Fujita Medical Journal最新文献

{"title":"<i>Fusobacterium nucleatum</i> as a two-hit amplifier in colorectal cancer pathogenesis: intersection of local and systemic mechanisms via the gut-kidney axis.","authors":"Hidehisa Shimizu","doi":"10.20407/fmj.2025-042","DOIUrl":"10.20407/fmj.2025-042","url":null,"abstract":"<p><p>Colorectal cancer (CRC) is a complex malignancy driven by genetic, environmental, and lifestyle factors. A critical contributor to CRC tumor initiation and progression is gut microbial dysbiosis. <i>Fusobacterium nucleatum</i>, an oral commensal bacterium, is a potent promoter of malignancy rather than a passive colonizer. This review examines the molecular mechanisms by which <i>F. nucleatum</i> promotes CRC progression, focusing on one indirect systemic and three direct local mechanisms. First, the lipopolysaccharide-Toll-like receptor 4 axis sustains a chronic inflammatory loop that remodels the tumor microenvironment. Second, the fibroblast activation protein 2-T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain interaction facilitates immune evasion by suppressing T cell and natural killer cell cytotoxic activity. Third, the <i>Fusobacterium</i> adhesin A-E-cadherin/Wnt pathway acts as a potent \"second hit,\" amplifying β-catenin signaling and driving proliferation in cells with pre-existing mutations in adenomatous polyposis coli. Beyond these local effects, this review highlights a novel indirect mechanism involving the gut-kidney axis. Specifically, <i>F. nucleatum</i> is hypothesized to contribute to systemic levels of indoxyl sulfate, a uremic toxin that reinforces a systemic feedback loop via pro-proliferative signaling. These synergistic mechanisms collectively remodel the tumor microenvironment by promoting immune suppression, chronic inflammation, and metabolic reprogramming. Within this framework, <i>F. nucleatum</i> collaborates with genetic lesions to accelerate disease progression. This framework provides a crucial foundation for developing innovative diagnostics and microbe-targeted therapies-such as phage therapy and vaccines-to substantially improve the prognosis of patients with CRC.</p>","PeriodicalId":33657,"journal":{"name":"Fujita Medical Journal","volume":"12 2","pages":"89-97"},"PeriodicalIF":0.0,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13129706/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147821610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Association between blood mitochondrial DNA copy number and cognitive function: A cross-sectional study based on the Yakumo Study.","authors":"Atsushi Teshigawara, Genki Mizuno, Hiroya Yamada, Yoshiki Tsuboi, Eiji Munetsuna, Yuji Hattori, Mirai Yamazaki, Yoshitaka Ando, Itsuki Kageyama, Takuya Wakasugi, Hayato Ichikawa, Hiroshi Okumiyama, Ryosuke Fujii, Akihiko Iwahara, Takeshi Hatta, Hiroaki Ishikawa, Koji Ohashi, Koji Suzuki","doi":"10.20407/fmj.2025-038","DOIUrl":"10.20407/fmj.2025-038","url":null,"abstract":"<p><strong>Objectives: </strong>Mitochondrial dysfunction has been implicated in neurodegenerative diseases, but evidence regarding its association with cognitive performance in the general population remains limited. This study aimed to examine the association between peripheral blood mitochondrial DNA copy number (mtDNA-CN) and cognitive function in the general Japanese population.</p><p><strong>Methods: </strong>We conducted a cross-sectional analysis of 282 participants (134 men and 148 women) from the Yakumo Study, a population-based health examination in Hokkaido, Japan. Peripheral blood mtDNA-CN was measured by quantitative real-time PCR and categorized into tertiles. Cognitive function was assessed using the short version of the Mini-Mental State Examination (SMMSE), the Logical Memory Test (LMT), and the Digit Cancellation Test (D-CAT). Logistic regression analyses were performed to evaluate the association between mtDNA-CN levels and cognitive performance, with adjustments for relevant demographic and clinical factors.</p><p><strong>Results: </strong>Lower mtDNA-CN was significantly associated with poorer SMMSE scores in women and with reduced D-CAT3 performance-reflecting attention and executive function-in men. No significant associations were observed for LMT scores in either sex. These domain- and sex-specific associations remained consistent after adjustment for potential confounders.</p><p><strong>Conclusions: </strong>Lower mtDNA-CN was associated with poorer cognitive performance in the general Japanese population, in a cognitive domain- and sex-specific manner. mtDNA-CN thus has potential as a non-invasive biomarker for the early identification of individuals at increased risk of cognitive decline. Longitudinal studies are necessary to evaluate its predictive utility and potential application in dementia prevention strategies.