Correction: MR-guided focused ultrasound technique in functional neurosurgery: targeting accuracy

Stereotactic radiosurgery (SRS), a noninvasive technique that delivers a high dose of ionizing radiation to a precisely defined focal target volume, is foundational to modern neuro-oncology and functional neurosurgery. SRS provides highly accurate, noninvasive treatment for a range of intracranial conditions, including malignant and benign tumors, vascular malformations such as arteriovenous malformations (AVMs), and movement or functional disorders like trigeminal neuralgia. Despite a well-documented safety record and demonstrable efficacy, significant disparities in accessibility persist across global, geographic, and socioeconomic lines. This editorial aims to explore ways in which health policy innovation, international collaboration, and investment into mobile or modular radiosurgery platforms can help bridge gaps and promote access to SRS interventions for underserved populations. Addressing these disparities requires a thoughtful discourse on outcome equity and the ethical imperative to ensure universal access to neurosurgical care.

LETTERS TO THE EDITOR Letters are selected for their expected interest for our readers. Some letters are sent to reviewers for advice; some are accepted or declined by the editor without review. Letters must be brief and may be edited, subject to the author’s approval of significant changes. Although some comments on published articles and notes may be appropriate as letters, most such comments are reviewed according to a special procedure and appear, if accepted, in the Notes and Discussions section. 共See the ‘‘Statement of Editorial Policy’’ in the January issue.兲 Running controversies among letter writers will not be published. SOLAR BLACKBODY SPECTRUM AND THE EYE’S SENSITIVITY Virginia Trimble’s wonderful article on cosmology 共December 2002, pp. 1175– 1183兲 states that ‘‘any blackbody source at a temperature near that of the sun...is bound to look white. This is not a coincidence, but a product of evolution; our eyes are most sensitive at the peak of the solar spectrum.’’ I had believed this for years, until I read Bernard Soffer and David Lynch’s article in AJP, November 1999, pp. 946 –953. They show that the quoted statement is mislead- ing and erroneous, because the spectral ra- diance versus wavelength graph is a density distribution function whose peak position changes when plotted in terms of a differ- ent variable such as frequency, while the eye’s sensitivity is an ordinary function. Furthermore, ‘‘the eye does not appear to be optimized for detection of the available sunlight. ...It is likely that we are viewing the world with a souvenir of the human evolutionary voyage.’’ Art Hobson University of Arkansas Fayetteville, Arkansas 72701 Electronic mail: ahobson@uark.edu AUTHOR’S RESPONSE Professor Hobson is, of course, right about the details of this issue. But what I 共and many others兲 have always meant by Am. J. Phys. 71 共4兲, April 2003 the broad remark is that there are good rea- sons that we do not have eyes that are pri- marily sensitive to far IR, UV, mm, radio, or x-ray emission. Although astronomers sometimes speak of the sun as belonging to a category of ‘‘yellow’’ stars, people who measure color for a living 共for example, my father was a chemist specializing in color- forming materials兲 define ‘‘white’’ as the appearance of things like clean paper in full, clear sunlight. Virginia Trimble Department of Physics and Astronomy University of California Irvine, California 92697 GATEWAYS INTO ELECTRONICS In the review of my book, Gateways into Electronics, 1 that appeared in the May 2001 issue of AJP, 2 the reviewer ponders at length about its suitability for his students at UC, Berkeley and decides that Gateways is not for them. This choice is of course his prerogative. He does, however, make a statement to which I would like to respond, namely, that Gateways is not suitable for an introductory course. As I wrote in the Preface, the chapters in Gateways are of two distinct types: elemen- tary chapters that deal with standard topics such as circuit theory and transistor ampli- fiers, and more advanced chapters that pro- vide the mathematical and physical under- http://ojps.aip.org/ajp/ pinning for the elementary chapters or deal with complementary topics such as trans- mission lines and signal recovery. For ex- ample, Chapter 1 discusses simple linear systems to the extent required in subse- quent elementary chapters and involves only complex numbers and linear differen- tial equations, whereas Chapter 2 is a full- blown exposition of generalized functions and integral transforms that leads to the convolution theorem for linear systems and Shannon’s sampling theorem. Chapter 2 is intended for those who might eventually find it of interest, but in a first reading, or if only an introductory treatment is desired, it can be skipped or postponed with no loss of continuity. Gateways has its origins in an introduc- tory course for students straight out of high school, so that although it is true that the text has become more mathematical and now has juniors in physics preferably in mind, its thrust has not changed and the elementary chapters remain, as they were at the outset, quite accessible to beginners. Peter C. Dunn, Gateways into Electronics 共Wiley, New York, 2000兲. A brief description and a table of contents are available at 具www.amazon.com典. Joel Fajans, review of Ref. 1, Am. J. Phys. 69, Peter C. Dunn 13A Ila Road Saugus, Massachusetts 01906 Electronic mail: pcdunn@alum.mit.edu © 2003 American Association of Physics Teachers

