Utricular dysfunction in patients with orthostatic hypotension.

PURPOSE: To delineate the association between otolithic dysfunction and orthostatic hypotension (OH). METHODS: We retrospectively reviewed the medical records of 382 patients who presented with orthostatic dizziness at a tertiary dizziness center between July 2017 and December 2021. Patients were included for analyses when they had completed ocular (oVEMP) and/or cervical vestibular-evoked myogenic potentials (cVEMP), and head-up tilt table test with a Finometer (n = 155). We compared the results between the patients with OH (n = 38) and those with NOI (normal head-up tilt table test despite orthostatic intolerance, n = 117). RESULTS: Thirty-eight patients with OH were further categorized as either classic (n = 30), delayed (n = 7), or initial (n = 1) types. Multivariable logistic regression showed that OH was associated with high baseline systolic BP (p = 0.046), presence of heart failure (p = 0.016), and unilateral oVEMP abnormalities (p = 0.016). n1 latency of oVEMP were negatively correlated with the maximal changes of systolic blood pressure (BP) in 15 s ([Formula: see text]SBP15s, p = 0.013), 3 min ([Formula: see text]SBP3min, p = 0.005) and 10 min ([Formula: see text]SBP10min, p = 0.002). In contrast, the n1-p1 amplitude was positively correlated with [Formula: see text]SBP15s (p = 0.029). Meanwhile, p13 latency of cVEMP was negatively correlated with [Formula: see text]SBP10min (p = 0.018). CONCLUSIONS: Our study provides evidence of utricular dysfunction related to OH.

Differentiating amnestic from non-amnestic mild cognitive impairment subtypes using graph theoretical measures of electroencephalography.

The purpose of this study was to explore different patterns of functional networks between amnestic mild cognitive impairment (aMCI) and non-aMCI (naMCI) using electroencephalography (EEG) graph theoretical analysis. The data of 197 drug-naïve individuals who complained cognitive impairment were reviewed. Resting-state EEG data was acquired. Graph analyses were performed and compared between aMCI and naMCI, as well as between early and late aMCI. Correlation analyses were conducted between the graph measures and neuropsychological test results. Machine learning algorithms were applied to determine whether the EEG graph measures could be used to distinguish aMCI from naMCI. Compared to naMCI, aMCI showed higher modularity in the beta band and lower radius in the gamma band. Modularity was negatively correlated with scores on the semantic fluency test, and the radius in the gamma band was positively correlated with visual memory, phonemic, and semantic fluency tests. The naïve Bayes algorithm classified aMCI and naMCI with 89% accuracy. Late aMCI showed inefficient and segregated network properties compared to early aMCI. Graph measures could differentiate aMCI from naMCI, suggesting that these measures might be considered as predictive markers for progression to Alzheimer's dementia in patients with MCI.

Head-impulse tests aid in differentiation of multiple system atrophy from Parkinson's disease.

The integrity of the vestibulo-ocular reflex (VOR) remains to be delineated in patients with parkinsonism. We aimed to define the findings of the VOR using head-impulse tests (HITs) and their differential diagnostic value in patients with Parkinson's disease (PD) and multiple system atrophy (MSA). From December 2019 to January 2021, 30 patients with PD and 23 patients with MSA (17 with cerebellar-type MSA and 6 with parkinsonian-type MSA) had a video-oculographic recording of HITs at two university hospitals in South Korea. Reversed (p = 0.034) and perverted (p = 0.015) catch-up saccades were more frequently observed in MSA than in PD during HITs. The gain difference between the ACs and the PCs were larger in MSA than in PD (p = 0.031), and positively correlated with the disease duration in patients with MSA (Spearman's coefficient = 0.512, p = 0.012). Multivariate logistic regression analysis showed that reversed (p = 0.044) and perverted (p = 0.039) catch-up saccades were more frequently associated with MSA than with PD during HITs. In conclusion, HITs aid in differentiation of MSA from PD, and may serve as a surrogate marker for the clinical decline.

Automated Classification of Normal Control and Early-Stage Dementia Based on Activities of Daily Living (ADL) Data Acquired from Smart Home Environment.

With the global trend toward an aging population, the increasing number of dementia patients and elderly living alone has emerged as a serious social issue in South Korea. The assessment of activities of daily living (ADL) is essential for diagnosing dementia. However, since the assessment is based on the ADL questionnaire, it relies on subjective judgment and lacks objectivity. Seven healthy seniors and six with early-stage dementia participated in the study to obtain ADL data. The derived ADL features were generated by smart home sensors. Statistical methods and machine learning techniques were employed to develop a model for auto-classifying the normal controls and early-stage dementia patients. The proposed approach verified the developed model as an objective ADL evaluation tool for the diagnosis of dementia. A random forest algorithm was used to compare a personalized model and a non-personalized model. The comparison result verified that the accuracy (91.20%) of the personalized model was higher than that (84.54%) of the non-personalized model. This indicates that the cognitive ability-based personalization showed encouraging performance in the classification of normal control and early-stage dementia and it is expected that the findings of this study will serve as important basic data for the objective diagnosis of dementia.

Drinking coffee enhances neurocognitive function by reorganizing brain functional connectivity.

The purpose of this study was to identify the mechanisms underlying effects of coffee on cognition in the context of brain networks. Here we investigated functional connectivity before and after drinking coffee using graph-theoretic analysis of electroencephalography (EEG). Twenty-one healthy adults voluntarily participated in this study. The resting-state EEG data and results of neuropsychological tests were consecutively acquired before and 30 min after coffee consumption. Graph analyses were performed and compared before and after coffee consumption. Correlation analyses were conducted to assess the relationship between changes in graph measures and those in cognitive function tests. Functional connectivity (FC) was reorganized toward more efficient network properties after coffee consumption. Performance in Digit Span tests and Trail Making Test Part B improved after coffee consumption, and the improved performance in executive function was correlated with changes in graph measures, reflecting a shift toward efficient network properties. The beneficial effects of coffee on cognitive function might be attributed to the reorganization of FC toward more efficient network properties. Based on our findings, the patterns of network reorganization could be used as quantitative markers to elucidate the mechanisms underlying the beneficial effects of coffee on cognition, especially executive function.

