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Synthesis of coronary 4D CT Image by denoising diffusion probabilistic model

Sat, 01 Aug 2026 00:00:00 GMT

Title: Synthesis of coronary 4D CT Image by denoising diffusion probabilistic model Authors: Han, Tae Ho; Kim, Young Woo; Lee, Hyeong Jun; Kim, Jung-Sun; Lee, Seul-Gee; Yang, Dong Hyun; Oh, Hong Min; Kim, Doosang; Shin, Seung Yong; Song, Simon; Lee, Joon Sang Abstract: Purpose: Fluctuations in the pressure drop during the cardiac cycle can provide prognostic information for coronary artery disease (CAD). However, 4D computed tomography (CT) is required for time-variant flow analysis, which results in high doses of radiation exposure. In this study, we propose a novel diffusion-based framework for synthesizing physiologically consistent 4D CT images and performing 4D CT flow analysis. Methods: A denoising diffusion probabilistic model (DDPM) integrated with a deformation module was used for precise anatomical reconstruction. Subsequently, a computational fluid dynamics (CFD) model coupled with quasi-steady fluid-structure interaction (FSI) was utilized to calculate the 4D hemodynamic flow field. Results: The model achieved a peak signal-to-noise ratio of 32.01 and a structural similarity index measure of 0.937. After 3D construction and segmentation, the average Dice coefficient was 0.973. Furthermore, the computational fluid analysis was also performed with a fractional flow reserve (FFR) accuracy of 90.5%, demonstrating its efficacy in reducing radiation exposure without compromising diagnostic quality. Conclusion: Our results demonstrate that this synthesized 4D CT-based hemodynamic approach provides timevariant information for CAD diagnosis. This method offers valuable guidance for clinical decision-making as well as the possibility of prognostic information based on dynamic lumen evaluation.

Interplay of age-sensitive cortical vulnerability and dopaminergic degeneration in clinical manifestations of Parkinson's disease

Wed, 01 Jul 2026 00:00:00 GMT

Title: Interplay of age-sensitive cortical vulnerability and dopaminergic degeneration in clinical manifestations of Parkinson's disease Authors: Kang, Sungwoo; Na, Han Kyu; Yoon, So Hoon; Kim, Han-Kyeol; Ryu, Young Hoon; Lee, Hye Sun; Yoo, Han Soo; Lyoo, Chul Hyoung; 유한수 Abstract: To identify the pattern of cortical atrophy variation in Parkinson's disease (PD) and its contribution to clinical manifestations beyond dopaminergic dysfunction, 45 healthy controls (HCs) underwent MRI, and 222 participants with PD additionally underwent dopamine transporter (DAT)-PET, Unified PD Rating Scale (UPDRS), and neuropsychological tests. Using principal component analysis in PD, a single pattern in cortical thickness (PC1PD) was identified. Linear regressions models were applied to investigate the effects of PC1PD and putaminal DAT (DAT-P) on parkinsonism, and PC1PD and caudate DAT (DAT-C) on cognition. PC1PD accounted for more than 80% of total cortical variance and showed a strong negative correlation with age. The spatial pattern of PC1PD was similar to that of PC1 derived from HCs, but its age-related association was more pronounced in PD. Independent of DAT-P, lower PC1PD was associated with higher UPDRS motor score and showed a synergistic significant interaction with DAT-P on the axial subscore. Independent of DAT-C, lower PC1PD was associated with worse performance in global cognition, language, and executive functions, with synergistic interaction with DATC on global cognition and executive function. The associations of PC1PD with UPDRS motor scores, general cognition, and executive function were stronger in older participants, indicating that aging amplifies the clinical effect of PC1PD. PC1PD represents an age-sensitive cortical vulnerability axis whose expression is amplified in PD, and its interplay with dopaminergic depletion and aging contributes to axial motor symptoms and executive dysfunction in PD.

