Japanese Journal of Radiology最新文献

{"title":"Correlation of tumor maximum standardized uptake value from ¹⁸F-BPA PET and boron neutron capture therapy tumor dose with treatment outcomes in head and neck cancer: a retrospective analysis.","authors":"Yuki Yoshino, Satoshi Takeno, Teruhito Aihara, Kayako Isohashi, Naonori Hu, Yasukazu Kanai, Akinori Sasaki, Mai Nojiri, Tetsuya Terada, Shinichi Haginomori, Keiji Nihei, Koji Ono","doi":"10.1007/s11604-026-02020-7","DOIUrl":"10.1007/s11604-026-02020-7","url":null,"abstract":"<p><strong>Purpose: </strong>Boron neutron capture therapy (BNCT) dose planning conventionally uses a tumor-to-blood (T/B) ratio derived from the tumor maximum standardized uptake value (SUVmax) of fluorine-18-labeled 4-borono-L-phenylalanine (¹⁸F-BPA) positron emission tomography (PET) (individual model). It remains unclear whether tumor SUVmax or individual model doses predict outcomes in accelerator-based BNCT for head and neck cancer (HNC). We investigated the correlation of ¹⁸F-BPA PET SUVmax and individual model doses with treatment response.</p><p><strong>Materials and methods: </strong>We retrospectively analyzed 30 patients with HNC treated with accelerator-based BNCT (2020-2021). The Kaplan-Meier method was used for survival analysis. Dose parameters (Dmax, Dmin, and D80%) were calculated using the uniform model (T/B = 2.5) and the individual model (T/B = Tumor SUVmax/Blood-pool SUV). Correlations between tumor SUVmax or dose parameters and best treatment response [complete response (CR) vs. non-CR] were evaluated using the Mann-Whitney U test.</p><p><strong>Results: </strong>The objective response rate was 90%, and the CR rate was 50%. CR status strongly predicted superior 2 years overall survival, locoregional control, and progression-free survival (all p < 0.05). However, no significant differences were observed between the CR and non-CR groups for tumor SUVmax, uniform model doses, or individual model doses (all p > 0.05).</p><p><strong>Conclusion: </strong>¹⁸F-BPA PET SUVmax and the conventional individual model did not demonstrate a statistically significant association with CR in patients with HNC after accelerator-based BNCT. These findings question the utility of tumor SUVmax-based dosimetry, suggesting that current models require refinement.</p>","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":"1845-1853"},"PeriodicalIF":2.1,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13623982/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148143289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent advances in MR neuroimaging: toward quantitative and AI-driven brain and spinal cord imaging.","authors":"Xunyang Zhang, Akifumi Hagiwara, Masaya Takahasi, Koji Kamagata, Masaaki Hori","doi":"10.1007/s11604-026-02037-y","DOIUrl":"10.1007/s11604-026-02037-y","url":null,"abstract":"<p><p>Magnetic resonance neuroimaging is undergoing a major paradigm shift from traditional qualitative anatomical mapping toward integrated, quantitative measurement systems with biological interpretability. This review systematically synthesizes nine methodological pillars driving this transformation, encompassing advances ranging from hardware innovation to artificial intelligence algorithms. We first explore the pivotal role of deep learning in image reconstruction and acceleration, followed by detailed analyses of quantitative brain oxygen metabolism assessment, standardized spinal cord imaging frameworks, and the non-invasive monitoring of the glymphatic system using diffusion MRI. Furthermore, the review delves into tractometry, susceptibility-based myelin mapping, the clinical standardization of arterial spin labeling, and the application of radiomics in extracting high-dimensional phenotypes. Finally, the importance of open science and workflow coordination in enhancing research reproducibility is highlighted. Through the deep integration of hardware, sequences, and artificial intelligence, these technologies form a synergistic ecosystem that provides unprecedented precision tools and translational potential for both basic neuroscience research and clinical precision medicine. Across these domains, AI contributes not only to acceleration and reconstruction but also to segmentation, quality control, quantitative parameter extraction, and multiparametric pattern recognition that can support diagnostic interpretation. The quantitative emphasis of this review therefore lies in measurable outputs such as image-quality metrics, metabolic and perfusion parameters, tract-specific diffusion indices, susceptibility-based components, and radiomic features.