Swept-source optical coherence tomography angiography findings in a case of primary vitreoretinal lymphoma over a three-year follow-up

BACKGROUND

Vitreoretinal lymphoma (VRL) still represents a diagnostic challenge for retinal specialists. Early diagnosis and treatment are critical for a better prognosis. Several diagnostic tools have proven helpful in the identification of VRL abnormalities. However, swept-source OCT angiography (SS-OCT-A) findings and their long-term follow-up are yet to be explored.

CASE PRESENTATION

a 42-year-old man presented with blurred vision in his left eye for 2 weeks. He denied any systemic symptoms. A multimodal imaging examination was performed, raising the clinical suspicion of VRL and guiding the ensuing diagnostic procedures. The patient underwent treatment and at the last FU visit three years later, no disease signs were present on fundus examination, nor on oncologic evaluation. Some novel SS-OCT-A features were identified, and uncommonly reported findings were examined over a long-term follow-up. At baseline multiple hyperreflective alterations were detected on the enface outer retina slabs and choriocapillary analysis revealed low reflectance areas in the foveal and parafoveal areas. One month after the first presentation, multiple hyperreflective retinal lesions in a vertical shape were detected on OCT which appeared on midretinal slabs of enface SS-OCT-A as hyperreflective spots mainly located near second-order retinal vessels. These alterations remarkably reduced after treatment.

CONCLUSION

SS-OCT-A may be a useful imaging technique in the detection of VRL, providing ophthalmologists additional findings that assist the diagnosis and follow-up of this disease. This may prove useful for a more timely and precise diagnosis, prompt therapy, and treatment response monitoring. The original aspects found in this case may provide grounds for future studies, ultimately fostering a better understanding of the disease.

Fovea-sparing internal limiting membrane peeling with inverted flap technique versus standard internal limiting membrane peeling for symptomatic myopic foveoschisis

To study the long-term outcomes of standard ILM peeling and fovea sparing with inverted flap (FSIF) peeling for symptomatic myopic foveoschisis (MF). This retrospective observational study included 36 eyes of 34 consecutive patients who underwent vitrectomy with standard ILM peeling and FSIF peeling for MF between April 2012 and march 2020. The primary outcome measures included best-corrected visual acuity (BCVA) and central foveal thickness (CFT) at 1 month and final visit and postoperative development of macular hole. There were 14 eyes in the standard ILM peeling group and 22 eyes and in the FSIF peeling groups with a mean FU of 34.2 months (SD 23.3; min. 12-max. 96) and 27.7 months (SD 14.9; min. 12-max. 63), respectively. In both groups BCVA was not significantly improved at 1 month but improved at last visit from 0.55 ± 0.21 to 0.37 ± 0.29 in the standard ILM peeling group (P = 0.0154) and from 0.57 ± 0.27 to 0.28 ± 0.23 in the FSIF peeling group (P < 0.0001). At 1 month and final visit CMT decreased from 572 ± 183.5 µm to 277.5 ± 95.2 µm and to 250.4 ± 96.1 µm, respectively, in the standard ILM peeling group and from 589.9 ± 189.8 µm to 383 ± 110.1 µm and 162.3 ± 74.8 µm in the FSIF peeling group (P < 0.001 for both groups at both time-points). The preoperative and postoperative BCVA and CMT showed no significant differences between groups. Three of the eyes in the standard ILM peeling group developed postoperative macular hole at 1, 10, 24 months, respectively, and none of the eyes in the FSIF peeling group. Multivariate analysis revealed that a better BCVA was the only independent factor correlated with the final BCVA. In this study, standard ILM peeling and FSIF peeling were both beneficial in improving the anatomy and function of eyes with MF. Postoperative MH may occur up to 2 years after standard peeling and seem effectively prevented by FSIF peeling.

The light-dependent pseudo-capacitive charging of conjugated polymer nanoparticles coupled with the depolarization of the neuronal membrane

The mechanism underlying visual restoration in blind animal models of retinitis pigmentosa using a liquid retina prosthesis based on semiconductive polymeric nanoparticles is still being debated. Through the application of mathematical models and specific experiments, we developed a coherent understanding of abiotic/biotic coupling, capturing the essential mechanism of photostimulation responsible for nanoparticle-induced retina activation. Our modeling is based on the solution of drift-diffusion and Poisson-Nernst-Planck models in the multi-physics neuron-cleft-nanoparticle-extracellular space domain, accounting for the electro-chemical motion of all the relevant species following photoexcitation. Modeling was coupled with electron microscopy to estimate the size of the neuron-nanoparticle cleft and electrophysiology on retina explants acutely or chronically injected with nanoparticles. Overall, we present a consistent picture of electrostatic depolarization of the bipolar cell driven by the pseudo-capacitive charging of the nanoparticle. We demonstrate that the highly resistive cleft composition, due to filling by adhesion/extracellular matrix proteins, is a crucial ingredient for establishing functional electrostatic coupling. Additionally, we show that the photo-chemical generation of reactive oxygen species (ROS) becomes relevant only at very high light intensities, far exceeding the physiological ones, in agreement with the lack of phototoxicity shown in vivo.

Towards a Long-Read Sequencing Approach for the Molecular Diagnosis of RPGRORF15 Genetic Variants

Sequencing of the low-complexity ORF15 exon of RPGR, a gene correlated with retinitis pigmentosa and cone dystrophy, is difficult to achieve with NGS and Sanger sequencing. False results could lead to the inaccurate annotation of genetic variants in dbSNP and ClinVar databases, tools on which HGMD and Ensembl rely, finally resulting in incorrect genetic variants interpretation. This paper aims to propose PacBio sequencing as a feasible method to correctly detect genetic variants in low-complexity regions, such as the ORF15 exon of RPGR, and interpret their pathogenicity by structural studies. Biological samples from 75 patients affected by retinitis pigmentosa or cone dystrophy were analyzed with NGS and repeated with PacBio. The results showed that NGS has a low coverage of the ORF15 region, while PacBio was able to sequence the region of interest and detect eight genetic variants, of which four are likely pathogenic. Furthermore, molecular modeling and dynamics of the RPGR Glu-Gly repeats binding to TTLL5 allowed for the structural evaluation of the variants, providing a way to predict their pathogenicity. Therefore, we propose PacBio sequencing as a standard procedure in diagnostic research for sequencing low-complexity regions such as RPGRORF15, aiding in the correct annotation of genetic variants in online databases.

Use of Heavy Silicon Oil as Intraocular Tamponade for Inferior Retinal Detachment Complicated by Proliferative Vitreoretinopathy: A Multicentric Experience

INTRODUCTION

This is a multicentric study on the use of heavy silicon oil (HSO) as an intraocular tamponade for inferior retinal detachment (RD) complicated by proliferative vitreoretinopathy (PVR).

METHODS

139 eyes treated for RD with PVR were included in the study. 10 (7.2%) were affected by primary RD with inferior PVR, while 129 (92.8%) were affected by recurrent RD with inferior PVR. 102 eyes (73.9%) had received a silicon oil (SO) tamponade in a previous intervention prior to receiving HSO. Mean follow-up was 36.5 (standard deviation = 32.3) months.

RESULTS

The median interval between HSO injection and removal was 4 months (interquartile range: 3). At the time of HSO removal, the retina was attached in 120 eyes (87.6%), whereas in 17 eyes (12.4%), it had re-detached while the HSO was in situ. 32 eyes (23.2%) showed recurrent RD. A subsequent RD relapse was observed in 14.2% of cases with no RD at the time of HSO removal, and in 88.2% if an RD was present at the time of HSO removal. Advancing age showed a positive association with retinal attachment at the end of follow-up, while the risk of RD relapse at the end of the follow-up showed a significant negative association with HSO tamponade duration and with the use of SO rather than air or gas as post-HSO tamponade materials. Mean best corrected visual acuity was 1.1 logarithm of minimum angle of resolution at all follow-up time points. 56 cases (40.3%) needed treatment for elevated intraocular pressure (IOP), with which no clinically relevant variables were associated during follow-up.

