Clinical and Translational Neuroscience

Purpose: Accurate and precise navigation in space and postural stability rely on the central integration of multisensory input (vestibular, proprioceptive, visual), weighted according to its reliability, to continuously update the internal estimate of the direction of gravity. In this study, we examined both peripheral and central vestibular functions in a world-renowned 53-year-old male tightrope walker and investigated the extent to which his exceptional performance was reflected in our findings. Methods: Comprehensive assessments were conducted, including semicircular canal function tests (caloric irrigation, rotatory-chair testing, video head impulse testing of all six canals, dynamic visual acuity) and otolith function evaluations (subjective visual vertical, fundus photography, ocular/cervical vestibular-evoked myogenic potentials [oVEMPs/cVEMPs]). Additionally, static and dynamic posturography, as well as video-oculography (smooth-pursuit eye movements, saccades, nystagmus testing), were performed. The participant’s results were compared to established normative values. High-resolution diffusion tensor magnetic resonance imaging (DT-MRI) was utilized to assess motor tract integrity. Results: Semicircular canal testing revealed normal results except for a slightly reduced response to right-sided caloric irrigation (26% asymmetry ratio; cut-off = 25%). Otolith testing, however, showed marked asymmetry in oVEMP amplitudes, confirmed with two devices (37% and 53% weaker on the left side; cut-off = 30%). Bone-conducted cVEMP amplitudes were mildly reduced bilaterally. Posturography, video-oculography, and subjective visual vertical testing were all within normal ranges. Diffusion tensor MRI revealed no structural abnormalities correlating with the observed functional asymmetry. Conclusions: This professional tightrope walker’s exceptional balance skills contrast starkly with significant peripheral vestibular (otolithic) deficits, while MR imaging, including diffusion tensor imaging, remained normal. These findings highlight the critical role of central computational mechanisms in optimizing multisensory input signals and fully compensating for vestibular asymmetries in this unique case. Full article

Background: Dementia with Lewy bodies (DLBs) often presents with neuropsychiatric symptoms (NPSs), yet the role of hyperglycemia, a common cause of delirium in older adults, as a contributing factor remains under-recognized. This article aims to explore the relationship between hyperglycemia and NPSs. Methods: We report the case of a 71-year-old male with DLBs and type 2 diabetes mellitus (T2DM) who experienced worsening NPSs closely associated with periods of hyperglycemia. Initial pharmacological and nonpharmacological interventions were insufficient, prompting adjustments to insulin therapy and dietary modifications to stabilize blood glucose levels. Results: Improved glycemic control resulted in a clinically significant reduction in NPSs. Conclusions: This case suggests a potential link between hyperglycemia and NPSs in DLB patients, emphasizing the importance of maintaining glycemic control in managing NPSs. Although the exact mechanisms remain incompletely understood, adopting a holistic framework for brain health could offer a comprehensive approach to cognitive care. Further studies are needed to elucidate the biological pathways involved, validate these findings in larger populations, and develop evidence-based clinical guidelines. Full article

Posttraumatic stress disorder (PTSD) is a common neuropsychiatric condition with a complex etiology. Stellate Ganglion Block (SGB) is a novel but well-observed procedure for treating the disorder. However, the long-term durability of SGB has yet to be established. The primary objective of this study was to determine if performing ultrasound-guided, bilateral, two-level cervical sympathetic chain block (2LCSB) is associated with PTSD symptom improvement across six months. A secondary objective was to characterize treatment effects between trauma types. A retrospective chart review was conducted, and 75 patients meeting inclusion and exclusion criteria were identified. Posttraumatic stress disorder checklist for DSM-5 (PCL-5) scores were collected throughout a six-month period post-procedure. In addition, patients were asked to identify the category of trauma associated with their PTSD diagnosis. Nearly all (96%) patients showed significant improvement in their PCL-5 scores between the baseline and six months, with an average improvement of 55.48%. This is the first study to be conducted that examines the effects associated with SGB over a time period of greater than one month. Bilateral 2LCSB may provide durable PTSD symptom improvement for six months. However, additional research is necessary to establish causality. Full article

