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The departure of the latest FNAL experimental average for the muon anomalous magnetic moment a μ = (g μ - 2) / 2 measurements, having increased from 4.2 σ (Abi et al. in Measurement of the positive muon anomalous magnetic moment to 0.46 ppm, , 2021) to 5.0 σ (Muon g-2, D.P. Aguillard et al. in Measurement of the positive muon anomalous magnetic moment to 0.20 ppm, , 2023) with respect to the white paper (WP) consensus (Aoyama et al. in Phys Rep 887:1, , 2020), may indicate a hint for new physics. As the most delicate piece of a μ is its leading-order hadronic vacuum polarization (HVP) part a μ H V P - L O , methods to ascertain its theoretical value are crucial to appropriately interpreting this departure from the measurement. We, therefore, propose to closely examine the dipion spectra from the η / η ′ → π + π - γ decays in the hidden local symmetry (HLS) context using its BHLS 2 broken variant. We thus have at our disposal a framework where the close relationship of the dipion spectra from the η / η ′ and τ decays and of the e + e - → π + π - annihilation can be simultaneously considered. A special focus is given to the high-statistics dipion spectra from the η decay collected by the KLOE/KLOE2 Collaboration and η ′ decay collected by the BESIII Collaboration, and it is shown that the BHLS 2 framework provides a fair account of their dipion spectra. More precisely, it is first proven that a single Omnès representation real polynomial is required, common to both the η and η ′ dipion spectra. Moreover, it is shown that fits involving the η / η ′ / τ dipion spectra, and excluding the e + e - → π + π - annihilation data, allow for a prediction of the pion vector form factor data F π (s) which agrees fairly well with the usual dipion spectra collected in the e + e - → π + π - annihilation channel. Even if more precise η / η ′ / τ dipion spectra would help to be fully conclusive, this confirms the dispersive approach results for a μ H V P - L O and points toward a common non-experimentally dependent origin to this tension with the now well-accepted LQCD result. [ABSTRACT FROM AUTHOR]

The generic hidden local symmetry (HLS) model has recently given rise to its BHLS 2 variant, defined by introducing symmetry breaking mostly in the vector meson sector; the central mechanism is a modification of the covariant derivative at the root of the HLS approach. However, the description of the τ dipion spectra, especially the Belle one, is not fully satisfactory, whereas the simultaneous dealing with its annihilation sector ( e + e - → π + π - / π + π - π 0 / π 0 γ / η γ / K + K - / K L K S ) is optimum. We show that this issue is solved by means of an additional breaking term which also allows us to consistently include the mixing properties of the [ π 0 , η , η ′ ] system within this extended BHLS 2 ( EBHLS 2 ) scope. This mechanism, an extension of the usual 't Hooft determinant term, only affects the kinetic energy part of the BHLS 2 Lagrangian. One thus obtains a fair account for the τ dipion spectra which complements the fair account of the annihilation channels already reached. The Belle dipion spectrum is found to provide evidence in favor of a violation of the conserved vector current (CVC) in the τ lepton decay; this evidence is enforced by imposing the conditions < 0 | J μ q | [ q ′ q ′ ¯ ] (p) > = i p μ f q δ q q ′ , { [ q q ¯ ] , q = u , d , s } on EBHLS 2 axial current matrix elements. EBHLS 2 is found to recover the usual (completed) formulae for the [ π 0 , η , η ′ ] mixing parameters, and the global fits return mixing parameter values in agreement with expectations and better uncertainties. Updating the muon hadronic vacuum polarization (HVP), one also argues that the strong tension between the KLOE and BaBar pion form factors imposes to provide two solutions, namely a μ H V P - L O (KLOE) = 687.48 ± 2.93 and a μ H V P - L O (BaBar) = 692.53 ± 2.95 , in units of 10 - 10 , rather than some combination of these. Taking into account common systematics, their differences from the experimental BNL-FNAL average value exhibit significance > 5.4 σ (KLOE) and > 4.1 σ (BaBar), with fit probabilities favoring the former. [ABSTRACT FROM AUTHOR]

Opinion Statement: Therapies for brain metastasis continue to evolve as the life expectancies for patients have continued to prolong. Novel advances include the use of improved technology for radiation delivery, surgical guidance, and response assessment, along with systemic therapies that can pass through the blood brain barrier. With increasing complexity of treatments and the increased need for salvage treatments, multi-disciplinary management has become significantly more important., (© 2024. The Author(s).)

Introduction: Arthroscopic training includes successive stages of observation, reproduction and then repetition. Learning through simulation in 2D virtual reality makes it possible to repeat these different stages to enhance the learner's experience in complete safety and a shorter timeframe. Some procedures require inversion of the optical and instrumental approaches in the axial plane, disrupting the existing psychomotor and technical skills. The objective of this study was to compare the degree of difficulty and the distribution of results for the same exercise carried out alternately in classical holding and inverted holding of the instruments in a cohort of novice learners., Materials and Methods: Twenty-two medical students, novices in arthroscopic surgery, participated in the study. Each performed an exercise consisting of grasping ten targets with arthroscopic forceps and placing them in a basket on the VirtaMed ArthroS™ simulator. The exercise was performed with the scope and grasping instrument pointed away from the operator, "catch the stars front" (CTSF), then directed towards the operator, "catch the stars back" (CTSB). The simulator recorded several parameters making up an overall composite score ("overall performance score", OPS) out of 120 points. Voluntary abandonment of the exercise was also collected., Results: All students completed the CTSF exercise but 6 dropped out of the CTSB exercise (27%, p=0.01). In the CTSF exercise, the average OPS was higher with 45.9 points versus 22.8 points in the CTSB exercise (p<0.001). By detailing the components of the OPS score, the parameters of interest on the Fundamentals of Arthroscopic Training (FAST) module of the simulator included: the distance traveled by the scope and the grasping forceps was significantly greater in the CTSB group (p<0.001), the duration of the exercise was significantly greater in the CTSB group (p<0.001), the time spent with the instruments in the videoscopic field was significantly lower in the CTSB group (p=0.001) and finally the absence of a significant difference in the camera alignment compared to the horizontal plane between the two groups., Conclusion: The exercise with the instruments directed towards the operator is more difficult with a greater distribution for all the secondary criteria except for the camera alignment, which suggests that it could be more discriminating. The dropout rate is also higher. It would therefore be interesting to introduce CTSB type training in initial training programs in arthroscopy., Level of Evidence: III, comparative prospective study., (Copyright © 2023 Elsevier Masson SAS. All rights reserved.)

