Left dominance of EEG abnormalities in patients with transient global amnesia

AbstractPurposeTransient global amnesia (TGA) is a syndrome of unknown etiology. Electroencephalographic (EEG) abnormalities in TGA have been reported previously. We analyzed the frequency and characteristics of EEG abnormalities in patients with TGA.MethodsWe collected EEGs of patients with a clinical diagnosis of TGA who had visited the emergency room or the outpatient clinic over a period of 8 years and compared clinical and demographic characteristics of the patients with normal EEGs with those with abnormal EEGs.ResultsEEG abnormalities were found in 35 (22.9%) out of 153 patients and epileptiform discharges were seen in 26 (74.3%) out of these 35 patients. Spikes or sharp waves were detected on the left side only (48.6%) or on both sides (25.7%), but none of the patients showed spikes or sharp waves on right side only. In six patients the EEG had normalized within three months of presentation, in ten within six months, and in twelve by one year. The EEG remained abnormal in eleven out of the 23 patients one year after presentation.ConclusionIn this largest consecutive EEG study at one center, the proportion of patients with TGA in whom epileptiform discharges were demonstrated within days of the episode of TGA was significantly higher than in the previous literature. EEG abnormalities such as spikes or sharp waves spontaneously disappeared in almost half of cases over one-year of follow-up. There was a clear left dominance of EEG abnormalities in patients with TGA

Cerebellar Hypoperfusion during Transient Global Amnesia: An MRI and Oculographic Study

Background and Purpose Transient global amnesia (TGA) is characterized by sudden anterograde and retrograde amnesia lasting for LIP to 24 hours. Diffusion-weighted magnetic resonance imaging (DWI) in cases of TGA and ischemia demonstrates a high frequency of high signal intensities restricted to the hippocampus, and this has been proposed as an etiology of TGA. The aims of this study were to characterize the DWI and single-photon-emission computed tomography (SPECT) findings during the acute and recovered phases of TGA and to correlate the findings with oculomotor abnormalities. Methods Five consecutive patients with a clinical diagnosis of TGA underwent DWI and SPECT of the brain within 24 hours after symptom onset and again 3 days later. Eye movements were also recorded using three-dimensional video-oculography. Results In all patients, DWI disclosed small punctuate (1-3 mm), high-signal lesions in the lateral portion of the hippocampus. The initial SPECT also revealed hypoperfusion in the cerebellar vermis, which had recovered by the follow-up examination. Three patients showed saccadic hypermetria or impaired smooth pursuit only during the acute phase. Conclusions Our patients with TGA showed cerebellar vermian hypoperfusion in addition to ischemic insults to the lateral hippocampus. The oculomotor abnormalities observed in our patients support the Occurrence of cerebellar dysfunction during the TGA attack. J Clin Neurol 2009;5:74-80This study was supported by a grant of the Korean Health 21 R&D Project, Ministry of Health and Welfare, Republic of Korea (no. A050079).Yang Y, 2008, J CLIN NEUROL, V4, P59Sander K, 2005, LANCET NEUROL, V4, P437Lampl Y, 2004, ACTA NEUROL SCAND, V110, P75Tong DC, 2004, NEUROLOGY, V62, P2154Takeuchi R, 2004, EUR J NUCL MED MOL I, V31, P578, DOI 10.1007/s00259-003-1406-8Teicher MH, 2003, NEUROSCI BIOBEHAV R, V27, P33, DOI 10.1016/S0149-7634(03)00007-1Anderson CM, 2002, PSYCHONEUROENDOCRINO, V27, P231Asada T, 2000, PSYCHIAT CLIN NEUROS, V54, P691Pantoni L, 2000, ACTA NEUROL SCAND, V102, P275Jovin TG, 2000, J NEUROIMAGING, V10, P238Warren JD, 2000, J CLIN NEUROSCI, V7, P57Levitt JJ, 1999, AM J PSYCHIAT, V156, P1105Loeber RT, 1999, SCHIZOPHR RES, V37, P81Giedd JN, 1999, PROG NEURO-PSYCHOPH, V23, P571SCHMAHMANN JD, 1999, MOVEMENT DISORDERSBerquin PC, 1998, NEUROLOGY, V50, P1087Schmidtke K, 1998, J NUCL MED, V39, P155Ghelarducci B, 1997, ARCH ITAL BIOL, V135, P369HODGES JR, 1994, J NEUROL NEUROSUR PS, V57, P605HODGES JR, 1990, J NEUROL NEUROSUR PS, V53, P834HODGES JR, 1990, BRAIN, V113, P639HEATH RG, 1976, J NEUROL NEUROSUR PS, V39, P1037

