Japanese Journal of Radiology最新文献

{"title":"MRI and proton MR spectroscopy in neonatal hypoxic-ischemic encephalopathy: a comprehensive imaging review.","authors":"Mikako Enokizono","doi":"10.1007/s11604-026-02083-6","DOIUrl":"https://doi.org/10.1007/s11604-026-02083-6","url":null,"abstract":"<p><p>Neonatal hypoxic-ischemic encephalopathy (HIE) remains a leading cause of neonatal mortality and long-term neurodevelopmental disability. Although cranial ultrasound is widely used as a bedside screening tool, brain MRI has become central to diagnosis, injury pattern classification, timing estimation, and outcome prediction. Furthermore, proton MR spectroscopy (¹H-MRS) provides complementary metabolic biomarkers that enhance prognostication. This review focuses on MRI and ¹H-MRS in neonatal encephalopathy due to hypoxic-ischemic injury, addressing both term and preterm infants. The pathophysiologic determinants of injury distribution are summarized, the optimal timing of imaging and diffusion evolution is discussed, and practical acquisition protocols including recommended sequences and ¹H-MRS parameters are proposed. Key MRI phenotypes in term infants-basal ganglia-thalamus injury, watershed/parasagittal cortical-subcortical injury, and global or near-total injury patterns are reviewed with attention to common pitfalls such as diffusion pseudonormalization and evolving T1/T2 signal changes. For preterm infants, this review highlights distinctive vulnerabilities of the germinal matrix and periventricular white matter, emphasizing the spectrum from punctate white matter injury (WMI) to cystic periventricular leukomalacia (PVL). For ¹H-MRS, voxel selection, echo time considerations, and interpretation of lactate, N-acetylaspartate (NAA), choline, creatine, and myo-inositol are detailed. Evidence suggests that deep gray matter lactate/NAA or NAA-based metrics serve as reliable and robust outcome biomarkers. Emerging directions including arterial spin labeling (ASL) perfusion are also discussed.</p>","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149206861","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":"Palliative radiotherapy for gastric cancer-related bleeding: a systematic review and meta-analysis of bleeding response and dose-response relationships.","authors":"Ruka Iguchi, Nobuki Imano, Tetsuo Saito, Shota Miyoshi, Takaaki Matsuura, Daisuke Kawahara, Ikuno Nishibuchi, May Abdel-Wahab, Yuji Murakami","doi":"10.1007/s11604-026-02094-3","DOIUrl":"https://doi.org/10.1007/s11604-026-02094-3","url":null,"abstract":"<p><strong>Purpose: </strong>Palliative radiotherapy is commonly used to control bleeding in advanced gastric cancer; however, the optimal dose-fractionation regimen as well as the dose-response relationship remain unclear. We aimed to evaluate the effectiveness of radiotherapy for gastric cancer-related bleeding and its association with dose fractionation.</p><p><strong>Materials and methods: </strong>We systematically searched PubMed, Scopus, Web of Science, Cochrane Library, and Ichushi-Web for studies published between January 2000 and August 2026 on palliative radiotherapy for gastric cancer-related bleeding. The primary endpoint was bleeding response rate. A random-effects meta-analysis was performed to estimate the pooled response rates. Meta-regression and subgroup analyses were conducted to explore dose-response relationships. Meta-regression was performed using study-level median biologically effective dose (BED) values.</p><p><strong>Results: </strong>A total of 31 studies were included. The pooled bleeding response rate was 75.9% (95% confidence interval, 69.7-81.2), with significant heterogeneity (I²= 67.5%). Egger's test suggested small study effects (P = 0.012). Meta-regression analysis demonstrated an association between a higher BED and an increased likelihood of response (P = 0.010). Subgroup analyses showed that higher BED categories were associated with higher response rates (P = 0.005). The pooled rebleeding rate was 32.4%. The median overall survival and rebleeding-free survival were 3.8 and 3.4 months, respectively. Radiotherapy was generally well tolerated, with a low incidence of grade ≥ 3 toxicities.</p><p><strong>Conclusions: </strong>Palliative radiotherapy is an effective and well-tolerated treatment for gastric cancer-related bleeding. Although study-level meta-regression identified a statistical association between higher BED and hemostatic response, this may largely reflect selection bias and methodological limitations rather than a true dose-response relationship. Given the poor prognosis of this population, shorter dose-fractionation regimens are appropriate for many patients, whereas higher-BED regimens remain reasonable for selected patients.