Effect of autologous growth factors on apoptosis and thickness of the outer nuclear layer in an experimental retinal degeneration model.

Retinal pigment epithelium and photoreceptor cells are a microenvironment where 90 different peptides are synthesized for transduction, visual cycle, intracellular electron transport chain, and removal of metabolic wastes. Depending on the inheritance pattern, either mutant proteins accumulate inside the cells or the energy cycle is disrupted. Disruption of homeostasis causes the cells to switch to the dormant phase; if the improper conditions last longer, then apoptosis eventually develops resulting in a loss of visual function. In neural tissues, growth factors such as neural growth factor, brain-derived neurotrophic factor, ciliary neurotrophic factor, and insulin-like growth factor are regulatory peptides for intracellular energy cycle and intracellular digestion. In this study, it has been shown histopathologically that autologous growth factors can prevent apoptosis and prevent loss of outer retinal thickness in the retinal degeneration model created with sodium iodate.

Effects of subtenon-injected autologous platelet-rich plasma on visual functions in eyes with retinitis pigmentosa: preliminary clinical results.

PURPOSE: One of the main reasons for apoptosis and dormant cell phases in degenerative retinal diseases such as retinitis pigmentosa (RP) is growth factor withdrawal in the cellular microenvironment. Growth factors and neurotrophins can significantly slow down retinal degeneration and cell death in animal models. One possible source of autologous growth factors is platelet-rich plasma. The purpose of this study was to determine if subtenon injections of autologous platelet-rich plasma (aPRP) can have beneficial effects on visual function in RP patients by reactivating dormant photoreceptors. MATERIAL AND METHODS: This prospective open-label clinical trial, conducted between September 2016 and February 2017, involved 71 eyes belonging to 48 RP patients with various degrees of narrowed visual field. Forty-nine eyes belonging to 37 patients were injected with aPRP. A comparison group was made up of 11 patients who had symmetrical bilateral narrowed visual field (VF) of both eyes. Among these 11 patients, one eye was injected with aPRP, while the other eye was injected with autologous platelet-poor plasma (aPPP) to serve as a control. The total duration of the study was 9 weeks: the aPRP or aPPP subtenon injections were applied three times, with 3-week intervals between injections, and the patients were followed for three more weeks after the third injection. Visual acuity (VA) tests were conducted on all patients, and VF, microperimetry (MP), and multifocal electroretinography (mfERG) tests were conducted on suitable patients to evaluate the visual function changes before and after the aPRP or aPPP injections. RESULTS: The best-corrected visual acuity values in the ETDRS chart improved by 11.6 letters (from 70 to 81.6 letters) in 19 of 48 eyes following aPRP application; this result, however, was not statistically significant (p = 0.056). Following aPRP injections in 48 eyes, the mean deviation of the VF values improved from - 25.3 to - 23.1 dB (p = 0.0001). Results regarding the mfERG P1 amplitudes improved in ring 1 from 24.4 to 38.5 nv/deg2 (p = 0.0001), in ring 2 from 6.7 to 9.3 nv/deg2 (p = 0.0301), and in ring 3 from 3.5 to 4.5 nv/deg2 (p = 0.0329). The mfERG P1 implicit times improved in ring 1 from 40.0 to 34.4 ms (p = 0.01), in ring 2 from 42.5 to 33.2 ms (p = 0.01), and in ring 3 from 42.1 to 37.9 ms (p = 0.04). The mfERG N1 amplitudes improved in ring 1 from 0.18 to 0.25 nv/deg2 (p = 0.011) and in ring 2 from 0.05 to 0.08 nv/deg2 (p = 0.014). The mfERG N1 implicit time also improved in ring 1 from 18.9 to 16.2 ms (p = 0.040) and in ring 2 from 20.9 to 15.5 ms (p = 0.002). No improvement was seen in the 11 control eyes into which aPPP was injected. In the 23 RP patients with macular involvement, the MP average threshold values improved with aPRP injections from 15.0 to 16.4 dB (p = 0.0001). No ocular or systemic adverse events related to the injections or aPRP were observed during the follow-up period. CONCLUSION: Preliminary clinical results are encouraging in terms of statistically significant improvements in VF, mfERG values, and MP. The subtenon injection of aPRP seems to be a therapeutic option for treatment and might lead to positive results in the vision of RP patients. Long-term results regarding adverse events are unknown. There have not been any serious adverse events and any ophthalmic or systemic side effects for 1 year follow-up. Further studies with long-term follow-up are needed to determine the duration of efficacy and the frequency of application.

Survey of Intravitreal Injection Preferences for the Treatment of Age-Related Macular Degeneration and Macular Edema Among Members of the Turkish Ophthalmological Association.