CONCLUSION

HSO represents a safe and effective tamponade in cases of inferior RD with PVR. The presence of RD at the time of HSO removal is a negative prognostic factor for the development of a subsequent RD relapse. According to our findings, in cases of RD at the time of HSO removal, a short-term tamponade should definitely be avoided, in favor of SO. Special attention must be paid to the risk of IOP elevation, and patients should be closely monitored.

Infrared analysis in the aqueous humor of patients with uveitis: Preliminary results

Inflammatory processes affecting the uvea result in a temporary o permanent blurred vision and represent an important cause of visual impairment worldwide. It is often hard to make a precise diagnosis which is dependent on the clinical expertise, diagnostic tests, laboratory investigations in blood and sometimes in the aqueous humor (AH). With the aim of obtaining proof of principle Fourier Transformed Infrared (FT-IR) absorbance spectroscopy was applied to study the molecular composition of 72 AH samples collected in 26 patients with uveitis and in 44 controls. The unsupervised exploration of the internal structure of the dataset by principal component analysis reduced hundreds IR variables to those most representative allowing to obtain the predictive model that distinguished the AH spectra of patients with uveitis from controls. The same result was obtained by unsupervised agglomerative cluster analysis. After labeling the spectra with some clinical information it was observed that most severe uveitis with active processes were grouped separately from chronic and relapsing uveitis and controls. The consistence of prediction models is discussed in the light of supporting etiological diagnosis by machine learning processes. In conclusion, proof of principle has been obtained that the IR spectral pattern of AH may reflect particular uveal diseases.

Lamellar macular defects: are degenerative lamellar macular holes truly degenerative?

Purpose

To investigate morpho-functional changes after surgical treatment for ERM foveoschisis or lamellar macular hole (LMH), and to evaluate whether the two entities are associated with different healing processes and long-term outcomes.

Design

Retrospective interventional case series.

Methods

A total of 56 eyes, treated for lamellar macular defects and followed up for 24 months, were enrolled. The eyes were divided into two groups: 34 with ERM foveoschisis and 22 with LMH. Changes in the following features were evaluated and compared between the two groups: best-corrected visual acuity (BCVA), external limiting membrane (ELM) and ellipsoid zone (EZ) defects, central foveal thickness (CFT), and autofluorescence (FAF) diameter and area.

Results

After surgery, progressive BCVA improvement was observed with no significant difference between the two groups (p-value: 0.06). An increased number of eyes with intact outer-retinal layers was found both in the ERM foveoschisis and LMH groups. FAF diameter and area decreased significantly throughout the FU with no significant difference between the two groups (p-value: 0.2).

Conclusion

In the present study, significant functional and microstructural improvements were observed after surgery for both ERM foveoschisis and LMH, demonstrating considerable repair potential in both types of lamellar defects. These findings question the true "degenerative" nature of LMH.

Intravitreal Brolucizumab for Neovascular Age-Related Macular Degeneration in a Vitrectomized Eye

The efficacy of intravitreal anti-VEGF may be reduced in vitrectomized eyes due to accelerated drug clearance. Given its longer durability, brolucizumab may represent a suitable therapeutic option. However, its efficacy in vitrectomized eyes remains to be explored. Herein, we describe the management of a macular neovascularization (MNV) in a vitrectomized eye with brolucizumab after unsuccessful treatment with other anti-VEGF. A 68-year-old male was treated with pars plana vitrectomy for epiretinal membrane in his left eye (LE) in 2018. After surgery, best corrected visual acuity (BCVA) improved to 20/20 with a remarkable reduction of metamorphopsia. After 3 years, the patient returned, presenting visual loss in the LE due to MNV. He was treated with intravitreal bevacizumab injections. However, after the loading phase, an increased lesion size and exudation with worsening BCVA were detected. Therefore, the treatment was switched to aflibercept. However, after three monthly intravitreal injections, further worsening was recorded. Treatment was then switched to brolucizumab. Anatomical and functional improvement was noticed 1 month after the first brolucizumab injection. Two additional injections were performed, and further improvement was recorded with BCVA recovery to 20/20. At the last follow-up visit 2 months after the third injection, no recurrence was detected. In conclusion, determining whether anti-VEGF injections are efficacious for vitrectomized eyes would be helpful for ophthalmologists managing such patients, as well as when considering pars plana vitrectomy in eyes at risk of MNV. In our case, brolucizumab was found to be effective after unsuccessful treatment with other anti-VEGF. Additional studies are required to evaluate the safety and efficacy of brolucizumab for MNV in vitrectomized eyes.

The p-ERG spatial acuity in the biomedical pig under physiological conditions

Pigs are becoming an important pre-clinical animal species for translational ophthalmology, due to similarities with humans in anatomical and physiological patterns. Different models of eye disorders have been proposed, and they are good candidates to assess biocompatibility/functionality of retinal prostheses. Electroretinography is a common tool allowing to gain information on retinal function, with several types of electroretinogram (ERG) been implemented including full field (ff-ERG), multifocal (mf-ERG) and pattern (p-ERG). p-ERG represents a valuable tool to monitor Retinal Ganglion Cells (RGCs) activity and can be used to calculate p-ERG spatial acuity. Unfortunately, scarce methodological data are available regarding recording/interpretation of p-ERG and retinal acuity in biomedical pigs yet enhancing knowledge regarding pig vision physiology will allow for more refined and responsible use of such species. Aim of this study was to record p-ERG in juvenile pigs to functionally assess visual acuity. Six female hybrid pigs underwent two p-ERG recording sessions at 16 and 19 weeks of age. Photopic ff-ERG were also recorded; optical coherence tomography (OCT) and histology were used to confirm retinal integrity. ff-ERG signals were repeatable within/across sessions. All p-ERG traces consistently displayed characterizing peaks, and the progressive decrease of amplitude in response to the increment of spatial frequency revealed the reliability of the method. Mean p-ERG spatial acuities were 5.7 ± 0.14 (16 weeks) and 6.2 ± 0.15 cpd (19 weeks). Overall, the p-ERG recordings described in the present work seem reliable and repeatable, and may represent an important tool when it comes to vision assessment in pigs.

Destructive inflammatory reaction after an autologous retinal pigment epithelium and choroid transplantation: no detection of an auto-immune response

Purpose

Five patients who underwent uncomplicated retinal pigment epithelium (RPE)-choroid transplantation for neovascular age-related macular degeneration developed a destructive inflammatory reaction causing subretinal fluid accumulation and extensive RPE atrophy in the graft. We hypothesized that this inflammation could be caused by an auto-immune response against the graft, resulting in circulating auto-antibodies. The aim of our study was to examine a potential autoimmune origin, which would allow a more targeted therapy approach.

Methods

Five above-mentioned patients and four control groups of five patients each were included: 1) after uncomplicated RPE-choroid transplantation, 2) after full macular translocation, 3) treated with anti-vascular endothelial growth factor, and 4) healthy controls. Histopathology of rejected graft tissue was performed using standard procedures. Presence of RPE-choroid autoantibodies in serum was examined by indirect immunofluorescence and Western blot, and human leukocyte antigen (HLA) typing was performed.

Results

Histopathological examination of an explanted graft showed infiltration of T-lymphocytes and macrophages in the choroid and RPE, and an increased number of B-cell lymphocytes were found in the choroid. Indirect immunofluorescence showed weak RPE-choroid autoantibody immunoreactivity in three patients of different groups. Western blot did not show specific RPE-choroid autoantibody immunoreactivity and no difference of HLA genotypes between the groups was found.

Conclusions

Although local mononuclear inflammatory cell infiltration and a high number of B-lymphocytes were observed in an explanted graft, we did not detect serological evidence of an autoimmune origin of the postoperative inflammation using direct immunofluorescence and Western Blot. Alternatively, the graft failure may have been caused by local innate inflammation, triggered by breakdown of tolerance. Based on our current findings of this small study group, we have no rationale to pursue therapies targeted towards autoreactive graft failure. More research is needed to confirm our findings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12348-022-00305-2.