Background: Intracranial stenting is still feasible, but its effectiveness is still investigational. Our study investigated outcomes of endovascular treatment in high-volume and low-volume centres. Methods: We retrospectively recruited 36 patients with intracranial atherosclerosis who underwent endovascular treatment from January 2014 to June 2016 at three low-volume centres (n = 18), and a single high-volume centre (n = 18). Detailed periprocedural records, as well as clinical and radiological follow-up data, were revised through at least one-year post-procedure. The outcome parameters included successful revascularization, occurrence of any death, stroke, and/or Transient Ischaemic Attack (TIA) after intervention or during the follow-up period, and restenosis (≥50%). Results: The successful revascularization rate was 97.2%. The 30-day rate of any death, stroke, and/or TIA was 13.9%. At a median clinical follow-up of 18 months, the rate of any death, stroke, and/or TIA was 27.8%. Rates of any death, stroke, and/or TIA at 30 days and 18 months were higher among patients treated in low-volume centres versus those treated in high-volume centres but without reaching statistical significance (22.2% versus 5.6%, p = 0.188; and 38.9% versus 16.7%, p = 0.137, respectively). Conclusions: Although not statistically significant, our study showed a higher incidence of death, stroke and/or TIA among patients treated in the low-volume centre compared to those treated in the high-volume centre. Full article

(1) Background: Persistent post-COVID-19 headaches are emerging as a significant post-infection symptom. This study investigates the clinical characteristics of persistent post-COVID-19 headaches and the potential role of pro-inflammatory cytokines. (2) Methods: We conducted a pilot case–control study involving 84 participants divided into three groups: post-COVID with headache (n = 28), post-COVID without headache (n = 28), and healthy controls (n = 28). The detailed headache characteristics, including pain intensity, were assessed using the Visual Analog Scale (VAS). The serum levels of inflammatory cytokines (IL-6 and TNF-α) were measured. (3) Results: Post-COVID headaches predominantly presented as bilateral (53.6%) and throbbing (60.7%) in nature, with a median of 12 headache days per month and high pain intensity (median VAS score = 80). The associated symptoms were phonophobia (85.7%), fatigue (78.6%), and photophobia (75%). The serum levels of IL-6 and TNF-α were significantly higher in post-COVID headache patients than in the post-COVID without headache and healthy control groups (p < 0.001). A Receiver Operating Characteristic analysis showed that the circulating levels of IL-6 and TNF-α could discriminate our study groups at cutoffs with variable sensitivity and specificity. (4) Conclusions: Persistent post-COVID-19 headaches have diverse clinical characteristics and are associated with elevated circulating levels of pro-inflammatory cytokines, suggesting a potential underlying neuroinflammation. Full article

Intracerebral hemorrhage (ICH) is a significant health problem with high mortality and morbidity rates, partly due to limited treatment options. Hematoma after ICH causes neurological deficits due to the mass effect. Hemorrhage catalyzes secondary damage, resulting in increased neurological damage, poor prognosis, and treatment problems. This review evaluates the role of immunotherapeutic approaches in ICH based on original full-text and review articles on the pathophysiology and immunotherapy of ICH, with emphasis on the modulation of microglia/macrophage polarization to the M2 subtype. In this review, we concluded that the pathophysiology of injury progression after ICH is complex and multifaceted. Inflammation plays a dominant role in secondary injuries. Furthermore, cells involved in the inflammatory process have dual roles in pro-inflammatory/destructive and anti-inflammatory/healing. While the role of inflammation in the pathophysiology makes the immune system a therapeutic target in ICH, the dual role of cells makes them a therapeutic target that can modulate anti-inflammatory/healing. Resident microglia (and even macrophages migrating from a peripheral source) are important therapeutic targets for modulation because of their role in the initiation phase and in shaping immunity. Although clinical results remain poor, experimental and clinical trial data seem promising for deciphering the pathophysiology of ICH and providing treatment options. Full article

Introduction: Cortical spreading depression (CSD) is thought to be the pathophysiologic correlate of migraine aura. In experimental animals, CSD was shown to cause an increase in oxyhemoglobin. Susceptibility weighted imaging (SWI) on magnetic resonance imaging (MRI) depicts cerebral veins according to their concentration in oxyhemoglobin. The aim of this study was to assess whether the distribution of SWI changes in people with migraine aura resembles the clinical presentation, with a focus on topology. Methods: In this retrospective single-center study, patients were included if they (i) had acute focal neurological symptoms beginning with visual symptoms, (ii) underwent head MRI including SWI within eight hours of symptom onset, (iii) SWI showed focal dilated veins, and (iv) they had a discharge diagnosis of migraine with aura. Eleven predefined cerebral regions of interest (ROIs) were assessed for prominent focal veins (PFVs) on SWI. We determined whether symptoms correlated with the topography of ROIs with PFVs. Results: We found a posterior to anterior gradient of SWI changes during acute migraine aura when visual symptoms were present. Conclusion: MRI with SWI might be able to detect traces of CSD. The posterior to anterior distribution of areas with SWI changes corresponds anatomically to the canonical succession of symptoms in migraine aura. Full article

