allen’s type Ⅲ fingertip amputations treated in Northern Jiangsu People’s Hospital were analyzed retrospectively. The fingertips were reconstructed with V-Y advancement flap and nailbed suture. The infeasibility of vascular anastomosis was checked under the microscope. Following fixation of the distal phalanx, the nailbed was stretched as flat as possible and sutured. If the nail plate was missing, a manual nail plate made from a plastic transfusion pipe would be fixed to cover the exposed nailbed. The palmar soft tissue of the amputated fingertip was excised, and periosteum, hyponychium, nailbed, and dorsal soft tissue were retained. The proximal volar skin was incised until the subcutaneous adipose layer to get a V-Y advancement flap. The volar defect was repaired with the V-Y advancement flap distally sutured with the pre-retained hyponychium. Postoperatively, burn cream was smeared on the nail for moisturizing, without lamp heating, and intravenous antibiotics was administered routinely. The main indexes were collected including nail appearance, pulp plumpness, static two-point discrimination, motion loss of the distal interphalangeal joint, and patients’ self-evaluation of the appearance. Chinese Medical Association trial standard of upper limb partial function assessment (CMA evaluation) was used to evaluate finger function.Results:A total of 16 patients with 18 fingertips were included. There were 9 males and 7 females, aged (31.5±6.1) years (21-52 years). There were 14 cases of single fingertips injury and 2 cases of multiple fingertips injury. Damaged finger: 2 of thumb, 3 of indicator finger, 6 of middle finger, 5 of ring finger, 2 of little finger. All 18 fingertips survived postoperatively and followed up for 7-16 months (median 12 months). One case underwent a second surgery due to infection and mild bone exposure followed by good healing. One case had a slightly hooked nail. The fingertip appearance was satisfying or acceptable by all the patients except the above two. Good results were got for all patients such as bone healing, smooth nail, plump pulp, and flexible distal interphalangeal joint. At the latest follow-up, motion loss of the distal interphalangeal joint was 0°-3.6° (mean 2.4°) for extension and 2.0°-12.0° (mean 7.6°) for flexion. The static two-point discrimination was 2.5-4.6 mm (mean 3.8 mm). Respectively, the functional evaluation of the affected finger was excellent in 11 cases, good in 3 cases and fair in 2 cases according to the CMA evaluation.Conclusion:Fingertip reconstruction with V-Y advancement flap and nailbed suture is a good technique to treat Allen’s type Ⅲ amputations, with advantages of preserved fingertip length, smooth nail, plump pulp, good sensory and flexible distal interphalangeal joint. The technique is simple with a high success rate and good results.
10.Bispecific prodrug nanoparticles circumventing multiple immune resistance mechanisms for promoting cancer immunotherapy.
Jiayi YE ; Bo HOU ; Fangmin CHEN ; Shunan ZHANG ; Muya XIONG ; Tianliang LI ; Yechun XU ; Zhiai XU ; Haijun YU
Acta Pharmaceutica Sinica B 2022;12(6):2695-2709
Cancer immunotherapy is impaired by the intrinsic and adaptive immune resistance. Herein, a bispecific prodrug nanoparticle was engineered for circumventing immune evasion of the tumor cells by targeting multiple immune resistance mechanisms. A disulfide bond-linked bispecific prodrug of NLG919 and JQ1 (namely NJ) was synthesized and self-assembled into a prodrug nanoparticle, which was subsequently coated with a photosensitizer-modified and tumor acidity-activatable diblock copolymer PHP for tumor-specific delivery of NJ. Upon tumor accumulation via passive tumor targeting, the polymeric shell was detached for facilitating intracellular uptake of the bispecific prodrug. NJ was then activated inside the tumor cells for releasing JQ1 and NLG919 via glutathione-mediated cleavage of the disulfide bond. JQ1 is a bromodomain-containing protein 4 inhibitor for abolishing interferon gamma-triggered expression of programmed death ligand 1. In contrast, NLG919 suppresses indoleamine-2,3-dioxygenase 1-mediated tryptophan consumption in the tumor microenvironment, which thus restores robust antitumor immune responses. Photodynamic therapy (PDT) was performed to elicit antitumor immunogenicity by triggering immunogenic cell death of the tumor cells. The combination of PDT and the bispecific prodrug nanoparticle might represent a novel strategy for blockading multiple immune evasion pathways and improving cancer immunotherapy.

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