A novel method for determining dose distribution on panoramic reconstruction computed tomography images from radiotherapy computed tomography.

Purpose: Patients with head and neck cancer (HNC) who undergo dental procedures during radiotherapy (RT) face an increased risk of developing osteoradionecrosis (ORN). Accordingly, new tools must be developed to extract critical information regarding the dose delivered to the teeth and mandible. This article proposes a novel approach for visualizing 3-dimensional planned dose distributions on panoramic reconstruction computed tomography (pCT) images. Materials and Methods: Four patients with HNC who underwent volumetric modulated arc therapy were included. One patient experienced ORN and required the extraction of teeth after RT. In the study approach, the dental arch curve (DAC) was defined using an open-source platform. Subsequently, pCT images and dose distributions were generated based on the new coordinate system. All teeth and mandibles were delineated on both the original CT and pCT images. To evaluate the consistency of dose metrics, the Mann-Whitney U test and Student t-test were employed. Results: A total of 61 teeth and 4 mandibles were evaluated. The correlation coefficient between the 2 methods was 0.999, and no statistically significant difference was observed (P>0.05). This method facilitated a straightforward and intuitive understanding of the delivered dose. In 1 patient, ORN corresponded to the region of the root and the gum receiving a high dosage (approximately 70 Gy). Conclusion: The proposed method particularly benefits dentists involved in the management of patients with HNC. It enables the visualization of a 3-dimensional dose distribution in the teeth and mandible on pCT, enhancing the understanding of the dose delivered during RT.

Dosimetric impact of the respiratory motion of the liver dome in stereotactic body radiotherapy for spine metastasis: A planning study.

PURPOSE: This study aimed to clarify the dosimetric impact of the respiratory motion of the liver on stereotactic body radiation therapy (SBRT) for spine metastasis and examine the utility of introducing beam avoidance (beam-off at specific gantry angles). METHODS: A total of 112 consecutive patients who underwent SBRT for spine metastasis between 2018 and 2024 were examined. Overall, 15 patients who had lesions near the liver dome were included in this study. Retrospective treatment plans were generated using computed tomography (CT) images acquired during inhalation and exhalation to evaluate the dosimetric impact of respiratory motion of the liver. The dose difference (DD) and relative value (DD%) were evaluated using the dose-volume histogram (DVH) metrics, planning target volume Dmax, D95%, spinal cord D0.035 cc, and esophagus D2.5 cc. The magnitude of the liver movements was evaluated based on differences of liver size Lave at the isocentric axial plane between the inspiratory and expiratory CT images. RESULTS: The DD in almost all DVH metrics tended to increase when the liver moved away from the target during inhalation: For example, Mean ± $ \pm $ a standard deviation (SD) DD in PTV D95% for the treatment plan incorporating beam avoidance and those without beam avoidance was 0.5 ± $\pm$ 0.3 and 0.9 ± $ \pm $ 0.6 Gy, respectively. The spinal cord D0.035 cc for those shows 0.4 ± $ \pm $ 0.2 and 0.7 ± $ \pm $ 0.7 Gy, respectively. The treatment plans without beam avoidance also showed moderate or strong correlations between Lave and DD for almost all DVH metrics. No correlation was seen in the beam avoidance plan. The spinal cord D0.035 cc revealed approximately 1 Gy or +4% in DD when Lave was < -4 cm. CONCLUSIONS: Respiratory motion of the liver dome can cause substantial dosimetric discrepancies in the dose delivered to the spinal cord, although the extent depends on patient variables. Dose assessment should be performed for determining the appropriate means of respiratory management, such as breath-hold. Alternatively, beam avoidance effectively mitigates the impact.

Propriety of various examinations for subjective symptoms of olfactory disorders.

PURPOSE: In Japan, two types of tests for diagnosing olfactory disorders, T and T (T&T) olfactometry and intravenous olfactory tests, are covered by insurance and performed on patients with olfactory disorders. This study examined the validity of these olfactory tests and whether psychophysical or morphological tests are more helpful in evaluating olfactory disorders. METHODS: We evaluated patients who visited our department and underwent two types of olfaction tests and sinus computed tomography (CT). Data regarding the age, sex, peripheral blood eosinophil percentage, presence of bronchial asthma, diagnoses, olfactory symptom score, results of the two olfactory tests, and CT findings in eligible patients were extracted from medical records and retrospectively reviewed. RESULTS: One hundred and sixty-three patients underwent all tests during the study period. The results of the T&T olfactometry and intravenous olfactory tests were significantly correlated. However, only the results of T&T olfactometry and olfactory cleft opacification on CT were statistically significant predictors of the olfactory symptom scores. CONCLUSION: T&T olfactometry and CT evaluations of olfactory cleft opacification helped evaluate olfactory dysfunction. It is important to note that intravenous olfactory tests are best performed with careful control and not blindly to assess olfactory disorders.