BackgroundThe World Health Organization recently made a recommendation supporting ‘culturally-appropriate’ maternity care services to improve maternal and newborn health. This recommendation results, in part, from a systematic review we conducted, which showed that interventions to provide culturally-appropriate maternity care have largely improved women’s use of skilled maternity care. Factors relating to the implementation of these interventions can have implications for their success. This paper examines stakeholders’ perspectives and experiences of these interventions, and facilitators and barriers to implementation; and concludes with how they relate to the effects of the interventions on care-seeking outcomes.MethodsWe based our analysis on 15 papers included in the systematic review. To extract, collate and organise data on the context and conditions from each paper, we adapted the SURE (Supporting the Use of Research Evidence) framework that lists categories of factors that could influence implementation. We considered information from the background and discussion sections of papers included in the systematic review, as well as cost data and qualitative data when included.ResultsWomen’s and other stakeholders’ perspectives on the interventions were generally positive. Four key themes emerged in our analysis of facilitators and barriers to implementation. Firstly, interventions must consider broader economic, geographical and social factors that affect ethnic minority groups’ access to services, alongside providing culturally-appropriate care. Secondly, community participation is important in understanding problems with existing services and potential solutions from the community perspective, and in the development and implementation of interventions. Thirdly, respectful, person-centred care should be at the core of these interventions. Finally, cohesiveness is essential between the culturally-appropriate service and other health care providers encountered by women and their families along the continuum of care through pregnancy until after birth.ConclusionSeveral important factors should be considered and addressed when implementing interventions to provide culturally-appropriate care. These factors reflect more general goals on the international agenda of improving access to skilled maternity care; providing high-quality, respectful care; and community participation.

Rethinking the Ph.D. dissertation in botany: Widening the circle.

Doppler myocardial imaging: A new method of data acquisition for three-dimensional echocardiography

Individualized altered fractionation as a more effective radiotherapy for non-small cell lung cancer.

Novel Approach to Three-Dimensional Echocardiographic Quantification of Right Ventricular Volumes and Function from Focused Views.

The Quality Outcomes Database (QOD) was established in 2012 by the NeuroPoint Alliance, a nonprofit organization supported by the American Association of Neurological Surgeons. Currently, the QOD has launched six different modules to cover a broad spectrum of neurosurgical practice-namely lumbar spine surgery, cervical spine surgery, brain tumor, stereotactic radiosurgery (SRS), functional neurosurgery for Parkinson's disease, and cerebrovascular surgery. This investigation aims to summarize research efforts and evidence yielded through QOD research endeavors. The authors identified all publications from January 1, 2012, to February 18, 2023, that were produced by using data collected prospectively in a QOD module without a prespecified research purpose in the context of quality surveillance and improvement. Citations were compiled and presented along with comprehensive documentation of the main study objective and take-home message. A total of 94 studies have been produced through QOD efforts during the past decade. QOD-derived literature has been predominantly dedicated to spinal surgical outcomes, with 59 and 22 studies focusing on lumbar and cervical spine surgery, respectively, and 6 studies focusing on both. More specifically, the QOD Study Group-a research collaborative between 16 high-enrolling sites-has yielded 24 studies on lumbar grade 1 spondylolisthesis and 13 studies on cervical spondylotic myelopathy, using two focused data sets with high data accuracy and long-term follow-up. The more recent neuro-oncological QOD efforts, i.e., the Tumor QOD and the SRS Quality Registry, have contributed 5 studies, providing insights into the real-world neuro-oncological practice and the role of patient-reported outcomes. Prospective quality registries are an important resource for observational research, yielding clinical evidence to guide decision-making across neurosurgical subspecialties. Future directions of the QOD efforts include the development of research efforts within the neuro-oncological registries and the American Spine Registry-which has now replaced the inactive spinal modules of the QOD-and the focused research on high-grade lumbar spondylolisthesis and cervical radiculopathy.

