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Abstract Objective Stereotactic electroencephalography (SEEG) has been widely used to explore the epileptic network and localize the epileptic zone in patients with medically intractable epilepsy. Accurate anatomical labeling of SEEG electrode contacts is critically important for correctly interpreting epileptic activity. We present a method for automatically assigning anatomical labels to SEEG electrode contacts using a 3D‐segmented cortex and coregistered postoperative CT images. Method Stereotactic electroencephalography electrode contacts were spatially localized relative to the brain volume using a standard clinical procedure. Each contact was then assigned an anatomical label by clinical epilepsy fellows. Separately, each contact was automatically labeled by coregistering the subject's MRI to the USCBrain atlas using the BrainSuite software and assigning labels from the atlas based on contact locations. The results of both labeling methods were then compared, and a subsequent vetting of the anatomical labels was performed by expert review. Results Anatomical labeling agreement between the two methods for over 17 000 SEEG contacts was 82%. This agreement was consistent in patients with and without previous surgery (P = .852). Expert review of contacts in disagreement between the two methods resulted in agreement with the atlas based over manual labels in 48% of cases, agreement with manual over atlas‐based labels in 36% of cases, and disagreement with both methods in 16% of cases. Labels deemed incorrect by the expert review were then categorized as either in a region directly adjacent to the correct label or as a gross error, revealing a lower likelihood of gross error from the automated method. Significance The method for semi‐automated atlas‐based anatomical labeling we describe here demonstrates potential to assist clinical workflow by reducing both analysis time and the likelihood of gross anatomical error. Additionally, it provides a convenient means of intersubject analysis by standardizing the anatomical labels applied to SEEG contact locations across subjects.

Chronic anemia is commonly observed in patients with hemoglobinopathies, mainly represented by disorders of altered hemoglobin (Hb) structure (sickle cell disease, SCD) and impaired Hb synthesis (e.g. thalassemia syndromes, non-SCD anemia). Both hemoglobinopathies have been associated with white matter (WM) alterations. Novel structural MRI research in our laboratory demonstrated that WM volume was diffusely lower in deep, watershed areas proportional to anemia severity. Furthermore, diffusion tensor imaging analysis has provided evidence that WM microstructure is disrupted proportionally to Hb level and oxygen saturation. SCD patients have been widely studied and demonstrate lower fractional anisotropy (FA) in the corticospinal tract and cerebellum across the internal capsule and corpus callosum. In the present study, we compared 19 SCD and 15 non-SCD anemia patients with a wide range of Hb values allowing the characterization of the effects of chronic anemia in isolation of sickle Hb. We performed a tensor analysis to quantify FA changes in WM connectivity in chronic anemic patients. We calculated the volumetric mean of FA along the pathway of tracks connecting two regions of interest defined by BrainSuite's BCI-DNI atlas. In general, we found lower FA values in anemic patients; indicating the loss of coherence in the main diffusion direction that potentially indicates WM injury. We saw a positive correlation between FA and hemoglobin in these same regions, suggesting that decreased WM microstructural integrity FA is highly driven by chronic hypoxia. The only connection that did not follow this pattern was the connectivity within the left middle-inferior temporal gyrus. Interestingly, more reductions in FA were observed in non-SCD patients (mainly along with intrahemispheric WM bundles and watershed areas) than the SCD patients (mainly interhemispheric).

We describe a novel method for robust identification of common brain networks and their corresponding temporal dynamics across subjects from asynchronous functional MRI (fMRI) using tensor decomposition. We first temporally align asynchronous fMRI data using the orthogonal BrainSync transform, allowing us to study common brain networks across sessions and subjects. We then map the synchronized fMRI data into a 3D tensor (vertices × time × subject/session). Finally, we apply Nesterov-accelerated adaptive moment estimation (Nadam) within a scalable and robust sequential Canonical Polyadic (CP) decomposition framework to identify a low rank tensor approximation to the data. As a result of CP tensor decomposition, we successfully identified twelve known brain networks with their corresponding temporal dynamics from 40 subjects using the Human Connectome Project's language task fMRI data without any prior information regarding the specific task designs. Seven of these networks show distinct subjects’ responses to the language task with differing temporal dynamics; two show sub-components of the default mode network that exhibit deactivation during the tasks; the remaining three components reflect non-task-related activities. We compare results to those found using group independent component analysis (ICA) and canonical ICA. Bootstrap analysis demonstrates increased robustness of networks found using the CP tensor approach relative to ICA-based methods.

