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ObjectivesTo assess the feasibility of a CNN-based liver registration algorithm to generate difference maps for visual display of spatiotemporal changes in liver PDFF, without needing manual annotations.MethodsThis retrospective exploratory study included 25 patients with suspected or confirmed NAFLD, who underwent PDFF-MRI at two time points at our institution. PDFF difference maps were generated by applying a CNN-based liver registration algorithm, then subtracting follow-up from baseline PDFF maps. The difference maps were post-processed by smoothing (5 cm2 round kernel) and applying a categorical color scale. Two fellowship-trained abdominal radiologists and one radiology resident independently reviewed difference maps to visually determine segmental PDFF change. Their visual assessment was compared with manual ROI-based measurements of each Couinaud segment and whole liver PDFF using intraclass correlation (ICC) and Bland-Altman analysis. Inter-reader agreement for visual assessment was calculated (ICC).ResultsThe mean patient age was 49 years (12 males). Baseline and follow-up PDFF ranged from 2.0 to 35.3% and 3.5 to 32.0%, respectively. PDFF changes ranged from - 20.4 to 14.1%. ICCs against the manual reference exceeded 0.95 for each reader, except for segment 2 (2 readers ICC = 0.86-0.91) and segment 4a (reader 3 ICC = 0.94). Bland-Altman limits of agreement were within 5% across all three readers. Inter-reader agreement for visually assessed PDFF change (whole liver and segmental) was excellent (ICCs > 0.96), except for segment 2 (ICC = 0.93).ConclusionsVisual assessment of liver segmental PDFF changes using a CNN-generated difference map strongly agreed with manual estimates performed by an expert reader and yielded high inter-reader agreement.Key points• Visual assessment of longitudinal changes in quantitative liver MRI can be performed using a CNN-generated difference map and yields strong agreement with manual estimates performed by expert readers.

BackgroundLiver alignment between series/exams is challenged by dynamic morphology or variability in patient positioning or motion. Image registration can improve image interpretation and lesion co-localization. We assessed the performance of a convolutional neural network algorithm to register cross-sectional liver imaging series and compared its performance to manual image registration.MethodsThree hundred fourteen patients, including internal and external datasets, who underwent gadoxetate disodium-enhanced magnetic resonance imaging for clinical care from 2011 to 2018, were retrospectively selected. Automated registration was applied to all 2,663 within-patient series pairs derived from these datasets. Additionally, 100 within-patient series pairs from the internal dataset were independently manually registered by expert readers. Liver overlap, image correlation, and intra-observation distances for manual versus automated registrations were compared using paired t tests. Influence of patient demographics, imaging characteristics, and liver uptake function was evaluated using univariate and multivariate mixed models.ResultsCompared to the manual, automated registration produced significantly lower intra-observation distance (p < 0.001) and higher liver overlap and image correlation (p < 0.001). Intra-exam automated registration achieved 0.88 mean liver overlap and 0.44 mean image correlation for the internal dataset and 0.91 and 0.41, respectively, for the external dataset. For inter-exam registration, mean overlap was 0.81 and image correlation 0.41. Older age, female sex, greater inter-series time interval, differing uptake, and greater voxel size differences independently reduced automated registration performance (p ≤ 0.020).ConclusionA fully automated algorithm accurately registered the liver within and between examinations, yielding better liver and focal observation co-localization compared to manual registration.

Introduction: Leg length is an important consideration in total hip arthroplasty (THA) as leg length discrepancies (LLD) after THA cause poor outcomes and medical litigation. This study aimed to investigate the accuracy of computed tomography (CT)-based navigation with augmented reality (AR) technology for measuring intra-operative leg length change using anteroposterior radiography (two-dimensional, 2D) and CT (three-dimensional, 3D). Materials and methods: This study included 71 patients (75 hips) who underwent primary cementless THA in the supine position between June 2022 and November 2023 using the HoloNavi One. To assess the accuracy of the HoloNavi One based on 2D and 3D measurements, the absolute error between the intra-operative leg length change and the 2D and 3D measurements was evaluated, and the correlations were investigated. Additionally, factors affecting the absolute error were examined using multivariate analysis. Results: The mean intra-operative leg length change when using the HoloNavi One was 6.5 ± 5.0 mm, while the mean leg length change on the 2D and 3D measurements were 5.9 ± 4.8 mm and 4.6 ± 5.7 mm, respectively. The mean absolute errors were 2.3 ± 2.7 mm between the HoloNavi One and 2D measurements, and 3.8 ± 3.3 mm between HoloNavi One and 3D measurements. The absolute errors in leg length changes for the 3D measurements were greater than those for the 2D measurements (p < 0.01). Positive correlations of leg length changes were found between the HoloNavi One and the 2D and 3D measurements. In the multiple regression analysis, no significant factors affecting the absolute error were identified in either the 2D or 3D measurements. Conclusions: CT-based navigation with AR technology in the supine position provided acceptable accuracy for leg length change measurements. [ABSTRACT FROM AUTHOR]

The iron sand around Mt. Aburayama (Fukuoka, Japan), where various ancient iron‐making sites are located, was investigated to establish a research infrastructure for identification of the raw material used in the archeological iron artifacts excavated from this area. Iron sand samples were magnetically collected from the rivers flowing in this area and nearby outcrop soil. The samples were qualitatively analyzed using Mössbauer spectroscopy and x‐ray diffractometry to identify the minerals present inside them. Additionally, the elemental concentrations in these samples were determined using x‐ray fluorescence spectrometry. The iron sand samples were characterized by comparing them with those from other Japanese regions using scatter diagrams developed based on the elemental concentrations in the samples. The scatter diagrams showed clear distinctions between the iron sand samples from the Mt. Aburayama area and other Japanese regions. These diagrams may enable us to clarify the relationship between the iron sand and archeological iron artifacts found in the vicinity of Mt. Aburayama. [ABSTRACT FROM AUTHOR]

