Diffusion tensor imaging findings in the multiple sclerosis patients and their relationships to various aspects of disability.

BACKGROUND: The aim of the study was to assess microstructural changes within strategic brain regions in multiple sclerosis (MS) patients, using diffusion tensor imaging (DTI), with regard to various aspects of disability. MATERIAL AND METHODS: The study comprised 50 patients with relapsing-remitting MS (37 women, 13 men, mean age 36.4 yrs) and 27 age- and sex-matched controls. Using DTI, fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were obtained within corpus callosum (CC), both thalami (TH) and middle cerebellar peduncles (MCP). Disability was assessed using Expanded Disability Status Scale (EDSS), MS Functional Composite (MSFC), Symbol Digit Modalities Test (SDMT) and Fatigue Severity Scale (FSS). DTI indices were compared between the patients and controls and in the MS group - referred to disability measures. RESULTS: Significant decrease in FA and increase in ADC within CC and both TH were found in MS patients compared to the controls. DTI indices within CC and TH correlated significantly with SDMT score, and within TH and MCP - with MSFC manual dexterity measure. CONCLUSIONS: Changes in DTI measures in normal appearing white and grey matter in the MS patients indicate subtle alterations of the tissue integrity. An occult damage to the strategic brain regions may contribute to various aspects of disability due to MS.

[Development of the German diagnosis-related groups (G-DRG) for ophthalmology from 2004 to 2012]. / Entwicklung der "German diagnosis related groups" in der Augenheilkunde von 2004 bis 2012.

BACKGROUND: In 2003 the German diagnosis-related groups (G-DRG) were introduced for reimbursement of inpatient treatment. The aim of this study was to analyze the development of G-DRGs in ophthalmology in Germany (MDC02) from 2004 to 2012 by means of data from the Institute for the Reimbursement System in Hospitals (InEK). METHODS: The data regarding costs, cost weighting and mean length of stay (LOS) from the G-DRG reports of the InEK from 2004 to 2012 in 9 representative surgical and non-surgical ophthalmological treatment case groups were analyzed. Differences in the coding system as well as alterations between the G-DRGs over the course of time were taken into consideration. The cost weightings were calculated taking the year 2004 as the baseline and are presented in the form of graphs. RESULTS: The selected cases cover 54% of all G-DRG cases used by the InEK for G-DRG calculations. For 6 out of the 9 case groups there was a cost/reimbursement reduction by nearly one third of the calculated costs by InEK from 2004 to 2012. Only one case group showed an increase in costs by 23% which can be explained by alterations in graft costs in this case group. The mean LOS decreased over the time period in the 9 groups investigated by up to 40% and on average by -22.3%. CONCLUSIONS: The annually calculated costs of the InEK directly influence the calculation of the cost weightings and reimbursement and are therefore important for every hospital. During the time period analyzed a high reduction in costs and LOS in the majority of the analyzed case groups were found.

Application of spatio-temporal filtering to fetal electrocardiogram enhancement.

In this paper we propose a new structure of the instrumentation for electrocardiographic fetal monitoring. We apply a single-channel approach to maternal electrocardiogram suppression in the recorded four abdominal bioelectric signals. Then we exploit spatial and temporal properties of the extracted four-channel fetal electrocardiogram to construct a new channel with higher signal-to-noise ratio. Finally, we perform detection of fetal QRS complexes. The proposed approach is investigated with the help of the constructed database of the maternal abdominal signals. During the detection tests, the spatio-temporal filtering allowed us to decrease significantly the number of the detection errors of different detectors applied. Moreover, we present visually that even if the fetal QRS complexes are buried in noise, the spatio-temporal filtering can produce the signal with the discernible ones.

Towards noise immune detection of fetal QRS complexes.

The noninvasive fetal electrocardiography is a source of more precise information on the fetal heart activity than the measurements based on Doppler ultrasound signals. However, the clinical diagnostic applications of this technique are limited by difficulty with successful detection of small amplitude fetal QRS complexes. In this study, we investigate the influence of different stages of fetal signals processing on the detection performance. The main propositions of the paper are: application of normalized matched filtering to fetal QRS complexes enhancement and a new approach to the final detection of the complexes. Compared to the classical detectors, the proposed new one allows a significant increase of the detection performance for signals of very different quality.