</p>","PeriodicalId":33657,"journal":{"name":"Fujita Medical Journal","volume":"12 2","pages":"151-158"},"PeriodicalIF":0.0,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13129713/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147821634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feasibility of using a pocket-sized ultrasound imaging device for detecting insulin-derived amyloidosis-like findings in patients with diabetes mellitus: a preliminary study.","authors":"Naoko Kageura, Hiroji Takai, Yasuo Takatsu, Atsushi Suzuki, Shigeki Kobayashi, Kazuki Takano, Ayano Nakai, Junko Sugama, Kimie Takehara","doi":"10.20407/fmj.2025-028","DOIUrl":"10.20407/fmj.2025-028","url":null,"abstract":"<p><strong>Objectives: </strong>Insulin-derived amyloidosis (IDA) reduces insulin absorption, increasing the risk of poor glycemic control; however, early detection remains challenging. Although ultrasound can identify IDA, the effectiveness of portable pocket-sized devices has not been evaluated. This study was performed to evaluate the detectability of findings suggestive of IDA using a pocket-sized ultrasound device on the abdominal region, the most common site for stable insulin absorption in patients with diabetes mellitus.</p><p><strong>Methods: </strong>This cross-sectional observational study was conducted in the diabetes ward of a university hospital between July and December 2024. The participants were inpatients with diabetes who had been receiving insulin injections for more than 1 month. Findings suggestive of IDA were assessed through visual inspection and palpation, magnetic resonance imaging (MRI), high-performance ultrasonography, and a pocket-sized ultrasound device. The concordance rate between the pocket-sized ultrasound device and other assessment methods was calculated.</p><p><strong>Results: </strong>Of the 20 participants enrolled, 5 met the exclusion criteria; thus, data from 15 participants were included in the final analysis. Findings suggestive of IDA were identified in nine patients (60.0%) by visual inspection and palpation and in eight patients (53.3%) by the pocket-sized ultrasound device, high-performance ultrasound, and MRI. The concordance rate among the pocket-sized ultrasound device, high-performance ultrasound, and MRI was 100%, while the concordance rate between visual inspection with palpation and the pocket-sized ultrasound device was 80%.</p><p><strong>Conclusions: </strong>These findings suggest that a pocket-sized ultrasound device has the potential to detect findings suggestive of IDA and may be suitable for use in clinical practice.</p>","PeriodicalId":33657,"journal":{"name":"Fujita Medical Journal","volume":"12 2","pages":"143-150"},"PeriodicalIF":0.0,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13129715/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147821700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationships between pre-licensure academic performance and self-assessed clinical competence after graduation in recently graduated physical therapists.","authors":"Tatsuya Kondo, Hiroaki Sakurai, Kei Ohtsuka, Nobushiro Okuchi, Yuta Ogawa, Hisanobu Hayashi, Yukari Suzuki, Yoshikiyo Kanada","doi":"10.20407/fmj.2025-029","DOIUrl":"10.20407/fmj.2025-029","url":null,"abstract":"<p><strong>Objectives: </strong>This study examined the relationship between pre-licensure academic performance and self-assessed clinical competence, as measured by the Clinical Competence Evaluation Scale in Physical Therapy (CEPT), among novice physical therapists with up to 1 year of clinical experience after graduation.</p><p><strong>Methods: </strong>The study participants were 37 graduates of a vocational school who had passed the national physical therapy licensure examination and were employed in healthcare or welfare facilities. Pre-graduation performance data included first-year and second-year academic grades, scores in basic and professional foundational subjects, and Clinical Training III evaluations. Self-assessments after graduation were conducted using the CEPT, which contains 53 items across seven competency categories. Correlational analyses were performed to investigate associations between pre-graduation academic metrics and CEPT scores.</p><p><strong>Results: </strong>There were significant negative correlations between first-year and second-year academic performance, scores in basic professional subjects, advanced professional subjects and the combined scores of basic and advanced professional subjects with CEPT domains related to \"Knowledge\" and \"Decision-making skills.