Light-induced charge generation in polymeric nanoparticles restores vision in advanced-stage retinitis pigmentosa rats

Retinal dystrophies such as Retinitis pigmentosa are among the most prevalent causes of inherited legal blindness, for which treatments are in demand. Retinal prostheses have been developed to stimulate the inner retinal network that, initially spared by degeneration, deteriorates in the late stages of the disease. We recently reported that conjugated polymer nanoparticles persistently rescue visual activities after a single subretinal injection in the Royal College of Surgeons rat model of Retinitis pigmentosa. Here we demonstrate that conjugated polymer nanoparticles can reinstate physiological signals at the cortical level and visually driven activities when microinjected in 10-months-old Royal College of Surgeons rats bearing fully light-insensitive retinas. The extent of visual restoration positively correlates with the nanoparticle density and hybrid contacts with second-order retinal neurons. The results establish the functional role of organic photovoltaic nanoparticles in restoring visual activities in fully degenerate retinas with intense inner retina rewiring, a stage of the disease in which patients are subjected to prosthetic interventions.

Retinal dystrophies such as Retinitis pigmentosa are among the most prevalent causes of inherited incurable legal blindness. Here the authors demonstrate that conjugated polymer nanoparticles reinstate visual functions in aged rats with fully degenerated and rewired retinas.

SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY FINDINGS IN A CASE OF PACHYCHOROID NEOVASCULOPATHY IN RETINITIS PIGMENTOSA

PURPOSE

To report a rare case of pachychoroid neovasculopathy in retinitis pigmentosa (RP) and to describe its features and changes after treatment with bevacizumab as documented by swept-source optical coherence angiography.

METHODS

A case report of a 69-year-old man with a history of RP who presented at our clinic with an acute decrease in visual acuity (Best corrected visual acuity) in his left eye.

RESULTS

Upon the first examination, best-corrected visual acuity in the left eye was 20/50. Fundus examination and fundus autofluorescence showed bilaterally typical features of RP, and enhanced depth imaging-optical coherence tomography revealed a pachychoroid pattern. Fluorescein angiography and indocyanine green angiography suggested the presence of a choroidal neovascularization in the left eye, although no clear evidence of any neovascular network could be identified. Swept-source optical coherence angiography was performed, confirming the presence of a choroidal neovascularization network. The patient was treated with 2 monthly intravitreal injections of bevacizumab. After treatment, BVCA improved to 20/25, and no evidence of the vascular network was detectable on swept-source optical coherence angiography.

CONCLUSION

Our case reports the uncommon association of RP with pachychoroid neovasculopathy. Swept-source optical coherence angiography proved to be a useful imaging technique for the diagnosis and follow-up of this condition. Intravitreal bevacizumab represents an effective treatment for choroidal neovascularization associated with RP.

The prevalence of vitreomacular adhesion in eyes with macular oedema secondary to retinal vein occlusion selected for intravitreal injections

PURPOSE

To assess the prevalence of vitreomacular adhesion (VMA) in consecutive naïve eyes diagnosed with macular oedema (ME) secondary to retinal vein occlusion (RVO) and to longitudinally evaluate the incidence of vitreomacular interface changes over time and the influence on response to treatment.

DESIGN

Retrospective cross-sectional analysis and longitudinal cohort study conducted at two Italian tertiary referral centres.

METHODS

A total of 295 eyes, treated with intravitreal ranibizumab and/or dexamethasone for ME secondary to RVO between June 2008 and May 2018, were enrolled in the study. 280 fellow eyes met the inclusion criteria and were included as control group. The vitreomacular interface status was evaluated by spectral domain optical coherence tomography (OCT) and graded according to the OCT-based International Classification System developed by the International Vitreomacular Traction Study (IVTS) group.

RESULTS

At baseline, VMA was present in 130 (44.07%) RVO eyes and 142 (50.7%) control eyes (no statistically significant difference was found; p = 0.455). Mean follow-up (FU) was 35.98 months (min 6 - max 112). Throughout the FU, the incidence of spontaneous release of VMA (RVMA) in RVO eyes was significantly higher in comparison with that of the control group [59 (41.84%) RVO eyes versus 18 (12.33%) control eyes; p < 0.0001]. The number of injections in VMA+ eyes was significantly higher when compared with VMA- eyes. No significant difference was found between VMA+ and VMA- eyes regarding their mean best-corrected visual acuity (BCVA) at baseline and at each annual time point (p = 0.2). Differences in central macular thickness (CMT) were significant only at the baseline evaluation (p = 0.0303).

CONCLUSIONS

Vitreomacular adhesion (VMA) was not found to be more prevalent in eyes with RVO compared to healthy fellow eyes, and RVO, in turn, did not result in a higher persistence of VMA over time. This suggests that VMA and RVO might be two independent retinal phenomena, with no mutual pathogenetic influence. Vitreomacular adhesion (VMA) might have an impact on the response to treatment, since it was found to result in a more intensive treatment regimen; however, it did not affect visual and anatomic outcomes. These results do not support vitrectomy or PVD induction in the prevention, nor the treatment, of RVO.

Temporal variation of optical coherence tomography biomarkers as predictors of anti-VEGF treatment outcomes in diabetic macular edema

PURPOSE

To report a longitudinal analysis of specific optical coherence tomography (OCT) features in eyes with diabetic macular edema (DME) treated with anti-VEGF.

METHODS

A total of 133 eyes of 103 consecutive patients with center-involving DME were included in the study. The eyes were treated between August 2008 and April 2019 with three monthly intravitreal anti-VEGF injections, either with or without prompt or deferred laser, followed by pro re nata (PRN) re-treatment. The following OCT biomarkers were evaluated: subfoveal neuroretinal detachment (SND) (defined as present (SND+) or absent (SND-)), hyperreflective retinal foci (HRF) number (defined as: absent/few(HRF-) or moderate/many (HRF+)), external limiting membrane (ELM) integrity, central macular thickness (CMT), and central retinal thickness (CRT). Changes in SND status and in the number of HRF were evaluated at each DME recurrence throughout the follow-up(FU) period. Mutual correlation among OCT biomarkers and their relationship with visual and anatomic outcomes were assessed both at baseline and over the FU period.

RESULTS

The mean FU was 71.2 months (SD 28.4; min. 12-max. 111). At baseline, the prevalence of SRD+ was 27.8% and a high number of HRF were detected in 41.4% of the eyes. A significant reduction in the number of HRF, CMT, CRT, and in the prevalence of SND was recorded in the post-loading phase (p-value <0.0001). In DME recurrences, the presence of SND+ and HRF+ was significantly more frequent in eyes with baseline SND+ and HRF+ compared to eyes presenting baseline SND- and HRF- (p-value <0.0001). No role of SND (p-value: 0.926) and HRF (p-value: 0.281) as baseline predictors of visual and anatomic outcomes was demonstrated, while a worse visual outcome was significantly correlated with a higher incidence of relapsing SND+ (p-value <0.0001) and HRF+ (p-value <0.0028) throughout the FU period.

CONCLUSION

In this study, SND and HRF were frequently present in DME recurrences with the same pattern exhibited at baseline, suggesting that these OCT biomarkers may characterize a specific pattern of DME that repeats over time. Moreover, the results suggested that the persistence and recurrence of SND and HRF may account for a decrease in visual function more than the baseline prevalence of these biomarkers. Further studies are required to confirm these findings.

