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Summary Hereditary vitreoretinopathies (VRPs), traditionally divided into the groups of exudative and degenerative VRPs, encompass a number of diseases affecting the vitreous and the retina. These disorders are the commonest cause of inherited retinal detachment with high risk of vision loss during infancy. We designed a next generation sequencing (NGS) assay including ATOH7, COL2A1, COL9A1, COL9A2, COL9A3, COL11A1, COL18A1, FZD4, KCNJ13, KIF11, LOXL3, LRP5, NDP, TSPAN12, VCAN and ZNF408 allowing an exhaustive genetic screening with the most frequently mutated genes reported to be associated with all inherited VRPs. The diagnostic performance of this new design was evaluated on a cohort of 166 probands with a suspected clinical diagnosis of exudative or degenerative VRPs comprising 47% of children under 15 years old. We identified a large spectrum of causative mutations (single nucleotide changes as well as copy number variants) diagnosing molecular defects for 60% of the patients. Our NGS panel is therefore a promising screening method to be used efficiently in routine practice, able to detect a higher number of molecular defects than Sanger sequencing, improving significantly the molecular diagnosis of inherited VRPs.

Purpose Optic neuropathy (ON) is one of the complications of alcohol. The aim of this study was to assess the prevalence of alcoholic ON in a cohort of patients hospitalized for alcohol withdrawal. Secondary objective was to explore the predictive value of optic nerve changes for diagnosis of ON. Methods This was a single-center prospective study. A complete eye examination was performed during the patient's alcohol withdrawal. The definition of alcoholic ON used was an assocation of alterations of visual field with impaired color vision. Optic nerve function and morphology were assessed using visual evoked potentials, optical coherence tomography (OCT), Nerve Fiber Indicator from polarimetry (GDx) and Moorfields Regression Analysis of the Heidelberg Retina Tomograph II (MRA-HRT II). Results Two hundred patients were included prospectively from January 2010 to June 2013 (145 men and 55 women) with a mean age of 47 ± 12 year. The average alcohol consumption was 220 ± 122 g/day. 46 patients (23%) responded to alcoholic ON defintion (13.5 % in both eyes and 9.5% in only one eye). Diagnostic sensitivity and specificity for visual evoked potentials were of 55.5% and 54.5% respectively; for GDx 18% and 97%, respectively; for OCT 38% and 92%, respectively; and for MRA-HRT II 19% and 79%, respectively. Conclusion A high prevalence of alcoholic ON observed in this study should prompt screening and early treatment. From predictive value of objective optic nerve changes, we discuss the best couple of exams to complete the screening of alcoholic ON.

Au contact du patient la barrette ultrasonore est, sous ses differentes formes, le prolongement de la main du praticien dans cette operation de palpation visuelle qu'est l'echographie. L'echographiste devient familier de l'ergonomie de sa sonde et des images qu'elle lui permet d'aller chercher. Mais encore, si l'on observe la structure interne de ces barrettes : qu'elles soient courbes, endoscopiques ou a deflexion electronique, on decouvre qu'elles sont le lieu d'une formidable integration technologique constamment renouvelee grâce au fort niveau de competition qui existe sur ce marche. La qualite des Images, le niveau des artefacts dependent directement des distributions spatiale et temporelle de l'energie des faisceaux ultrasonores. Cela devra etre traduit en termes de specifications precises pour le fonctionnement de chacun des transducteurs qui composent la barrette, pour l'homogeneite de l'ensemble et le couplage entre elements. On montrera les differentes etapes que comporte la fabrication de cet objet : simulations calculees des rayonnements dans le temps et dans l'espace, choix et mise en oeuvre des materiaux piezoelectriques et passifs, decoupes, connexions et câblage mise en place des boitiers. Cet expose montrera aussi comment sont integres le respect des normes de securite electrique et acoustique de qualite les contraintes en termes de fiabilite et de sterilisation. Prenez soin de ces objets familiers que sont les sondes: il y a beaucoup de savoir-faire a l'interieur.

Lead-based piezoelectric single crystals such as PZN-PT and PMN-PT have been first developed for under water applications by the U.S. Navy. Their outstanding piezoelectric properties (d33 as high as 2000pC/N and k33 ≫ 90%) make them valuable for high-end ultrasound transducers. Thus, they have been successfully used and commercialized in medical field mainly for cardiac imaging (2–5MHz) but manufacturing such a probe is critical since single crystal structures are more sensitive to thermal and mechanical stresses induced by standard micromachining process.

