Guillaume Debellemanière

Reliability of cone counts using an adaptive optics retinal camera

To assess the reproducibility and repeatability of cone imaging in healthy human eyes, using the RTx‐1 Adaptive Optics Retinal Camera and its proprietary cone‐counting software.

Quantification of cone loss after surgery for retinal detachment involving the macula using adaptive optics

Aims To image the cones in eyes with anatomically successful repair of retinal detachment (RD) involving the macula and in healthy fellow eyes using an adaptive optics (AO) camera and to correlate the results to clinical outcomes. Methods Twenty-one patients (42 eyes) operated for macula-off RD were imaged 6 weeks after surgery using an AO camera (RTX 1, Imagine Eyes, Orsay, France). Cone density (cells/mm2), spacing between cells (µm) and the percentage of cones with six neighbours were measured. Best-corrected visual acuity (BCVA) and thickness of the inner segment ellipsoid (ISe) band imaged by SD-optical coherence tomography were also measured. Results The parafoveal cone density was decreased in eyes operated for RD (mean±SD 14 576±4035/mm2) compared with fellow eyes (20 589±2350/mm2) (p=0.0001). There was also an increase in cone spacing (10.3±2.6 vs 8.0±1.0.9 µm, respectively, p<0.0001). The nearest-neighbour analysis revealed a reduction in the percentage of cones with six neighbours (36.5±4.2 vs 42.7±4.6%, p=0.0003). The ISe thickness, thinner in the operated eyes, was correlated to the cone density (r=0.62, p<0.0001). BCVA was significantly correlated to cone density (r=0.8, p<0.001). Conclusions There was a decrease in the cone density after RD with an estimated loss of one-third of the cones. Postoperative visual acuity was highly correlated with the cone density. AO may be a valuable prognostic tool after RD surgery.

Impact of Surgical Learning Curve in Descemet Membrane Endothelial Keratoplasty on Visual Acuity Gain.

Purpose: To evaluate the learning curve for graft preparation and graft unrolling during Descemet membrane endothelial keratoplasty (DMEK) and to assess the evolution of visual acuity gain and percentage cell loss with experience. Methods: The first 109 DMEK procedures performed by a single surgeon (A.S.) at the Rothschild Foundation Ophthalmology Hospital in Paris, France, between March 2012 and November 2014 were included. Best-corrected visual acuity and endothelial cell density were recorded preoperatively and again 1 week, 1 month, 3 months, and 6 months after DMEK. Donor age and ECC were registered. Graft preparation time and graft unrolling time were assessed using video recording. Incidence and types of complications were noted. Results: The number of cases necessary to reach 90% of the plateau of the learning curve was 68 for preparation time and 46 for unrolling time in this model. There was no correlation between the best-corrected visual acuity gain at 6 months postsurgery and the learning curve. The percentage cell loss was found to be significantly lower with experience (R2 = 0.17, P = 0.0011). Conclusions: Surgical experience allowed faster graft preparation and faster unrolling time in DMEK. Neither experience nor percentage cell loss influenced postoperative visual acuity gain. The number of procedures needed to reach a good standard of care was estimated to be 50 in our patient database.

Evaluation of microbial contamination of corneal transplants: one-year report from a French regional eye bank.

Purpose: The aim of this study was to report the rate of corneal transplant microbial contamination in a single major eye bank and to identify the contributive factors. Methods: The contamination rate of 1156 organ-cultured corneas harvested in 2010 in a single eye bank (EFS Bourgogne Franche-Comté, Besançon, France) was studied together with the following factors: age, sex, tissue-recovery method (single or multiorgan donors), death-to-excision time, excision-to-reception time, cause of death, positive serology, and endothelial cell count. Student t test for quantitative data was used for statistical comparisons between groups. Qualitative data were assessed using the &khgr;2 test. Results: The contamination rate was 5.5%. Most contaminations were of bacterial origin (77.9%), with Staphylococcus species (62.3%) being predominant. Fungal contaminations (19.1%) were dominated by Candida species (76.9%). Death resulting from cancer was related to a higher risk of corneal contamination (P < 0.001). The other factors were not related to an increased risk of contamination. Conclusions: The rate of microbiological contamination of corneal transplants remains low. However, special caution should be exercised with grafts collected from patients dying from cancer. To minimize this risk, further studies on the antibacterial effect of the conservation media should be conducted in the context of increased bacterial resistance.