</p>","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":"1726-1744"},"PeriodicalIF":2.1,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148828609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"LR-TR viable as an early imaging indicator of local recurrence after radiofrequency ablation for hepatocellular carcinoma: a longitudinal assessment using LI-RADS nonradiation TRA version 2024.","authors":"Yu-Hsin Chen, Wei-Chou Chang, Yu-Lueng Shih, Hsuan-Hwai Lin, Chang-Hsien Liu, Sung-Hua Chiu","doi":"10.1007/s11604-026-02075-6","DOIUrl":"https://doi.org/10.1007/s11604-026-02075-6","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate longitudinal changes of LR-TR Viable observations after radiofrequency ablation (RFA) and characterize their temporal relationship with fulfillment of operational imaging criteria for local recurrence of HCC.</p><p><strong>Materials and methods: </strong>This single-institution retrospective study enrolled treatment-naïve HCC patients who underwent RFA as first-line treatment between 2017 and 2024. Baseline HCC was diagnosed by LR-4/LR-5 categorization according to the LI-RADS CT/MRI Diagnostic Algorithm Version 2018 (LI-RADS Diagnostic v2018) in at-risk patients or by histopathology. Two radiologists chronologically reviewed post-RFA CT/MRI examinations using the LI-RADS CT/MRI Nonradiation Treatment Response Algorithm Version 2024 (LI-RADS Nonradiation TRA v2024) and LI-RADS Diagnostic v2018, with disagreements resolved by a third senior radiologist. An operational imaging endpoint for local recurrence was defined as an ablation-margin assignment of LR-4, LR-5, LR-M, or LR-TIV according to LI-RADS Diagnostic v2018, although this algorithm was originally developed for untreated observations.</p><p><strong>Results: </strong>A total of 127 patients (median age, 68 years [IQR, 61-74 years]; 87 men, 40 women) with 136 HCC lesions were evaluated across 606 post-RFA lesion-level assessments. During follow-up, 70 lesions (51.5%) were categorized as LR-TR Viable at least once; 64 (91.4%) concurrently or subsequently fulfilled the operational imaging criteria for local recurrence. Among these 64 lesions, 21 (32.8%) had not yet met the criteria at initial LR-TR Viable assignment but did so during subsequent follow-up. In these 21 lesions, the median interval to criteria fulfillment was 5.0 months (IQR, 4.4-13.0). Lesions were smaller at initial LR-TR Viable assignment than at the subsequent examination meeting the operational imaging criteria (1.3 cm versus 2.0 cm; p < 0.001).</p><p><strong>Conclusion: </strong>LR-TR Viable assignment preceded fulfillment of the operational LI-RADS Diagnostic v2018 imaging criteria for local recurrence in approximately one-third of lesions, with a smaller lesion size at initial assignment than at subsequent criteria fulfillment.</p>","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149030595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reproducibility of a quantitative body diffusion score derived from whole-body diffusion-weighted imaging (DWIBS) for assessment of bone metastases in prostate cancer.","authors":"Katsuyuki Nakanishi, Yasuhiro Nakaya, Junichiro Tanaka, Hidenari Hongyo, Noboru Maeda, Mio Sakai, Nobuo Kashiwagi, Akira Nagahara, Masashi Nakayama, Kazuo Nishimura, Noriyuki Tomiyama","doi":"10.1007/s11604-026-02077-4","DOIUrl":"10.1007/s11604-026-02077-4","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate whether changes in diffusion-based total lesion volume (ΔtDV) on whole-body MRI correlate with changes in serum prostate-specific antigen (ΔPSA) after therapy, and to assess reproducibility of ΔtDV measurements.</p><p><strong>Materials and methods: </strong>This retrospective study included 20 prostate cancer patients who underwent whole-body MRI before and after treatment. Changes in total lesion volume (ΔtDV), mean apparent diffusion coefficient (ΔmADC), and PSA (ΔPSA) were calculated. Correlations between ΔtDV and ΔPSA, as well as between ΔmADC and ΔPSA, were evaluated using Spearman's rank correlation coefficient. Image interpretation was independently performed by two readers blinded to clinical information. One reader conducted two separate reading sessions with an approximately one-year washout period. Inter-observer and intra-observer agreement for ΔtDV measurements was assessed using Bland-Altman analysis and intraclass correlation coefficients (ICCs).</p><p><strong>Results: </strong>ΔtDV demonstrated a strong positive correlation with ΔPSA across all three reader sessions, with Spearman correlation coefficients exceeding 0.7 and significant p values (p < 0.05). In contrast, ΔmADC showed a weak negative correlation with ΔPSA, which did not reach statistical significance. Bland-Altman analysis showed mean biases of -3.1 mL for inter-observer measurements and 1.4 mL for intra-observer measurements, with 95% limits of agreement of -22.6 to 16.5 mL and -19.0 to 21.9 mL, respectively. The inter- and intra-observer ICCs were 0.916 and 0.911, respectively, indicating excellent agreement.