Sickle cell disease (SCD) is a life-threatening genetic condition. Patients suffer from chronic systemic and cerebral vascular disease that leads to early and cumulative neurological damage. Few studies have quantified the effects of this disease on brain morphometry and even fewer efforts have been devoted to older patients despite the progressive nature of the disease. This study quantifies global and regional brain volumes in adolescent and young adult patients with SCD and racially matched controls with the aim of distinguishing between age related changes associated with normal brain maturation and damage from sickle cell disease.T1 weighted images were acquired on 33 clinically asymptomatic SCD patients (age=21.3±7.8; F=18, M=15) and 32 racially matched control subjects (age=24.4±7.5; F=22, M=10). Exclusion criteria included pregnancy, previous overt stroke, acute chest, or pain crisis hospitalization within one month. All brain volume comparisons were corrected for age and sex.Globally, grey matter volume was not different but white matter volume was 8.1% lower (p=0.0056) in the right hemisphere and 6.8% (p=0.0068) in the left hemisphere in SCD patients compared with controls. Multivariate analysis retained hemoglobin (β=0.33; p=0.0036), sex (β=0.35; p=0.0017) and mean platelet volume (β=0.27; p=0.016) as significant factors in the final prediction model for white matter volume for a combined r2 of 0.37 (p

Abstract Background Follow-up assessment of visceral leishmaniasis (VL) treated cases is important to monitor the long term effectiveness of treatment regimens. The main objective of this study was to identify the gaps and challenges in the follow-up of treated VL cases, to monitor treatment outcome and to assess the impact of COVID-19 on VL elimination services and activities. Methods Clinicians treating VL patients, district focal persons for VL, and patients treated for VL in seven high endemic districts in Nepal during 2019–2022 were interviewed to collect data on challenges in the follow-up of VL treated patients as per national strategy. Results Follow up status was poor in two districts with the largest number of reported cases. The majority of cases were children under 10 years of age (44.2%). Among 104 VL treated cases interviewed, 60.6% mentioned that clinicians had called them for follow-up but only 37.5% had complied. Among 112 VL treated cases followed up, 8 (7.14%) had relapse and 2 (1.8%) had PKDL. Among 66 cases who had VL during the COVID-19 lock down period, 32 (48.5%) were diagnosed within 1 week; however, 10 (15.1%) were diagnosed only after 4 weeks or more. During the COVID-19 pandemic, there was no active search for VL because of budget constraints and lack of diagnostic tests, and no insecticide spraying was done. Conclusion Relapses and PKDL are challenges for VL elimination and a matter of concern. Successful implementation of the national strategy for follow up of treated VL cases requires addressing elements related to patients (awareness, transport, communication) clinicians (compliance) and organization of service delivery (local health worker training and deployment). COVID-19 did not have much impact on VL diagnosis and treatment; however, public health programmes including active case detection and insecticide spraying for vector control were severely reduced.

This article discusses the significance of knee joint mechanics and the consequences of knee dysfunctions on an individual's quality of life. The utilization of active knee braces, which incorporate concepts of mechatronics systems, is investigated here as a potential treatment option. The complexity of the construction of the knee joint, which has six degrees of motion and is more prone to injury since it bears weight, is emphasized in this article. By wearing braces and using other support devices, one's knee can increase stability and mobility. In addition, the paper discusses various technologies that can be used to measure the knee adduction moment and supply spatial information on gait. Actuators for active knee braces must be compact, lightweight, and capable of producing a significant amount of torque; as a result, electric, hydraulic, and pneumatic actuators are the most common types. Creating control mechanisms, such as position control techniques and force/torque control approaches, is essential to knee exoskeleton research and development. These methods might make knee joint rehabilitation and assistive technology safer and more effective.