Primary intraosseous cavernous hemangioma of the clivus: A case report and literature review.

Background: The radiographic presentation of the primary intraosseous cavernous hemangiomas (PICHs) is nonspecific. We report a case of clival PICH mimicking a chordoma with a literature review. Case Description: A 57-year-old woman presented with diplopia that started a few days before the presentation. She had transient diplopia at the right lateral gaze and upper gaze with normal eye movement. The symptoms disappeared spontaneously 1 week later. She had no other complaints or neurological deficits. Computed tomography revealed an intraosseous mass lesion and bone erosion of the middle and lower clivus, extending laterally to the right occipital condyle. Magnetic resonance imaging (MRI) showed hyperintense and hypointense components on T2- and T1-weighted images, respectively. The lesion was larger than on MRI performed 10 years earlier. Chordoma or chondroma was considered a possible preoperative diagnosis. An endoscopic transsphenoidal approach removed the tumor. In the operating view, the lesion appeared as "moth-eaten" bony interstices filled with vascular soft tissue. Histologically, an intraosseous cavernous hemangioma was diagnosed. Conclusion: Diagnosis before surgery is difficult without characteristic radiographic findings. When making a differential diagnosis of malignant skull lesions, PICH should be considered.

Neurolymphomatosis diagnosed after a recurrence of facial palsy.

Neurolymphomatosis (NL) is a rare complication of non-Hodgkin's lymphoma, characterized by the infiltration of lymphoma cells into the peripheral nerves. A 54-year-old woman initially presented with right facial palsy without any other significant symptoms and was diagnosed with Bell's palsy. Despite initial improvement, her condition recurred, prompting further evaluation. Magnetic resonance imaging (MRI) revealed contrast enhancement from the tympanic segment to the surface of the masseter muscle along the right facial nerve and an adjacent mass lesion. Biopsy of the mass revealed a diagnosis of T-cell/histiocyte-rich large B-cell lymphoma. Chemotherapy resulted in complete resolution of facial palsy. Follow-up MRI confirmed the absence of contrast enhancement along the facial nerve. Facial palsy was considered to be caused by NL. This case was classified as that of primary NL because the facial palsy was the first manifestation of a hematologic malignancy. Recurrent facial palsy, which is atypical in Bell's palsy, led to further evaluation with MRI, which finally resulted in the diagnosis of malignant lymphoma. In cases of recurrent facial palsy, clinicians should consider various diagnoses, including that of NL, and advocate early imaging tests and biopsy, if possible, for accurate diagnosis and improved outcomes.

A method for delivering the required neutron fluence in an accelerator-based boron neutron capture therapy system employing a lithium target.

Accelerator-based boron neutron capture therapy (BNCT) systems employing a solid-state lithium target indicated the reduction of neutron flux over the lifetime of a target, and its reduction could represent the neutron flux model. This study proposes a novel compensatory approach for delivering the required neutron fluence and validates its clinical applicability. The proposed approach relies on the neutron flux model and the cumulative sum of real-time measurements of proton charges. The accuracy of delivering the required neutron fluence for BNCT using the proposed approach was examined in five Li targets. With the proposed approach, the required neutron fluence could be delivered within 3.0%, and within 1.0% in most cases. However, those without using the proposed approach exceeded 3.0% in some cases. The proposed approach can consider the neutron flux reduction adequately and decrease the effect of uncertainty in neutron measurements. Therefore, the proposed approach can improve the accuracy of delivering the required fluence for BNCT even if a neutron flux reduction is expected during treatment and over the lifetime of the Li target. Additionally, by adequately revising the approach, it may apply to other type of BNCT systems employing a Li target, furthering research in this direction.

Predicting macroinvertebrate average score per taxon (ASPT) at water quality monitoring sites in Japanese rivers.