LRG1 Expression Is Elevated in the Eyes of Patients with Neovascular Age-Related Macular Degeneration

Leucine-rich a-2-glycoprotein 1 (LRG1) is a candidate therapeutic target for treating the neovascular form of age-related macular degeneration (nvAMD). In this study we examined the expression of LRG1 in eyes of nvAMD patients. Choroidal neovascular membranes (CNVMs) from patients who underwent submacular surgery for retinal pigment epithelium-choroid graft transplantation were collected from 5 nvAMD patients without any prior intravitreal anti-VEGF injection, and from six patients who received intravitreal anti-VEGF injections before surgery. As controls free of nvAMD, retina sections were obtained from the eyes resected from a patient with lacrimal sac tumor and from a patient with neuroblastoma. CNVMs were immunostained for CD34, LRG1, and α-smooth muscle actin (α-SMA). Aqueous humor samples were collected from 58 untreated-naïve nvAMD patients prior to the intravitreal injection of anti-VEGF and 51 age-matched cataract control patients, and LRG1 concentration was measured by ELISA. The level of LRG1 immunostaining is frequently high in both the endothelial cells of the blood vessels, and myofibroblasts in the surrounding tissue of CNVMs of treatment-naïve nvAMD patients. Furthermore, the average concentration of LRG1 was significantly higher in the aqueous humor of nvAMD patients than in controls. These observations provide a strong experimental basis and scientific rationale for the progression of a therapeutic anti-LRG1 monoclonal antibody into clinical trials with patients with nvAMD.

Retrobulbar triamcinolone for inflammatory choroidal neovascularization in pregnancy

Background

Choroidal neovascularization (CNV) in pregnancy has rarely been described. A differential diagnosis between inflammatory, idiopathic, and myopic CNV may be challenging. Moreover, there is no consensus on management, and therapeutic options may be further limited by patient and physician concerns about potential risk to the fetus. Herein, we report a case of inflammatory CNV during pregnancy and describe a previously unreported management approach with retrobulbar triamcinolone injections.

Case presentation

A 36-year-old woman presented with vision loss and metamorphopsia in her right eye while 21 weeks pregnant. She was diagnosed with an inflammatory CNV based on the following multimodal imaging findings: a type 2 lesion with the “pitchfork sign” on OCT, along with the absence of tomographic signs of myopic CNV, and the presence on autofluorescence of multiple hyper-autofluorescent spots, interpreted as focal areas of inflammation at the level of the outer retina and inner choroid. The patient refused oral corticosteroids and any intravitreal injection therapies. Therefore, she was treated with two trans-Tenon’s retrobulbar injections of triamcinolone acetonide after explaining the procedure and acquiring consent. The treatment resulted in a regression of inflammatory signs and a reduction of neovascular activity. No adverse events occurred for the mother or the baby, neither during the pregnancy nor after delivery.

Conclusion

Inflammatory CNV may be rarely associated with pregnancy. The correct diagnosis is crucial to allow the consideration of all possible management options. To the best of our knowledge, this is the first reported case of treatment with retrobulbar triamcinolone injections. This may represent a suitable therapeutic option in the absence of any other therapeutic approaches.

Biocompatibility of a Conjugated Polymer Retinal Prosthesis in the Domestic Pig

The progressive degeneration of retinal photoreceptors is one of the most significant causes of blindness in humans. Conjugated polymers represent an attractive solution to the field of retinal prostheses, and a multi-layer fully organic prosthesis implanted subretinally in dystrophic Royal College of Surgeons (RCS) rats was able to rescue visual functions. As a step toward human translation, we report here the fabrication and in vivo testing of a similar device engineered to adapt to the human-like size of the eye of the domestic pig, an excellent animal paradigm to test therapeutic strategies for photoreceptors degeneration. The active conjugated polymers were layered onto two distinct passive substrates, namely electro-spun silk fibroin (ESF) and polyethylene terephthalate (PET). Naive pigs were implanted subretinally with the active device in one eye, while the contralateral eye was sham implanted with substrate only. Retinal morphology and functionality were assessed before and after surgery by means of in vivo optical coherence tomography and full-field electroretinogram (ff-ERG) analysis. After the sacrifice, the retina morphology and inflammatory markers were analyzed by immunohistochemistry of the excised retinas. Surprisingly, ESF-based prostheses caused a proliferative vitreoretinopathy with disappearance of the ff-ERG b-wave in the implanted eyes. In contrast, PET-based active devices did not evoke significant inflammatory responses. As expected, the subretinal implantation of both PET only and the PET-based prosthesis locally decreased the thickness of the outer nuclear layer due to local photoreceptor loss. However, while the implantation of the PET only substrate decreased the ff-ERG b-wave amplitude with respect to the pre-implant ERG, the eyes implanted with the active device fully preserved the ERG responses, indicating an active compensation of the surgery-induced photoreceptor loss. Our findings highlight the possibility of developing a new generation of conjugated polymer/PET-based prosthetic devices that are highly biocompatible and potentially suitable for subretinal implantation in patients suffering from degenerative blindness.

Subretinally injected semiconducting polymer nanoparticles rescue vision in a rat model of retinal dystrophy

Inherited retinal dystrophies and late-stage age-related macular degeneration, for which treatments remain limited, are among the most prevalent causes of legal blindness. Retinal prostheses have been developed to stimulate the inner retinal network; however, lack of sensitivity and resolution, and the need for wiring or external cameras, have limited their application. Here we show that conjugated polymer nanoparticles (P3HT NPs) mediate light-evoked stimulation of retinal neurons and persistently rescue visual functions when subretinally injected in a rat model of retinitis pigmentosa. P3HT NPs spread out over the entire subretinal space and promote light-dependent activation of spared inner retinal neurons, recovering subcortical, cortical and behavioural visual responses in the absence of trophic effects or retinal inflammation. By conferring sustained light sensitivity to degenerate retinas after a single injection, and with the potential for high spatial resolution, P3HT NPs provide a new avenue in retinal prosthetics with potential applications not only in retinitis pigmentosa, but also in age-related macular degeneration.

Subretinally injected semiconducting polymer nanoparticles rescue vision in a rat model of retinal dystrophy

Inherited retinal dystrophies and late-stage age-related macular degeneration, for which treatments remain limited, are among the most prevalent causes of legal blindness. Retinal prostheses have been developed to stimulate the inner retinal network; however, lack of sensitivity and resolution, and the need for wiring or external cameras, have limited their application. Here we show that conjugated polymer nanoparticles (P3HT NPs) mediate light-evoked stimulation of retinal neurons and persistently rescue visual functions when subretinally injected in a rat model of retinitis pigmentosa. P3HT NPs spread out over the entire subretinal space and promote light-dependent activation of spared inner retinal neurons, recovering subcortical, cortical and behavioural visual responses in the absence of trophic effects or retinal inflammation. By conferring sustained light sensitivity to degenerate retinas after a single injection, and with the potential for high spatial resolution, P3HT NPs provide a new avenue in retinal prosthetics with potential applications not only in retinitis pigmentosa, but also in age-related macular degeneration.

The Binding of CD93 to Multimerin-2 Promotes Choroidal Neovascularization

Purpose

The purpose of this study was to investigate the involvement of CD93 and Multimerin-2 in three choroidal neovascularization (CNV) models and to evaluate their contribution in the neovascular progression of age-related macular degeneration (AMD).

Methods

Choroidal neovascular membranes collected during surgery from AMD patients were analyzed by microscopy methods. Laser-induced CNV mouse models and choroid sprouting assays (CSAs) were carried out using the CD93 knockout mouse model. An original ex vivo CSA of vascular angiogenesis, employing choroid tissues isolated from human donors, was developed.

Results

In contrast to healthy choroid endothelium, hyperproliferative choroidal endothelial cells (ECs) of AMD patients expressed high levels of CD93, and Multimerin-2 was abundantly deposited along the choroidal neovasculature. CD93 knockout mice showed a significant reduced neovascularization after laser photocoagulation, and their choroidal ECs displayed a decreased ability to produce sprouts in ex vivo angiogenesis assays. Moreover, the presence of an antibody able to hamper the CD93/Multimerin-2 interaction reduced vascular sprouting in the human CSA.

Conclusions

Our results demonstrate that CD93 and its interaction with Multimerin-2 play an important role in pathological vascularization of the choroid, disclosing new possibilities for therapeutic intervention to neovascular AMD.