Background/Objectives: Brain tumors are among the severe and life-threatening conditions, with timely and accurate detection being crucial for determining the appropriate course of treatment. These tumors can vary widely in their aggressiveness, location, and type, making early diagnosis and precise classification essential for improving patient outcomes and survival rates. The complexity of brain tumors, combined with the detailed nature of MRI scans, presents significant challenges in the diagnostic process, underscoring the need for advanced tools to support clinicians in making informed decisions. New Method: This study focuses on developing and evaluating a proposed model for brain tumor classification using MRI images. The model employs a transfer learning approach fine-tuned to the brain tumor dataset, explicitly utilizing the EfficientNetB0 architecture. Results: The proposed model achieved an outstanding overall accuracy of 0.99, with precision, recall, and F1 scores exceeding 0.98 across all tumor classes. Comparison with Existing Methods: These results demonstrate the model’s potential as a reliable tool for assisting clinicians in diagnosing and classifying brain tumors. Conclusions: This is particularly valuable in the early stages of tumor development, where detection can be challenging, and early intervention is critical for successful treatment. Full article

Neuroradiology, as a modern branch of the neurosciences and radiological sciences, has an impact on global health, particularly on brain health. On the one hand, neuroradiology directly impacts diseases of the nervous system, such as stroke and inflammatory diseases, by providing an all-in-one package combining imaging, diagnosis, treatment, and follow-up. This has been impacted by the continuous evolution over the last decades of both diagnostic and interventional tools in parallel: this was the case in stroke, where the endovascular treatment was followed closely by developments in fast MRI techniques and multi-slice CT imaging. Additionally, inflammatory diseases of the brain, as well as tumors of the central nervous system, can be imaged and localized in order to set in place both an early diagnosis and initiate treatment. Neurodegenerative diseases such as Alzheimer’s disease, in which treatment options are appearing on the horizon, also benefit from the use of modern neuroimaging techniques. On the other hand, neuroradiology plays an important role in the prevention and prediction of brain diseases and helps in building up the so-called digital twin, often from birth till late in life. Additionally, the practice of neuroradiology itself is evolving to not only improve patient health but also the health of the practitioners of neuroradiology themselves. By improving the overall work environment also, neuroradiologists will be working under better conditions and will suffer less fatigue and burn-out, thereby providing better service to patients and population. By using less radiation for diagnostic tests and shifting to techniques that rely more and more on either magnetic resonance or ultra-sound techniques, the radiation load on the population and on the neuroradiologists will decrease. Furthermore, using less contrast, such as gadolinium, has been shown to result in fewer deposits in the brains of patients, as well as less pollution at the ocean level, thus contributing to general well-being. Additionally, the implementation and use of artificial intelligence at many levels of the diagnostic and treatment chain will be beneficial to patients and physicians. In this paper, we discuss the place and potential not just of the techniques but of neuroradiology and the neuroradiologist as promoters of brain health and thus global health. Full article

Background: Traumatic brain injury (TBI) is referred to as a “silent epidemic” due to its limited awareness in the general public. Nevertheless, it can cause chronic, lifelong physical and cognitive impairments with severe impact on quality of life, resulting in high healthcare costs and loss of employment. To evaluate the outcome after mild and moderate TBI, “return to work (RTW)” is a relevant parameter, reflecting the socio-economic consequences of TBI. Our study aims to summarize RTW-rates to raise awareness on the impact of non-severe TBI. Methods: We performed a systematic literature review screening the databases Medline, Embase and Web of Science for studies reporting RTW in mild to moderate TBI. Studies that reported on RTW after mild or moderate TBI (defined by GCS > 9) in adults, with a minimum follow-up of six months were included. Risk of bias was assessed using the QUIPS tool. Results: We included 13 studies with a total 22,550 patients. The overall RTW rate after at least six months, varies between 37% and 98%. Full RTW is reported in six of the included 13 studies and varies between 12% and 67%. In six studies (46%) the RTW-rate by the end of follow-up was ≤60%, with four studies being from high-income countries. Conclusion: Mild and moderate TBI have a high impact on employment rates with diverging rates for RTW even between high-income countries. Increasing the societal awareness of this silent epidemic is of utmost importance and is one of the missions of the Swiss Brain Health Plan. Full article

