Optical Scattering from Vitreous Floaters.

Vitreous "floaters" are a common entoptic phenomenon that can result in significant reduction in quality of life in a proportion of sufferers. The authors use a computational mathematical model based on Fourier optics and reflection and transmission coefficients calculated for a planar type II collagen opacity suspended in aqueous to show that floaters are perceived by the patient through interference effects that result in significant variations in intensity on the retina when viewing a constant brightness surface. The model also predicts that backscattered intensity from floaters is ten thousand to one million times lower than the variations in intensity produced on the retina, which demonstrates that the visible effects of floaters for the patient can be highly significant, whereas clinical observation of the vitreous may be entirely unremarkable. Importantly, the results also demonstrate that floaters do not need to be opaque to cause symptoms, with only small differences in refractive index between the floater material and the surrounding vitreous needed to produce significant optical effects. The model predicts that pupil size is an important factor in determining the severity of symptoms from floaters, with constricted pupils giving much greater effect than dilated pupils. Finally, the authors' model predicts that floaters degrade contrast sensitivity function, with greatest degradation occurring in the 5-40 cycles per degree spatial frequency range and that the effects of shadowing caused by floaters are very strongly correlated to the predicted degradation of contrast sensitivity function. Bioelectromagnetics. 43:90-105, 2022. © 2021 The Authors. Bioelectromagnetics published by Wiley Periodicals LLC on behalf of Bioelectromagnetics Society.

VISUAL OUTCOME OF EARLY VITRECTOMY AND INTRAVITREAL ANTIBIOTICS IN ACUTE POSTSURGICAL AND POSTINTRAVITREAL INJECTION ENDOPHTHALMITIS: European Vitreo-Retinal Society Endophthalmitis Study Report Two.

PURPOSE: To evaluate the visual outcome associated with intravitreal antibiotics (IVA) and pars plana vitrectomy (PPV) for acute postprocedure endophthalmitis. METHODS: Data from 237 eyes presenting with acute postprocedure endophthalmitis were collected from 57 retina specialists in 28 countries. All eyes were treated with IVA on the day of presentation. We classified eyes according to the method of treatment used as IVA and early PPV (IVA + PPV within 1 week of presentation) groups. RESULTS: After exclusion of ineligible eyes, data from 204 eyes were analyzed. The mean (SD) age of patients was 62.7 (21.8) years and 69.3 (12.7) years in the IVA and PPV groups, respectively (P = 0.18). Endophthalmitis secondary to cataract, intravitreal injections, PPV, and other intraocular procedures represented 64.2%, 16.2%, 13.7%, and 5.9% of cases, respectively. Intravitreal antibiotics alone were administered in 55 eyes (27.0%), and early PPV was performed in 149 eyes (73.0%). No difference was found between groups in the final visual acuity of ≥20/60 (43.6%, 65 eyes vs. 34.5%, 19 eyes) and ≤counting fingers (30.9%, 46 eyes vs. 36.4%, 20 eyes) for IVA versus early PPV groups, respectively. Vision of light perception (odds ratio = 12.2; 95% confidence interval: 2.0-72.6) and retinal detachment (odds ratio = 7.7; 95% confidence interval: 1.5-409) at baseline were predictive of vision of ≤counting fingers. Retinal detachment at baseline (odds ratio = 20.4; 95% confidence interval: 1.1-372.1) was predictive of final retinal detachment status. CONCLUSION: The current retrospective multicenter cohort of eyes with acute postprocedure endophthalmitis reports similar outcomes after treatment with IVA alone when compared with IVA and early PPV within 1 week of presentation.

Management of optic disc pit maculopathy: the European VitreoRetinal society optic pit study.

PURPOSE: To evaluate a variety of techniques, and their anatomical and functional results, for the treatment of optic disc pit maculopathy (ODP-M). A secondary aim was to report on results of secondary procedures in cases of initial failure or recurrence. METHODS: Multicentre retrospective study of 95 eyes with ODP-M, treated by 25 surgeons from 12 countries. Primary outcomes were anatomical resolution of subretinal fluid (SRF), intraretinal fluid (IRF) and visual acuity (VA) at 12 months. RESULTS: Higher rates of SRF and IRF resorption were achieved in eyes treated with pars plana vitrectomy (PPV) compared to external laser with or without tamponade: 64/72 (88.9%) versus 8/14 (57.1%) for SRF (p = 0.003), and 50/59 (84.7%) versus 3/10 (30%) for IRF (p = 0.002). The addition of juxtapapillary laser or internal limiting membrane (ILM) peel during PPV did not improve SRF or IRF resolution. Pars plana vitrectomy (PPV) with tamponade and PPV with tamponade plus endolaser were associated with significant visual gain. In the former group, VA improved from a mean of logMAR 0.91 (20/162), to a mean of logMAR 0.52 (20/66) at 12 months; in the latter group, VA improved from a mean of logMAR 0.82 (20/132) to a mean of logMAR 0.47 (20/59) at 12 months. Retreatments were performed in 14 eyes (15.7%), only enhancing anatomical outcomes. CONCLUSION: Vitrectomy with tamponade had better final outcomes than external laser treatment with or without gas tamponade. Laser endophotocoagulation and ILM peel provided no additional benefit. A secondary treatment resulted in anatomical but not functional improvement.

