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International audience; Background: Intravascular ultrasound (IVUS)-guided PCI improves the prognosis of left main stem (LMS) PCI and is currently recommended by international guidelines. Although OCT resolution is greater than that of IVUS, this tool is not yet recommended in LMS angioplasty due to the absence of data.Aims: This pilot study aimed to analyse the feasibility, safety and impact of OCT-guided LMS PCI.Methods: This prospective, multicentre trial investigated whether patients might benefit from OCT-guided PCI for mid/distal LMS according to a pre-specified protocol. The primary endpoint was procedural success defined as follows: residual angiographic stenosis

Purpose: to assess correlation between visual acuity (VA) and macular flow density (MFD) in young type 1 diabetic patients with florid diabetic retinopathy (FDR) Methods: a retrospective observational case study of thirty-eight eyes of 26 patients without lens opacity, intravitreal hemorrhage or history of diabetic macular edema, who underwent panretinal photocoagulation for FDR. Control group comprised 14 eyes of 7 age-matched healthy subjects with normal VA. MFD (%) in the superficial (SVP) and deep (DCP) capillary plexuses were measured with Optical Coherence Tomography Angiography (OCT-A) and OCT B-scans were qualitatively analyzed. Results: based on visual acuity (VA), eyes were divided into two groups: “normal VA” with logMAR VA = 0 (n=22) and “decreased VA” with logMAR VA > 0 (n=16). MFD was lower in the decreased VA group than in the normal VA group in the SVP (P 0 (n = 16). La DCM était plus faible dans le groupe AV diminuée que dans le groupe AV normale dans le SVP (P

Purpose: To evaluate differences in the visual phenotype and natural history of Usher syndrome caused by mutations in MYO7A or USH2A, the most commonly affected genes of Usher syndrome Type I (USH1) and Type II (USH2), respectively.Methods: Eighty-eight patients with a clinical diagnosis of USH1 (26 patients) or USH2 (62 patients) were retrospectively evaluated. Of these, 48 patients had 2 disease-causing mutations in MYO7A (10 USH1 patients), USH2A (33 USH2 patients), and other USH (5 patients) genes. Clinical investigation included best-corrected visual acuity, Goldmann visual field, fundus photography, electroretinography, and audiologic and vestibular assessments. Longitudinal analysis was performed over a median follow-up time of 3.5 years.Results: Patients carrying mutations in MYO7A had a younger age of onset of hearing and visual impairments than those carrying mutations in USH2A, leading to an earlier diagnosis of the disease in the former patients. Longitudinal analysis showed that visual acuity and visual field decreased more rapidly in subjects carrying MYO7A mutations than in those carrying USH2A mutations (mean annual exponential rates of decline of 3.92 vs. 3.44% and of 8.52 vs. 4.97%, respectively), and the former patients reached legal blindness on average 15 years earlier than the latter.Conclusion: The current study confirmed a more severe progression of the retinal disease in USH1 patients rather than in USH2 patients. Furthermore, most visual symptoms (i.e., night blindness, visual acuity worsening) occurred at an earlier age in USH1 patients carrying mutations in MYO7A. Purpose: To evaluate differences in the visual phenotype and natural history of Usher syndrome caused by mutations in MYO7A or USH2A, the most commonly affected genes of Usher syndrome Type I (USH1) and Type II (USH2), respectively. Methods: Eighty-eight patients with a clinical diagnosis of USH1 (26 patients) or USH2 (62 patients) were retrospectively evaluated. Of these, 48 patients had 2 disease-causing mutations in MYO7A (10 USH1 patients), USH2A (33 USH2 patients), and other USH (5 patients) genes. Clinical investigation included best-corrected visual acuity, Goldmann visual field, fundus photography, electroretinography, and audiologic and vestibular assessments. Longitudinal analysis was performed over a median follow-up time of 3.5 years. Results: Patients carrying mutations in MYO7A had a younger age of onset of hearing and visual impairments than those carrying mutations in USH2A, leading to an earlier diagnosis of the disease in the former patients. Longitudinal analysis showed that visual acuity and visual field decreased more rapidly in subjects carrying MYO7A mutations than in those carrying USH2A mutations (mean annual exponential rates of decline of 3.92 vs. 3.44% and of 8.52 vs. 4.97%, respectively), and the former patients reached legal blindness on average 15 years earlier than the latter. Conclusion: The current study confirmed a more severe progression of the retinal disease in USH1 patients rather than in USH2 patients. Furthermore, most visual symptoms (i.e., night blindness, visual acuity worsening) occurred at an earlier age in USH1 patients carrying mutations in MYO7A.