Due to the correlated nature of diffused light, the problem of reconstructing optical properties using diffuse optical tomography (DOT) is ill-posed. US-, MRI- or x-ray-guided DOT approaches can reduce the total number of parameters to be estimated and improve optical reconstruction accuracy. However, when the target volume is large, the number of parameters to estimate can exceed the number of measurements, resulting in an underdetermined imaging model. In such cases, accurate image reconstruction is difficult and regularization methods should be employed to obtain a useful solution. In this manuscript, a simple two-step reconstruction method that can produce useful image estimates in DOT is proposed and investigated. In the first step, a truncated Moore-Penrose Pseudoinverse solution is computed to obtain a preliminary estimate of the image that can be reliably determined from the measured data; subsequently, this preliminary estimate is incorporated into the design of a penalized least squares estimator that is employed to compute the final image estimate. By use of phantom data, the proposed method was demonstrated to yield more accurate images than those produced by conventional reconstruction methods. The method was also evaluated with clinical data that included 10 benign and 10 malignant cases. The capability of reconstructing high contrast malignant lesions was demonstrated to be improved by use of the proposed method.

In conventional fluorescence molecular tomography, the distribution of fluorescent contrast agents is reconstructed with the assumption of constant concentration during data acquisition for each image frame. However, the concentration of fluorescent contrast target is usually time-varying in experiments or in-vivo studies. In this case, the reconstruction methods cannot be directly applied to the fluorescence measurements without considering the time-varying effects of concentration. We propose a modified forward model by dividing the fluorescence yield distribution into two parts: one is a constant representing the spatial distribution of the fluorescent target and the other is an impact factor representing the effects of the concentration change and other possible factors. By extracting spatial distribution information from the reconstruction result, the location and volume of the fluorescent target can be obtained accurately. Both simulation and phantom experiments are carried out and the results indicate that, by using the modified forward model, the quality of reconstruction could be significantly improved in terms of accurate localization and strong anti-noise ability.

Carbon-Ion Pencil Beam Scanning Treatment With Gated Markerless Tumor Tracking: An Analysis of Positional Accuracy

Optoacoustic Tomography (OAT) is a hybrid imaging modality that combines the advantages of both optical imaging and ultrasound imaging techniques. Most existing reconstruction algorithms for OAT assume pointlike transducers, which may result in conspicous image blurring and distortions in certain applications. In this work, a new imaging model that incorporates the transducer response is employed for image reconstruction. Computer-simulation studies demonstrate that the new reconstruction method can effectively compensate for image resolution degradation associated with the transducer response.

There is increasing interest in natural bioactive compounds for prophylactic and therapeutic use. In Georgia, many endemic plant species remain underexplored with modern analytical methods. This study focused on analyzing the chemical composition of wild Senecio platyphyllus and both wild and cultivated forms of Prunus laurocerasus, species native to Georgia. Additionally, the research aimed to develop sustainable extraction technologies aligned with circular economy principles-an area largely unaddressed in the region. Classical extraction methods were compared with high-pressure, ultrasound, and supercritical fluid techniques to determine optimal conditions. A key objective was to optimize alkaloid extraction from S. platyphyllus and refine both qualitative and quantitative analysis. The resulting protocol reduced extraction time from 30 hours to just 2h. Using UPLC-PDA-MS (ultra-performance liquid chromatography with photodiode array and mass spectrometry), main alkaloids were identified in only 45 minutes through three 15-minute chromatographic runs. This significantly improved analytical speed and accuracy. A phenyl column combined with a 0.1% formic acid–deionized water (A) and acetonitrile (B) gradient system allowed efficient separation of alkaloids and other bioactive compounds. In P. laurocerasus, high levels of chlorogenic and neochlorogenic acids, along with cyanide-derived anthocyanins, were detected in both fruit and bark. To promote sustainability, green extraction methods using water–alcohol mixtures under high pressure were developed. These techniques aimed to maximize compound recovery while minimizing environmental harm.Overall, the study provides a modern, efficient approach to analyzing and extracting valuable compounds from Georgian endemic plants while prioritizing environmental sustainability.