Objectives: To analyze the current preferences of ophthalmologists for the treatment of macular edema and age-related macular degeneration (AMD) and to evaluate off-label use of bevacizumab in Turkey. Materials and Methods: All members of the Turkish Ophthalmological Association were contacted by e-mail to complete an anonymous, 47-question internet-based survey. The second part of the survey (questions 36-47) was evaluated. Results: When current legal regulations were considered, ophthalmologists used bevacizumab as the first-line agent in patients with diabetic macular edema (DME), AMD, and retinal vein occlusion (RVO) (58.25%, 55.89%, and 52.29%, respectively). When economic and legal constraints were disregarded, the participants' preference for bevacizumab in the treatment of DME, AMD, and RVO decreased (11.64%, 10.58%, and 10.93%, respectively). Approximately three-quarters (75.75%) of ophthalmologists stated that dispensing multiple syringes from a single bevacizumab bottle could increase the risk of endophthalmitis. Most participants (93.68%) did not feel legally safe from harm caused by off-label bevacizumab use. However, 66.43% of ophthalmologists stated that bevacizumab is as effective as other anti-vascular endothelial growth factor (anti-VEGF) drugs. Conclusion: Bevacizumab is widely used as a first-line treatment for all indications of anti-VEGF use in the current reimbursement conditions, which preclude the right of ophthalmologists to treat according to their own preferences.

Impact of ocular and systemic risk factors on progression of geographic atrophy in age-related macular degeneration.

BACKGROUND: Geographic atrophy (GA) corresponds to an end-stage form of age-related macular degeneration and the leading cause of irreversible vision loss. The aim of this study was to investigate the role of fundus autofluorescence (FAF) patterns surrounding GA, baseline GA size, the presence of reticular pseudodrusen (RPD), the condition of the fellow eye and the presence of systemic vascular diseases (diabetes, atherosclerosis, systemic hypertension) on the progression of GA due to age-related macular degeneration. METHODS: Seventy-five eyes of 52 patients with GA were included into this retrospective study. Digital FAF images were achieved using scanning laser ophthalmoscopy. Areas of GA were measured with the Region Finder software program on an Heidelberg Retinal Angiograph 2. FAF patterns around GA were classified and the presence of RPD and systemic diseases were noted. The median follow-up of the patients was 2.6 years (interquartile range, 1-9.2). RESULTS: The median progression rate of the banded pattern (median 0.97 mm2/year) was significantly higher than the other patterns (median 0.85 mm2/year) (p = 0.03). Eyes with RPD had a significantly higher progression rate (median 1.21 mm2/year) than those without RPD (median 0.79 mm2/year) (p = 0.007). The presence of systemic diseases was not related with lesion progression rates. CONCLUSIONS: The results demonstrate that the banded pattern and the presence of RPD accelerate the progression of GA and function as predictive factors.

The Use of Fundus Autofluorescence in Dry Age-Related Macular Degeneration

Fundus autofluorescence (FAF) has been a well-known imaging method for quite some time. However, with developing technologies and novel imaging devices, FAF is being used more often to diagnose and monitor retinal diseases. The density of lipofuscin (LF) and other fluorophores in the retina have a determining role in FAF images. In dry age-related macular degeneration (AMD), hyperautofluorescence is seen in cases of increasing LF in the retina pigment epithelium, whereas hypoautofluorescence is detected in decreasing LF resulting from geographic atrophy. In recent years, studies have shown that FAF images provide prognostic information in patients with AMD. This review aims to highlight the importance of FAF imaging in dry AMD.

Survey of Intravitreal Injection Techniques and Treatment Protocols Among Members of the Turkish Ophthalmological Association.

OBJECTIVES: To describe the intravitreal injection (IVI) techniques, practices, and treatment protocols of ophthalmologists in Turkey from May 20, 2020 to June 4, 2020. MATERIALS AND METHODS: All members of the Turkish Ophthalmological Association were contacted by e-mail to complete an anonymous, 47-question internet-based survey. RESULTS: Thirteen percent of the participants prescribed prophylactic antibiotics pre-injection, 63.8% (406/636) used antibiotic drops immediately after injection, and 91.8% prescribed topical antibiotics. The majority of IVI procedures were performed in an operating room (65.3%) or clean room (33.6%). Most surgeons used sterile gloves, masks, sterile drape, sterile fenestrated cover, and sterile eyelid speculum. Multispecialists (M) preferred to wear sterile gloves more than retina specialists (RS) (99.0% vs. 95.3%; p=0.004). Also, M prescribed antibiotics more than RS (93.7% vs. 88.8%; p=0.029). RS dilated the pupil more frequently than M (48.3% vs. 39.0%) (p=0.020). RS were more familiar to use different quadrants (right p=0.012; left p=0.001). Most surgeons (82.8%) did not perform injections in both eyes on the same day. CONCLUSION: Ophthalmologists in Turkey employ a wide range of techniques in care before, during, and after IVI. In addition, IVI techniques and treatment protocols differed between RS and M. Further research is needed to elucidate best practice patterns.

