Anticoagulation strategies in patients with coexisting traumatic intracranial hematomas and cerebral venous sinus thrombosis: an observational cohort study.

Purpose: Post-traumatic cerebral venous sinus thrombosis (ptCVT) is a rare but serious complication of traumatic brain injury (TBI). Managing ptCVT is challenging due to the concurrent risk of traumatic intracranial hematoma (ICH) expansion. Limited data exists on the safety and efficacy of anticoagulation therapy (ACT) in these cases.

Modeling Colloidal Particle Aggregation Using Cluster Aggregation with Multiple Particle Interactions.

In this study, we investigate the aggregation dynamics of colloidal silica by generating simulated structures and comparing them to experimental data gathered through scanning transmission electron microscopy (STEM). More specifically, diffusion-limited cluster aggregation and reaction-limited cluster aggregation models with different functions for the probability of particles sticking upon contact were used. Aside from using a constant sticking probability, the sticking probability was allowed to depend on the masses of the colliding clusters and on the number of particles close to the collision between clusters.

Hand Pose Estimation by Fusion of Inertial and Magnetic Sensing Aided by a Permanent Magnet.

Tracking human body motions using inertial sensors has become a well-accepted method in ambulatory applications since the subject is not confined to a lab-bounded volume. However, a major drawback is the inability to estimate relative body positions over time because inertial sensor information only allows position tracking through strapdown integration, but does not provide any information about relative positions. In addition, strapdown integration inherently results in drift of the estimated position over time.

Can prolonged QTc and cTNT level predict the acute and long-term prognosis of stroke?

Background: Previous studies in patients with stroke indicate that QTc prolongation and elevated cTNT are related to increased risk of all-cause and cardiovascular mortality.

Methods: We analysed the importance of electrocardiographic (ECG) abnormalities and elevated serum cardiac troponin (cTNT)--at baseline examination--as potential predictors for acute and long-term mortalities after stroke in a follow-up of 478 patients with a mean age of 78 years.

Results: In a multivariate analysis, strong predictors for poor prognosis during the acute phase were: elevated cTNT (p=0.

Diffuse reflectance spectroscopy measurements for tissue-type discrimination during deep brain stimulation.

Diffuse reflectance spectroscopy as a method for improving intracerebral guidance during functional neurosurgery has been investigated. An optical probe was developed for measurements during stereotactic and functional neurosurgery in man. The aim of the study was to investigate the spectral differences between white and grey matter and between white matter and functional targets.

A laser Doppler system for intracerebral measurements during stereotactic neurosurgery.

A laser Doppler system for intracerebral measurements during stereotactic and functional neurosurgery is presented. The system comprises a laser Doppler perfusion monitor, an optical probe adapted for the Leksell Stereotactic System and a personal computer with software for acquisition, data analysis and presentation. The software makes it possible to present both the perfusion and the total backscattered light intensity (TLI) in real-time.

Intracerebral microvascular measurements during deep brain stimulation implantation using laser Doppler perfusion monitoring.

The aim of the study was to investigate if laser Doppler perfusion monitoring (LDPM) can be used in order to differentiate between gray and white matter and to what extent microvascular perfusion can be recorded in the deep brain structures during stereotactic neurosurgery. An optical probe constructed to fit in the Leksell Stereotactic System was used for measurements along the trajectory and in the targets (globus pallidus internus, subthalamic nucleus, zona incerta, thalamus) during the implantation of deep brain stimulation leads (n = 22). The total backscattered light intensity (TLI) reflecting the grayness of the tissue, and the microvascular perfusion were captured at 128 sites.

Optical measurements during experimental stereotactic radiofrequency lesioning.

The aim of this study was to evaluate in vivo a laser Doppler measurement system in porcine brain tissue during thermal lesioning. A 2-mm monopolar radiofrequency lesioning electrode was equipped with optical fibers in order to monitor the lesioning procedure. Laser Doppler and backscattered light intensity signals were measured along the electrode trajectory and during bilateral lesioning in the central gray (70, 80 and 90 degrees C, n = 14).

In vitro measurements of optical properties of porcine brain using a novel compact device.

Knowledge of the optical properties of tissues can be applied in numerous medical and scientific fields, including cancer diagnostics and therapy. There are many different ways of determining the optical properties of turbid media. The paper describes measurements of the optical properties of porcine brain tissue using novel instrumentation for simultaneous absorption and scattering characterisation of small turbid samples.

Radio frequency electrode system for optical lesion size estimation in functional neurosurgery.

Radiofrequency (RF) lesioning in the human brain is one possible surgical therapy for severe pain as well as movement disorders. One obstacle for a safer lesioning procedure is the lack of size monitoring. The aim of this study was to investigate if changes in laser Doppler or intensity signals could be used as markers for size estimation during experimental RF lesioning.

Knowledge representation forms for data mining methodologies as applied in thoracic surgery.

Typical ways of disseminating and using results of clinical research are scientific journals and reports. Presentation forms are condensed and comprehensible mainly to the experts following the specific topics. A vast amount of information remains unutilized due to the complex form of presenting the knowledge.

Quantitative data analysis for exploring outcomes in cardiac surgery.

