Surgery of cicatricial stage of choroidal neovascular membrane with autologous conditioned plasma

Purpose. To estimate the effectiveness of the cicatricial stage of choroidal neovascular membrane (CNM) surgery with retina fixation after retinotomy of paracentral areas with autologous conditioned platelet rich plasma (ACP) and without endolaser photocoagulation and silicone oil tamponade. Material and methods. 17 CNM patients aged 49 to 82 with visual acuity from 0.02 eccentric to 0.08 were operated. The operation consisted in 25-, 27+-gauge vitrectomy, removal of the posterior hyaloid membrane and the inner limiting membrane (in the presence of an epiretinal membrane), paracentral retinotomy, removal of the choroidal neovascular membrane via retinotomy, pneumoretinopexy, 2–3 layer instillation of ACP in the retinotomy area without endolaser photocoagulation and silicone oil tamponade, seamless closure of sclera- and conjunctivotomy with a layer of autologous conditioned plasma. Results. Full retinal reattachment and closure of the retinotomy opening in the late postoperative period was noted in all patients. No case of recurrent retinal detachment was recorded. Complete closure of sclera- and conjunctivotomy with no additional suture fixation was achieved in all cases. In the long-term period after the removal of the cicatricial choroidal membrane, visual acuity was 0.03–0.2. Conclusion. The modern surgery of the cicatricial stage of CNM using ACP to close the retinotomy defect after removal of cicatricial CNV without endolaser coagulation of the retina and silicone tamponade, followed by seamless blocking of the sclero- and conjunctivotomy with ACP produces excellent anatomical and functional results, minimizing the risk of postoperative complications.

New technique for removal of perfluorocarbon liquid related sticky silicone oil and literature review

AIM: To investigate the safety and efficacy of sticky silicone oil (SSO) removal using a 22-gauge vein detained needle and inner limiting membrane (ILM) wrap-and-peel technique. METHODS: This retrospective consecutive case series reviewed the records of patients with a history of retinal detachment who had received silicone oil and perfluorocarbon liquid (PFCL) as intraocular tamponades. Patients were included in the analysis if they exhibited SSO remnants during silicone oil removal. The aspiration of most of the SSO remnants was performed by a 22-gauge vein detained needle. The small amounts of droplets adhered to the macula and epi-macular membrane were subsequently removed by the ILM warp-and-peel technique. The anatomical and functional outcomes, and postoperative complications were recorded. In vitro experiments were performed to simulate the formation of SSO remnants in four groups. RESULTS: Of 711 patients who underwent silicone oil removal during the study period, 9 patients exhibited SSO remnants and underwent follow-up for at least 3mo. Seven eyes (78%) underwent the ILM wrap-and-peel technique to completely remove small droplets of SSO that were glued to the macula and epi-macular membrane. No obvious complications occurred. Postoperative optical coherence tomography revealed normal retinal structure in all patients. In vitro analyses showed that balanced salt solution and prolonged vibration (for 1wk) had the strongest effects on silicone oil and PFCL compound opacities. CONCLUSION: SSO remnants could be removed in an intact manner and without complications, using a vein detained needle-assisted and ILM wrap-and-peel technique. The findings suggest that PFCL and infusion fluid should be completely removed before silicone oil injection to prevent SSO formation.

Segmentation of Preretinal Space in Optical Coherence Tomography Images Using Deep Neural Networks

This paper proposes an efficient segmentation of the preretinal area between the inner limiting membrane (ILM) and posterior cortical vitreous (PCV) of the human eye in an image obtained with the use of optical coherence tomography (OCT). The research was carried out using a database of three-dimensional OCT imaging scans obtained with the Optovue RTVue XR Avanti device. Various types of neural networks (UNet, Attention UNet, ReLayNet, LFUNet) were tested for semantic segmentation, their effectiveness was assessed using the Dice coefficient and compared to the graph theory techniques. Improvement in segmentation efficiency was achieved through the use of relative distance maps. We also show that selecting a larger kernel size for convolutional layers can improve segmentation quality depending on the neural network model. In the case of PVC, we obtain the effectiveness reaching up to 96.35%. The proposed solution can be widely used to diagnose vitreomacular traction changes, which is not yet available in scientific or commercial OCT imaging solutions.