\" Scores in basic professional subjects were the lowest among all categories and exhibited the strongest negative correlation with self-assessment.</p><p><strong>Conclusions: </strong>Students with higher levels of academic performance tended to rate themselves lower in early self-assessment after graduation, suggesting a possible lack of confidence in their knowledge or difficulties adapting to the complexities of clinical training. These findings highlight the potential value of integrating metacognitive support and self-assessment training into the physical therapy curriculum to foster practical competence and professional growth.</p>","PeriodicalId":33657,"journal":{"name":"Fujita Medical Journal","volume":"12 2","pages":"179-187"},"PeriodicalIF":0.0,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13129714/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147821796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pathophysiological significance of cholesterol in ciliopathies.","authors":"Takeshi Itabashi, Tomoka Morita, Moe Hirosawa, Daigo Kobayashi, Alamgir Hasan, Sotai Kimura, Hiroshi Itoh, Tatsuo Miyamoto","doi":"10.20407/fmj.2025-044","DOIUrl":"10.20407/fmj.2025-044","url":null,"abstract":"<p><p>Primary cilia are sensory organelles essential for cellular signaling, the dysfunction of which causes ciliopathies, characterized by polycystic kidney disease, retinopathy, and developmental anomalies. Here, we review recent studies which have shown that cholesterol is a critical mediator of ciliary function and the pathogenesis of ciliopathies. Ciliary membranes show distinct cholesterol enrichment that is essential for the physiological function of various G-protein-coupled receptors and ion channels. Defects in <i>de novo</i> cholesterol synthesis (Smith-Lemli-Opitz syndrome) and peroxisome-facilitated cholesterol trafficking to ciliary membranes (Zellweger syndrome) result in ciliopathy-like phenotypes, establishing ciliary cholesterol insufficiency as a novel pathological mechanism. The polycystin complex associated autosomal dominant polycystic kidney disease localizes into ciliary membranes in a cholesterol-dependent manner. Specific cholesterol-binding sites in polycystin-2 are crucial for the distribution of cholesterol to cilia, while pathogenic mutations at these sites disrupt these interactions. We also discuss the previously underappreciated connections between ciliopathies, cholesterol, and other disorders such as cancer and neurodegenerative diseases, and opportunities for manipulating cholesterol for novel therapeutic strategies.</p>","PeriodicalId":33657,"journal":{"name":"Fujita Medical Journal","volume":"12 2","pages":"98-105"},"PeriodicalIF":0.0,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13129716/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147821769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a model to predict gait independence in individuals with very severe gait disorder due to subacute hemiparetic stroke.","authors":"Ryo Makino, Satoshi Hirano, Daisuke Imoto, Hiroki Kawanai, Makoto Watanabe, Takuma Ishihara, Shigeru Sonoda, Yohei Otaka","doi":"10.20407/fmj.2025-026","DOIUrl":"10.20407/fmj.2025-026","url":null,"abstract":"<p><strong>Objectives: </strong>We aimed to develop and validate a model to predict gait independence at discharge from inpatient rehabilitation in individuals with subacute hemiparetic stroke who have very severe gait disorder.</p><p><strong>Methods: </strong>Overall, 298 individuals with subacute hemiparetic stroke and completely dependent gait were selected in one hospital as the training cohort. Seventy-seven individuals were selected in another hospital as the validation cohort. The prediction model was developed using multivariable logistic regression analysis, with individual characteristics selected based on a p-value threshold (<0.10) in the training cohort. Sensitivity, specificity, and area under the curve of the receiver operating characteristic curve were calculated in the training cohort, and external validation was conducted using the validation cohort.</p><p><strong>Results: </strong>In total, 102 (34.2%) and 40 (52.0%) individuals in the training and validation cohorts achieved independent gait while hospitalized, respectively. The prediction model factors were age, days from onset to admission, stroke type, affected side, severity of paresis, unaffected side function, and cognitive function. The sensitivity, specificity, and area under the curve in the training cohort were 0.81, 0.80, and 0.88, respectively. Corresponding values in the validation cohort were 0.82, 0.70, and 0.83, respectively.