Biomonitoring with bioindicators such as river macroinvertebrates is fundamental for assessing the status of freshwater ecosystems. In Japan, water quality and biomonitoring surveys are conducted separately, leading to a lack of nationwide information on their relationships and the biological status of water quality monitoring (WQM) sites. To understand the biological status of WQM sites across Japan, we developed a multiple linear regression model to estimate the average score per taxon (ASPT) using river macroinvertebrate data surveyed at a total of 237 "aligned" sites based on the co-occurrence of biomonitoring and WQM sites. The resulting regression model with eight predictors, such as biological oxygen demand, the proportion of urban areas in the catchment, could predict ASPT with reasonable accuracy (e.g., an error of ±1 for 96% of the aligned data). Using this model, we estimated ASPT values at 2925 WQM sites in rivers nationwide, categorizing them into four levels of river environment quality: "very good" (29% of WQM sites), "good" (50%), "fairly good" (14%), and "not good" (8%). Furthermore, we observed statistically significant correlations (p < 0.05; 0.4 ≤ r ≤ 0.7) between ASPT and all eight macroinvertebrate metrics examined, such as mayfly and stonefly richness, providing ecological implications of changes in ASPT.

Influence of COVID-19 pandemic on otitis media with effusion in children: A multicenter, retrospective survey in northern Japan.

OBJECTIVE: The purpose of this study is to compare patient trends in otitis media with effusion (OME) symptoms and diagnoses before and after the COVID-19 pandemic in order to investigate the effects of the coronavirus disease of 2019 (COVID-19). METHODS: A retrospective, multi-center, observational study was carried out between January 2018 and December 2022 at hospitals in the Iwate Prefecture with full-time doctors. All patients were initially separated into two groups, one for the pre-COVID-19 era (from January 2018 to June 2020), and the other for the COVID-19 era (from July 2020 to December 2022). RESULTS: In the pre-COVID-19 era, 132 patients had tympanostomy tubes (TT) placed, while 64 patients had them placed in the COVID-19 era. Between the pre-COVID-19 and COVID-19 eras, there were no statistically significant differences in terms of age, sex, side, craniofacial deformity, or adenoidectomy. Children in elementary school showed a greater decline than those in preschool (42-11 patients in elementary school (74%) and 49 to 32 patients in preschool school (35%); p = 0.025). CONCLUSIONS: The percentage of TT placements for OME dropped to roughly half during the COVID-19 epidemic. This was particularly obvious in elementary school students.

Effect of wearing masks on odor detection and recognition.

BACKGROUND: The effect of wearing masks on olfaction remains unclear. OBJECTIVES: This study aimed to clarify the differences between the effects of no masks, surgical masks, and N95 respirator masks by conducting both identification and threshold olfaction tests. METHODS: Young, healthy volunteers aged ≥ 18 years and < 30 years without awareness of apparent olfactory disorder were included. All participants filled out a questionnaire on olfaction and completed an acuity smell identification test (Open Essence test) and an olfactory threshold test (T&T olfactometry) while wearing no masks, surgical masks, or N95 respirator masks. RESULTS: In the Open Essence tests, the no-mask group score was significantly higher than those of the surgical- and N95-mask groups. Using T&T olfactometry, the median-detection threshold of the no-mask group was significantly lower than that of the surgical-mask group, and the surgical-mask group threshold was significantly lower than that of the N95-mask group. Similar patterns were observed for the median-recognition threshold. CONCLUSIONS: Wearing masks, especially an N95 mask, reduces the ability to detect and identify odors. This disadvantage should be considered by professionals such as healthcare workers, who require proper olfaction to perform appropriate tasks.

Venous Thromboembolism Following Lateral Lymph Node Dissection for Rectal Cancer.

BACKGROUND/AIM: Postoperative venous thromboembolism (VTE) is a well-recognized complication that leads to morbidity and mortality. Lateral lymph node dissection (LLND) for rectal cancer is thought to potentially increase the risk of VTE due to its technical complexity. However, the relationship between LLND and VTE remains inadequately understood. The aim of this study was to elucidate the impact of LLND on the incidence of postoperative VTE. PATIENTS AND METHODS: This is a retrospective analysis of patients who underwent rectal cancer resection between 2010 and 2018 to identify the risk factors associated with postoperative VTE. Patients were divided into two groups: those who underwent surgery with LLND (LLND+ group) and those who underwent surgery without LLND (LLND- group). RESULTS: A total of 543 patients were enrolled in this study, and 113 patients underwent surgery for rectal cancer with LLND. VTE developed in 8 patients (1.47%), with the incidence rates being 4.42% in the LLND+ group and 0.69% in the LLND- group, respectively (p=0.012). Three of 8 patients had developed severe postoperative complications, and the other two patients needed intraoperative repair of the iliac vein during LLND procedure. Multivariate analysis identified the incidence of postoperative complications and LLND as the independent risk factors of VTE. CONCLUSION: Patients undergoing rectal cancer surgery with LLND should be closely monitored for signs of VTE.