Scleral thinning surgery for bullous retinal detachment with retinal pigment epithelial tear in central serous chorioretinopathy: a case report

Background

Bullous serous retinal detachment (RD) with retinal pigment epithelial (RPE) tear is a rare and severe variant of chronic central serous chorioretinopathy (CSC). Due to its atypical presentation, it may raise diagnostic issues, leading to inappropriate therapeutic procedures. The optimum treatment for this CSC variant is still uncertain.

Case presentation

A 65-year-old male was referred for vitreo-retinal surgery with a provisional diagnosis of rhegmatogenous RD in his right eye. Dilated fundus examination showed an inferior bullous RD with no evidence of retinal breaks, while a large RPE tear was detected in the temporal quadrant. Ocular ultrasound showed no mass lesion. The axial length was 23.63 mm. Enhanced depth imaging optical coherence tomography (EDI-OCT) revealed a pachychoroid pattern in both eyes. The patient referred a history of CSC in the right eye and the recent use of intravenous corticosteroids for bronchitis. Laser therapy and photodynamic therapy were not applicable due to the extension and elevation of the RD. Two months after oral treatment with eplerenone, the subretinal fluid increased significantly. The patient underwent two 4 × 4 mm deep lamellar sclerectomies in the inferior quadrants. The surgical treatment resulted in complete RD resolution.

Conclusion

A correct diagnosis of bullous variant of chronic CSC with RPE tear is critical to avoid inappropriate procedures and to prevent severe visual loss as a result of neuroretinal damage. Scleral thinning surgery may be considered a valid option, resulting in rapid and long-lasting resolution of RD.

The porcine iodoacetic acid model of retinal degeneration: Morpho-functional characterization of the visual system

Porcine models of ophthalmological diseases are often used in pre-clinical translational studies due to pigs' similarities to humans. In particular, the iodoacetic acid (IAA) model of photoreceptor degeneration seems to mimic well the endstage phenotype of human pathologies as retinitis pigmentosa and age-related macular degeneration, with high potential for prosthesis/retinal devices testing. IAA is capable of inducing photoreceptor death by blockage of glycolysis, and its effects on the retina have been described. Nonetheless, up to date, literature lacks of a comprehensive morpho-functional characterization of the entire visual system of this model. This gap is particularly critical for prosthesis testing as inner retinal structures and optic pathways must be preserved to elicit cortical responses and restore vision. In this study, we investigated the functional and anatomical features of the visual system of IAA-treated pigs and compared them to control animals. IAA was administered intravenously at 12 mg/kg; control animals received saline solution (NaCl 0.9% w/v). Electrophysiological analyses included full-field (ffERGs) and pattern (PERGs) electroretinograms and flash visually evoked potentials (fVEPs). Histological evaluations were performed on the retina and the optic pathways and included thickness of the different retinal layers, ganglion cells count, and immunohistochemistry for microglial cells, macroglial cells, and oligodendrocytes. The histological results indicate that IAA treatment does not affect the morphology of the inner retina and optic pathways. Electrophysiology confirms the selective rod and partial cone degeneration, but is ambiguous as to the functionality of the optic pathways, seemingly preserved as indicated by the still detectable fVEPs. Overall, the work ameliorates the characterization of such rapid and cost-effective model, providing more strength and reliability for future pre-clinical translational trials.

Large Idiopathic Macular Hole Surgery: Remodelling of Outer Retinal Layers after Traditional Internal Limiting Membrane Peeling or Inverted Flap Technique

OBJECTIVE

To investigate the influence of the inverted flap technique compared with traditional internal limiting membrane (ILM) peeling in the postoperative remodelling of outer retinal layers of idiopathic macular holes (MHs) >450 µm.

METHODS

We analyzed medical records and imaging studies of all patients with an idiopathic MH >450 µm who underwent vitrectomy at the Sacco University Hospital, Milan, and the Sacro Cuore Don Calabria Hospital, Verona, Italy, between January 2008 and December 2017. Out of 41 eyes evaluated, 17 were treated with traditional ILM peeling and 24 with the inverted ILM flap technique. All patients underwent follow-up examinations every 3 months and all of them completed a final visit 12 months after surgery. Best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) parameters were evaluated at each visit. The main outcome measures were the postoperative recovery rate of the external limiting membrane (ELM) and ellipsoid zone (EZ), and postoperative BCVA. Correlations between OCT measurements and visual outcome were analyzed.

RESULTS

The ELM recovery rate in the ILM peeling group (15/17 eyes, 88%) was higher than in the ILM flap group (14/24 eyes, 58%) (p = 0.079). The EZ recovery rate was similar in the 2 groups, 7/17 eyes (41%) in the ILM peeling and 8/24 eyes (33%) in the ILM flap group (p = 0.744). Eyes without a persistent hyper-reflective "plug" at the edges of the MH showed a significantly higher EZ recovery rate (11/18, 61%) compared with eyes showing a persistent plug (4/23, 17%) (p = 0.008). The mean BCVA improved significantly in both groups: from 0.93 logMAR (20/170) to 0.26 logMAR (20/36) in the ILM peeling and from 0.98 logMAR (20/190) to 0.37 logMAR (20/46) in the ILM flap group. The final BCVA tended to be better in the ILM peeling group (p = 0.085).

CONCLUSIONS

Given the limited information about the influence of ILM flap versus traditional ILM peeling in the postoperative remodelling of large idiopathic MHs, our data provides some new insights into the healing process of MHs >450 µm. This should be considered as part of the decision process about whether to perform an ILM flap in these patients.

Intravitreal Recombinant Tissue Plasminogen Activator and Sulphur Hexafluoride Gas for Submacular Haemorrhage Displacement in Age-Related Macular Degeneration: Looking behind the Blood

PURPOSE

To evaluate the effectiveness of recombinant tissue plasminogen activator (rtPA) and sulphur hexafluoride gas (SF6) intravitreal injection for the displacement of large submacular haemorrhages (SMH) secondary to neovascular age-related macular degeneration and for guiding the selection of additional treatments or observations for choroidal neovascularization (CNV).

METHODS

The medical records of consecutive patients with recent-onset, large SMH, treated at Sacro Cuore Hospital from January 2004 to May 2016, were retrospectively analysed. All eyes underwent a 0.05-mL intravitreal injection of 50 μg rtPA, 0.3 mL of 100% SF6, and then face-down positioning. Afterwards, the eyes received additional treatments for CNV or observation, based on the severity and extent of the underlying pathology. The multimodal imaging features revealed after blood displacement were analysed and then correlated to the treatment selected as a second therapeutic option.

RESULTS

A total of 96 eyes met the inclusion criteria and was evaluated in this study. SMH was displaced from the fovea in the majority of the eyes (76%), allowing several diagnostic tools to evaluate the underlying macular features. In 19 cases (19.8%) exhibiting severe macular damage, no additional treatment was applied. In the remaining eyes, subsequent treatments included anti-vascular endothelial growth factor injections (44.8%), photodynamic therapy (n = 2), and submacular surgery (35.4%). Statistically significant correlations were found between the macular findings revealed after blood displacement and the additional treatments or observations selected for the underlying disease. The mean follow-up was 35 months. Improvements in visual acuity were statistically significant up to 3 years.

CONCLUSION

Intravitreal rtPA and gas injection was found to be effective for the displacement of large SMH, allowing postoperative diagnostic testing, and thus guiding the opportunity to apply further treatments. The addition of subsequent individualized treatments may allow long-term visual gain in selected cases.

Morphological changes in the diseased retina on a healthy choroid-retinal pigment epithelial complex after full macular translocation for exudative age-related macular degeneration

PURPOSE

To describe the change in the retinal morphology after full macular translocation (FMT) for exudative age-related macular degeneration (AMD) and identify predictive factors for the visual outcome.