Chloroplast starch granules (cpSGs) store energy harvested through photosynthesis in plants, and cpSG dynamics have important roles in plant energy metabolism and stress responses. To date, cpSGs have been visualized using several methods, such as iodine staining; however, no method can be used to specifically visualize cpSGs in living cells from various plant species. Here, we report a simple method to visualize cpSGs in living plant cells in various species by staining with fluorescein, a commonly used fluorescent dye. We show that fluorescein is taken up into chloroplasts and interacts with cpSGs similarly to iodine. Fluorescein also interacts with refined starch in vitro. Using a fluorescein derivative for ultrabright cpSG imaging, we produced high-quality 3D reconstructions of cpSGs and evaluated their accumulation in multiple plant species. As fluorescein is well known and readily purchasable, our fluorescein-based staining method should contribute to all research regarding starch. Fluorescein stains chloroplast starch granules in living plant cells and refined starch in vitro by entering the amylose and amylopectin vacancy in a similar way as iodine. [ABSTRACT FROM AUTHOR]

Background and Objective: The lung immune prognostic index (LIPI), a simple index calculated from the blood lactate dehydrogenase level and derived neutrophil‐to‐lymphocyte ratio, is thought to be associated with host immune status. However, the utility of LIPI in patients with idiopathic interstitial pneumonias (IIPs) is unknown. Methods: In this multicentre, retrospective, observational study, an association between LIPI and the survival of patients with IIPs was evaluated. Results: Exploratory and validation cohorts consisting of 460 and 414 patients with IIPs, respectively, were included (159 and 159 patients had idiopathic pulmonary fibrosis [IPF], and 301 and 255 had non‐IPF, respectively). In the exploratory cohort, patients with IPF and a low LIPI had significantly better survival than those with a high LIPI (median of 5.6 years vs. 3.9 years, p = 0.016). The predictive ability of LIPI for the survival of patients with IPF was validated in the validation cohort (median of 8.5 years vs. 4.4 years, p = 0.003). In a multivariate Cox proportional hazard analysis, LIPI was selected as an independent predictive factor for the survival of IPF patients. There was no significant association between LIPI and survival of non‐IPF patients in the exploratory and validation cohorts. Conclusion: The LIPI was a predictive factor for the survival of patients with IPF and could aid the management of IPF. [ABSTRACT FROM AUTHOR]

Aim: To determine risk factors associated with hepatocellular carcinoma (HCC) development following direct‐acting antiviral (DAA) therapy. Methods: We enrolled patients with chronic hepatitis C who underwent direct‐acting antiviral therapy and achieved sustained virologic response at 12 weeks between 2012 and 2018. Subsequently, patients were followed up. The primary endpoint was the development of HCC or the date of the last follow up when the absence of HCC was confirmed. Uni‐ and multivariate Cox proportional hazards models were used to identify factors contributing to HCC development, including gadoxetic acid‐enhanced magnetic resonance imaging findings. The cumulative incidence rates of HCC development were calculated using the Kaplan–Meier method, and differences between groups were assessed using the log‐rank test. Results: The final study cohort comprised 482 patients (median age 70.5 years; 242 men). The median follow‐up period was 36.8 months. Among 482 patients, 96 developed HCC (19.9%). The 1‐, 3‐, and 5‐year cumulative rates of HCC development were 4.9%, 18.6%, and 30.5%, respectively. Multivariate analysis revealed that age, male sex, history of HCC, and hepatobiliary phase hypointense nodules without arterial phase hyperenhancement were independent risk factors significantly associated with HCC development (p < 0.001–0.04). The highest risk group included patients with both a history of HCC and the presence of hepatobiliary phase hypointense nodules without arterial phase hyperenhancement (the 1‐ and 3‐year cumulative HCC development rates were 14.2% and 62.2%, respectively). Conclusion: History of HCC and presence of hepatobiliary phase hypointense nodules without arterial phase hyperenhancement were strong risk factors for HCC development following direct‐acting antiviral therapy. [ABSTRACT FROM AUTHOR]

Background: In transthyretin cardiac amyloidosis (ATTR-CA), 99mTc-pyrophosphate myocardial scintigraphy (99mTc-PYP) is a diagnostic tool that utilizes visual and quantitative evaluation. However, false positive cases can occur because of tracer accumulation in the blood. We investigated the effectiveness of the heart-to-mediastinum (H/M) ratio of 99mTc-PYP in ATTR-CA diagnosis. Methods: We retrospectively included 164 patients who underwent 99mTc-PYP single-photon emission computed tomography/computed tomography between March 2019 and January 2022. The diagnostic accuracy of ATTR-CA was examined by the heart-to-contralateral lung (H/CL) and H/M ratio calculated at 3 hours post-tracer administration. Results: After the exclusion of patients who did not undergo endomyocardial biopsy, 30 patients (15 each with ATTR-CA and without ATTR-CA) were included. The receiver operating characteristic curve used to distinguish ATTR-CA from non-ATTR-CA patients revealed an area under the curve of 0.986 and 0.943, respectively. A H/M ratio of > 1.41 identified ATTR-CA patients with a sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 100, 93.3, 93.3, and 100%, respectively. Conversely, an H/CL ratio of > 1.3 identified ATTR-CA patients with 100% sensitivity, 40.0% specificity, 62.5% PPV, and 100% NPV. Conclusion: The H/M ratio obtained at 3 hours post-injection has the potential to be a novel indicator for ATTR-CA. [ABSTRACT FROM AUTHOR]