Neural network analysis of nocturnal SpO signal enables easy screening of sleep apnea in patients with acute cerebrovascular disease.

Current diagnostics of sleep apnea relies on the time-consuming manual analysis of complex sleep registrations, which is impractical for routine screening in hospitalized patients with a high probability for sleep apnea, e.g. those experiencing acute stroke or transient ischemic attacks (TIA).

Acute stroke and TIA patients have specific polygraphic features of obstructive sleep apnea.

Purpose: Obstructive sleep apnea (OSA) is associated with increased risk for stroke, which is known to further impair respiratory functions. However, it is unknown whether the type and severity of respiratory events are linked to stroke or transient ischemic attack (TIA). Thus, we investigate whether the characteristics of individual respiratory events differ between patients experiencing TIA or acute ischemic stroke and matched patients with clinically suspected sleep-disordered breathing.

Polysomnographic scoring of sleep bruxism events is accurate even in the absence of video recording but unreliable with EMG-only setups.

Purpose: To determine the accuracy of scoring masticatory muscle activity (MMA) events in seven different polysomnography (PSG) setups.

Methods: Nineteen volunteers (13 females, 6 males, age 31.1 ± 12.

Home Polysomnography Reveals a First-Night Effect in Patients With Low Sleep Bruxism Activity.

Study Objectives: To examine the presence of a first-night effect (FNE) and the level of internight variability in sleep bruxism (SB) activity when a self-applicable electrode set is used in home polysomnography (PSG) in a sample of subjects with possible SB.

Methods: Fourteen females and two males aged 38.3 ± 9.

Success Rate and Technical Quality of Home Polysomnography With Self-Applicable Electrode Set in Subjects With Possible Sleep Bruxism.

Using sleep laboratory polysomnography (PSG) is restricted for the diagnosis of only the most severe sleep disorders due to its low availability and high cost. Home PSG is more affordable, but applying conventional electroencephalography (EEG) electrodes increases its overall complexity and lowers the availability. Simple, self-administered single-channel EEG monitors on the other hand suffer from poor reliability.

Screen-printed ambulatory electrode set enables accurate diagnostics of sleep bruxism.

Currently, definite diagnosis of sleep bruxism requires polysomnography. However, it is restrictedly available, and too cumbersome and expensive for the purpose. The aim of this study was to introduce an ambulatory electrode set and evaluate its feasibility for more cost-effective diagnostics of sleep bruxism.

Assessment of the suitability of using a forehead EEG electrode set and chin EMG electrodes for sleep staging in polysomnography.

Recently, a number of portable devices designed for full polysomnography at home have appeared. However, current scalp electrodes used for electroencephalograms are not practical for patient self-application. The aim of this study was to evaluate the suitability of recently introduced forehead electroencephalogram electrode set and supplementary chin electromyogram electrodes for sleep staging.

Forehead EEG electrode set versus full-head scalp EEG in 100 patients with altered mental state.

Background: Acute EEG is vastly underutilized in acute neurological settings. The most common reason for this is simply the fact that acute EEG is not available when needed or getting EEG is delayed as it requires trained technicians and equipment to be properly recorded. We have recently described a handy disposable forehead EEG electrode set that is suitable for acute emergency EEG recordings.

Effect of oxygen desaturation threshold on determination of OSA severity during weight loss.

Purpose: Weight loss leads to improvement of obstructive sleep apnea (OSA), based on frequency of respiratory events (apnea-hypopnea index, AHI). However, AHI does not incorporate the severity of individual obstruction events. The American Academy of Sleep Medicine suggests two alternative oxygen desaturation thresholds (ODT) for scoring of hypopneas.

Effect of different oxygen desaturation threshold levels on hypopnea scoring and classification of severity of sleep apnea.

Purpose: Recently, there has been a debate about the rules used to score hypopnea events. The purpose of this study was to examine the effect of different oxygen desaturation threshold (ODT) levels on the apnea-hypopnea index (AHI) and on a recently introduced parameter, adjusted AHI. Adjusted AHI incorporates the severity of individual breathing cessation events.

A Handy EEG Electrode Set for patients suffering from altered mental state.

Although electroencephalography (EEG) is an important diagnostic tool for investigating patients with unexplained altered mental state (AMS), recording of emergency EEG is not a clinical routine. This is mainly due to the cumbersome electrode solutions. A Handy EEG Electrode Set consists of ten EEG, two EOG, two ground and two commutative reference hydrogel-coated silver wire electrodes attached to a thin polyester carrier film.

Novel screen printed electrode set for routine EEG recordings in patients with altered mental status.

There is a growing need for an easy to use screening tool for the assessment of brain's electrical function in patients with altered mental status (AMS). The purpose of this study is to give a brief overview of the state-of-the-art in electrode technology, and to present a novel sub-hairline electrode set developed in our research group. Screen-printing technology was utilized to construct the electrode set consisting of ten electroencephalography (EEG) electrodes, two electrooculography (EOG) electrodes, two ground electrodes and two reference electrodes.

New disposable forehead electrode set with excellent signal quality and imaging compatibility.