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) is a rare mitochondrial disorder primarily presenting in pediatric patients, with onset after 40 years being exceptionally rare (1–6%). Here, we report a complex diagnostic journey of a 47-year-old male presenting with new-onset seizures, hemiparesis, and neurocognitive deficits. Initial work-up, including MRI, CSF analysis, and extensive antibody screening, yielded inconclusive results, prompting differential considerations such as autoimmune encephalitis and neoplastic conditions. Finally muscle biopsy findings, coupled with genetic confirmation of the m.3243A>G mutation in the MT-TL1 gene, ultimately established the diagnosis of MELAS. This case depicts the atypical presentation of adult-onset MELAS without initial lactic acidemia, diabetes, or hearing impairment. The prolonged diagnostic process underscores the challenges of identifying rare diseases under today’s financial and administrative constraints. Still ee emphasize the importance of comprehensive diagnostics in rare cases to advance generall understanding and improve future patient outcomes, also amidst resource limitations. Full article

An intronic GAA repeat expansion in the FGF14 gene was recently identified as a common cause of autosomal dominant GAA-FGF14 ataxia (SCA27B). We aimed to characterize in detail the clinical and video-oculographic features in our cohort of SCA27B patients. We genotyped the FGF14 GAA repeat expansion in 52 patients with unsolved late-onset cerebellar ataxia. Brain MRI and nerve conduction study, as well as video-oculographic (VOG) assessment, were performed. Eight patients (15.4%) with pathogenic GAA repeat expansion in the FGF14 gene were found. The median age at onset was 51 years (range—23–63 years). Sensory axonal neuropathy was found in 5/8 patients. Cerebellar atrophy was observed in 5/8 patients, and in one case, pontocerebellar atrophy was found. All tested patients had impaired smooth pursuit, 5/6 patients had impaired vestibulo-ocular reflex suppression, nystagmus, and an increased number of square wave jerks, 4/6 patients had horizontal gaze-evoked nystagmus, 3/6 had spontaneous downbeat nystagmus, and 1/6 had an upbeat one. Video head impulse test gain was lower than 0.8 on both sides in 2/4 patients, along with the presence of overt saccades. Further studies in different cohorts are needed to complete the phenotype of the FGF14-related disorders. Full article

The Glasgow Coma Scale (GCS) is essential for assessing traumatic brain injury and predicting patient outcomes, yet studies indicate that nurses often have only a basic understanding of the GCS. In Saudi Arabia, research on this topic is limited, suggesting a need for improvement in nurses’ GCS knowledge. This study aimed to evaluate the knowledge and proficiency of 199 staff nurses at King Fahd Medical City in Riyadh, Saudi Arabia, regarding GCS usage and to identify the factors impacting their competence. A descriptive, cross-sectional survey was conducted, and the data were analyzed using SPSS version 23.0. The results showed that 81.4% of nurses had an average level of GCS knowledge, with a mean score of 8.8 ± 1.826. Only 13.6% demonstrated good knowledge, while 5% had poor knowledge. A significant correlation was found between GCS knowledge and nurses’ departments (χ2(2) = 19.184, p < 0.001). The study concludes that GCS knowledge among nurses in this Saudi Arabian center is moderate, highlighting the need for continuous education programs to enhance their competence in GCS assessment. Full article

Across many resting-state electroencephalography (EEG) studies, dementia is associated with changes to the power spectrum and fractal dimension. Here, we describe a novel method to examine changes in the fractal dimension over time and within frequency bands. This method, which we call fractal dimension distributions (FDD), combines spectral and complexity information. In this study, we illustrate this new method by applying it to resting-state EEG data recorded from patients with subjective cognitive impairment (SCI) or dementia. We compared the performance of FDD with the performance of standard fractal dimension metrics (Higuchi and Katz FD). FDD revealed larger group differences detectable at greater numbers of EEG recording sites. Moreover, linear models using FDD features had lower AIC and higher R² than models using standard full time-course measures of the fractal dimension. FDD metrics also outperformed the full time-course metrics when comparing SCI with a subset of dementia patients diagnosed with Alzheimer’s disease. FDD offers unique information beyond traditional full time-course fractal analyses and may help to identify dementia caused by Alzheimer’s disease and dementia from other causes. Full article