METHODS

All patients who underwent FMT from December 2008 through July 2013 were selected. Exclusion criteria were FMT for other disease than AMD, age <60 years, <12 months of follow-up or no available images. Spectral domain optical coherence tomography, fundus autofluorescence, fluorangiography and indocyanine green angiography were evaluated.

RESULTS

In total, 51 patients were included with a mean follow-up of 30 months. The presence of the external limiting membrane (ELM) was a significant predictor for a favourable visual outcome 1 year after FMT (OR = -0.30). Other significant predictive factors were the absence of intraretinal fluid (OR = 0.28) and the mixed choroidal neovascularization type (OR = -0.47), whereas nonresponders (OR = 0.41) and fibrotic lesions (OR = 0.35) were less likely to have a good visual function after surgery.

CONCLUSION

Full macular translocation (FMT), that permits to relocate the diseased macula onto an area of unaffected retinal pigment epithelial and choroid, can restore the anatomy and visual function in some patients with AMD when the outer retina layers are not irreversibly damaged. The presence of the ELM seems to be the most reliable factor in predicting the functional outcome.

Blame It on the Metabolite: 3,5-Dichloroaniline Rather than the Parent Compound Is Responsible for the Decreasing Diversity and Function of Soil Microorganisms

Pesticides are key stressors of soil microorganisms with reciprocal effects on ecosystem functioning. These effects have been mainly attributed to the parent compounds, while the impact of their transformation products (TPs) has been largely overlooked. We assessed in a meadow soil (soil A) the transformation of iprodione and its toxicity in relation to (i) the abundance of functional microbial groups, (ii) the activity of key microbial enzymes, and (iii) the diversity of bacteria, fungi, and ammonia-oxidizing microorganisms (AOM) using amplicon sequencing. 3,5-Dichloroaniline (3,5-DCA), the main iprodione TP, was identified as a key explanatory factor for the persistent reduction in enzymatic activities and potential nitrification (PN) and for the observed structural changes in the bacterial and fungal communities. The abundances of certain bacterial (Actinobacteria, Hyphomicrobiaceae, Ilumatobacter, and Solirubrobacter) and fungal (Pichiaceae) groups were negatively correlated with 3,5-DCA. A subsequent study in a fallow agricultural soil (soil B) showed limited formation of 3,5-DCA, which concurred with the lack of effects on nitrification. Direct 3,5-DCA application in soil B induced a dose-dependent reduction of PN and NO3--N, which recovered with time. In vitro assays with terrestrial AOM verified the greater toxicity of 3,5-DCA over iprodione. "Candidatus Nitrosotalea sinensis" Nd2 was the most sensitive AOM to both compounds. Our findings build on previous evidence on the sensitivity of AOM to pesticides, reinforcing their potential utilization as indicators of the soil microbial toxicity of pesticides in pesticide environmental risk analysis and stressing the need to consider the contribution of TPs in the toxicity of pesticides on the soil microbial community.IMPORTANCE Pesticide toxicity on soil microorganisms is an emerging issue in pesticide risk assessment, dictated by the pivotal role of soil microorganisms in ecosystem services. However, the focus has traditionally been on parent compounds, while transformation products (TPs) are largely overlooked. We tested the hypothesis that TPs can be major contributors to the soil microbial toxicity of pesticides using iprodione and its main TP, 3,5-dichloroaniline, as model compounds. We demonstrated, by measuring functional and structural endpoints, that 3,5-dichloroaniline and not iprodione was associated with adverse effects on soil microorganisms, with nitrification being mostly affected. Pioneering in vitro assays with relevant ammonia-oxidizing bacteria and archaea verified the greater toxicity of 3,5-dichloroaniline. Our findings are expected to advance environmental risk assessment, highlighting the potential of ammonia-oxidizing microorganisms as indicators of the soil microbial toxicity of pesticides and stressing the need to consider the contribution of TPs to pesticide soil microbial toxicity.

Assessment of the impact of three pesticides on microbial dynamics and functions in a lab-to-field experimental approach

The toxicity of pesticides on soil microorganisms is as an emerging area of concern. Novel and well-standardized tools could be now used to provide a robust assessment of the ecotoxicity of pesticides on soil microorganisms. We followed a tiered lab-to-field approach to assess the toxicity of three pesticides, widely used at EU level, (chlorpyrifos (CHL), isoproturon (IPU) and tebuconazole (TBZ)) on (i) the abundance of 11 microbial taxa and 8 functional microbial groups via q-PCR and (ii) the activity of enzymes involved in biogeochemical cycles via fluorometric analysis. Correlation of microbial measurements with the concentration of pesticides, and their transformation products (TPs) in soil enabled the identification of the compounds driving the effects observed. At lab tests (×1, ×2 and ×10 the recommended dose), CHL and TBZ significantly reduced the relative abundance of ammonia-oxidizing bacteria (AOB) and archaea (AOA) which recovered by the end of the study, while all pesticides induced a persistent reduction in the relative abundance of sulfur-oxidizing bacteria (SOB). The two demethylated metabolites of IPU (MD-IPU and DD-IPU) adversely affected P-cycling enzymes and leucine aminopeptidase (Leu). At field tests (×1, ×2 and ×5 the recommended dose), a persistent reduction on the relative abundance of AOA was induced by all pesticides, but only CHL and its hydrolysis product 3,5,6 trichloro-2-pyridynol (TCP) soil levels were negatively correlated with AOA relative abundance. Our findings suggest that ammonia-oxidizing microorganisms constitute the most responsive microbial group to pesticides and could be potential candidates for inclusion in pesticide risk assessment.

Choroidal perfusion abnormalities associated with Acute Posterior Multifocal Placoid Pigment Epitheliopathy: a case report

Background

Indocyanine Green Angiography (ICG-A) and Enhanced Depth Imaging Spectral-Domain Optical Coherence Tomography (EDI-OCT) are essential imaging techniques for diagnosis, management and understanding of the pathophysiology of many chorioretinal diseases. Herein, we report the ICG-A and EDI-OCT findings from a case of Acute Posterior Multifocal Placoid Pigment Epitheliopathy (APMPPE), in which these imaging techniques enable the visualization of more diagnostic details than those observable with other widely used diagnostic tools.

Case presentation

A 60-year-old white female presented with bilateral blurred vision for few days. Fundus examination showed multiple, yellow-white placoid lesions at the posterior pole of both eyes. The placoid lesions were also evident on Spectral-Domain Optical Coherence Tomography (SD-OCT), Fluorescein Angiography (FA), Fundus Autofluorescence (AF), and ICG-A. A complete ophthalmologic examination was performed and the diagnosis of APMPPE was made based on imaging and clinical features. Notably, all the lesions detected by FA, AF and OCT corresponded to focal areas of hypofluorescence seen on ICG-A, whereas several additional hypofluorescent areas that were not associated with FA, AF or OCT abnormalities, were also detected with ICG-A. On follow-up, the regression of outer retinal abnormalities detected on OCT preceded the restoration of choroidal perfusion abnormalities in the corresponding locations on ICG-A. This long-standing choroidal perfusion defect could not be detected with OCT. EDI-OCT scans revealed characteristic choriocapillaris changes beneath the placoid lesions and an increase in choroidal thickness during the acute phase, with subsequent decrease in the inactive stage of the disease.

Conclusion

Our findings show that ICG-A and EDI-OCT provide detailed morphologic information of choroidal abnormalities in APMPPE and allow accurate evaluation of definitive resolution of the lesions. Moreover, they support the acute choroidal hypoperfusion as the primary mechanism overlying the pathogenesis of the disease, and suggest that the non-perfused areas may extend beyond the damage of the outer retina.