The membrane-associated palmitoylated protein 5 (MPP5 or PALS1) is thought to organize intracellular PALS1-CRB-MUPP1 protein scaffolds in the retina that are involved in maintenance of photoreceptor–Müller glia cell adhesion. In humans, the Crumbs homolog 1 (CRB1) gene is mutated in progressive types of autosomal recessive retinitis pigmentosa and Leber congenital amaurosis. However, there is no clear genotype–phenotype correlation forCRB1mutations, which suggests that other components of the CRB complex may influence the severity of retinal disease. Therefore, to understand the physiological role of the Crumbs complex proteins, especially PALS1, we generated and analyzed conditional knockdown mice forPals1. Small irregularly shaped spots were detected throughout the PALS1 deficient retina by confocal scanning laser ophthalmoscopy and spectral domain optical coherence tomography. The electroretinography a- and b-wave was severely attenuated in the aged mutant retinas, suggesting progressive degeneration of photoreceptors. The histological analysis showed abnormal retinal pigment epithelium structure, ectopic photoreceptor nuclei in the subretinal space, an irregular outer limiting membrane, half rosettes of photoreceptors in the outer plexiform layer, and a thinner photoreceptor synaptic layer suggesting improper photoreceptor cell layering during retinal development. The PALS1 deficient retinas showed reduced levels of Crumbs complex proteins adjacent to adherens junctions, upregulation of glial fibrillary acidic protein indicative of gliosis, and persisting programmed cell death after retinal maturation. The phenotype suggests important functions of PALS1 in the retinal pigment epithelium in addition to the neural retina.

International audience; In humans, the Crumbs homolog-1 (CRB1) gene is mutated in progressive types of autosomal recessive retinitis pigmentosa and Leber congenital amaurosis. However, there is no clear genotype-phenotype correlation for CRB1 mutations, which suggests that other components of the CRB complex may influence the severity of retinal disease. Therefore, to understand the physiological role of the Crumbs complex proteins, we generated and analysed conditional knockout mice lacking CRB2 in the developing retina. Progressive disorganization was detected during late retinal development. Progressive thinning of the photoreceptor layer and sites of cellular mislocalization was detected throughout the CRB2-deficient retina by confocal scanning laser ophthalmoscopy and spectral domain optical coherence tomography. Under scotopic conditions using electroretinography, the attenuation of the a-wave was relatively stronger than that of the b-wave, suggesting progressive degeneration of photoreceptors in adult animals. Histological analysis of newborn mice showed abnormal lamination of immature rod photoreceptors and disruption of adherens junctions between photoreceptors, Müller glia and progenitor cells. The number of late-born progenitor cells, rod photoreceptors and Müller glia cells was increased, concomitant with programmed cell death of rod photoreceptors. The data suggest an essential role for CRB2 in proper lamination of the photoreceptor layer and suppression of proliferation of late-born retinal progenitor cells.

International audience; Glial cells release molecules that influence brain development, function, and disease. Calcium-dependent exocytosis has been proposed as potential release mechanism in astroglia, but the physiological relevance of "gliotransmission" in vivo remains controversial. We focused on the impact of glial exocytosis on sensory transduction in the retina. To this end, we generated transgenic mice to block exocytosis by Cre recombinase-dependent expression of the clostridial botulinum neurotoxin serotype B light chain, which cleaves vesicle-associated membrane protein 1-3. Ubiquitous and neuronal toxin expression caused perinatal lethality and a reduction of synaptic transmission thus validating transgene function. Toxin expression in Müller cells inhibited vesicular glutamate release and impaired glial volume regulation but left retinal histology and visual processing unaffected. Our model to study gliotransmission in vivo reveals specific functions of exocytotic glutamate release in retinal glia.