</p><p><strong>Conclusions: </strong>A model combining age, days from onset to admission, stroke type, affected side, severity of paresis, unaffected side muscle strength, and cognitive function effectively predicted gait independence at discharge in individuals with very severe gait disorder due to subacute hemiparetic stroke.</p>","PeriodicalId":33657,"journal":{"name":"Fujita Medical Journal","volume":"12 1","pages":"60-66"},"PeriodicalIF":0.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12865285/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146120150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Usefulness of embryo evaluation via artificial intelligence-based image analysis.","authors":"Takuma Kishida, Haruki Nishizawa","doi":"10.20407/fmj.2025-016","DOIUrl":"10.20407/fmj.2025-016","url":null,"abstract":"<p><strong>Objective: </strong>Life Whisperer Viability (LW) is a software that evaluates embryos from a single image of blastocyst using artificial intelligence and is expected to improve the objectivity of embryo evaluation. In the present study, we retrospectively analyzed the clinical utility of LW.</p><p><strong>Methods: </strong>This study included 198 cycles in 135 patients who underwent frozen single embryo transfer. LW scores of transferred embryos were obtained from images taken approximately 116 h after fertilization. Based on LW scores, patients were divided into four groups (poor: 0-2.4; fair: 2.5-7.4; good: 7.5-8.9; excellent: 9.0-10), and rates of positive fetal heartbeat were compared among the groups. In addition, logistic regression analysis was performed to evaluate the association between LW score and the presence or absence of fetal heartbeat.</p><p><strong>Results: </strong>The rate of positive fetal heartbeat was significantly higher in the excellent group (64.3%, 36/56) than in the poor group (27.6%, 8/29) (<i>P</i><0.05). Logistic regression analysis showed that the odds ratio for LW score was 1.150 (95% confidence interval: 1.040-1.280; <i>P</i><0.05), indicating a significant association between LW score and presence or absence of fetal heartbeat.</p><p><strong>Conclusion: </strong>LW enables selection of embryos with a high potential for clinical pregnancy, demonstrating its clinical utility.</p>","PeriodicalId":33657,"journal":{"name":"Fujita Medical Journal","volume":"12 1","pages":"29-32"},"PeriodicalIF":0.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12865280/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146120276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feasibility of bioabsorbable polyglycolic acid sheet and fibrin glue therapy for ulcer sealing after gastric endoscopic submucosal dissection.","authors":"Tomoyuki Shibata, Takamitsu Ishizuka, Keishi Koyama, Hyuga Yamada, Noriyuki Horiguchi, Kohei Funasaka, Ryoji Miyahara, Tomomitsu Tahara, Yoshiki Hirooka","doi":"10.20407/fmj.2025-006","DOIUrl":"10.20407/fmj.2025-006","url":null,"abstract":"<p><strong>Objectives: </strong>Combined therapy using a bioabsorbable polyglycolic acid sheet (BAPGAS) and fibrin glue (FG) has been employed to prevent postoperative perforation. More recently, this therapy has been applied to ulcers that develop after endoscopic submucosal dissection (ESD) for early digestive tract tumors. This study was performed to evaluate the sealing effect of this combined therapy on ulcers that develop after ESD for early gastric tumors.</p><p><strong>Methods: </strong>This study included nine patients with early gastric cancer or adenoma who were treated with ESD. Ulcers that developed after ESD were covered with BAPGAS and sealed with FG spray. To assess ulcer bleeding and healing status, endoscopy was performed on postoperative days 1, 7, 28, and 56.</p><p><strong>Results: </strong>On days 1 and 7, clots were observed in only two patients, and no bleeding occurred in any patient. As a result, endoscopic hemostasis was not required. In one patient, scar healing was achieved by day 28. By day 56, seven of the nine patients' ulcers had reached the scar stage, and no bleeding was observed in any patient. Changes in hemoglobin levels 1 week after ESD were not significant (from 13.1 to 12.7 g/dL). The average BAPGAS covering time was approximately 40 minutes. No correlation was found between BAPGAS covering time and ESD procedure time, dissection time, or resected area.</p><p><strong>Conclusions: </strong>Combined therapy with BAPGAS and FG is a promising new treatment for preventing bleeding from artificial ulcers following ESD and may help avoid the need for additional endoscopic hemostasis.