Epidemiology of postoperative bleeding after endoscopic nasal and sinus surgery and factors associated with bleeding.

PURPOSE: Endoscopic nasal and sinus surgery is a surgical procedure frequently performed by otolaryngologists. Postoperative bleeding is detrimental to both healthcare providers and patients. We investigated the epidemiology of postoperative bleeding during endoscopic nasal and sinus surgery and explored possible bleeding triggers. METHODS: We evaluated the patients who underwent endoscopic nasal and sinus surgery. Data regarding the age, sex, presence of hypertension, and abnormal coagulability, including oral anticoagulants, diagnoses, operative procedures, intraoperative use of drills and blood loss, and postoperative antimicrobial administration of eligible patients, were extracted from medical records and retrospectively reviewed. RESULTS: One hundred and eighty-six patients underwent endoscopic nasal or sinus surgery during the study period, and postoperative bleeding occurred in 9 patients (4.8%). Posterior nasal neurotomy (PNN) was the procedure most likely to cause postoperative bleeding (4 surgeries, 13.3%). Postoperative antimicrobial administration significantly reduced the incidence of postoperative bleeding (p = 0.04). CONCLUSIONS: Postoperative bleeding requiring intervention occurs in 4.8% of cases, and PNN is associated with a high risk of postoperative bleeding. Wound infection is a potential cause of postoperative bleeding, and antimicrobial administration should be considered in addition to local treatment.

Long-term Consequences on Soil Fungal Community Structure: Monoculture Planting and Natural Regeneration.

Understanding the regeneration and succession of belowground communities, particularly in forests, is vital for maintaining ecosystem health. Despite its importance, there is limited knowledge regarding how fungal communities change over time during ecosystem development, especially under different forest restoration strategies. In this study, we focused on two restoration methods used in northern Japan: monoculture planting and natural regeneration. We examined the responses of the fungal community to monoculture plantations (active tree planting) and naturally regenerated (passive regeneration) forests over a 50-year chronosequence, using natural forests as a reference. Based on DNA metabarcoding, we assessed the richness of fungal Operational Taxonomic Units (OTUs) and their dissimilarity. Our findings revealed that soil fungal richness remained stable after natural regeneration but declined in monoculture plantations, from 354 to 247 OTUs. While the compositional dissimilarity of fungal assemblages between monoculture plantations and natural forests remained consistent regardless of the time since tree planting, it significantly decreased after natural regeneration, suggesting recovery to a state close to the reference level. Notably, the composition of key functional fungal groups-saprotrophic and ectomycorrhizal- has increasingly mirrored that of natural forests over time following passive natural regeneration. In summary, our study suggests that monoculture plantations may not be effective for long-term ecosystem function and service recovery because of their limited support for soil fungal diversity. These results underscore the importance of natural regeneration in forest restoration and management strategies.

Exercise Capacity and Clinical Outcomes in Chronic Heart Failure Patients with Mild Tricuspid Regurgitation.

AIM: The present study aimed to investigate the impact of mild tricuspid regurgitation (TR) on the exercise capacity or clinical outcomes in patients with chronic heart failure (CHF). METHODS AND RESULTS: The study enrolled 511 patients with CHF who underwent cardiopulmonary exercise testing (CPET) between 2013 and 2018. The primary outcome was a composite of heart failure hospitalization and death. Patients with mild TR (n = 324) or significant TR (moderate or greater; n = 60) displayed worse NHYA class and reduced exercise capacity on CPET than those with non-TR (n = 127), but these were more severely impaired in patients with significant TR. A total of 90 patients experienced events over a median follow-up period of 3.3 (interquartile range 0.8-5.5) years. Patients with significant TR displayed a higher risk of events, while patients with mild TR had a 3.0-fold higher risk of events than patients with non-TR (hazard ratio (HR) 3.01; 95% confidence interval (CI), 1.50-6.07). Multivariate Cox regression analysis showed that, compared with non-TR, mild TR was associated with increased adverse events, even after adjustment for co-variates (HR 2.97; 95% CI, 1.35-6.55). CONCLUSIONS: TR severity was associated with worse symptoms, reduced exercise capacity, and poor clinical outcomes. Even patients with mild TR had worse clinical characteristics than those with non-TR.