Akinetic Mutism and Cognitive-Affective Syndrome Caused by Unilateral PICA Infarction

A 42-year-old man with left posterior inferior cerebellar artery (PICA) infarction presented with akinetic mutism and cognitive impairment. Initially he suffered from akinetic mutism and MRI-documented infarction in the distribution of the left PICA. Twelve days later he developed cognitive impairment. Neuropsychological tests were performed, with the results corrected for age and education being compared with published Korean norms. Impaired performances were evident on executive function testing, with difficulties in planning, abstract reasoning, set-shifting, and perseveration. Akinetic mutism and cognitive-affective syndrome may be a manifestation of unilateral PICA infarction

A Case of Cardiac Cephalalgia Showing Reversible Coronary Vasospasm on Coronary Angiogram

Background Under certain conditions, exertional headaches may reflect coronary ischemia Case Report A 44-year-old woman developed intermittent exercise-induced headaches with chest tightness over a period of 10 months Cardiac catheterization followed by acetylcholine provocation demonstrated a right coronary artery spasm with chest tightness, headache, and ischemic effect of continuous electrocardiography changes The patient`s headache disappeared following ultra-arterial nitroglycerine injection Conclusions A coronary angiogram with provocation study revealed variant angina and cardiac cephalalgia, as per the International Classification of Headache Disorders (code 10 6) We report herein a patient with cardiac cephalalgia that manifested as reversible coronary vasospasm following an acetylcholine provocation test J Clin Neurol 2010;6:99-101*INT HEAD SOC HEAD, 2004, CEPHALALGIA S1, V24, P1, DOI DOI 10.1111/J.1468-2982.2004.00653.XChen SP, 2004, EUR NEUROL, V51, P221, DOI 10.1159/000078489Martinez HR, 2002, HEADACHE, V42, P1029Lanza GA, 2000, LANCET, V356, P998Lance JW, 1998, HEADACHE, V38, P315Lipton RB, 1997, NEUROLOGY, V49, P813Grace A, 1997, CEPHALALGIA, V17, P195BOWEN J, 1993, HEADACHE, V33, P238MELLER ST, 1992, NEUROSCIENCE, V48, P501VERNAY D, 1989, HEADACHE, V29, P350LEFKOWITZ D, 1982, ARCH NEUROL-CHICAGO, V39, P130

Prediction of cognitive impairment via deep learning trained with multi-center neuropsychological test data

Background Neuropsychological tests (NPTs) are important tools for informing diagnoses of cognitive impairment (CI). However, interpreting NPTs requires specialists and is thus time-consuming. To streamline the application of NPTs in clinical settings, we developed and evaluated the accuracy of a machine learning algorithm using multi-center NPT data. Methods Multi-center data were obtained from 14,926 formal neuropsychological assessments (Seoul Neuropsychological Screening Battery), which were classified into normal cognition (NC), mild cognitive impairment (MCI) and Alzheimers disease dementia (ADD). We trained a machine learning model with artificial neural network algorithm using TensorFlow (https://www.tensorflow.org) to distinguish cognitive state with the 46-variable data and measured prediction accuracies from 10 randomly selected datasets. The features of the NPT were listed in order of their contribution to the outcome using Recursive Feature Elimination. Results The ten times mean accuracies of identifying CI (MCI and ADD) achieved by 96.66 ± 0.52% of the balanced dataset and 97.23 ± 0.32% of the clinic-based dataset, and the accuracies for predicting cognitive states (NC, MCI or ADD) were 95.49 ± 0.53 and 96.34 ± 1.03%. The sensitivity to the detection CI and MCI in the balanced dataset were 96.0 and 96.0%, and the specificity were 96.8 and 97.4%, respectively. The time orientation and 3-word recall score of MMSE were highly ranked features in predicting CI and cognitive state. The twelve features reduced from 46 variable of NPTs with age and education had contributed to more than 90% accuracy in predicting cognitive impairment. Conclusions The machine learning algorithm for NPTs has suggested potential use as a reference in differentiating cognitive impairment in the clinical setting.The publication costs, design of the study, data management and writing the manuscript for this article were supported by the Ministry of Education of the Republic of Korea and the National Research Foundation of Korea (NRF-2017S1A6A3A01078538), Korea Ministry of Health & Welfare, and from the Original Technology Research Program for Brain Science through the National Research Foundation of Korea funded by the Korean Government (MSIP; No. 2014M3C7A1064752)