The use of emergency electroencephalography (EEG) in clinical practice is limited in part due to the lack of commercially available EEG monitoring sets that are suitable for rapid and simple use. The aim of this study was to develop a rapid and simple-to-use disposable forehead EEG electrode set for routine use that is also suitable for long-term monitoring. The EEG set we developed consists of 12 hydrogel-coated electrodes (10 recording electrodes, plus a reference and ground electrode) attached to a solid polymer film.

Formation and retention of staphylococcal biofilms on DLC and its hybrids compared to metals used as biomaterials.

Staphylococcus epidermidis and Staphylococcus aureus cause most of the implant-related infections. Antibiotic treatment often fails and cure requires surgical intervention. It was hypothesized that biomaterial coatings resistant to biofilms offer a preventive option.

Osteogenesis of human mesenchymal stem cells on micro-patterned surfaces.

Osteogenic responses of human mesenchymal stromal cells (hMSCs) were compared on square-patterned, inverse square-patterned, and planar titanium, chromium, diamond-like carbon (DLC), and tantalum; hypothesis was that both the materials and patterns affect osteogenesis. Samples were produced using photolithography and physical vapor deposition. Early-marker alkaline phosphatase (ALP) and mid-markers, small body size and mothers against decapentaplegic-related protein-1 (SMAD1), runt-related transcription factor-2 (RUNX2), and osteopontin were studied using quantitative real-time polymerase chain reaction.

In vitro adhesion of staphylococci to diamond-like carbon polymer hybrids under dynamic flow conditions.

This study compares the ability of selected materials to inhibit adhesion of two bacterial strains commonly implicated in implant-related infections. These two strains are Staphylococcus aureus (S-15981) and Staphylococcus epidermidis (ATCC 35984). In experiments we tested six different materials, three conventional implant metals: titanium, tantalum and chromium, and three diamond-like carbon (DLC) coatings: DLC, DLC-polydimethylsiloxane hybrid (DLC-PDMS-h) and DLC-polytetrafluoroethylene hybrid (DLC-PTFE-h) coatings.

Enhancement of silicon using micro-patterned surfaces of thin films.

Micro-textured biomaterials might enhance cytocompatibility of silicon-based micro-electro-mechanical system (bio-MEMS) dummies. Photolithography-physical vapour deposition was used to produce diamond-like carbon (DLC) or Ti squares and circles on silicon, and also their inverse replicas; then DLC and Ti were compared for their guiding potential, using a SaOS-2 cell model. Scanning electron microscopy at 48 hours indicated cells were well-spread on large-sized patterns (several cells on one pattern) and assumed the geometrical architecture of underlying features.

Surface characterization and in vitro biocompatibility assessment of photosensitive polyimide films.

Polyimide (PI) is a commonly used polymer in microelectronics. Recently, numerous PI-based flexible neural interfaces have been developed for reducing mechanical mismatch between rigid implant and soft neural tissue. Most approaches employ non-photosensitive PI, which has been proven earlier to be biocompatible.

Adhesion, spreading and osteogenic differentiation of mesenchymal stem cells cultured on micropatterned amorphous diamond, titanium, tantalum and chromium coatings on silicon.

It was hypothesized that human mesenchymal stromal cell (hMSC) can be guided by patterned and plain amorphous diamond (AD), titanium (Ti), tantalum (Ta) and chromium (Cr) coatings, produced on silicon wafer using physical vapour deposition and photolithography. At 7.5 h hMSCs density was 3.

Improved adherence and spreading of Saos-2 cells on polypropylene surfaces achieved by surface texturing and carbon nitride coating.

The adhesion and contact guidance of human primary osteogenic sarcoma cells (Saos-2) were characterized on smooth, microstructured (MST) and micro- and nano-structured (MNST) polypropylene (PP) and on the same samples with a silicon-doped carbon nitride (C(3)N(4)-Si) coating. Injection molding was used to pattern the PP surfaces and the coating was obtained by using ultra-short pulsed laser deposition (USPLD). Surfaces were characterized using atomic force microscopy and surface energy components were calculated according to the Owens-Wendt model.

Patterned macroarray plates in comparison of bacterial adhesion inhibition of tantalum, titanium, and chromium compared with diamond-like carbon.

Staphylococcus aureus device-related infection is a common complication in implantology. Bacterial adhesion on implant surfaces is the initial step in the infective process. The aim was to develop a method suitable for quantitative bacterial adherence studies and to test a new diamond-like carbon (DLC) coating against commonly used metallic biomaterials with regards to Staphylococcus aureus adhesion.

Fabrication and testing of polyimide-based microelectrode arrays for cortical mapping of evoked potentials.

Modern microfabrication techniques make it possible to develop microelectrode arrays that may be utilized not only in neurophysiological research but also in the clinic, e.g. in neurosurgery and as elements of neural prostheses.

Development of flexible microelectrode arrays for recording cortical surface field potentials.

The fabrication, characterization and application of an 8-channel flexible microelectrode array for recording cortical surface field potentials is described. Polyimide-based microelectrode arrays were fabricated by using photolithography and physical vapour deposition (PVD) methods. Polyimide was chosen as the substrate and insulation material due to its suitable mechanical properties and biocompatibility.