Exploring the capability of wireless near infrared spectroscopy as a portable seizure detection device for epilepsy patients

AbstractPurposeNear infrared spectroscopy (NIRS) has proved useful in measuring significant hemodynamic changes in the brain during epileptic seizures. The advance of NIRS-technology into wireless and portable devices raises the possibility of using the NIRS-technology for portable seizure detection.MethodsThis study used NIRS to measure changes in oxygenated (HbO), deoxygenated (HbR), and total hemoglobin (HbT) at left and right side of the frontal lobe in 33 patients with epilepsy undergoing long-term video-EEG monitoring. Fifteen patients had 34 focal seizures (20 temporal-, 11 frontal-, 2 parietal-lobe, one unspecific) recorded and analyzed with NIRS. Twelve parameters consisting of maximum increase and decrease changes of HbO, HbR and HbT during seizures (1min before- to 3min after seizure-onset) for left and right side, were compared with the patients’ own non-seizure periods (a 2-h period and a 30-min exercise-period). In both non-seizure periods a 4min moving windows with maximum overlapping were applied to find non-seizure maxima of the 12 parameters. Detection was defined as positive when seizure maximum change exceeded non-seizure maximum change.ResultsWhen analyzing the 12 parameters separately the positive seizure detection was in the range of 6–24%. The increase in hemodynamics was in general better at detecting seizures (15–24%) than the decrease in hemodynamics (6–18%) (P=0.02).ConclusionNIRS did not seem to be a suitable technology for generic seizure detection given the device, settings, and methods used in this study. There are still several challenges to overcome before the NIRS-technology can be used as a home-monitoring seizure detection device

Guiding 3D U-nets with signed distance fields for creating 3D models from images

Morphological analysis of the left atrial appendage is an important tool to assess risk of ischemic stroke. Most deep learning approaches for 3D segmentation is guided by binary labelmaps, which results in voxelized segmentations unsuitable for morphological analysis. We propose to use signed distance fields to guide a deep network towards morphologically consistent 3D models. The proposed strategy is evaluated on a synthetic dataset of simple geometries, as well as a set of cardiac computed tomography images containing the left atrial appendage. The proposed method produces smooth surfaces with a closer resemblance to the true surface in terms of segmentation overlap and surface distance.Comment: MIDL 2019 [arXiv:1907.08612

Early diagnosis of amyotrophic lateral sclerosis by threshold tracking and conventional transcranial magnetic stimulation

© 2021 The Authors. European Journal of Neurology published by John Wiley & Sons Ltd on behalf of European Academy of Neurology. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.Background and purpose: Short-interval intracortical inhibition by threshold tracking (T-SICI) has been proposed as a diagnostic tool for amyotrophic lateral sclerosis (ALS) but has not been compared directly with conventional amplitude measurements (A-SICI). This study compared A-SICI and T-SICI for sensitivity and clinical usefulness as biomarkers for ALS. Methods: In all, 104 consecutive patients referred with suspicion of ALS were prospectively included and were subsequently divided into 62 patients with motor neuron disease (MND) and 42 patient controls (ALS mimics) by clinical follow-up. T-SICI and A-SICI recorded in the first dorsal interosseus muscle (index test) were compared with recordings from 53 age-matched healthy controls. The reference standard was the Awaji criteria. Clinical scorings, conventional nerve conduction studies and electromyography were also performed on the patients. Results: Motor neuron disease patients had significantly reduced T-SICI and A-SICI compared with the healthy and patient control groups, which were similar. Sensitivity and specificity for discriminating MND patients from patient controls were high (areas under the receiver operating characteristic curves 0.762 and 0.810 for T-SICI and A-SICI respectively at 1-3.5 ms). Paradoxically, T-SICI was most reduced in MND patients with the fewest upper motor neuron (UMN) signs (Spearman ρ = 0.565, p = 4.3 × 10-6 ). Conclusions: Amplitude-based measure of cortical inhibition and T-SICI are both sensitive measures for the detection of cortical involvement in MND patients and may help early diagnosis of ALS, with T-SICI most abnormal before UMN signs have developed. The gradation in T-SICI from pathological facilitation in patients with minimal UMN signs to inhibition in those with the most UMN signs may be due to progressive degeneration of the subset of UMNs experiencing facilitation.info:eu-repo/semantics/publishedVersio

Low rate of reoperations after acute type A aortic dissection repair from The Nordic Consortium Registry