</p>","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149206939","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":"MRI-defined parametrial venous invasion in locally advanced cervical cancer: association with pathological venous invasion, pretreatment lymph node metastasis, and survival outcomes.","authors":"Fumitaka Ejima, Ryoji Yamagishi, Arata Oose, Fumiko Kanzaki, Yuki Satake, Koji Takumi, Kiyohisa Kamimura, Hirokazu Otsuka, Shintaro Yanazume, Hiroaki Kobayashi, Ikumi Kitazono, Takashi Yoshiura","doi":"10.1007/s11604-026-02099-y","DOIUrl":"https://doi.org/10.1007/s11604-026-02099-y","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate MRI-defined parametrial venous invasion (mrPMVI) for detecting pathological parametrial venous invasion (pPMVI) and its associations with pretreatment lymph node metastasis (LNM) and survival outcomes in locally advanced cervical cancer.</p><p><strong>Materials and methods: </strong>This retrospective study included 42 patients with cervical cancer with parametrial invasion on MRI or histopathology, corresponding to International Federation of Gynecology and Obstetrics 2018 stage IIB or higher disease. Fifteen patients underwent surgery without preoperative therapy and were included in the pathological validation analysis. Image interpretation was primarily based on T2-weighted and diffusion-weighted imaging. Two radiologists independently assessed mrPMVI using a five-point scoring system. Scores ≥ 3 were predefined as mrPMVI-positive. Diagnostic performance for pPMVI and interobserver agreement were evaluated. Univariable logistic and Cox regression analyses were performed for pretreatment LNM and survival outcomes, respectively.</p><p><strong>Results: </strong>pPMVI was present in 10 of 15 patients. The five-point mrPMVI score showed an area under the receiver operating characteristic curve of 0.87 (95% confidence interval [CI], 0.60-0.98) for detecting pPMVI. The predefined threshold (≥ 3) yielded 30.0% sensitivity and 100% specificity. Interobserver agreement for the five-point mrPMVI score was substantial (linearly weighted κ = 0.75). mrPMVI positivity was associated with pretreatment LNM (odds ratio = 4.00, 95% CI: 1.05-15.26, p = 0.042). During a median follow-up of 24.0 months, 16 patients experienced disease progression and 10 died. mrPMVI positivity was associated with shorter progression-free survival (hazard ratio = 34.25, 95% CI: 4.35-269.91; p < 0.001) and overall survival (hazard ratio = 10.16; 95% CI: 1.28-80.61, p = 0.028).</p><p><strong>Conclusion: </strong>The mrPMVI score showed potential for identifying pPMVI, although the predefined threshold was highly specific but insensitive. mrPMVI positivity was associated with pretreatment LNM and survival outcomes, suggesting potential complementary value for risk characterization in locally advanced cervical cancer.</p>","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149207001","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":"In reply to the comment on \"Role of extracellular volume fraction determined by dual-layer spectral detector CT in predicting the tumor grade of pancreatic neuroendocrine neoplasms\".","authors":"Nobuhiro Fujita","doi":"10.1007/s11604-026-02093-4","DOIUrl":"https://doi.org/10.1007/s11604-026-02093-4","url":null,"abstract":"","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149206870","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":"In reply.","authors":"Pei-Fan Shih","doi":"10.1007/s11604-026-02098-z","DOIUrl":"https://doi.org/10.1007/s11604-026-02098-z","url":null,"abstract":"","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149206905","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":"Comparison of PMAneo and RAPID in acute ischemic stroke: agreement in CT perfusion analysis and DEFUSE 3 imaging eligibility.","authors":"Yohei Ikebe, Keiji Noutomi, Kazuma Ishibashi, Mari Anzai, Manabu Shirakawa, Toshiyuki Onda, Manabu Inoue, Bunya Takahashi, Ryosuke Shimura, Yuki Takano, Motoma Kanaya, Koki Iura, Hiroyuki Kameda, Taisuke Harada, Yukie Shimizu, Noriyuki Fujima, Shinichi Yoshimura, Kohsuke Kudo","doi":"10.1007/s11604-026-02095-2","DOIUrl":"https://doi.org/10.1007/s11604-026-02095-2","url":null,"abstract":"<p><strong>Purpose: </strong>Automated computed tomography perfusion (CTP) analysis plays a key role in triaging acute ischemic stroke (AIS). This study aimed to evaluate the agreement of PMAneo compared with RAPID in a multicenter setting.</p><p><strong>Materials and methods: </strong>We retrospectively reviewed 99 patients with anterior circulation AIS from three stroke centers using four different CT scanners. CTP data were processed using both PMAneo and RAPID. Volumetric agreement for ischemic core volume and Tmax > 6 s volume was assessed using intraclass correlation coefficients (ICCs) and Bland-Altman analysis. Multivariable regression analysis was performed to identify factors associated with volume discrepancies. EVT imaging eligibility was evaluated according to the DEFUSE 3 criteria (ischemic core volume < 70 mL, mismatch ratio ≥ 1.8, and absolute mismatch volume ≥ 15 mL), using RAPID as the comparator.