Visual loss and presumed pseudoxanthoma elasticum confirmed with genetic analysis but not with skin examination and biopsies

Objective: Case report of a patient with angioid streaks, peau d'orange, comet tail lesions, choroidal neovascularisation and presumed pseudoxanthoma elasticum (PXE). PXE was confirmed by gene analysis but not by skin biopsies. Methods: Case report of a patient with angioid streaks identified at age 21 and follow-up till age 43 with repeated fluorescein angiography (FA) and optical coherence tomography (OCT). Dermatologic examination, skin biopsies and genetical analysis performed to confirm suspected diagnosis of PXE. Results: At age 43, no specific skin lesions were identified and 3 biopsies could not confirm PXE. Genetic analysis showed a homozygous mutation in the ABCC6 gene and confirmed the diagnosis of PXE. Conclusions: This case illustrates that in patients with angioid streaks having strong ocular indicators of PXE, confirmation of PXE can be obtained not only with dermatologic examination and skin biopsies, but also with genetic analysis. PXE associated mutations can be detected occasionally in biopsy negative patients and for this reason are extremely helpful in confirming a suspected diagnosis

Plasmonic Stripes in Aqueous Environment Co-Integrated With Si3N4 Photonics

International audienceWe demonstrate the design, fabrication, and the experimental characterization of gold-based plasmonic stripes butt-coupled with low-pressure-chemical-vapor-deposition (LPCVD)-based Si 3 N 4 waveguides for the excitation of surface-plasmon-polariton (SPP) modes in aqueous environment. Plasmonic gold stripes, in aqueous environment, with cross-sectional dimensions of 100 nm × 7 μm were interfaced with 360 nm × 800 nm Si 3 N 4 waveguides cladded with low-temperature-oxide, exploiting linear photonic tapers with appropriate vertical (VO) and longitudinal (LO) offsets between the plasmonic and photonic waveguide facets. An interface insertion loss of 2.3 ± 0.3 dB and a plasmonic propagation length (L spp) of 75 μm have been experimentally measured at 1.55 μm for a VO of 400 nm and an LO of 500 nm, with simulation results suggesting high tolerance to VO and LO misalignment errors. The proposed integration approach enables seamless co-integration of plasmonic stripes, in aqueous environment, with a low-loss and low-cost LPCVD-based Si 3 N 4 waveguide platform, revealing its strong potential for future employment in biochemical sensing applications

Water Cladded Plasmonic Slot Waveguide Vertically Coupled With Si 3 N 4 Photonics

International audienc

Media 1: Electro-optic light modulation and THz generation in locally plasma-activated silicon nanophotonic devices

Originally published in Optics Express on 10 March 2014 (oe-22-5-5252

50 GBit/s Photodetectors Based on Wafer-Scale Graphene for Integrated Silicon Photonic Communication Systems

Optical data links are the backbone of today’s telecommunication infrastructure. The integration of electronic and optic components on one chip is one of the most attractive routes to further increase the system performance. Here, we present the fabrication of photodetectors based on CVD-grown graphene on silicon photonic waveguides. The devices operate bias-free in the C-band at 1550 nm and show an extrinsic −3 dB bandwidth of 41 GHz. We demonstrate that these detectors work at data rates up to 50 GBit/s with excellent signal integrity