Robust projective filtering of time-warped ECG beats.

In this paper a new version, more immune to noise, of the nonlinear projective filtering is presented. The method employs an algorithm of robust principal component analysis to signal subspaces construction and as a result it achieves high performance in real electromyographic noise environment. Two aspects of the method's action are investigated: its ability to suppress noise and its influence on the precision of the QT interval measurement. Then the method influence on evaluation of the beat-to-beat variability of the repolarization duration is presented. A comparison to the previous versions of the nonlinear projective filtering and to the classical linear one is carried out.

Projective filtering of time warped ECG beats.

The paper proposes a modification of the nonlinear state-space projections (NSSP) method. Our approach, when applied to ECG signal processing, considerably improves the method's performance. One of the crucial operations in NSSP is the search for neighborhoods of the state-space trajectory points. The modification proposed is based on imposing a few restrictions on the time location of the neighborhood points. Dynamic time warping, a technique which allows for nonlinear alignment of time series or sequences of vectors, is applied as a straightforward solution to the task of neighborhoods determination with the restrictions imposed. The influence of nonlinear alignment on the distributions of the determined neighborhoods is presented, and the resulting method of ECG enhancement is investigated.

Cost-sharing strategies combining targeted public subsidies with private-sector delivery achieve high bednet coverage and reduced malaria transmission in Kilombero Valley, southern Tanzania.

BACKGROUND: Cost-sharing schemes incorporating modest targeted subsidies have promoted insecticide-treated nets (ITNs) for malaria prevention in the Kilombero Valley, southern Tanzania, since 1996. Here we evaluate resulting changes in bednet coverage and malaria transmission. METHODS: Bednets were sold through local agents at fixed prices representing a 34% subsidy relative to full delivery cost. A further targeted subsidy of 15% was provided to vulnerable groups through discount vouchers delivered through antenatal clinics and regular immunizations. Continuous entomological surveys (2,376 trap nights) were conducted from October 2001 to September 2003 in 25 randomly-selected population clusters of a demographic surveillance system which monitored net coverage. RESULTS: Mean net usage of 75% (11,982/16,086) across all age groups was achieved but now-obsolete technologies available at the time resulted in low insecticide treatment rates. Malaria transmission remained intense but was substantially reduced: Compared with an exceptionally high historical mean EIR of 1481, even non-users of nets were protected (EIR [fold reduction] = 349 infectious bites per person per year [x4]), while the average resident (244 [x6]), users of typical nets (210 [x7]) and users of insecticidal nets (105 [x14]) enjoyed increasing benefits. CONCLUSION: Despite low net treatment levels, community-level protection was equivalent to the personal protection of an ITN. Greater gains for net users and non-users are predicted if more expensive long-lasting ITN technologies can be similarly promoted with correspondingly augmented subsidies. Cost sharing strategies represent an important option for national programmes lacking adequate financing to fully subsidize comprehensive ITN coverage.

Projective filtering of time-aligned ECG beats for repolarization duration measurement.

Automatic measurement of ventricular repolarization duration is difficult and highly prone to errors. We propose to mitigate this problem by applying projective filtering to enhance the ECG signal prior to measurements. Our method performs time-alignment of ECG beats and then employs the rules of principal component analysis to the desired ECG reconstruction. As a result, significant noise reduction is obtained while distortions of the desired ECG components remain negligible. The proposed method is presented under white noise conditions; the influence on the precision of repolarization duration measurement is then investigated. Finally, the method's influence on evaluation of repolarization duration variability when the analyzed signals are contaminated with real electromyographic noise is discussed.

Sequential chemo-radiotherapy in non-small cell lung cancer.

Locally advanced non-small cell lung cancer (NSCLC) stage IIIA/IIIB represents approximately 30% of NSCLC and still has a poor prognosis. In this article we give a short review on several randomized phase III trials that showed a slight but significant survival benefit for sequential chemo-radiotherapy in the treatment of locally advanced NSCLC.