</p><p><strong>Results: </strong>Ischemic core volumes showed excellent agreement between the two platforms (ICC = 0.881, 95% CI 0.827-0.918), and Tmax > 6 s volumes showed good agreement (ICC = 0.761, 95% CI 0.283-0.896), whereas mismatch volumes showed moderate agreement (ICC = 0.661, 95% CI 0.146-0.844). For the ischemic core threshold (< 70 mL), PMAneo demonstrated 100% (95% CI 96-100%) relative sensitivity and 67% (95% CI 38-88%) relative specificity. For the full DEFUSE 3 criteria, the relative sensitivity and specificity were 81% (95% CI 70-89%) and 84% (95% CI 66-95%), respectively. Bland-Altman analysis demonstrated proportional bias, with PMAneo underestimating volumes relative to RAPID as lesion size increased. Basal ganglia involvement and imaging site were significantly associated with these volume differences (p < 0.05).</p><p><strong>Conclusion: </strong>PMAneo showed high volumetric agreement and comparable DEFUSE 3 imaging eligibility to RAPID, suggesting it is a reliable alternative for automated CTP analysis. Although proportional bias and potential diagnostic discrepancies were observed in borderline cases near clinically relevant thresholds, PMAneo may facilitate broader access to automated CTP analysis.</p>","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149216157","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":"Radiologic-pathologic correlation of tonsillar lymphoid papillary hyperplasia.","authors":"Naoto Ozawa, Hiroki Kato, Masayuki Matsuo","doi":"10.1007/s11604-026-02091-6","DOIUrl":"https://doi.org/10.1007/s11604-026-02091-6","url":null,"abstract":"","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149181862","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":"Modality mismatch or clinical blind spot? Methodological considerations in benchmarking large language models against human raters of PET/CT radiation-safety videos.","authors":"Hao He, Yuting Liu, Jiadong Yu","doi":"10.1007/s11604-026-02092-5","DOIUrl":"https://doi.org/10.1007/s11604-026-02092-5","url":null,"abstract":"","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149181893","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":"Atypical ovarian fibroma and thecoma mimicking malignancy: clue for differentiation from malignant solid tumors.","authors":"Takanori Aonuma, Ayumi Ohya, Daiya Takekoshi, Kazuki Oyama, Yasunari Fujinaga","doi":"10.1007/s11604-026-02088-1","DOIUrl":"https://doi.org/10.1007/s11604-026-02088-1","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate the characteristic findings of ovarian fibroma and thecoma (FT) with atypical magnetic resonance imaging (MRI) findings that mimic malignancy and to validate the improvement in diagnostic performance in differentiating between FTs and malignant solid tumors.</p><p><strong>Materials and methods: </strong>This retrospective study included 114 patients (119 lesions: 34 FT and 85 malignant tumors) with pathologically confirmed solid ovarian tumors who underwent preoperative MRI. Signal intensity on T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) maps, and time-intensity curves from dynamic contrast-enhanced MRI (DCE-MRI) were evaluated. FT lesions showing low signal intensity on both T2WI and DWI were defined as classic, whereas others were considered atypical. The diagnostic performance of combined imaging findings was also assessed. A reader study was also performed by three radiologists.</p><p><strong>Results: </strong>Among the FT lesions, 55.9% demonstrated intermediate signal intensity on T2WI, and 32.4% showed diffusion restriction. Atypical FT accounted for 56% of all FT cases. The combination of T2WI and DWI showed high specificity (98.8%) but low sensitivity (44.1%) for diagnosing FT as benign. In contrast, for the diagnosis of benign lesions, the combination of T2WI and DCE-MRI demonstrated superior diagnostic performance, with a sensitivity, specificity, positive predictive value, and negative predictive value of 84.0%, 95.9%, 87.5%, and 94.6%, respectively. Reader performance improved when the combined interpretation of T2WI and DCE-MRI findings was emphasized. Using this approach, the estimated misdiagnosis rate of FT as malignant decreased from approximately 40% to 16%.</p><p><strong>Conclusion: </strong>Atypical FT frequently mimics malignant ovarian tumors on MRI. The combination of T2WI and DCE-MRI findings provides the best diagnostic performance and significantly reduces misdiagnosis. However, a subset of FT remains indistinguishable from malignancy, highlighting the need for careful interpretation.</p>","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149109756","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":"The seventh asian radiology summit: governance of asian radiological societies: shared challenges and future directions.","authors":"Yoko Satoh, Minako Azuma, Kei Yamada, Noriyuki Tomiyama","doi":"10.1007/s11604-026-02086-3","DOIUrl":"https://doi.org/10.1007/s11604-026-02086-3","url":null,"abstract":"","PeriodicalId":14691,"journal":{"name":"Japanese Journal of Radiology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149109733","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}