Survey of the use of laser protective eyewear among international retina specialists: a European vitreoretinal society study.

OBJECTIVE: To report the trends for the use of eye protection methods during retinal laser in clinic and operating room. METHODS AND ANALYSIS: Retrospective analysis of a 14-item survey questionnaire submitted to the European Vitreoretinal Society members. RESULTS: Responses from 630 members were analysed. Most of the respondents practised in Europe (52.7%), followed by North America (21.0%). The majority of respondents had laser filters in the microscope for the operating surgeon (92.1%), or used protective goggles (6.8%). Only 38.9% of respondents indicated that auxiliary staff in the operative room used protective goggles during laser treatment. Three-dimensional retina viewing system was used by only 22.5% of respondents, of those, 34.5% reported use of laser protection goggles by the operating surgeon. Rates of laser protection by auxiliary staff were 62.9% for indirect laser and 60.8% for slit lamp laser. We found a higher rate for use of laser protection by auxiliary staff in North America-based practices for endolaser (p<0.00001), laser indirect ophthalmoscope (p<0.00001) and slit lamp laser (p=0.00033) compared with the rest of the world. CONCLUSION: The use of laser protection methods is routinely adopted by the physicians in the operating room and clinic, but less so by their assisting or auxiliary staff.

Management of vitreous floaters: an international survey the European VitreoRetinal Society Floaters study report.

BACKGROUND/OBJECTIVES: To evaluate the efficacy and safety of pars plana vitrectomy for symptomatic floaters. SUBJECTS/METHODS: Forty-eight vitreoretinal surgeons from 16 countries provided information on 581 eyes who underwent vitrectomy for floaters in this retrospective survey study conducted by European VitreoRetinal Society. Percentage symptomatic improvement, incidence of retinal tears/detachment and post-vitrectomy cataract surgery, and the factors associated with satisfaction and complications were investigated. RESULTS: Ninety-two percent were satisfied with the results, with 86.3% reporting complete resolution of daily-life symptoms. Overall satisfaction was lower in patients with smaller vitreous opacities at presentation (OR:0.4). Iatrogenic retinal breaks occurred in 29 eyes (5%). Core vitrectomy and cut rates of 1500-4000 or >4000 cuts/min were associated with lower risk of retinal breaks than complete vitrectomy (OR:0.05) and cut rates < 1500 cuts/min (OR: 0.03, 0.12, respectively). Fourteen eyes (2.4%) developed retinal detachment at a median of 3 months; and 84 (48.6%) developed cataract at a median of 16 months post-vitrectomy. CONCLUSIONS: Pars plana vitrectomy resulted in high patient satisfaction with relatively low rate of severe complications in a large group of patients. The procedure may be safer when core vitrectomy and cut rates > 1500 cuts/min are favoured. Proper patient selection and informed consent are the most important aspects of surgery.

Management of bacterial postoperative endophthalmitis and the role of vitrectomy.

Management of postoperative bacterial endophthalmitis was explored in the Endophthalmitis Vitrectomy Study37 in 1995, which has underpinned the core protocols in treatment ever since. While surgical techniques have continued to evolve, little has changed in the overall clinical management as no further large randomized controlled trials have taken place. We review the literature addressing the incidence of endophthalmitis, pathogens, antibiotic therapies, and the role of vitrectomy. We suggest an update to management protocols based on available evidence. While vitreous culture remains the gold standard for diagnosis, new techniques allow bacterial identification after antibiotic administration, so injection should be initiated immediately. Current antibiotic regimes are comprehensive and do not need changing. Intravitreal antibiotics should not be repeated at 48 hours after initial treatment. Vitrectomy should be considered instead if the clinical picture is not improving.