Consensus statement on indications for anti-angiogenic therapy in the management of corneal diseases associated with neovascularisation: outcome of an expert roundtable

The cornea is the clear window at the front of the eye and is the eye's main refractive medium. Its transparency is essential for vision. Corneal neovascularisation is a common clinical problem with serious consequences for vision; it can compromise corneal transparency and plays a major role in corneal graft rejection by breaching corneal immune privilege. In this review, we formulate a consensus on the unmet medical needs in the management of corneal neovascularisation and outline a framework for the clinical research that is needed to identify suitable agents to meet these needs.     

Using longitudinal data from a clinical trial in depression to assess the reliability of its outcome scales

Longitudinal studies are permeating clinical trials in psychiatry. Additionally, in the same field, rating scales are frequently used to evaluate the status of the patients and the efficacy of new therapeutic procedures. Therefore, it is of utmost importance to study the psychometric properties of these instruments within a longitudinal framework. In the area of depression, the Hamilton depression rating scale (HAMD) is regularly used for antidepressant treatment evaluation. However, the use of HAMD has not been exempted from criticism what has lead to the development of new scales that are expected to be more sensitive for change, such as the Montgomery-Åsberg depression rating scale (MADRS). In general, the reliability of these scales has been extensively studied by using classical methods for reliability estimation, developed for specifically designed reliability studies. Unfortunately, the settings customarily considered in these reliability studies are usually far from the practical conditions in which these scales are applied in clinical trials and practice. In the present paper, we assess the reliability of these instruments in a more realistic scenario thereby using longitudinal data coming from clinical studies. Nowadays, newly developed methodology based on an extended concept of reliability, allows us to use longitudinal data for reliability estimation. This new approach not only enables to avoid bias by offering a better control of disturbing factors but it also produces more precise estimates by taking advantage of the large sample taking sizes available in clinical trials. Further, it offers practical guidelines for an optimal use of a rating scale in order to achieve a particular level of reliability. The merits of this new approach are illustrated by applying it on two clinical trials in depression to assess the reliability of the three outcome scales, HAMD, MADRS, and the Hamilton anxiety rating scale (HAMA).     

Analytical determination of stress patterns in the periodontal ligament during orthodontic tooth movement

A dedicated software package that allows simulation of tooth movement can lead to shortening of the treatment program in orthodontics. A first step in the development of this software is the modelling of the movement of a single tooth. Forces applied to the crown of the tooth are transmitted to the alveolar bone through the periodontal ligament, stretching, and compressing the ligament, eventually resulting in tooth movement. This paper presents an analytical model that predicts stresses and strains inside this ligament by approximating the shape of the root as an elliptic paraboloid. The model input consists of 2 material parameters and 4 geometrical parameters. To assess the accuracy of the model a finite element model (FEM) was constructed to compare the results and the influence of the eccentricity of the root was studied. The results show that the model is able to successfully describe the global behavior of the PDL and, except at a region near the alveolar crest, the differences between analytical and FEM results are small. In contrast to FEM, the analytical model does not require setting up a 3D-model and creating a mesh, allowing for significantly lower computational times and reducing cost when implementing in clinical practice.     

Age-related prevalence rates of sexual difficulties,sexual dysfunctions and sexual distress in heterosexual men: results from an online survey in Flanders

Abstract

Besides erectile difficulties, age-related prevalence rates of male sexual difficulties remain inconsistent. Moreover, apart from erectile and premature ejaculation, epidemiological studies that provide detailed age-related prevalence rates of other sexual difficulties (e.g. lack of sexual desire) in men are rare. Prevalence rates of sexual dysfunctions (i.e. sexual difficulties that cause personal distress) are almost non-existent. Based on an online study of 14,836 heterosexual Flemish men aged 16–74 years, age-related prevalence of sexual difficulties, sexual dysfunctions and associations with personal sexual distress are presented. While most sexual difficulties increased from age 55 to 60, hyperactive sexual desire and premature ejaculation decreased with age. Compared to sexual difficulties, sexual dysfunctions displayed only a mild association with age, suggesting that sexual difficulties per se and sexual distress are differently associated with age. The current results imply that research on predictors of sexual dysfunctions could benefit from assessing protective and risk factors associated with sexual difficulties and those associated with sexual distress separately.