</p><p><strong>Conclusion: </strong>Changes in diffusion-based total lesion volume on whole-body MRI show a strong and reproducible association with PSA changes after therapy, suggesting that ΔtDV may serve as a robust quantitative imaging biomarker for treatment response in prostate cancer bone metastases.</p>","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149030628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Persistent postural-perceptual dizziness (PPPD): the most common cause of chronic dizziness.","authors":"Arata Horii, Chihiro Yagi, Akira Kimura","doi":"10.1007/s11604-026-02082-7","DOIUrl":"https://doi.org/10.1007/s11604-026-02082-7","url":null,"abstract":"<p><p>Persistent postural- perceptual dizziness (PPPD) is a functional disorder that is the most frequent cause of chronic dizziness. Diagnostic criteria for PPPD were published by Bárány Society in 2017 and were then included in the International Classification of Diseases, 11th revision (ICD-11). Core symptoms are dizziness, unsteadiness or non-spinning vertigo, lasting more than three months. Persistent symptoms occur without specific provocation, but are exacerbated by upright posture/walking, active or passive motion, and exposure to moving or complex visual stimuli. An acute or episodic vestibular disorder often precedes the onset of PPPD, but conventional vestibular function tests typically show normal results. Studies using resting-state functional MRI have revealed that functional connectivity between the vestibular cortex and visual areas were low, while that between the somatosensory and visual areas was high, suggesting sensory upweighting of visual and somatosensory information. Such central changes have been shown to associate with peripheral hyper-responsiveness as demonstrated by visual stimulus-loaded posturography and head-roll tilt subjective visual vertical testing, which detects visual and neck proprioceptive hypersensitivity, respectively. As a result, symptoms are exacerbated by visual stimulation or somatosensory input associated with body motion. After visual stimulation, gaze stability remains reduced, which would account for the prolonged dizziness induced by visual stimuli. Pharmacological treatments using serotonergic anti-depressants, vestibular rehabilitation, and cognitive behavioral therapy have been shown favorable effects; however, they are not always effective for all patients. There is an urgent need to establish novel treatments tailored to the pathophysiology of PPPD, i.e., sensory upweighting of visual/somatosensory inputs.</p>","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149030597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Technical feasibility of AI-based longitudinal multi-organ volumetry on low-dose PET/CT over 13 years.","authors":"Rika Kobayashi, Tetsuro Sekine, Shogo Imai, Koji Sohara, Takahiro Ando, Aruki Tanaka, Nahiro Yan, Hiromitsu Hayashi, Shin-Ichiro Kumita","doi":"10.1007/s11604-026-02079-2","DOIUrl":"https://doi.org/10.1007/s11604-026-02079-2","url":null,"abstract":"<p><strong>Purpose: </strong>This study aimed to (i) compare TotalSegmentator Fast and Normal inference modes on low-dose PET/CT, (ii) evaluate whether CT denoising improves segmentation longitudinal consistency, and (iii) examine whether the selected pipeline can capture long-term within-participant volumetric trends over approximately 13 years.</p><p><strong>Materials and methods: </strong>This retrospective study drew from a PET/CT screening registry of 15,597 examinees. In Phase 1, 10 participants (137 scans) were selected for pipeline optimization: Fast versus Normal modes and five denoising methods were compared using detrended within-participant CV. In Phase 2, 30 participants aged ≥60 years (337 scans) were analyzed. Volumetric changes in six structures were modeled using a linear mixed-effects model with false discovery rate correction.</p><p><strong>Results: </strong>Fast mode demonstrated similar detrended longitudinal variability to Normal mode across the six analyzed structures (detrended CV range: 2.26-9.32%), with approximately 10-fold faster processing. No tested denoising method meaningfully improved the selected serial-variability metrics over raw CT. In the primary random-intercept model, all six structures showed significant population-average volumetric trends (all p < 0.001, FDR q < 0.001): autochthon (paraspinal) muscles (- 0.72%/year), iliopsoas (- 0.74%/year), liver (- 0.55%/year), kidneys (- 0.49%/year), pancreas (- 0.97%/year), and aorta (+ 0.94%/year). In the random-slope sensitivity analysis, all six structures-including the iliopsoas and aorta-remained statistically significant (all RS p < 0.01) when individual trajectory slopes were accommodated.