Performance-based financing as a health system reform : mapping the key dimensions for monitoring and evaluation

Peer reviewedPublisher PD

Adherence to self-administered tuberculosis treatment in a high HIV-prevalence setting: a cross-sectional survey in Homa Bay, Kenya.

Good adherence to treatment is crucial to control tuberculosis (TB). Efficiency and feasibility of directly observed therapy (DOT) under routine program conditions have been questioned. As an alternative, Médecins sans Frontières introduced self-administered therapy (SAT) in several TB programs. We aimed to measure adherence to TB treatment among patients receiving TB chemotherapy with fixed dose combination (FDC) under SAT at the Homa Bay district hospital (Kenya). A second objective was to compare the adherence agreement between different assessment tools

Fast Euclidean morphological operators using local distance transformation by propagation

We propose a new method to compute the morphological dilation of a binary image with a circular structuring element of any given size, on a discrete lattice. The algorithm is equivalent to applying a threshold on an exact Euclidean distance map, but computations are restricted to a minimum number of pixels. The complexity of this dilation algorithm is compared to the complexity of the commonly used approximation of circular structuring elements and found to have a similar cost, while providing better results

Fast and exact signed Euclidean distance transformation with linear complexity

We propose a new signed or unsigned Euclidean distance transformation algorithm, based on the local corrections of the well-known 4SED algorithm of Danielsson. Those corrections are only applied to a small neighborhood of a small subset of pixels from the image, which keeps the cost of the operation low. In contrast with all fast algorithms previously published, our algorithm produces perfect Euclidean distance maps in a time linearly proportional to the number of pixels in the image. The computational cost is close to the cost of the 4SSED approximation

Toward a content-based watermarking scheme

Image watermarking consists in embedding an unnoticeable and indelible mark inside a digital image. Watermarking technologies aims at solving copyright and integrity problems. Nevertheless classical geometrical transforms generally induce a loss of synchronization that prevent the detection of the mark. We propose in this paper a content-based watermarking scheme that uses a feature point detector to link the mark with the content of the image. In this scheme, feature point detection is followed by a triangular tessellation and the signature is embedded in each triangle of the partition. Our results show that the presented scheme is robust to local geometrical transforms and attacks such as Stirmark.Le tatouage d'images consiste à insérer une signature invisible et indélébile dans une image. Il permet de répondre à des problèmes de droit d'auteur ou d'intégrité. Les transformations géométriques peuvent cependant provoquer une perte de synchronisation et ainsi empêcher la détection de la signature. Nous proposons une méthode de tatouage fondée sur le contenu qui utilise un détecteur de points d'intérêts pour lier la signature au contenu de l'image. La détection de point d'intérêts permet de créer une partition triangulaire et la signature est ensuite insérée dans chacun des triangles. Nos résultats montrent que la méthode présentée est robuste aux déformations géométriques tels que Stirmark

Atlas-based segmentation of the brain for 3-dimensional treatment planning in children with infratentorial ependymoma

This paper presents a fully automated brain segmentation method that has been applied to a group of patients with infratentorial ependymoma. The purpose of the study was to test the hypothesis that fully-automated atlas-based segmentation methods provide useful normal tissue dosimetry from which dose-volume modeling may be performed in a manner equivalent to dose-volume data obtained from manual contouring. To test this hypothesis, we compared the integrated average dose for three small (chiasm, pituitary, hypothalamus) and three large (temporal lobes and total brain) normal tissue structures from ten patients using automated and manual contouring. There was no significant difference in the calculated average dose for the structures of interest. The greatest difference was noted for smaller structures which were located along the midline and in the gradient of dose. The results of this study form the basis of an ongoing larger study involving similar patients to evaluate automated and manual contouring as well as the clinical significance of any differences using dose-volume modeling