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Functional Near-Infrared Spectroscopy (fNIRS) holds transformative potential for research and clinical applications in neuroscience due to its non-invasive nature and adaptability to real-world settings. However, despite its promise, fNIRS signal quality is sensitive to individual differences in biophysical factors such as hair and skin characteristics, which can significantly impact the absorption and scattering of near-infrared light. If not properly addressed, these factors risk biasing fNIRS research by disproportionately affecting signal quality across diverse populations. Our results quantify the impact of various hair properties, skin pigmentation as well as head size, sex and age on signal quality, providing quantitative guidance for future hardware advances and methodological standards to help overcome these critical barriers to inclusivity in fNIRS studies. We provide actionable guidelines for fNIRS researchers, including a suggested metadata table and recommendations for cap and optode configurations, hair management techniques, and strategies to optimize data collection across varied participants. This research paves the way for the development of more inclusive fNIRS technologies, fostering broader applicability and improved interpretability of neuroimaging data in diverse populations.

Functional near-infrared spectroscopy (fNIRS) technology has been steadily advancing since the first measurements of human brain activity over 30 years ago. Initially, efforts were focused on increasing the channel count of fNIRS systems and then to moving from sparse to high density arrays of sources and detectors, enhancing spatial resolution through overlapping measurements. Over the last ten years, there have been rapid developments in wearable fNIRS systems that place the light sources and detectors on the head as opposed to the original approach of using fiber optics to deliver the light between the hardware and the head. The miniaturization of the electronics and increased computational power continues to permit impressive advances in wearable fNIRS systems. Here we detail our design for a wearable fNIRS system that covers the whole head of an adult human with a high-density array of 56 sources and up to 192 detectors. We provide characterization of the system showing that its performance is among the best in published systems. Additionally, we provide demonstrative images of brain activation during a ball squeezing task. We have released the hardware design to the public, with the hope that the community will build upon our foundational work and drive further advancements., Competing Interests: AvL is currently consulting for NIRx Medizintechnik GmbH. The authors declare no other conflicts of interest., (© 2024 Optica Publishing Group.)

Accurate sensor placement is vital for non-invasive brain imaging, particularly for functional near-infrared spectroscopy (fNIRS) and diffuse optical tomography (DOT), which lack standardized layouts such as those in electroencephalography (EEG). Custom, manually prepared probe layouts on textile caps are often imprecise and labor intensive. We introduce a method for creating personalized, 3D-printed headgear, enabling the accurate translation of 3D brain coordinates to 2D printable panels for custom fNIRS and EEG sensor layouts while reducing costs and manual labor. Our approach uses atlas-based or subject-specific head models and a spring-relaxation algorithm for flattening 3D coordinates onto 2D panels, using 10-5 EEG coordinates for reference. This process ensures geometrical fidelity, crucial for accurate probe placement. Probe geometries and holder types are customizable and printed directly on the cap, making the approach agnostic to instrument manufacturers and probe types. Our ninjaCap method offers 2.7 ± 1.8    mm probe placement accuracy. Over the last five years, we have developed and validated this approach with over 50 cap models and 500 participants. A cloud-based ninjaCap generation pipeline along with detailed instructions is now available at openfnirs.org. The ninjaCap marks a significant advancement in creating individualized neuroimaging caps, reducing costs and labor while improving probe placement accuracy, thereby reducing variability in research., (© 2024 The Authors.)

Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision.

Background: Third window syndrome is a vestibular-cochlear disorder in humans in which a third mobile window of the otic capsule creates changes to the flow of sound pressure energy through the perilymph/endolymph. The nature and location of this third mobile window can occur at many different sites (or multiple sites); however, the most common third mobile window is superior semicircular canal dehiscence (SSCD). There are two essential objective diagnostic characteristics needed to validate a model of SSCD: the creation of a pseudoconductive hearing loss and cVEMP increased amplitude and decreased threshold., Methods: Adult Mongolian gerbils ( n = 36) received surgical fenestration of the superior semicircular canal of the left inner ear. ABR and c+VEMP testing were carried out prior to surgery and over acute (small 1 mm SSCD, 1-10 days) or prolonged (large 2 mm SSCD, 28 days) recovery. Because recovery of function occurred quickly, condenser brightfield stereomicroscopic examination of the dehiscence site was carried out for the small SSCD animals post-hoc and compared to both ABRs and c+VEMPs. Micro-CT analysis was also completed with representative samples of control, day 3 and 10 post-SSCD animals., Results: The SSCD created a significant worsening of hearing thresholds of the left ear; especially in the lower frequency domain (1-4 kHz). Left (EXP)/right (CTL) ear comparisons via ABR show significant worsening thresholds at the same frequency representations, which is a proxy for the human pseudoconductive hearing loss seen in SSCD. For the c+VEMP measurements, increased amplitude of the sound-induced response (N1 2.5 ms and P1 3.2 ms) was observed in animals that received larger fenestrations. As the bone regrew, the c+VEMP and ABR responses returned toward preoperative values. For small SSCD animals, micro-CT data show that progressive osteoneogenesis results in resurfacing of the SSCD without bony obliteration., Conclusion: The large (2 mm) SSCD used in our gerbil model results in similar electrophysiologic findings observed in patients with SSCD. The changes observed also reverse and return to baseline as the SSCD heals by bone resurfacing (with the lumen intact). Hence, this model does not require a second surgical procedure to plug the SSCD., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wackym, Balaban, Van Osch, Morris, Tamakloe, Salvatore, Duwadi, Gay and Mowery.)