The article focuses on possibilities of statistical knowledge exploration to predict outcomes of surgical treatments. The outcomes were defined in relation to the measured peri- and intraoperative data, as well as follow-up patient questionnaire. Clinical consequences are expected in terms of a smaller data set with a better ability to predict the surgery outcomes and a better cost performance.

Gut intramucosal pH and intraluminal PO2 in a porcine model of peritonitis or haemorrhage.

The tonometric method of detecting decreased gut intramucosal pH (pHi) is based on the fact that carbon dioxide can diffuse through the wall of the silastic balloon of the tonometer. By using deoxified saline and measuring PO2 as well as PCO2 this study aimed to follow changes in mucosal PO2 and relate them to changes in pHi in peritonitis versus haemorrhage. Twenty five pigs were used.

Changes in gut intramucosal pH and gut oxygen extraction ratio in a porcine model of peritonitis and hemorrhage.

Objective: To establish the relationship between gut intramucosal pH and blood flow to the gut, gut oxygen delivery, and gut oxygen extraction ratio in a porcine model of peritonitis and hemorrhage.

Design: Prospective, controlled study.

Setting: Experimental laboratory in a university teaching hospital.

Intestinal mucosal injury during porcine faecal peritonitis.

Objective: To assess the incidence of intestinal mucosal injury during faecal peritonitis in pigs, the relation of such lesions to haemodynamic variables, intramucosal pH (pHi), and endothelial adherence of polymorphonuclear leucocytes (PMNs).

Design: Experimental laboratory study.

Setting: University department of surgery, Sweden.

Intraoperative colonic lavage and primary anastomosis--an alternative to Hartmann procedure in emergency surgery of the left colon.

Objective: To assess whether intraoperative lavage and primary resection with anastomosis is a safe alternative to a Hartmann procedure in emergency surgery of the left colon.

Design: Retrospective study.

Setting: University hospital.

Gut perfusion in experimental shock.

The gut seems to play a very important role in the shock syndrome, since it is an organ that is early and profoundly affected by insufficient tissue perfusion. Once affected by inadequate oxygenation, the gut can also act as a "motor of shock" by the release of toxic mediators and through the translocation of bacteria and bacterial endotoxins. It thus would be of benefit to monitor the gut during shock, and this can be accomplished by tonometry, a method to calculate the intramucosal pH (pHi).

Subcutaneous and gut tissue perfusion and oxygenation changes as related to oxygen transport in experimental peritonitis.

Peritonitis and septic shock may lead to tissue hypoxia, but this risk is not identical in all organ systems. This study was undertaken to measure changes in tissue oxygenation and perfusion in the gut wall and subcutaneous tissue, respectively, and to examine their relation to oxygen delivery and consumption. Twelve pigs were anesthesized and mechanically ventilated.

Delayed treatment with an LTD4/E4 antagonist limits pulmonary edema in endotoxic pigs.

We used a selective leukotriene (LT) D4/E4 receptor antagonist (LY 203647) to investigate the role of cysteinyl LTs as mediators of several important pathophysiological events in a porcine model of endotoxic shock. Pentobarbital-anesthetized pigs (11.8-17.

Leukotriene C4 induces mesenteric hypoperfusion and intestinal intramural acidosis in pigs.

We examined the effect of intravenous infusion of graded doses of authentic leukotriene (LT) C4 on several physiological variables in pentobarbital-anesthetized immature swine. Mesenteric blood flow (Qsma) was measured using an ultrasonic flow probe and ileal intramucosal hydrogen ion concentration ([H+]I) was estimated tonometrically. Three groups were studied.

Increased intestinal permeability in endotoxic pigs. Mesenteric hypoperfusion as an etiologic factor.

Infusing pigs with lipopolysaccharide (LPS) decreases superior mesenteric artery blood flow (Qsma), suggesting that mesenteric hypoperfusion may be responsible for LPS-induced alterations in gut mucosal permeability. To test this hypothesis, we studied four groups of anesthetized swine. Group 1 animals (N = 6) were infused with LPS (250 micrograms/kg over 1 hour beginning at 60 minutes) and continuously resuscitated with Ringer's lactate (48 mL/kg per hour).

Beneficial effects of LY203647, a novel leukotriene C4/D4 antagonist, on pulmonary function and mesenteric perfusion in a porcine model of endotoxic shock and ARDS.

The sulfidopeptide leukotrienes (LT) have been implicated as important pathophysiological mediators in septic shock. To further define the role of these compounds, we utilized a porcine endotoxicosis model to study the effects of pre- and concurrent treatment with LY203647, a novel LT receptor antagonist. Pentobarbital-anesthetized pigs (13-20 kg) were mechanically ventilated with 100% O2.

Validation of tonometric measurement of gut intramural pH during endotoxemia and mesenteric occlusion in pigs.

Tonometry is a minimally invasive method for estimating gastrointestinal intramural pH (pHi). Tissue pH is calculated by using the Henderson-Hasselbalch equation and measurements of arterial [HCO-3] and CO2 tension (PCO3) of saline contained in a Silastic balloon within the lumen of the gut. The validity of the method rests on two key assumptions: 1) PCO2 in saline in the tonometer balloon is similar to tissue PCO2 and 2) tissue and arterial [HCO-3] are similar.