Both medical and industrial fields require ultrasound transducers able to withstand high temperature (>100degC) and harsh environment (high pressure, chemical resistance). Such probes can be used as sterilizable equipment by autoclave for the medical applications and can perform in-situ characterization of materials and in-service inspection in non-destructive testing (NDT) applications. This article will focus on the development of specific 1-3 piezocomposite configurations to address these applications in the 5-8 MHz frequency range (single element and array transducers). Adequate piezocomposite configurations are integrated into complete transducer. The electro-acoustical performances will be reported after more from 20 to 85 sterilization cycles. For NDT applications, the transducers will be characterized at high temperatures up to 110degC

The range of applications demanding the development of high frequency ultrasound imaging is very broad, from dermatology and ophthalmology to intravascular and small animals imaging, to improve the resolution of the images over a small penetration depth. However the manufacture of such imaging systems remains very challenging from both transducer manufacture (small dimensions of the elements, thin layers materials properties control) and associated electronic system perspectives. This article extends the current state of the art limited at 20 MHz for fully operational array devices and presents the acoustical design, manufacture and evaluation of a 128 elements 30 MHz ultrasound array based on the 1-3 piezocomposite technology, with a 100 /spl mu/m pitch and a 2 mm elevation aperture. Electro-acoustical characterisation of the full array is reported (in terms of bandwidth, pulse duration and homogeneity performance) as well as electrical characterisation (impedance and cross-coupling measurements).

In non-destructive testing (NDT) applications, ultrasound transducer arrays capable of withstanding high temperatures and harsh environment (high pressure, chemical resistance) are required to perform the in-situ characterisation of materials, process monitoring and in-service inspection.

Lead-based piezoelectric single crystals such as Pb(Zn/sub 1/3/Nb/sub 2/3/)O/sub 3/-PbTiO/sub 3/ (PZN-PT) and Pb(Mg/sub 1/3/Nb/sub 2/3/)O/sub 3/-PbTiO/sub 3/ (PMN-PT) have been extensively studied during the last years as their outstanding piezoelectric properties (d/sub 33/ as high as 2000pC/N and k/sub 33/ > 90%) make them valuable for high-end ultrasound transducers. Nevertheless the specific nature of these materials, as compared with standard piezoceramics, requires to develop new transducer micro-machining and manufacturing processes to enhance the final properties of the transducers and to improve both sensitivity and bandwidth of these probes. This paper presents the acoustical design, fabrication and evaluation of a 64 elements ultrasound phased array for transoesophagial probe based on single crystal materials. The achieved phased array is a 5MHz configuration with a circular aperture. The whole transducer is included within diameter 10mm and 2mm height. Acoustical design and final results will show the improvements achieved with single crystals for this configuration by comparing these results to those obtained on standard piezoceramic phased array. Electro-acoustic characterisation is performed on the whole array and homogeneity performances will also be presented.

Multi-elements ultrasound probes are now used in the industrial Non Destructive Testing to replace single element probes in targeted applications to improve quality, reproducibility and speed of control. The complexity of the parts to be controlled requires the development of specific ultrasound probes, from complex geometries linear arrays (concave or conical shapes) to 2D matrix arrays. This poster presents the acoustical design and manufacture of a 2D conical ultrasound array for fastener hole inspection. This complex probe includes 504 rectangular elements, with dimensions 0.3 mm/spl times/ 0.4 mm at 10 MHz center frequency, that are laid out on a conical surface. The poster reviews also the electro-acoustic characterisation performed on the full array, including frequency, bandwidth and homogeneity performances. This conical 2D-array is finally integrated in a probe housing, interconnected and interfaced to an ultrasound system.

Over the last decade, ultrasound imaging has been successfully demonstrated at 20 MHz and above using single elements transducer. High frequency arrays are only commercially available below 20 MHz and arrays with higher frequencies are still at the research stage. However, a 20 MHz center frequency exhibits a very interesting trade-off between sensitivity or penetration and expected image resolution. This paper presents the acoustical design, fabrication and evaluation of a 128 elements ultrasound array based on piezo-composite technology, with a 210 /spl mu/m pitch and a 3 mm elevation aperture. Electro-acoustic characterization is performed on the full array and an average center frequency of 20 MHz is achieved as well as state of the art homogeneity characteristics. Bandwidth, insertion loss results, directivity measurement and cross coupling performance are disclosed. The transducer array is subsequently integrated in a probe housing, interconnected and interfaced to an ultrasound system. Finally, images covering various applications are presented and discussed from a clinical perspective.