International audience; INTRODUCTION: Magnetic resonance imaging (MRI) is an excellent imaging modality for soft tissues. Magnetization transfer (MT) imaging is an MRI technique that is sensitive to the bound protons of macromolecules and therefore can aid in the assessment of nerve damage. METHODS: Measurements of the MT ratio (MTR), which provides an index of the MT effects in tissues, were performed in the wrist and foot of 5 volunteers. RESULTS: The MTR of foot (interdigital) nerves (22.2 ± 2.1%) was smaller than that of the median nerve (41.1 ± 1.4%). No difference was observed between MTR in muscles adjacent to foot nerves (46.0 ± 1.5%) and muscles adjacent to the median nerve (44.2 ± 1.9%). CONCLUSIONS: In this study we demonstrate the feasibility of measuring the MTR of foot nerves. The difference of MTR between median and foot nerves indicates a difference in structure/composition. The MTR of peripheral nerves may serve as a biomarker of nerve damage, collagen integrity, and demyelination.

International audience; Myelin sheath disruption is responsible for multiple neuropathies in the central and peripheral nervous system. Myelin imaging has thus become an important diagnosis tool. However, in vivo imaging has been limited to either low-resolution techniques unable to resolve individual fibers or to low-penetration imaging of single fibers, which cannot provide quantitative information about large volumes of tissue, as required for diagnostic purposes. Here, we perform myelin imaging without labeling and at micron-scale resolution with >300-μm penetration depth on living rodents. This was achieved with a prototype [termed deep optical coherence microscopy (deep-OCM)] of a high-numerical aperture infrared full-field optical coherence microscope, which includes aberration correction for the compensation of refractive index mismatch and high-frame-rate interferometric measurements. We were able to measure the density of individual myelinated fibers in the rat cortex over a large volume of gray matter. In the peripheral nervous system, deep-OCM allows, after minor surgery, in situ imaging of single myelinated fibers over a large fraction of the sciatic nerve. This allows quantitative comparison of normal and Krox20 mutant mice, in which myelination in the peripheral nervous system is impaired. This opens promising perspectives for myelin chronic imaging in demyelinating diseases and for minimally invasive medical diagnosis.

International audience; INTRODUCTION: With their ability to migrate into the cornea and release toxins, caterpillar hairs can induce different clinical presentations such as conjunctivitis, keratoconjunctivitis, uveitis, and less frequently vitreoretinal inflammation (hyalitis, papillitis, macular edema). OBSERVATION: We report a case that occurred in Alsace (France) in a 13-years-old boy presenting with keratitis caused by caterpillar hairs. We localized them in the cornea, for the first time, using confocal microscopy and anterior segment spectral optical coherence tomography. CONCLUSION: Confocal microscopy and spectral optical coherence tomography can be useful for diagnosis and follow-up of this disease.

International audience; PURPOSE: To evaluate the role of preoperative macular hole (MH) diameter, cataract surgery, and cystoid macular edema (CME) in the reopening of idiopathic macular hole (IMH) after initially successful surgery. DESIGN: Multicenter, retrospective, comparative case series. METHODS: One hundred and thirty patients (135 eyes) with stage 2, 3, or 4 IMH were included after successful IMH repair at Dijon University Hospital or Nancy University Hospital. The eyes were separated into 4 groups according to the lens status: group 1, vitrectomy in pseudophakic eyes; group 2, vitrectomy and cataract extraction as a combined procedure; group 3, vitrectomy followed by cataract extraction; group 4, vitrectomy on eyes that remained phakic. All patients underwent a complete vitrectomy with retinal inner limiting membrane peeling and intraocular gas tamponade. The main outcome measures were IMH closure rate and best-corrected visual acuity. RESULTS: Mean duration of symptoms was 8.6 +/- 7.6 months. The follow-up was 37 +/- 8.6 months (range, 30 to 67 months). The mean preoperative IMH diameter was 454 +/- 191 mum. No MH reopened during the follow-up after the initial vitreous surgery. Seven cases of CME were observed (1 in groups 1 and 2; 5 in group 3), and cataract surgery was performed in the 53 patients in group 3 with a mean delay of 11.6 months. CONCLUSIONS: Cataract extraction, CME, or preoperative MH diameter measured by optical coherence tomography were not identified as risk factors for IMH reopening.

International audience; We report a novel Fourier-transform-based implementation of coherent anti-Stokes Raman scattering (CARS) microscopy. The method employs a single femtosecond laser source and a Michelson interferometer to create two pulse replicas that are fed into a scanning multiphoton microscope. By varying the time delay between the pulses, we time-resolve the CARS signal, permitting easy removal of the nonresonant background while providing high resolution, spectrally resolved images of CARS modes over the laser bandwidth (approximately 1500 cm(-1)). We demonstrate the method by imaging polystyrene beads in solvent.