The socio-cultural context of populations has a significant effect on health outcomes across every stage of life. In Australia, South Asian migrants have a comparatively higher incidence of chronic disease and less use of health services. Often overlooked are community views of health, cultural traits and belief systems. This study aimed to explore the factors that influence health perception and practice of South Asian migrants. The study used a mixed method approach with both a survey and interviews. A total of 62 participants between the age of 18 and 64 years were surveyed and 14 participants completed interviews. Data were analysed descriptively and thematically. South Asians share a common perception and practice around health and illness. This paper highlights two key findings. First, these groups take a broad view of health encompassing physical, mental, emotional, social and economic aspects of life. Second, these cultural groups do not seek medical help as their first choice, but have a high level of trust in family for providing health advice and share a belief in the effectiveness of home remedies for managing health conditions. Participants shared their expectation that the Australian health system should consider their socio-cultural construct to make services culturally safe and engaging to enhance service utilisation.

Background: Migrants settling in a new country experience multiple complexities in navigating health care systems and adapting to a new way of life in the host country. In South Asia, migrating to another country for better life opportunities has been an ongoing trend and migration to Australia has significantly increased in recent years. Lower utilisation of health services and higher risks of chronic diseases among South Asian migrants poses a continuing challenge for the Australian health care system and little is known about why this demographic group does not access health services at the same rate. This study aimed to explore factors influencing access to health care by South Asian migrants in Australia., Methods: Using a mixed-method design, we conducted 62 online survey and 14 in-depth interviews with participants from four South Asian countries: Nepal, India, Bhutan, and Sri Lanka. Participants were recruited using a purposive snowball sampling approach following a standard ethical approval process. Survey data were analysed descriptively in SPSS and interview data were recorded, transcribed, and analysed thematically., Results: South Asian migrants experienced various complexities while accessing health services in Australia. The findings of this study highlighted a number of negative factors influencing their experiences of accessing health care: long waiting times for public health care, the expense of private health care, and communication problems due to socio-cultural differences. South Asian migrants also expressed their concern for a greater investment of resources into public health care to enable them to access quality and affordable care in these settings., Conclusions: Given limited evidence available to help understand factors leading to the lower utilisation of health care and higher risks of chronic diseases among South Asian migrants, this study plays an important role in highlighting social, cultural, financial, and institutional factors that are critical to designing appropriate health-care strategies. This study recommends incorporating a collaborative and culturally competent model of care to increase access to health care and thereby help reduce existing disparities in health outcomes among South Asian migrant populations., (© 2021. The Author(s).)

Introduction: Perinatal mortality comprises the number of stillbirths and death of newborns within seven days of life which is the main contributor to infant and maternal mortality. The aim of this study was to find out the prevalence of perinatal mortality among all the deliveries in a tertiary care center of a remote part of Nepal., Methods: This was a descriptive cross-sectional study conducted in a tertiary care center located in Jumla among 3798 deliveries (childbirth) from August 2014 to April 2020. Ethical approval was taken from the institutional review committee (2076/2077/05) of the same institution. A convenience sampling technique was used and the data were collected from the medical record section and then entered and analyzed in Statistical Package for Social Sciences version 16. Point estimate at 95% Confidence Interval was calculated along with frequencies and percentages for binary data., Results: The prevalence of perinatal mortality was 187 (4.92%) (4.23-4.60% at 95% Confidence Interval) among 3798 deliveries. Regarding the primary causes; the highest proportion was intrapartum hypoxia 62 (33.3%), spontaneous preterm labor 40 (21.5%), and congenital anomalies 38 (20.4%). Similarly, about the final cause; the highest proportion was birth asphyxia 64 (34.2%), intrauterine fetal death 51 (27.3%), congenital anomalies 35 (18.7%), and complication of prematurity 32 (17.1%)., Conclusions: The perinatal mortality was quite high in this study with respect to similar studies done in other countries. The finding of this study showed that quality antenatal care with rural ultrasound service is essential to reduce the causes of perinatal mortality.

Peripherally inserted central catheter (PICC) is extensively used in critical care settings, because it plays a vital role in providing safe central venous entry. However, PICC is associated with several complications, which should be detected to shorten the duration of patients' improvement, reduce health care cost, and lessen the incidence of various PICC-related complications. Therefore, this study aimed to outline current literature on PICC procedures, potential complications, and measures for prevention. Understanding evidence-based guidelines regarding insertion technique, early detection of complications, and care bundle of PICC is significant in complication prevention. Implementation of education, training, and appropriate multidisciplinary approaches on PICC care among nurses and caregivers is the key to preventing complications. Thus, the strict care of indwelling PICC lines, the targeted and reasonable PICC-associated complication prevention, and nursing care have a major clinical significance in reducing the occurrence of potential PICC complications.