Fundus Autofluorescence Changes in Age-related Maculopathy

Objectives: The aim of this study was to describe the fundus autofluorescence (FAF) findings of age-related maculopathy and risk patterns associated with FAF changes. Materials and Methods: FAF images of 150 eyes with age-related maculopathy were evaluated retrospectively. FAF patterns were classified as normal, minimal change, focal increase, patchy, linear, lace-like, reticular, and speckled pattern. Correlation between patterns and visual acuity, pattern associations at initial visit, and focal atrophy development and pattern alterations during follow-up were evaluated. Results: At initial examination, 33.3% of the eyes showed no FAF pattern. In the other eyes, the most common patterns were reticular, focal increase, and patchy pattern at rates of 18%, 14.7%, and 11.3%, respectively. There was no correlation between pattern and visual acuity at initial visit. Two coexisting patterns were observed in 4.6% eyes, and the most common pattern in these combinations was reticular pattern (85.7%). Pattern alterations were observed in 5.3% of the eyes during follow-up. Half of these alterations involved transformation to reticular pattern or addition of reticular pattern to the initial pattern. In addition, 13.3% of the eyes developed focal atrophy during follow-up. Development of focal atrophy was more common with focal increase and reticular pattern, with rates of 45% and 30%, respectively. Conclusion: Presence of reticular pattern may be a risk factor for change and progression of FAF findings in age-related maculopathy.

Multimodal imaging characteristics of quiescent type 1 neovascularization in an eye with angioid streaks.

PURPOSE: To present the multimodal imaging characteristics including optical coherence tomography angiography (OCTA) as well as indocyanine green angiography (ICGA) of quiescent type 1 neovascularization (NV) in an asymptomatic eye with angioid streaks (AS). OBSERVATIONS: A 67-year-old male patient was admitted to our clinic for routine eye examination. The presence of a quiescent type 1 NV was detected on both ICGA and OCTA in juxtafoveal localization under the retinal pigment epitheliumin the right eye. At the end of the one year of follow-up, the patient was asymptomatic and the type 1 NV was still quiescent. CONCLUSIONS AND IMPORTANCE: In comparison to ICGA, OCTA seems to be an easily repeatable non-invasive imaging tool which enables us early detection and monitoring of type 1 NV lesions even in asymptomatic patients with AS.

Optical Coherence Tomography Angiography Findings in Type-2 Macular Telangiectasia.

Objectives: To evaluate the vascular changes of idiopathic macular telangiectasia type 2 (MacTel 2) patients with optical coherence tomography angiography (OCTA) and correlate these changes with the findings of spectral domain optical coherence tomography (SD-OCT). Materials and Methods: Simultaneous SD-OCT and OCTA images of 10 eyes of 6 patients who were diagnosed as MacTel 2 in Ankara University Faculty of Medicine, Department of Ophthalmology were obtained and graded according to the OCTA grading system for MacTel 2. Results: Ten eyes of 6 patients were included. Four (66%) patients were female and 2 (34%) were male. The disease was grade 0 in 2 eyes, grade 1 in 2 eyes, grade 2 in 3 eyes, grade 3 in 1 eye, grade 4 in 1 eye, and grade 5 in 1 eye. The most common findings in grade 1, 2, and 3 non-proliferative disease were thinning of the outer retinal layers, presence of intraretinal hyporeflective layers and inner limiting membrane draping. In cases with subretinal choroidal neovascularisation (CNV) in OCTA, CNV or CNV scar was present in the B-scan SD-OCT images. In a case in which OCT was within normal limits, vascular changes consistent with grade 1 disease were observed in OCTA. On the contrary, 2 patients with significant foveal atrophy and macular hole in B-scan showed changes of early disease in OCTA. In some of the eyes, OCTA revealed an intact superficial vascular layer despite visible changes in the deep layer and the presence of neovascularisation. Conclusion: OCTA yields findings which are important for understanding the pathogenesis of the disease and providing better follow-up. Contrary to fundus fluorescein angiography, changes in the deep arterial plexus in the early disease and CNV can be clearly observed with OCTA. To achieve the best results in clinical practice, en face flow maps should be evaluated together with B-scan SD-OCT images.