Reflectivity of the Outer Retina on Spectral-Domain Optical Coherence Tomography as a Predictor of Photoreceptor Cone Density

PURPOSE To investigate the relationship between outer retinal reflectivity on spectral-domain optical coherence tomography and cone density in the corresponding area. DESIGN Prospective cross-sectional observational study. METHODS In this institutional-based study, 20 eyes of 10 patients presenting maculopathies with various degrees of impairment of the photoreceptor layer (central serous chorioretinopathy, chronic central serous chorioretinopathy, maculopathy associated with hydroxychloroquine, and healthy eyes) were studied. Selection criteria were intended to ensure good image quality. Inner segment ellipsoid band reflectivity, global retinal reflectivity, and relative inner segment ellipsoid reflectivity (defined as the ratio of inner segment ellipsoid band reflectivity on overall retinal reflectivity) were measured on a longitudinal reflectance profile extracted from the spectral-domain optical coherence tomography B-scan. The cone metrics were measured in the same region of interest, located in the perifoveal area, using an adaptive optics retinal camera. RESULTS Inner segment ellipsoid and relative ellipsoid reflectivity were closely correlated with cone density (Pearson r: 0.72 and 0.70, respectively, P < .01). CONCLUSION Outer retinal reflectivity on the transversal optical coherence tomography scan can be correlated to adaptive optics in terms of photoreceptor density. This quantitative approach using optical coherence tomography images could have important implications in the management of maculopathies.

Assessment of parafoveal cone density in patients taking hydroxychloroquine in the absence of clinically documented retinal toxicity.

To measure cone density in patients taking hydroxychloroquine (HCQ), with no clinical evidence of maculopathy.

Neisseria sicca Endocarditis Complicated by Intracranial and Popliteal Aneurysms in a Patient with a Bicuspid Aortic Valve

We report a case of infective endocarditis due to Neisseria sicca complicated by intracranial and popliteal aneurysms and hepatic and splenic infarcts in a patient with a bicuspid aortic valve. No predisposing factor other than poor dental condition was found. The patient fully recovered after antibiotic therapy, aortic and mitral valve replacement, endovascular occlusion of the middle-cerebral artery aneurysm, and surgical treatment of the popliteal artery aneurysm.

Three-dimensional Printing of Optical Lenses and Ophthalmic Surgery: Challenges and Perspectives

PURPOSE To determine whether the historical Ridley lens could be reproduced with current three-dimensional lens printing technology. METHODS A reproduction of the Ridley lens was printed using the Printoptical Technology (LUXeXceL Group BV, Kruiningen, Netherlands). Photographs and electron microscopy images were taken. Dimensions, weight, anterior and posterior surface radius of curvature, optical transmission, back optical power, and surface analysis using interferometry were obtained. RESULTS The printed lens was 8.10 ± 0.01 mm in diameter, 2.50 ± 0.01 mm thick, and weighed 117 mg. The anterior radius of curvature was 14.63 ± 0.69 mm and the posterior radius of curvature was 10.88 ± 0.22 mm. The back focal length in air was 14.1 ± 0.4 mm. An average 75% transmission in the visible spectrum (400 to 700 nm) was achieved. Surface analysis showed significant surface roughness. CONCLUSIONS The printed reproduction of the Ridley lens was far from current clinical standards, but had the properties of a biconvex lens.

Optical and morphological characterization of a 3D printed intraocular lens

Purpose Three‐dimensional printing (or “additive manufacturing”) is a technology which allows to create a three dimensional object by building it layer by successive layer. It is especially interesting for objects that are produced in little series and that require a high degree of customization, as it allows economies of scale and potentially unlimited design possibilities. Those characteristics are particularly relevant to intraocular lenses used in cataract surgery, in a personalized medicine approach. Despite technical barriers, additive manufacturing of good quality lenses without post‐processing is now achievable. We aimed to determine if the historical Ridley lens was able to be reproduced with current 3D lens printing technology.