Introduction: Melanocytic nevi present microscopic patterns, which differ in their associated melanoma risk, and can be non-invasively recognized under Reflectance Confocal Microscopy (RCM)., Aims: To train a Generative Adversarial Network (GAN) deep-learning model to produce synthetic images that recapitulate RCM patterns of nevi, enabling reliable classification by human readers and by a Convolutional Neural Network (CNN) computer model., Methods: A dataset of RCM images of nevi, presenting a uniform pattern, were chosen and classified into one of three patterns - Meshwork, Ring or Clod. Images were used for training a GAN model, which in turn, produced synthetic images recapitulating RCM patterns of nevi. A random sample of synthetic images was classified by two independent human readers and by a CNN model. Human and computer-model classifications were compared., Results: The training set for the GAN model included 1496 RCM images, including 977 images (65.3%) with Meshwork pattern, 261 (17.4%) with Ring and 258 (17.2%) with Clod pattern. The GAN model produced 6000 synthetic RCM-like images. Of these, 302 images were randomly chosen and classified by human readers, including 83 (27.5%) classified as Meshwork, 131 (43.4%) as Ring, and 88 (29.1%) as Clod pattern. Human inter-observer concordance in pattern classification was 91.7%, and human-to-CNN concordance was 87.7%., Conclusions: We demonstrate feasibility of producing synthetic images, which recapitulate RCM patterns of nevi and can be reproducibly recognized by human readers and by deep-learning models. Synthetic image datasets may allow teaching RCM patterns to novices, training of computer models, and data sharing between research centers.

Introduction: Three-dimensional (3D) planning and patient-specific surgical guides are increasingly used in the treatment of skeletal deformities. The present study hypothesis was that they are reliable in forearm osteotomy in children, with low morbidity., Material and Methods: Twenty-there children with one or several osteotomies to correct forearm deformities were retrospectively included: 9 (20 osteotomies) with surgical guide (G+), and 14 (28 osteotomies) without (G-). Etiologies comprised 8 cases of Madelung disease (3G+, 5G-) and 15 of post-traumatic malunion (6G+, 9G-). Mean age at surgery was 14.8±1.9 years. The patient-specific 3D-printed polyamide guides were produced from 3D virtual models based on 3D CT reconstruction. Mean follow-up was 22.1±13.6 months., Results: Mean correction error was 5.3°±4.1 and 4.2°±4.1 in the frontal and sagittal planes respectively in G+ (p=0.6). Surgery time was significantly shorter in G+, by a mean 42min (p=0.02). Mean total radiation dose (preoperative CT+intraoperative fluoroscopy) was significantly higher in G+ (p<0.0001). Complications rates were similar between groups. Improvement in PRWE score was significantly greater in G+., Conclusion: The present preliminary results were encouraging. 3D planning and patient-specific surgical guides can be used in the treatment of forearm deformity in children., Level of Evidence: III; retrospective cohort study., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

Background and Purpose: Transient loss of consciousness is commonly evaluated in the emergency department. Although typically caused by epileptic seizure, syncope, or psychogenic nonepileptic seizure, the underlying etiology is frequently misdiagnosed. Lateral tongue bites are reportedly a specific clinical finding of seizure. We have observed tongue signal abnormality suggesting bite injury on brain MR imaging after seizures. We hypothesized an association between tongue signal abnormality and seizure diagnosis among patients in the emergency department imaged for transient loss of consciousness. Our purposes were to determine the prevalence of tongue signal abnormality among this population and the predictive performance for seizure diagnosis., Materials and Methods: For this retrospective study including 82 brain MR imaging examinations, 2 readers independently assessed tongue signal abnormality on T2-weighted and T2-weighted FLAIR images. Discrepancies were resolved by consensus, and interrater reliability (Cohen κ) was calculated. The final diagnosis was recorded. Proportions were compared using the Fisher exact test., Results: Tongue signal abnormality was present on 19/82 (23%) MR imaging examinations. Interrater reliability was "substantial" (κ = 0.77). Seizure was diagnosed among 18/19 (95%) patients with tongue signal abnormality and 29/63 (46%) patients without it ( P  < .001). In our cohort, tongue signal abnormality conveyed 97% specificity, 95% positive predictive value, and 63% accuracy for seizure diagnosis., Conclusions: Tongue signal abnormality was observed in 23% of the study cohort and conveyed 97% specificity and 95% positive predictive value for seizure diagnosis. By assessing and reporting tongue signal abnormality, radiologists may facilitate a timely and accurate diagnosis of seizure among patients imaged for transient loss of consciousness., (© 2021 by American Journal of Neuroradiology.)