ObjectivesTo describe the relationship between the extent of primary aortic repair and the incidence of reoperations after surgery for type A aortic dissection.MethodsA retrospective cohort of 1159 patients treated for type A aortic dissection at eight Nordic low- to medium-sized cardiothoracic centers from 2005 to 2014. Data were gathered from patient records and national registries. Patients were separately divided into 3 groups according to the distal anastomoses technique (ascending aorta [n = 791], hemiarch [n = 247], and total arch [n = 66]), and into 2 groups for proximal repair (aortic root replacement [n = 285] and supracoronary repair [n = 832]). Freedom from reoperation was estimated with cumulative incidence survival and Fine-Gray competing risk regression model was used to identify independent risk factors for reoperation.ResultsThe median follow-up was 2.7 years (range, 0-10 years). Altogether 51 out of 911 patients underwent reoperation. Freedom from distal reoperation at 5 years was 96.9%, with no significant difference between the groups (P = .22). Freedom from proximal reoperation at 5 years was 97.8%, with no difference between the groups (P = .84). Neither DeBakey classification nor the extent of proximal or distal repair predicted freedom from a later reoperation. The only independent risk factor associated with a later proximal reoperation was a history of connective tissue disease.ConclusionsType A aortic dissection repair in low- to medium-volume centers was associated with a low reoperation rate and satisfactory midterm survival. The extent of the primary repair had no significant influence on reoperation rate or midterm survival.</p

A RT-qPCR system using a degenerate probe for specific identification and differentiation of SARS-CoV-2 Omicron (B.1.1.529) variants of concern

Fast surveillance strategies are needed to control the spread of new emerging SARS-CoV-2 variants and gain time for evaluation of their pathogenic potential. This was essential for the Omicron variant (B.1.1.529) that replaced the Delta variant (B.1.617.2) and is currently the dominant SARS-CoV-2 variant circulating worldwide. RT-qPCR strategies complement whole genome sequencing, especially in resource lean countries, but mutations in the targeting primer and probe sequences of new emerging variants can lead to a failure of the existing RT-qPCRs. Here, we introduced an RT-qPCR platform for detecting the Delta- and the Omicron variant simultaneously using a degenerate probe targeting the key ΔH69/V70 mutation in the spike protein. By inclusion of the L452R mutation into the RT-qPCR platform, we could detect not only the Delta and the Omicron variants, but also the Omicron sub-lineages BA.1, BA.2 and BA.4/BA.5. The RT-qPCR platform was validated in small- and large-scale. It can easily be incorporated for continued monitoring of Omicron sub-lineages, and offers a fast adaption strategy of existing RT-qPCRs to detect new emerging SARS-CoV-2 variants using degenerate probes.</p

Compare the differences of synonymous codon usage between the two species within cardiovirus

<p>Abstract</p> <p>Background</p> <p>Cardioviruses are positive-strand RNA viruses in the Picornaviridae family that can cause enteric infection in rodents and also been detected at lower frequencies in other mammals such as pigs and human beings. The Cardiovirus genus consists two distinct species: Encephalomyocarditis virus (EMCV) and Theilovirus (ThV). There are a lot differences between the two species. In this study, the differences of codon usage in EMCV and ThV were compared.</p> <p>Results</p> <p>The mean ENC values of EMCV and ThV are 54.86 and 51.08 respectively, higher than 40.And there are correlations between (C+G)₁₂% and (C+G)₃% for both EMCV and ThV (r = -0.736;r = 0.986, P < 0.01, repectively). For ThV the (C+G)₁₂%, (C+G)₃%, axis <it>f</it>'₁and axis <it>f</it>'₂had a significant correlations respectively but not for EMCV. According to the RSCU values, the EMCV species seemed to prefer U, G and C ending codon, while the ThV spice seemed to like using U and A ending codon. However, in both genus AGA for Arg, AUU for Ile, UCU for Ser, and GGA for Gly were chosen preferentially. Correspondence analysis detected one major trend in the first axis (<it>f</it>'₁) which accounted for 22.89% of the total variation, and another major trend in the second axis (<it>f</it>'₂) which accounted for 17.64% of the total variation. And the plots of the same serotype seemed at the same region at the coordinate.</p> <p>Conclusion</p> <p>The overall extents of codon usage bias in both EMCV and ThV are low. The mutational pressure is the main factor that determines the codon usage bias, but the (C+G) content plays a more important role in codon usage bias for ThV than for EMCV. The synonymous codon usage pattern in both EMCV and ThV genes is gene function and geography specific, but not host specific. Maybe the serotype is one factor effected the codon bias for ThV, and location has no significant effect on the variations of synonymous codon usage in these virus genes.</p