A large number of disease-modifying immunotherapies are available for the treatment of people with multiple sclerosis. Many disease-modifying immunotherapies show scarce or no safety data in pregnancy and breastfeeding and are labeled as being contraindicated during these periods in the Swiss summary of product characteristics. Some disease-modifying immunotherapies also have restrictions for male patients. Hence, family planning should always be considered in treatment decisions. If clinically necessary, the continuation of immunotherapy during pregnancy can be considered for some substances. In these situations, the “Good Off-Label Use Practice”, careful consideration of the benefit–risk profile, and interprofessional cooperation between the treating neurologist, obstetrician–gynecologist, and pharmacist/pharmacologist, ideally with the involvement of experienced centers, is necessary. Here, we present an update on disease-modifying immunotherapies in multiple sclerosis with a focus on family planning, pregnancy, and breastfeeding and provide consensus recommendations of the Medico-Scientific Advisory Board of the Swiss Multiple Sclerosis Society, the Swiss Neurological Society, and the Swiss Society for Gynecology and Obstetrics (represented by the Academy of Fetomaternal Medicine). These unified national recommendations are necessary, as guidelines from other countries differ and because of separate approval/reimbursement situations in Switzerland. Full article

Narcolepsy is a chronic central disorder of hypersomnolence most frequently arising during childhood/adolescence. This review article examined the literature concerning the etiology, prevalence, clinical course, and treatment of children with type 1 narcolepsy (NT1). Core symptoms of pediatric NT1 include excessive daytime sleepiness (EDS) and cataplexy, together with disrupted night sleep, sleep paralysis, and hypnagogic and hypnopompic hallucinations that can also occur. This disease frequently presents several comorbidities, such as obesity and precocious puberty, conditions ranging from psychological distress to psychiatric disorders, and cognitive aspects that further worsen the clinical picture. NT1 impairs the quality of life of children, thus calling for an early diagnosis and adequate treatment. To date, pharmacological treatments have been registered for childhood NT1 and can improve symptoms. Non-pharmacological approaches are also essential to improve patients’ well-being, ranging from behavioral treatments (e.g., planned napping) to psychosocial interventions (e.g., school programs). Multidisciplinary treatment management and early diagnosis are key factors in order to allow for adequate quality of life and development in children with NT1. Full article

Main Topic: Artificial Intelligence and Digitalization: Applications to Neurosurgery and Neuroradiology. On behalf of the SSNS and SSNR, we are pleased to present the Abstracts of the Joint Annual Meeting, which is held at the Congress Kursaal Interlaken, Switzerland, 20–21 June 2024. In total, 62 abstracts were selected, of which 19 abstracts are oral presentations and 43 abstracts are for ePoster. We congratulate all the presenters on their research work and contribution. Full article

Robust evidence suggests that the glymphatic system plays a key role in preserving brain health. Indeed, its activity in maintaining homeostasis by clearing neurotoxic proteins such as beta-amyloid from the human brain is essential. Sleep represents the factor that mainly influences this system, since it is selectively active during the night, in particular during non-rapid eye movement (NREM) sleep. This is true, since the sleep head position, in particular the supine position for its relationship to the status of opening/closing of the jugular veins, appears to be determinant for the development of future neurodegeneration. Growing evidence from human and animal models highlights the neurobiological link between sleep, glymphatic dysfunction and neurodegeneration. On the other hand, several modifiable factors have been recently identified modulating (improve/reduce) glymphatic system activity, such as Omega-3 polyunsaturated fatty acids, stress, hypertension, physical activity, alcohol, gender and genetic predisposition, in particular variants of aquaporin-4 (AQP4). From this viewpoint, our ambition is to discuss how the glymphatic system works in the brain, what factors mainly impact on this activity and its strict relation with the neurodegeneration. Future directions might include the analysis of factors modulating glymphatic system activity and a personalized glymphatic profile, “glymphatom”, as a natural target for preventive neurodegenerative treatment. Full article

On behalf of the SNS, we are pleased to present the Abstracts of the Annual Meeting which is held at the Congress Center in Basel, Switzerland, from 6–7 June 2024. In total, 83 abstracts were selected, whereof we include 8 abstracts for the Plenary Sessions, 6 abstracts for the SAYN GemSession, 30 abstracts for Poster flash presentations, and 39 abstracts as ePosters. We congratulate all the presenters on their research work and contributions. Full article