Alterations in cognitive function and blood biomarkers following transcranial direct current stimulation in patients with amyloid positron emission tomography-positive Alzheimer's disease: a preliminary study

Introduction: Alzheimer's disease (AD), the most common form of dementia, is characterized by progressive cognitive decline. To address this, we conducted a randomized, double-blinded, sham-controlled study to investigate the therapeutic potential of transcranial direct current stimulation (tDCS) on patients with amyloid positron emission tomography (PET)- positive AD.Methods: Participants already undergoing pharmacological treatment and testing positive for amyloid PET were divided into Active-tDCS (n = 8) and Sham-tDCS (n = 8) groups. For 12 weeks, participants or their caregivers administered daily bi-frontal tDCS (YMS-201B+, Ybrain Inc., Seongnam, Korea) at home (2 mA, 30 min). Pre- and post-intervention assessments included neuropsychological tests and blood sample measurements for oligomerized beta-amyloid.Results: The Active-tDCS group demonstrated significant improvements in cognitive domains such as language abilities, verbal memory, and attention span and in frontal lobe functions compared to the Sham-tDCS group. Furthermore, the Active-tDCS group showed a marked reduction in post-intervention plasma A beta oligomerization tendency level, suggesting changes in pivotal AD-associated biomarkers.Discussion: Our results emphasize the potential therapeutic benefits of tDCS for mild AD patients with amyloid PET positivity and stress the urgency for broader research, considering the global challenges of dementia and the need to pursue innovative therapeutic strategies.11Nsciescopu

The Effects of Donepezil on 15-Item Geriatric Depression Scale Structure in Patients with Alzheimer Disease

Background/Aims: In Alzheimer disease (AD), depression is among the most common accompanying neuropsychiatric symptoms and has different clinical manifestations when compared with early-life depression. In patients with drug-naïve AD, we tried to explore the structure of the 15-item Geriatric Depression Scale (GDS15) and the effect of donepezil on these substructures. Methods: GDS15, cognitive function, and activities of daily living function tests were administered to 412 patients with probable AD who had not been medicated before visiting the hospital. Using principal component analysis, three factors were identified. The patients with AD who received only donepezil were retrospectively analyzed and we compared the change of cognition and GDS15 subgroup after donepezil medication. Results: Our study identified three factors and revealed that the GDS15 may be comprised of a heterogeneous scale. The Barthel index was significantly correlated with factor 1 (positively) and factor 2 (negatively). The Korean version of the MMSE (K-MMSE) was significantly correlated with factor 2 and factor 3. Compared to the baseline state, K-MMSE and GDS15 showed significant improvement after taking donepezil. Among GDS15 subgroups, factor 2 and factor 3 showed significant improvement after donepezil treatment. Conclusions: These results suggest that the GDS15 may be comprised of a heterogeneous scale and donepezil differentially affects the GDS15 subgroup in AD

Availability analysis of subsea blowout preventer using Markov model considering demand rate

Availabilities of subsea Blowout Preventers (BOP) in the Gulf of Mexico Outer Continental Shelf (GoM OCS) is investigated using a Markov method. An updated β factor model by SINTEF is used for common-cause failures in multiple redundant systems. Coefficient values of failure rates for the Markov model are derived using the β factor model of the PDS (reliability of computer-based safety systems, Norwegian acronym) method. The blind shear ram preventer system of the subsea BOP components considers a demand rate to reflect reality more. Markov models considering the demand rate for one or two components are introduced. Two data sets are compared at the GoM OCS. The results show that three or four pipe ram preventers give similar availabilities, but redundant blind shear ram preventers or annular preventers enhance the availability of the subsea BOP. Also control systems (PODs) and connectors are contributable components to improve the availability of the subsea BOPs based on sensitivity analysis