Depth and Size Limits for the Visibility of Veins Using the VeinViewer Imaging System

Administration of fluids or medication and blood draw procedures require the nurse or the phlebotomist to access the veins in patients at hospitals or phlebotomy centers. It is important to minimize the discomfort associated with sticking needles in the patient more than once and most often, necessary to find an appropriate vein within few minutes. However, problems involved in accessing veins in pediatric and obese patients make it very difficult to perform a successful stick in a short time. The VeinViewer Imaging System is an infrared imaging device that provides the nurses and phlebotomists a means for locating veins in the very first attempt and within a few seconds. A camera captures an image of the veins illuminated by infrared light and a contrast-enhanced image of the veins is projected back onto the patient’s skin in real-time using a projector, after being processed by a computer. Each vein in the VeinViewer image appears with different contrast against the background skin. To evaluate the performance of the device, a thorough investigation of the properties of the vein affecting its contrast can be of immense value. The goal of this research is to determine quantitatively the effect of physical properties of veins such as depth and diameter on its visibility in the VeinViewer image. The results of this study can be interpreted to understand the biological phenomena influencing the quality of the VeinViewer image. An extension of this study may lead to advancement in the hardware or software which potentially will benefit the phlebotomists and physicians

An extended finite difference method for singular perturbation problems on a non-uniform mesh

An extended second order finite difference method on a variable mesh is proposed for the solution of a singularly perturbed boundary value problem. A discrete equation is achieved on the non uniform mesh by extending the first and second order derivatives to the higher order finite differences. This equation is solved efficiently using a tridiagonal solver. The proposed method is analysed for convergence, and second order convergence is derived. Model examples are solved by the proposed scheme and compared with available methods in the literature to uphold the method

Formulation and Evaluation of Lignocaine Hydrochloride Proniosomes Loaded Orabase for Dental Anaesthesia

The aim of this research is to prepare and evaluate lignocaine HCl Proniosomal orabase for enhanced permeation and prolonged dental anaesthesia effect. Objective: Various lignocaine proniosomal gels were formulated employing various surfactants. Methods: The formulations were scrutinized for entrapment efficiency, optical microscopy, in-vitro diffusion and release studies, mucoadhesive strength, ex-vivo permeation studies and drug – excipient interactions were determined by FTIR spectroscopy. Results: span 80 was found to be superior and significant for loading in to orabase. Considering the best entrapment efficiency with span 80 (91.60%) and optimum vesicle shape, along with prolonged drug permeation (33.6% for 24 h) the formulation F4 was selected and optimized for loading into orabase. The formulation F4 loaded orabase exhibited significant prolonged release over 10 h, and permeation profiles exhibited nearly two – fold increased flux in comparison with control. Good mucoadhesive strength was observed for proniosomal orabase 6273dynes/cm2, No evidence of incompatibility amongst formulation components from FTIR studies. SEM images revealed the particle size range from 50 μmt to 100 μmt for proniosomal orabase. Conclusion: Orabase can be an effective carrier for proniosomes with enhanced retention time at the site of application and provide prolonged release for oro-dental conditions. Keywords: lignocaine Hcl, Oro-dental anaesthesia, Proniosomal gel, Orabase, Entrapment efficiency, prolonged release