Lamellar Hole-associated Epiretinal Proliferation in choroideremia: a case report

Background To report a clinical case of a patient affected with choroideremia (CHM) who underwent macular surgery for a macular hole (MH) with Lamellar Hole-associated Epiretinal Proliferation (LHEP). Case presentation We have described a 48-year-old male patient affected with CHM who developed MH with LHEP over a 7-year follow-up. The patient was referred to the Regional Center for Hereditary Retinal Degenerations of the Eye Clinic in Florence (Italy) in April 2012. The patient underwent vitrectomy and Inner Limiting Membrane (ILM) and LHEP peeling with fluid-air exchange. Ultra-structural examination of the excised epiretinal proliferation, carried out using electron microscopy, showed dense amorphous material, mainly composed of abundant clusters of fibrous collagens resembling compact fibrous long spacing collagen (FLSC), embedded in native vitreous collagen (NVC) and type IV collagen. No cells were detected in any of the specimens collected. At the 3rd-week postoperative follow-up the macular hole was closed. Conclusion Macular hole with LHEP can be detected in CHM patients; in our patient the macular hole showed tractional and degenerative features, with good anatomical results after macular surgery.

Automatic Segmentation and Visualisation of the Epirretinal Membrane in OCT Scans Using Densely Connected Convolutional Networks

The Epiretinal Membrane (ERM) is an ocular disease that appears as a fibro-cellular layer of tissue over the retina, specifically, over the Inner Limiting Membrane (ILM). It causes vision blurring and distortion, and its presence can be indicative of other ocular pathologies, such as diabetic macular edema. The ERM diagnosis is usually performed by visually inspecting Optical Coherence Tomography (OCT) images, a manual process which is tiresome and prone to subjectivity. In this work, we present a methodology for the automatic segmentation and visualisation of the ERM in OCT volumes using deep learning. By employing a Densely Connected Convolutional Network, every pixel in the ILM can be classified into either healthy or pathological. Thus, a segmentation of the region susceptible to ERM appearance can be produced. This methodology also produces an intuitive colour map representation of the ERM presence over a visualisation of the eye fundus created from the OCT volume. In a series of representative experiments conducted to evaluate this methodology, it achieved a Dice score of 0.826±0.112 and a Jaccard index of 0.714±0.155. The results that were obtained demonstrate the competitive performance of the proposed methodology when compared to other works in the state of the art.

Deep-learning based retinal fluid segmentation in optical coherence tomography images using a cascade of ENets

Optical coherence tomography (OCT) is a non-invasive, painless and reproducible examination which allows ophthalmologists to visualize retinal layers. This imaging modality is useful to detect diseases such as diabetic macular edema (DME) or age related macular degeneration (AMD), which are associated with fluid accumulations. In this paper, a cascade of deep convolutional neural networks is proposed using ENets for the segmentation of fluid accumulations in OCT B-Scans. After denoising the B-Scans, a first ENet extracts the region of interest (ROI) between the inner limiting membrane (ILM) and the Bruch's membrane (BM), whereas the second ENet segments the fluid in the ROI. A random forest classifier was applied on the segmented fluid regions to reject false positive. Our framework was trained on three different datasets with several diseases such as diabetic retinopathy (DR) and AMD. Our method achieves an average Dice Score for fluid segmentation of 0.80, 0.83 and 0.83 on the UMN DME, UMN AMD and Kermany datasets respectively.

Analysis of the efficacy of endovitreal surgery with the internal limiting membrane removal in patients with X-linked congenital retinoschisis

Purpose of this article is to analyze the effectiveness of endovitreal surgery with removal of the internal limiting membrane in patients with X-linked congenital retinoschisis. Material and methods. Three male patients underwent a standard 25 G vitrectomy with staining and removal of the internal limiting membrane in the macular zone and pneumoretinopexy. Results. All operations were uneventful. Stabilization of the pathological process was noted during the study period. Conclusion. Endovitreal surgery with the removal of the inner limiting membrane in the macular zone stabilizes the progression of X-linked congenital retinoschisis. Key words: retinoschisis, internal limiting membrane, endovitreal surgery.

The SD-OCT Characteristics After 577nm Laser Membranotomy of Sub-inner Limiting Membrane Hemorrhage

Background We investigate the SD-OCT features of sub-inner limiting membrane (sub-ILM) hemorrhage after 577nm laser membranotomy. Methods The ocular fundus photography and SD-OCT of patients who received 577nm laser membranotomy for sub-ILM hemorrhage were assessed from January 2017 to March 2021 in this retrospective cases series study. Results Total of 7 patients (7 eyes) were enrolled in this study, in which 3 were female and 4 were male. The SD-OCT of ILM after laser treatment showed two distinctive features: the ILM falling back to retina (4 cases) or persistent unsealed ILM which forming premacular cavity (3 cases). The SD-OCT of macular fovea after laser treatment showed three features: normal contour (3 cases), macular hole (1 cases) and epiretinal membrane (1 case). The outer retina showed “peg-like” or “patchy-like” structure on the site of ILM attached to retina.Conclusions 577nm laser is effective in treating of sub-ILM hemorrhage and SD-OCT is effective for diagnosis and following-up of sub-ILM hemorrhage.