Dear Editor, Sugimoto and colleagues conducted a follow-up study of 28 postmenopausal women with osteoporosis to clarify the effect of once-weekly teriparatide administration for 24 weeks using several biologic markers [1]. After 24 weeks of treatment, significant increase of the serum osteocalcin, a bone formation marker, and significant decrease of the urinary deoxypiridinoline, a bone resorption marker, were observed. In contrast, no significant change of the serum procollagen type I N-terminal propeptide (PINP), a bone formation marker, or urinary cross-linked N-telopeptide of type I collagen (NTX), a bone resorption marker, was observed. I have two concerns on their study. First, the authors conducted their study without setting a standard protocol for the daily teriparatide administration, which is described in the last paragraph of the Discussion section as a study limitation. They measured four biological markers at four time-points, including measurements before the start of treatment. Unfortunately, there are differences in the test situations in the past several studies, which makes the comparability not satisfactory. For example, the authors have quoted two references [2, 3] related to the effects of two treatment regimens on fracture risk reduction, and I have a question as to their reason for arriving at the conclusion of no difference in the relative risk reduction between 80 and 65 % in these studies. There is no way to adjust for ethnic differences in the study, and comparison of data within the study should be conducted. In addition, the characteristics of their population should be checked for its representativeness of Japanese postmenopausal women. Second, distributions of PINP and NTX are logarithmicnormal in general, and Wilcoxon’s matched–pair signed–rank test should be applied if Friedman’s test with a strict criteria of alpha/3 shows significance. Alternatively, paired t test with logarithmic transformation of variables should be conducted after repeated-measure analysis of variance. The number of patients in the study is limited (n=28), and power analysis is indispensable for repeated measures [4]. Finally, the authors have mentioned in the last paragraph the advantage of sustainment for up to 72 weeks in their trial. But I feel that there is no clear evidence for their proposal. The lack of statistical significance does not mean the lack of clinical effectiveness, and setting of a control group as standard protocol should be considered for accurate analysis.

Purpose: Bioluminescence tomography(BLT) enhances commonly used 2D bioluminescence imaging by reconstructing 3D distributions of bioluminescence activity, allowing in vivo tumor localization. However, traditional physics model-based BLT struggles with model uncertainties and ill-posedness, limiting its ability to provide quantitative information, such as tumor volume. To address this, we introduce the Multiple-channel Hybrid Neural Network(McHyNN), a machine learning(ML) framework integrating light propagation model, multimodal imaging, and cross-animal data. We demonstrate McHyNN’s ability to accurately identify tumors and quantify their volumes, particularly in cases of small and multiple brain metastases(BM), making it highly valuable for cancer research. Method: McHyNN is a feed-forward neural network(NN) grounded in a light propagation model based on the diffusion equation. It incorporates multi-data channels, including multi-animal and multimodal data. For a given animal set, the data includes BL images emitted from internal tumors and corresponding MRI scan, if tumor is MRI-detectable. The NN outputs n+1 BL tumor distributions, including the n existing animal sets and the new subject, whose tumor information is to be determined. McHyNN leverages mutual information from light propagation across multiple animals and multimodal images, and the NN is optimized accordingly using loss function L = Ldiff + Limage. Ldiff and Limage minimize the difference between calculated and actual BL tumor distributions based on surface BLI measurement, and MRI data, respectively. We will first present numerical results based on simulated brain metastases in mice with experimentally determined noise, followed by showing the capability of BLT to reconstruct in vivo BMs in SCLC spontaneous animal model. Results: McHyNN accurately quantifies three small BMs (1.2 to 1.9 mm in length, volume: 0.9 to 1.9 mm3) within simulated mouse brain at localization accuracy of < 0.5mm and volume errors within 0.8 mm3, even when the tumors are separated by only 2-2.7 mm. In contrast, the compressive sensing algorithm commonly used in conventional BLT fails to distinguish these tumors. Moreover, we simulated single brain metastasis ranging from 1.0-3.6 mm in length, 0.4-17.2 mm3 including 10 tumors 1.5<mm or="" 1.75="" mm3. McHyNN successfully localized all cases within 0.5 mm and faithfully reconstructed tumor volumes, showing a linear correlation with ground truth (R2=0.99). The in vivo BMs study is ongoing. <mm or="" 1.75="" mm <mm or="" 1.75="" mm. Conclusions: Our BLT platform incorporating the McHyNN approach has potential to transform qualitative bioluminescence imaging into a 3D quantitative modality, particularly for tumor volume quantification and detecting small malignancies. This innovation will significantly enhance investigators’ capabilities in cancer studies. Citation Format: Beichuan Deng, Zhishen Tong, Yi-chun Tsai, James Kim, Hamid Dehghani, Ken Kang-Hsin Wang. Multiple-channel hybrid neural network to achieve quantitative bioluminescence tomography for cancer research [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 1301.