[Creation of a complete organised care network allowing facilitated access to ophthalmological care for patients living in socially "at-risk" situations, feasibility study]. / Mise en place d'un réseau de prise en charge facilitant l'accès aux soins ophtalmologiques des patients vivant en situation de précarité, étude de faisabilité.

BACKGROUND: Currently, renouncement to healthcare by socially "at-risk" patients continues to increase and access to ophthalmological care is complex. The main objective of this study is to test the feasibility of a complete organised care network allowing facilitated access to ophthalmological care for patients living in socially "at-risk" situations. METHOD: A prospective interventional study was conducted within four social housing infrastructures to screen for vision problems in the "at-risk" socially population in question. Partnering with the ophthalmological department of the CHRU de Nancy, an interventional and supportive care trial for the affected population was conducted with the assistance of social workers, nursing aides, opticians, and the author. RESULTS: Ten screening sessions were conducted between December 2015 and April 2016 allowing a vision exam of sixty-five patients living in social housing. Twenty-five patients benefited from specialised care within a three-month time frame provided by the ophthalmological department, of which nineteen patients received corrective lenses. The remaining six patients received other types of ophthalmological care. CONCLUSION: The study allowed to demonstrate that the cooperation of willing actors makes it possible to improve access to visual healthcare for patients living in socially "at-risk" situations, in particular in the frame of ophthalmological care, often taking second place in a general medical consultation.

Angle-dependence and reproducibility of dual-beam vector doppler ultrasound in the common carotid arteries of normal volunteers.

Dual-beam vector Doppler has the potential to improve peak systolic blood velocity measurement accuracy by automatically correcting for the beam-flow Doppler angle. Using a modified linear-array system with a split receive aperture, we have assessed the angle-dependence over Doppler angles of 40 degrees -70 degrees and the reproducibility of the dual-beam blood maximum velocity estimate measured in the common carotid arteries (CCA) 1 to 2 cm prior to the bifurcation of 9 presumed-healthy volunteers. The velocity magnitude estimate was reduced by approximately 7.9% as the angle between the transmit beam and the vessel axis was increased from 40 degrees to 70 degrees. With repeat measurements made, on average, approximately 6 weeks apart, the 95% velocity magnitude limits of agreement were as follows: Intraobserver -41.3 to +45.2 cm/s; interobserver -29.6 to +46.8 cm/s. There was an 8.6 cm/s interobserver bias in velocity magnitude. We conclude that the dual-beam vector Doppler system can measure blood velocity within its scan plane with low dependence on angle and with similar reproducibility to that of single-beam systems.

An in vitro system for the study of ultrasound contrast agents using a commercial imaging system.

An in vitro system for the investigation of the behaviour of contrast microbubbles in an ultrasound field, that provides a full diagnostic range of settings, is yet to be presented in the literature. The evaluation of a good compromise of such a system is presented in this paper. It is based on (a) an HD13000 ATL scanner (Bothell, WA, USA) externally controlled by a PC and (b) on the use of well-defined reference materials. The suspensions of the reference ultrasonic scattering material are placed in an anechoic tank. The pulse length ranges from 2 to 10 cycles, the acoustic pressure from 0.08 to 1.8 MPa, the transmit frequency from 1 to 4.3 MHz, and the receive frequency from 1 to 8 MHz. The collection of 256 samples of RF data, at an offset distance from the transducer face, was performed at 20 MHz digitization rate, which corresponds to approximately 1 cm depth in water. Two particle suspensions are also presented for use as reference scatterers for contrast studies: (a) a suspension of Orgasol (ELF Atochem, Paris, France) particles (approximately 5 microm mean diameter) and (b) a suspension of Eccosphere (New Metals & Chemicals Ltd, Essex, UK) particles (approximately 50 microm mean diameter). A preliminary experiment with the contrast agent Definity (DuPont Pharmaceutical Co, Waltham, MA) showed that the above two materials are suitable for use as a reference for contrast backscatter.