Background & objectives: The successful elimination program of visceral leishmaniasis (VL) in Nepal decreased the incidence to less than 1 per 10,000 population leading to the consolidation phase. However, new VL cases have been recorded from new districts, threatening the elimination goal. This study monitors the geographical spread of VL and identifies potential risk factors. Methods: VL data of 2017–2020 were obtained from the Epidemiology and Disease Control Division (EDCD) of Nepal and mapped. Telephonic interviews with 13 VL patients were conducted. Results: The incidence maps indicate that VL is spreading to new areas. The target incidence exceeded four times in hilly and twice in mountainous districts. VL cases occurred in 64 of 77 districts in all three regions (mountainous, hilly and Terai). Interviews showed a correlation between travel history (private, commercial and for studies) and the spread of VL cases to new foci. Interpretation & conclusion: One major challenge of VL elimination in the maintenance phase is the spread of infection through travelers to new foci areas, which needs to be under continuous surveillance accompanied by vector control activities. This should be confirmed by a large-scale analytical study.

Nepal, Bangladesh, and India signed a Memorandum of Understanding (MoU) in 2005 to eliminate visceral leishmaniasis (VL) as a public health problem from the Indian subcontinent by 2015. By 2021, the number of reported VL cases in these countries had declined by over 95% compared to 2007. This dramatic success was achieved through an elimination programme that implemented early case detection and effective treatment, vector control, disease surveillance, community participation, and operational research that underpinned these strategies. The experience offered an opportunity to assess the contribution of implementation research (IR) to VL elimination in Nepal. Desk review and a stakeholder workshop was conducted to analyse the relationship between key research outputs, major strategic decisions in the national VL elimination programme, and annual number of reported new cases over time between 2005 and 2023. The results indicated that the key decisions across the strategic elements, throughout the course of the elimination programme (such as on the most appropriate tools for diganostics and treatment, and on best strategies for case finding and vector management), were IR informed. IR itself responded dynamically to changes that resulted from interventions, addressing new questions that emerged from the field. Close collaboration between researchers, programme managers, and implementers in priority setting, design, conduct, and review of studies facilitated uptake of evidence into policy and programmatic activities. VL case numbers in Nepal are now reduced by 90% compared to 2005. Although direct attribution of disease decline to research outputs is difficult to establish, the Nepal experience demonstrates that IR can be a critical enabler for disease elimination. The lessons can potentially inform IR strategies in other countries with diseases targeted for elimination.

Introduction: Iodine deficiency disorders are common endocrinopathies in Nepal. Children are at risk for iodine deficiency disorders. Irreversible mental retardation and brain damage in children are the devastating disorders lead by iodine deficiency. Therefore, the main objective of the study was to find out the prevalence of insufficient iodine level among the children of a secondary school. Methods: This descriptive cross-sectional study was conducted in urine from April 2019 to July 2019 after obtaining ethical approval from Nepal Health Research Council (Registration number: 802/2018). Forty-six urine samples were collected from school children for iodine estimation. Convenience sampling was done. Data were entered into Statistical Package for the Social Science version 21 and descriptive analyses were done. Point estimate at 95% confidence interval was calculated along with frequency and proportion for binary data. Results: Among the 46 students, majority 36 (78.30%) (95% Confidence Interval= 66.30-90.21) of the school children had insufficient urine iodine level. Among 36 salt samples collected from school children with low urine iodine level, 8 (22.2%) salt samples had iodine less than 15ppm. Conclusions: Iodine estimation revealed a very high percentage of urine samples containing insufficient levels of iodine is similar as compared to studies done in similar settings. Hence, the school children were at risk of iodine deficiency disorders. Iodine deficiency disorders prevention programs should be priority intervention based on available evidence.