Mechanisms underlying the effect of nurse-led enhanced supportive care for advanced cancer patients: A mediation analysis of randomized controlled trial data

Mon, 01 Jun 2026 00:00:00 GMT

Title: Mechanisms underlying the effect of nurse-led enhanced supportive care for advanced cancer patients: A mediation analysis of randomized controlled trial data Authors: Hong, Bomi; Choi, Yun Young; Lee, Hye Sun; Lee, Jiyeon Abstract: Purpose: A nurse-led enhanced supportive care intervention integrating the Bandura's mastery enhancement and the acceptance and commitment therapy approach as an early primary palliative care was effective in improving coping, self-efficacy for coping with cancer, and role functioning. This study examined the mechanisms through which the intervention improved role functioning in patients with advanced cancer, focusing on the mediating roles of coping and self-efficacy for coping with cancer. Methods: A secondary analysis was conducted (N = 182). Active coping, self-efficacy for maintaining activity and independence, and role functioning were measured using the Brief COPE, the Cancer Behavior Inventory 3.0, and the EORTC QLQ-C30. Descriptive, correlation, and mediation analyses were conducted using IBM SPSS 27 and PROCESS macro Models 4 and 6. Results: In the serial mediation analysis, the intervention demonstrated statistically significant total effect on role functioning (effect = 8.89, SE = 3.21, 95% CI [2.54, 15.23]). The direct effect of the intervention remained significant after accounting for active coping and self-efficacy in maintaining activity and independence as mediators (effect = 6.19, SE = 3.08, 95% CI [0.12, 12.27]). The sequential pathway suggested by the conceptual model was statistically significant (effect = 0.78, SE = 0.46, 95% CI [0.11, 1.90]) and explained 8.8% of the total effect. Conclusion: The nurse-led enhanced supportive care improved role functioning via the serial mediation of active coping and self-efficacy for maintaining activity and independence. The results highlight the importance of coping and self-efficacy in enhancing role functioning and provide direction for future palliative care interventions. Trial registration: NCT04407013.

Precipitation-based versus filtration-based liquid-based cytology in endoscopic ultrasound-FNB specimens of solid pancreatic masses: a prospective, randomized trial(with video)

Mon, 01 Jun 2026 00:00:00 GMT

Title: Precipitation-based versus filtration-based liquid-based cytology in endoscopic ultrasound-FNB specimens of solid pancreatic masses: a prospective, randomized trial(with video) Authors: Lee, See Young; Nahm, Ji Hae; Jung, Chan Min; Jo, Jung Hyun; Kim, Hyung Sun; Seong, Yeseul; Lee, Hye Sun; Jeon, Soyoung; Jang, Sung Ill; Cho, Jae Hee Abstract: Background and Aims EUS-guided fine-needle biopsy (FNB) is the standard technique for diagnosing solid pancreatic masses, offering high histologic accuracy. However, adequate tissue acquisition can still be difficult in small or technically demanding lesions. Liquid-based cytology (LBC) may serve as a complementary tool to improve diagnostic yield. This study compared the diagnostic efficacy and cytomorphologic features of 2 LBC techniques—precipitation-based SurePath and filtration-based ThinPrep—using cytologic specimens prepared from the residual fluid remaining after retrieval of core tissue from EUS-FNB specimens. Methods A total of 102 patients with suspected malignant pancreatic tumors who underwent EUS-guided FNB were prospectively randomized into the SurePath and ThinPrep groups in a 1:1 ratio. Cytomorphologic features and slide quality were systematically evaluated. The final diagnosis integrated the cytologic, histologic, and clinical follow-up results. Results The groups had comparable baseline characteristics. Most cases (99.02%) were diagnosed as malignant, and pancreatic ductal adenocarcinoma was predominant (90.20%). SurePath demonstrated superior diagnostic accuracy (97.0% vs 83.9%, P = .002) and sensitivity (97.0% vs 83.7%, P = .002) to ThinPrep, whereas both techniques showed 100% specificity and positive predictive values. SurePath required a significantly shorter interpretation time ( P = .023). Cytomorphologically, SurePath showed more even distributions ( P < .001) and 3-dimensional clusters ( P < .001) and less cytoplasmic blurring ( P = .064). SurePath preparations also demonstrated better preservation of key diagnostic features, including conspicuous nucleoli ( P = .013), hyperchromasia ( P = .035), and coarse chromatin ( P = .009). SurePath achieved greater cellularity than ThinPrep, with 18.6% and 0% of cases, respectively, showing very high cellularity ( P < .001). Conclusions For EUS-guided FNB of solid pancreatic masses, the SurePath LBC technique demonstrated superior diagnostic performance, faster interpretation times, and better preservation of cytomorphologic features than ThinPrep. These findings suggest that SurePath should be the preferred LBC method for evaluating EUS-guided FNB of pancreatic masses. (Clinical trial registration number: KCT0006748). © 2025 American Society for Gastrointestinal Endoscopy.