</p><p><strong>Conclusion: </strong>Fast mode on raw low-dose PET/CT provided the most favorable speed-stability trade-off for TotalSegmentator-based multi-organ volumetry. Long-term within-participant volumetric trends were detectable over a 13-year follow-up, supporting technical feasibility but not yet establishing biological attribution or clinical utility.</p>","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149030630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep learning model for the prediction of lymph node metastasis in esophageal squamous cell carcinoma using MIP FDG-PET images: a retrospective validation study.","authors":"Hiroki Maruyama, Kentaro Takanami, Eichi Takaya, Shinya Sonobe, Yoshitaka Toyama, Yusuke Taniyama, Chiaki Sato, Hiroshi Okamoto, Yohei Ozawa, Hirotaka Ishida, Kei Takase, Takashi Kamei","doi":"10.1007/s11604-026-02084-5","DOIUrl":"https://doi.org/10.1007/s11604-026-02084-5","url":null,"abstract":"<p><strong>Purpose: </strong>Accurate preoperative diagnosis of lymph node (LN) metastasis in esophageal squamous cell carcinoma (ESCC) is crucial for determining treatment strategies, including organ-sparing therapies. We aimed to develop and validate a deep learning (DL) model using rotational maximum-intensity projection (MIP) 18 F-FDG PET images to improve the prediction of LN metastasis.</p><p><strong>Materials and methods: </strong>This retrospective study included 185 patients with ESCC (146 receiving neoadjuvant chemotherapy) who underwent preoperative imaging using a silicon photomultiplier PET scanner. A convolutional neural network (CNN) was developed using six rotational MIP images (angles from - 60° to 90°). The architecture utilized a ResNet-50 backbone with weight sharing across views. The ground truth for LN metastasis was established via postoperative histopathology, including Grade 3 pathological response as positive. The performance of the model in the test set (n = 36) was compared with that of radiologist reports and SUVmax analysis using the area under the receiver operating characteristic curve (AUC) and diagnostic accuracy.</p><p><strong>Results: </strong>The CNN model achieved an AUC of 0.82 (95% CI 0.57-0.94), which was higher but not significantly different from the SUVmax method (0.77, p > 0.05). Although the differences were not statistically significant (p > 0.05), the CNN model achieved the highest absolute diagnostic accuracy of 86% at the optimal threshold, compared with the SUVmax-based method (67%), the clinical data model (75%), and radiologist reports (69%). Notably, while the CNN model exhibited a lower specificity (75%) than radiologist reports (92%), it demonstrated high sensitivity (92%) compared to radiologist (58%) and SUVmax (63%), effectively serving as a diagnostic safety net.</p><p><strong>Conclusion: </strong>Our PET-based CNN model using rotational MIP images demonstrated comparable diagnostic accuracy and higher sensitivity for LN metastasis in ESCC than the conventional methods. This proof-of-concept highlights its potential as a preoperative tool for optimizing treatment selection and minimizing understaging.</p>","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149001832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vendor-neutral-CT-like bone contrast MRI in ossification of posterior longitudinal ligament.","authors":"Akitoshi Inoue, Kanji Mori, Yoshiyuki Watanabe","doi":"10.1007/s11604-026-02078-3","DOIUrl":"https://doi.org/10.1007/s11604-026-02078-3","url":null,"abstract":"","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148989815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MAVERICK: connecting transformative topics with global expertise.","authors":"Yuko Nakamura, Shinji Naganawa","doi":"10.1007/s11604-026-02071-w","DOIUrl":"https://doi.org/10.1007/s11604-026-02071-w","url":null,"abstract":"","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148989658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comment on \"Role of extracellular volume fraction determined by dual-layer spectral detector CT in predicting the tumor grade of pancreatic neuroendocrine neoplasms\".","authors":"Deepti M Sati, Vanashri Dhananjay Shinde, Chhaya Agarwal","doi":"10.1007/s11604-026-02076-5","DOIUrl":"https://doi.org/10.1007/s11604-026-02076-5","url":null,"abstract":"","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148989602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}