</p>","PeriodicalId":33657,"journal":{"name":"Fujita Medical Journal","volume":"12 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12862357/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146114396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SMARCA4 regulates SMARCAD1 expression for toleration of replication stress in non-small cell lung cancer.","authors":"Patinya Sawangsri, Siripan Limsirichaikul, Toshiyuki Takeuchi, Yasuyoshi Mizutani, Dat Quoc Tran, Taisuke Kajino, Motoshi Suzuki, Atsuko Niimi","doi":"10.20407/fmj.2025-017","DOIUrl":"10.20407/fmj.2025-017","url":null,"abstract":"<p><strong>Objectives: </strong>SMARCA4, a core component of the SWI/SNF chromatin remodeling complex, is frequently mutated in non-small cell lung cancer (NSCLC). SMARCA4-deficient cancer cells are associated with increased replication stress, one of the major causes of genomic instability, which may lead to cancer. SMARCAD1, a chromatin remodeler, is known as replication fork progressor, and SMARCAD1 dysregulation is also closely related to cancer development. This study aimed to investigate the role of the SMARCA4-SMARCAD1 axis in the toleration of replication stress in NSCLC, focusing on the regulatory relationship between SMARCA4 and SMARCAD1 during replication stress conditions.</p><p><strong>Methods: </strong>Human NSCLC cell lines (Calu-6, NCI-H1975, Calu-1, and NCI-H460) were used for experiments. SMARCA4 and SMARCAD1 expression levels were analyzed by quantitative RT-PCR and immunoblotting. Transcriptional regulation of SMARCAD1 was analyzed by chromatin immunoprecipitation assay. Immunofluorescent analysis was performed to assess SMARCAD1 accumulation at stalled replication forks. Clonogenic assays were conducted to evaluate the roles of SMARCA4 and SMARCAD1 in cell survival.</p><p><strong>Results: </strong>SMARCAD1 was highly expressed in SMARCA4-depleted cells under replication stress. Immunofluorescent analysis revealed significant accumulation of SMARCAD1 at stalled replication forks in SMARCA4-depleted cells. Chromatin immunoprecipitation assays demonstrated that SMARCA4 bound to the transcriptional regulatory region of <i>SMARCAD1</i>, and that this efficacy was decreased under replication stress, suggesting that SMARCA4 is a transcriptional suppressor of <i>SMARCAD1</i>. In a clonogenic analysis either SMARCA4 or SMARCAD1 is required for cell survival.</p><p><strong>Conclusions: </strong>The SMARCA4-SMARCAD1 axis is a novel mechanism that provides tolerance for replication stress.</p>","PeriodicalId":33657,"journal":{"name":"Fujita Medical Journal","volume":"12 1","pages":"40-49"},"PeriodicalIF":0.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12865287/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146120342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the orientation dependence of optically stimulated luminescence dosimeters in computed tomography dosimetry using an anthropomorphic phantom under clinical imaging conditions.","authors":"Takuma Ichikawa, Yusei Nishihara, Tomonobu Haba, Yasuki Asada","doi":"10.20407/fmj.2025-014","DOIUrl":"10.20407/fmj.2025-014","url":null,"abstract":"<p><strong>Objective: </strong>Small dosimeters such as optically stimulated luminescence dosimeters (OSLDs) and thermoluminescence dosimeters (TLDs) are used in anthropomorphic phantoms to measure actual organ exposure in X-ray computed tomography (CT) examinations. Nagase-Landauer currently supplies nanoDot dosimeters that employ OSLDs. The flat structure of nanoDot dosimeters causes their sensitivity to fluctuate according to the direction of the incident X-rays. We evaluated the effect of OSLD angle on measured values when dosimeters were placed within an anthropomorphic phantom and dosimetry was performed to mimic X-ray CT examinations.</p><p><strong>Methods: </strong>The dependence of OSLD placement angle on measured values was evaluated at eight points in the thorax and abdomen of the anthropomorphic phantom including the lung field, near the center of the phantom, near the body surface, and near the tissue boundary.</p><p><strong>Results: </strong>The system error for OSLDs positioned at different angles in the anthropomorphic phantom was 6.58%. Variation of measured values with the OSLD placement angles in the phantom resulted in errors ranging from -7.3% to +5.4%.</p><p><strong>Conclusion: </strong>Placement angle had little effect on measurement values when system error was considered. Therefore, it is not necessary to consider placement angle when measuring organ doses using OSLDs.</p>","PeriodicalId":33657,"journal":{"name":"Fujita Medical Journal","volume":"12 1","pages":"67-72"},"PeriodicalIF":0.0,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12862347/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146114365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}