A Method of Radial Nerve Length Measurement Based on Cadaveric Investigation.

OBJECTIVE: To determine the most reliable method to measure the length of the radial nerve during a nerve conduction study (NCS). DESIGN: Cadaveric investigation. SETTING: A practical anatomy research laboratory in a university. PARTICIPANTS: Fresh cadavers (N=10), with 1 cadaver for study design and 9 for data. INTERVENTIONS: Design of measurement methods using cadaver dissection and comparison of the measured values to the true length in 18 arms of 9 cadavers. MAIN OUTCOME MEASURES: Four points (A, B, C, D) were determined: (A) proximal stimulation point in NCS; (B) point at the elbow crease; (C) point in the midforearm; and (D) distal stimulation point 5cm above the extensor indicis. The true length of the radial nerve between the stimulus points (points A and D) in NCS was compared with the measured values by summation of the straight line segments between those points with various combinations. The difference in root mean square error (RMSE) of the distance measured by each method compared with the true length was calculated to determine the best measurement method. RESULTS: The closest distance to the true length (28.7±2.8cm) in the cadaveric investigation was obtained using the summation of straight line segments between points A, B, and D (A-B-D, RMSE=.72cm), followed by the A-B-C-D distance (RMSE=.87cm) and the A-D distance (RMSE=1.38cm) methods, in sequence. The former 2 distance measurements were relatively closer to the true length than the latter measurement method. CONCLUSIONS: Multiple segmentation measurement methods reflected the course of the radial nerve better than a single linear measurement method. We suggest that the distance measured using a stopover point near the lateral epicondyle between 2 stimulus points (A-B-D distance) is closer to the true length of the nerve.

Takotsubo-Like Myocardial Dysfunction in Ischemic Stroke: A Hospital-Based Registry and Systematic Literature Review.

BACKGROUND AND PURPOSE: We investigated clinical and radiological characteristics of ischemic stroke patients with Takotsubo-like myocardial dysfunction. METHODS: From multicenter stroke registry database, ischemic stroke patients who underwent transthoracic echocardiography were found. Among these, patients were classified if they had specific ventricular regional wall motion abnormalities discording with coronary artery distribution, such as apical (typical pattern) or nonapical ballooning (atypical pattern), considered as echocardiographic findings of Takotsubo cardiomyopathy. Patients with ischemic heart disease history, myocarditis, or pheochromocytoma were excluded. We compared patients with Takotsubo-like myocardial dysfunction with those without and further performed systematic literature review on those with Takotsubo cardiomyopathy. RESULTS: This study included 23 patients (0.42%). The mean age was 70.7±13.9 years, with predominance of women (73.9%) and typical pattern of Takotsubo-like myocardial dysfunction (91.3%). They were associated with short-term poor functional outcomes, including high mortality, neurological deterioration, and functional status at discharge, compared with those without (39.1% versus 2.4%, 47.8% versus 7.4%; and median [interquartile range], 5 [5-6] versus 3 [2-4]; all P<0.001). They had a higher inflammatory marker level and lower triglyceride level. Ischemic lesions were more commonly found in the right anterior circulation with specific dominant regions being the insula and peri-insular areas. In addition, a trend toward a remarkable mortality rate and higher prevalence of insular involvement was observed in the propensity-score matching, subgroup fulfilling the strict Takotsubo cardiomyopath criteria, and was as reported in literature review. CONCLUSION: Stroke patients with Takotsubo-like myocardial dysfunction may differ from those without in clinical outcomes, laboratory findings, and radiological features.

Headache characteristics of uncomplicated intracranial vertebral artery dissection and validation of ICHD-3 beta diagnostic criteria for headache attributed to intracranial artery dissection.

BACKGROUND AND PURPOSE: Headache may be a warning sign of subsequent stroke in patients with vertebral artery dissection (VAD). Even though the headache characteristics of VAD have been described predominantly in patients with extracranial VAD and neurological complications, headache semiology is not well known in patients with uncomplicated intracranial vertebral artery dissection (ICVAD). In the present study, we attempt to identify the headache semiology that characterizes ICVAD and validate the revised version of the International Classification of Headache Disorders (ICHD-3 beta) criteria for headache attributed to intracranial artery dissection. METHODS: Six patients with neurologically uncomplicated ICVAD presented at a participating medical center, and eight similar patients were reviewed in the literature. Combining these data, we analyzed headache characteristics of patients with uncomplicated ICVAD according to their pain onset and duration, nature, intensity, location, aggravating and relieving factors, associated symptoms, response to medication, and prognosis. RESULTS: Headache in uncomplicated ICVAD usually has an acute mode of onset (11/14) and persistent (10/14) temporal feature. Pain that has a throbbing quality (nine of 14) and severe intensity (13/14) on the ipsilesional (10/14) and occipitonuchal area (12/14) is a headache prototype in ICVAD. Additionally, headache was intensified by head flexion and rotation (three of six), and relieved by head extension and supine positioning (five of six). Headache of all patients in the present study fulfilled the ICHD-3 beta criteria. CONCLUSION: Headache semiology of uncomplicated ICVAD is mostly homogenous in the present study. These characteristics may be helpful in the diagnosis of uncomplicated ICVAD.