A fully organic retinal prosthesis restores vision in a rat model of degenerative blindness

The degeneration of photoreceptors in the retina is one of the major causes of adult blindness in humans. Unfortunately, no effective clinical treatments exist for the majority of retinal degenerative disorders. Here we report on the fabrication and functional validation of a fully organic prosthesis for long-term in vivo subretinal implantation in the eye of Royal College of Surgeons rats, a widely recognized model of retinitis pigmentosa. Electrophysiological and behavioural analyses reveal a prosthesis-dependent recovery of light sensitivity and visual acuity that persists up to 6-10 months after surgery. The rescue of the visual function is accompanied by an increase in the basal metabolic activity of the primary visual cortex, as demonstrated by positron emission tomography imaging. Our results highlight the possibility of developing a new generation of fully organic, highly biocompatible and functionally autonomous photovoltaic prostheses for subretinal implants to treat degenerative blindness.

Vitreomacular Adhesion and the Risk of Neovascular Age-Related Macular Degeneration

PURPOSE

To assess the prevalence of vitreomacular adhesion (VMA) in consecutive naïve eyes diagnosed with exudative age-related macular degeneration (AMD) in comparison with eyes with nonexudative AMD and age-matched controls, and to evaluate prospectively the incidence of vitreomacular interface changes over time and their influence on choroidal neovascularization (CNV) development.

DESIGN

Retrospective cross-sectional analysis and longitudinal cohort study conducted at Sacrocuore Hospital, Negrar, Verona, Italy.

PARTICIPANTS

A total of 1067 eyes examined at Sacrocuore Hospital between August 2008 and June 2015 met the inclusion criteria and were evaluated in this study.

METHODS

Eyes were classified into 3 groups: 403 eyes of 364 patients (mean [standard deviation; SD] age 77.8 [8.0] years) affected by exudative AMD; 350 eyes of 298 subjects (mean [SD] age 78.1 [8.2] years) with nonexudative AMD; and 314 eyes of 214 subjects (mean [SD] age 74.2 [8.2] years) with no signs of AMD enrolled as the control group. The vitreomacular interface status was evaluated by spectral-domain optical coherence tomography (OCT) and was graded according to the OCT-based International Classification System developed by the International Vitreomacular Traction Study Group by 2 independent masked observers.

RESULTS

VMA was present in 101 (25.1%) eyes with exudative AMD, 84 (24.0%) eyes with nonexudative AMD, and 84 (26.8%) eyes with no signs of AMD (no statistical difference was found; P = 0.3384). Spontaneous release of VMA (RVMA) was found in 15 (15.3%) eyes with exudative AMD, 21 (28.0%) eyes with nonexudative AMD, and 10 (24.4%) eyes with no signs of AMD over a mean follow-up of 25.5, 25.9, and 24.1 months, respectively. The incidence of RVMA in exudative AMD eyes was significantly lower compared with nonexudative (P = 0.0207) and lower, but not statistically significant, with respect to eyes with no signs of AMD (P = 0.1013). In eyes with nonexudative AMD, de novo development of CNV occurred in 91 eyes (30.6%). There was no significant difference regarding the rate of CNV development in the presence or absence of VMA (P = 0.0966).

CONCLUSIONS

The present study found no significant difference in the prevalence of VMA in eyes affected by AMD compared with age-matched controls and no difference in the rate of de novo CNV development in eyes with or without VMA. Conversely, a lower incidence of RVMA over time was found in eyes affected by exudative AMD. The results of this study suggest that VMA might be a consequence rather than a causative factor in the development of CNV.

Characterization of a Polymer-Based, Fully Organic Prosthesis for Implantation into the Subretinal Space of the Rat

Replacement strategies arise as promising approaches in case of inherited retinal dystrophies leading to blindness. A fully organic retinal prosthesis made of conjugated polymers layered onto a silk fibroin substrate is engineered. First, the biophysical and surface properties are characterized; then, the long-term biocompatibility is assessed after implantation of the organic device in the subretinal space of 3-months-old rats for a period of five months. The results indicate a good stability of the subretinal implants over time, with preservation of the physical properties of the polymeric layer and a tight contact with the outer retina. Immunoinflammatory markers detect only a modest tissue reaction to the surgical insult and the foreign body that peaks shortly after surgery and progressively decreases with time to normal levels at five months after implantation. Importantly, the integrity of the polymeric layer in direct contact with the retinal tissue is preserved after five months of implantation. The recovery of the foreign-body tissue reaction is also associated with a normal b-wave in the electroretinographic response. The results demonstrate that the device implanted in nondystrophic eyes is well tolerated, highly biocompatible, and suitable as retinal prosthesis in case of photoreceptor degeneration.

Multimodal imaging findings in a case of severe Central Serous Chorioretinopathy in an uncomplicated pregnancy

Background

Central Serous Chorioretinopathy (CSC) has been previously reported as an infrequent complication of pregnancy that usually resolves spontaneously after delivery, with minimal or no sequel. We report a case of a severe form of CSC in an uncomplicated pregnancy with extensive subfoveal exudates and severe permanent visual loss. Multimodal imaging techniques, including color and red-free photographs, near-infrared reflectance, fluorescein angiography, and spectral-domain optical coherence tomography, were performed and the findings were correlated to the changes in visual acuity.

Case presentation

A 35-year-old pregnant woman presented with loss of vision and metamorphopsia in her left eye. Fundus examination showed subfoveal severe exudation with a posterior pole serous detachment. Optical coherence tomography (OCT) showed macular neurosensory detachment with central highly reflective sub-retinal material. Multimodal fundus pictures and angiograms revealed distinct clinical features of the disease during both the acute and final phase. The disease spontaneously resolved after delivery with regression of the subretinal fluid and the disappearance of subfoveal exudates. Nevertheless, because of severe atrophic macular changes and subfoveal fibrosis, no improvement of visual acuity was noted.

Conclusion

Severe variants of CSC may also present in cases of uncomplicated pregnancy and result in a poor prognosis. Recognising these presentations of CSC is critical to avoid improper management. Multimodal imaging may help to clarify the diagnosis and highlight the clinical features.

Uveal effusion syndrome mimicking severe chronic posterior uveitis: a case series of seven eyes of four patients

PURPOSE

To describe the clinical findings and management of eyes affected by uveal effusion syndrome (UES) presenting with clinical features mimicking inflammatory ocular diseases, treated using individualized surgical approaches.

METHODS

We report a consecutive interventional case series of seven eyes of four patients affected by UES. On presentation in our clinic, all patients showed signs of steroid effects as a consequence of a presumptive diagnosis; one eye had undergone vitrectomy for retinal detachment (RD), without benefit. Diagnosis of UES was based on ophthalmic examination, ultrasonography, fluorescein angiography, biometry and magnetic resonance imaging. Five eyes with active disease were treated using scleral thinning surgical procedures based on the extent and characteristics of the disease: sclerectomy sites were ultrasound-guided to the area of maximal choroidal swelling, associated with evacuative puncture in the case of bilateral funnel-shaped RD.

RESULTS

One patient was diagnosed with type 1 UES, two with type 2, and one with type 3. Mean postoperative follow-up was 26 months. In all eyes, surgery resolved the ciliochoroidal and retinal detachment and improved visual acuity. In two eyes, visual restoration was limited by a prolonged disease course.

CONCLUSION

UES may be mistaken for other sources of ciliochoroidal effusion. Early diagnosis and treatment is critical to avoid unnecessary procedures and to prevent severe visual loss as a result of neuroretinal damage. Surgical treatment based on the extent and characteristics of the disease may be effective for the resolution of ciliochoroidal effusion, even in type 3 UES, where conventional surgery has proved unsuccessful.

Long-Term Results of Full Macular Translocation for Choroidal Neovascularization in Age-Related Macular Degeneration

PURPOSE

To investigate the long-term outcome of full macular translocation (FMT) for neovascular age-related macular degeneration (AMD) and to identify predictive factors.

DESIGN

Retrospective, uncontrolled case series.

PARTICIPANTS

Patients were considered for FMT if they had low vision in the fellow eye and choroidal neovascularization (CNV) along with (1) no response to vascular endothelial growth factor (VEGF) inhibitors, (2) retinal pigment epithelium (RPE) tear, (3) subretinal hemorrhage, (4) foveal scar tissue of recent onset, or (5) CNV before the availability of VEGF inhibitors. From 2004 through 2012, a total of 255 patients underwent FMT. Exclusion criteria were patients younger than 60 years, FMT for disease other than AMD, and a follow-up of less than 12 months.