MiR-181a targets STING to drive PARP inhibitor resistance in BRCA- mutated triple-negative breast cancer and ovarian cancer.

BACKGROUND: Poly (ADP-ribose) polymerase inhibitors (PARPi) are approved for the treatment of BRCA-mutated breast cancer (BC), including triple-negative BC (TNBC) and ovarian cancer (OvCa). A key challenge is to identify the factors associated with PARPi resistance; although, previous studies suggest that platinum-based agents and PARPi share similar resistance mechanisms. METHODS: Olaparib-resistant (OlaR) cell lines were analyzed using HTG EdgeSeq miRNA Whole Transcriptomic Analysis (WTA). Functional assays were performed in three BRCA-mutated TNBC cell lines. In-silico analysis were performed using multiple databases including The Cancer Genome Atlas, the Genotype-Tissue Expression, The Cancer Cell Line Encyclopedia, Genomics of Drug Sensitivity in Cancer, and Gene Omnibus Expression. RESULTS: High miR-181a levels were identified in OlaR TNBC cell lines (p = 0.001) as well as in tumor tissues from TNBC patients (p = 0.001). We hypothesized that miR-181a downregulates the stimulator of interferon genes (STING) and the downstream proinflammatory cytokines to mediate PARPi resistance. BRCA1 mutated TNBC cell lines with miR-181a-overexpression were more resistant to olaparib and showed downregulation in STING and the downstream genes controlled by STING. Extracellular vesicles derived from PARPi-resistant TNBC cell lines horizontally transferred miR-181a to parental cells which conferred PARPi-resistance and targeted STING. In clinical settings, STING levels were positively correlated with interferon gamma (IFNG) response scores (p = 0.01). In addition, low IFNG response scores were associated with worse response to neoadjuvant treatment including PARPi for high-risk HER2 negative BC patients (p = 0.001). OlaR TNBC cell lines showed resistance to platinum-based drugs. OvCa cell lines resistant to platinum showed resistance to olaparib. Knockout of miR-181a significantly improved olaparib sensitivity in OvCa cell lines (p = 0.001). CONCLUSION: miR-181a is a key factor controlling the STING pathway and driving PARPi and platinum-based drug resistance in TNBC and OvCa. The miR-181a-STING axis can be used as a potential marker for predicting PARPi responses in TNBC and OvCa tumors.

Association of coronary plaque morphology with inflammatory biomarkers and target lesion revascularization in patients with chronic coronary syndrome: an optical coherence tomography study.

BACKGROUND: The characteristics of high-risk coronary atherosclerosis evaluated using optical coherence tomography (OCT) can have a prognostic role. Inflammatory biomarkers may be related to the severity of coronary artery disease. This study investigated the association of high-risk morphological features of coronary plaques on OCT with circulating levels of inflammatory biomarkers and target lesion revascularization (TLR). MATERIALS AND METHODS: We prospectively analyzed the data of 30 consecutive patients with chronic coronary syndrome who underwent percutaneous coronary intervention (PCI) using OCT. The levels of interleukin-6, tumor necrosis factor-alpha, high-sensitivity C-reactive protein, pentraxin 3, vascular endothelial growth factor, and monocyte chemoattractant protein-1 (MCP-1) were measured in plasma samples. Coronary plaque characteristics were scored quantitatively in the form of coronary plaque risk score (CPRS). The estimated high-risk plaque characteristics for TLR were plaque rupture, plaque erosion, calcified nodule, lipid-rich plaque, thin-cap fibroatheroma, cholesterol crystals, macrophage infiltration, microchannels, calcification angle >90°, and microcalcifications. Each high-risk feature carries 1 point. Patients were defined as having a low CPRS (CPRS ≤3) or a high CPRS (CPRS ≥4). RESULTS: The primary outcome was TLR. TLR occurred in 6 (20%) patients within 15 months of PCI. High CPRS on OCT was directly correlated with TLR (P=0.029). In logistic regression analysis, CPRS was associated with TLR (odds ratio, 10.0; 95% confidence interval, 1.34-74.5). Serum MCP-1 level was significantly correlated with the CPRS (P=0.020). CONCLUSIONS: In patients with chronic coronary syndrome, CPRS may be a surrogate predictor of TLR. Serum MCP-1 may aid in the detection of high-risk coronary atherosclerosis.