METHODS

Preoperative, annual, and last distance best-corrected visual acuity (BCVA) were obtained retrospectively from patient files. Complications were recorded using funduscopy, optical coherence tomography, autofluorescence, and angiography.

MAIN OUTCOME MEASURES

Distance BCVA at 1 year and 5 years after surgery and at last visit compared with preoperative BCVA.

RESULTS

One hundred fifty-eight patients (mean follow-up, 45 months) were included. Median BCVA improved from 0.90 logarithm of the minimum angle of resolution (logMAR) before surgery to 0.70 logMAR 1 year after FMT (2 lines gained; P = 0.000). In a subgroup of 56 patients followed up for 5 years or more, median BCVA improved from 0.95 logMAR before surgery to 0.70 logMAR 1 year after surgery, and remained improved 5 years after FMT with a median BCVA of 0.80 logMAR (1.5 lines gained compared with preoperative BCVA; P = 0.000). The main complications were foveal RPE atrophy (n = 73; 47%) and CNV recurrence (n = 47; 30%). Foveal RPE atrophy (odds ratio [OR], 7.0), CNV recurrence (OR, 2.6), and proliferative vitreoretinopathy (PVR; OR, 17.6) were statistically significant predictors (P < 0.05) for losing 1 line or more at last visit.

CONCLUSIONS

In this study, BCVA was improved up to 5 years after FMT. Foveal RPE atrophy, CNV recurrence, and PVR carried a worse prognosis. In patients who are unlikely to benefit from VEGF inhibitors, FMT can be considered for second eyes with neovascular AMD.

A polymer optoelectronic interface restores light sensitivity in blind rat retinas

Interfacing organic electronics with biological substrates offers new possibilities for biotechnology due to the beneficial properties exhibited by organic conducting polymers. These polymers have been used for cellular interfaces in several fashions, including cellular scaffolds, neural probes, biosensors and actuators for drug release. Recently, an organic photovoltaic blend has been exploited for neuronal stimulation via a photo-excitation process. Here, we document the use of a single-component organic film of poly(3-hexylthiophene) (P3HT) to trigger neuronal firing upon illumination. Moreover, we demonstrate that this bio-organic interface restored light sensitivity in explants of rat retinas with light-induced photoreceptor degeneration. These findings suggest that all-organic devices may play an important future role in sub-retinal prosthetic implants.

Lamellar macular hole: a clinicopathologic correlation of surgically excised epiretinal membranes

PURPOSE

To correlate clinical and optical coherence tomographic (OCT) features with morphologic and immunohistochemical findings of epiretinal membranes (ERMs) in lamellar macular holes (LMHs).

METHODS

Nineteen specimens were removed from 19 eyes during vitrectomy for lamellar macular hole with ERM and internal limiting membrane peeling, and were processed for transmission electron microscopy and immunohistochemistry by cross-sectional and flat-mount preparation techniques. By using OCT criteria and intraoperative observations, ERM specimens were divided into two groups: 13 "dense" and 6 "tractional" membranes. Patients' records were reviewed.

RESULTS

"Dense" ERMs were seen with abundant clusters of fibrous long-spacing collagen embedded in compactly folded native vitreous collagen strands. Posterior hyaloids were attached to the retina in the majority of cases. Both groups of ERMs showed positive immunoreactivity for glial fibrillic acidic protein and hyalocyte markers. Anti-α-smooth muscle actin labeling was most positive in "tractional" ERMs. Surgery resulted in significant improvement (74%) of visual acuity, with a mean gain of 2 Snellen lines in both groups. All other patients (26%) preserved vision. Three patients (16%) developed a full-thickness macular defect requiring additional surgery.

CONCLUSIONS

Morphologic components differ in epiretinal cell proliferations of LMHs. In association with degradation of vitreous collagen, glial cells and hyalocytes seem to play an important role in LMH development. Since functional benefit after surgery was limited and progression to a full-thickness macular defect was a notable complication, we recommend caution in proceeding with surgical intervention. Further investigations are needed to elucidate whether "dense" and "tractional" LMHs represent different disease entities or different stages of one disorder.

Early perfusion of a free RPE-choroid graft in patients with exudative macular degeneration can be imaged with spectral domain-OCT

PURPOSE

To study early flow and revascularization in a free, autologous, retinal pigment epithelium (RPE)-choroid graft.

METHODS

This prospective cohort study used spectral domain-optical coherence tomography (SD-OCT) after RPE-choroid graft surgery in 12 patients. This SD-OCT was combined with fluorescein angiography (FA) and indocyanine green angiography (ICGA) in 5 patients.

RESULTS

SD-OCT revealed that vessel diameter, number of vessels, and graft thickness increased in 10 of 12 patients, starting between 3 and 10 days after surgery. A subsequent decrease in thickness was found in all 10 patients, beginning as early as 8 days after surgery. Initially, the graft vessels were optically clearer than the underlying choroidal recipient vessels. Between 8 and 30 days after surgery, the optically clear vessels became gray, similar to the recipient choroid. FA and ICGA revealed perfusion in 4 of 5 patients between postoperative days 6 and 15. Between postoperative days 12 and 60, the entire choroidal structure of the graft was visible on ICGA. CONCLUSIONS; These data suggest that enlargement of vessel diameter, increase in the number of choroidal vessels, and graft thickening visualized by SD-OCT correspond with the ingrowth of afferent vessels, as demonstrated by ICGA. The subsequent establishment of efferent vessels results in flow, imaged as a change in color of the graft's vessels from optically clear to gray, graft thinning on SD-OCT, and complete revascularization on ICGA. SD-OCT, a noninvasive examination, can be used to demonstrate early graft perfusion in patients (trialregister.nl/trialreg/admin/rctview.asp number, NTR1768).

1000 cSt silicone oil vs heavy silicone oil as intraocular tamponade in retinal detachment associated to myopic macular hole

BACKGROUND

Several surgical techniques have been described for the treatment of retinal detachment (RD) associated to myopic macular hole (MMH). In this retrospective study, the anatomical and functional outcomes of pars plana vitrectomy (PPV) with long-term tamponade, using either 1000 cSt silicone oil (SO) or heavy silicone oil (HSO), are compared.

METHODS

Forty-two eyes affected by RD associated with MMH were included. The surgical technique involved standard 3-port 20-gauge PPV with long-term tamponade. The patients were divided into two groups, according to the intraocular tamponade: SO in group 1 (n = 17), and HSO in group 2 (n = 25). Internal limiting membrane (ILM) removal was performed in 15 cases of group 1 and 20 cases of group 2. Tamponade removal was performed 2 to 5 months after primary surgery. The patients were assessed 1 week and 1 month after primary surgery, and then 1 week and 1 month after tamponade removal or after further surgery if macular redetachment had occurred. The patients were also visited every 2 months for at least 1 year after final tamponade removal. Follow-up was considered closed at 1 year after final tamponade removal.

RESULTS

Preoperative best-corrected visual acuity (BCVA), expressed as LogMar, was 2.8 ± 0.77 for group 1 and 2.1 ± 0.94 for group 2. At the last visit, the BCVA was 1.41 ± 0.96 and 1.48 ± 0.77 for groups 1 and 2 respectively. Retinal reattachment was achieved with one operation in 13 eyes of group 1 (76.5%) and 18 of group 2 (81.8%) (P = 0.69). The average number of surgery needed to achieve retinal attachment by patients of group 1 and 2 was respectively 1.36 ± 0.63 and 1.46 ± 0.59 (P = 0.77). Five patients of group 1 and four of group 2 developed a chronic glaucoma (P = 0.238).

CONCLUSIONS

PPV with ILM peeling and long-term tamponade was demonstrated to be a good surgical option to treat RD due to MMH; SO and HSO seemed to be equally effective, although the success rates remained far from an ideal 100%.