Vitreoretinal Disorders Research Articles

Ultrastructural investigation of the posterior hyaloid membrane in posterior vitreous detachment.

Separation of the posterior hyaloid membrane (PHM) from the retina in posterior vitreous detachment (PVD) is a fundamental, but poorly understood, process underlying vitreoretinal disorders including retinal detachment and macular hole. We performed electron microscopy studies of the PHM after PVD to investigate its ultrastructure, associated cellular structures and relationship to the internal limiting membrane (ILM). Post-mortem human eyes were collected from recently deceased patients over 70 years of age. A posterior scleral button was trephined to identify PVD status, and the PHM and vitreous prepared for analysis with transmission and scanning electron microscopy. Twelve eyes from six patients were collected. Seven eyes had PVD; five eyes had attached vitreous. PHM was isolated from seven of seven eyes with PVD. The PHM in eyes with PVD is a laminar lacy sheet, distinct from the disorganised fibres of vitreous gel. Eyes without PVD had vitreous encased in internal limiting membrane which had separated en bloc from the retina. Cells embedded in the PHM (laminocytes) were identified in five of seven eyes with PVD, with strands stretching into the membrane. PHM isolated from eyes with PVD is distinct from artefactual separation of the ILM from the retina during dissection. PHM is ultrastructurally distinct from vitreous gel and is a separate entity. The en face appearance of PHM is similar to that of ILM, suggesting that in PVD, PHM forms from separation of an inner layer of ILM. Laminocytes may play a role in the pathogenesis of vitreoretinal disease.

TLR2 and TLR4 Are Expressed in Epiretinal Membranes: Possible Links with Vitreous Levels of Complement Fragments and DAMP-Related Proteins.

Previous studies reported the expression of toll-like receptors (TLRs), merely TLR2 and TLR4, and complement fragments (C3a, C5b9) in vitreoretinal disorders. Other than pathogens, TLRs can recognize endogenous products of tissue remodeling as damage-associated molecular pattern (DAMPs). The aim of this study was to confirm the expression of TLR2 and TLR4 in the fibrocellular membranes and vitreal fluids (soluble TLRs) of patients suffering of epiretinal membranes (ERMs) and assess their association with disease severity, complement fragments and inflammatory profiles. Twenty (n = 20) ERMs and twelve (n = 12) vitreous samples were collected at the time of the vitrectomy. Different severity-staged ERMs were processed for: immunolocalization (IF), transcriptomic (RT-PCR) and proteomics (ELISA, IP/WB, Protein Chip Array) analysis. The investigation of targets included TLR2, TLR4, C3a, C5b9, a few selected inflammatory biomarkers (Eotaxin-2, Rantes, Vascular Endothelial Growth Factor (VEGFA), Vascular Endothelial Growth Factor receptor (VEGFR2), Interferon-γ (IFNγ), Interleukin (IL1β, IL12p40/p70)) and a restricted panel of matrix enzymes (Matrix metalloproteinases (MMPs)/Tissue Inhibitor of Metallo-Proteinases (TIMPs)). A reduced cellularity was observed as function of ERM severity. TLR2, TLR4 and myD88 transcripts/proteins were detected in membranes and decreased upon disease severity. The levels of soluble TLR2 and TLR4, as well as C3a, C5b9, Eotaxin-2, Rantes, VEGFA, VEGFR2, IFNγ, IL1β, IL12p40/p70, MMP7 and TIMP2 levels were changed in vitreal samples. Significant correlations were observed between TLRs and complement fragments and between TLRs and some inflammatory mediators. Our findings pointed at TLR2 and TLR4 over-expression at early stages of ERM formation, suggesting the participation of the local immune response in the severity of disease. These activations at the early-stage of ERM formation suggest a potential persistence of innate immune response in the early phases of fibrocellular membrane formation.

Transcorneal Vitrectomy in Eyes with Regressed Retinoblastoma

Purpose: Current treatments for retinoblastoma facilitate globe salvage but can result in vitreoretinal disorders that may require surgery. There is controversy on surgical approaches in eyes with retinoblastoma. Here we describe a transcorneal vitrectomy approach that avoids the use of chemotherapy or cryotherapy. Methods: Retrospective chart review was performed on five consecutive patients with regressed retinoblastoma for >12 months (Group D/ct2b) at Children’s Hospital Los Angeles who had vitrectomy between November 2022 and December 2023. Results: Five patients underwent 8 vitrectomies for various indications including IOL fibrosis, vitreous hemorrhage, cataract, retinal detachment, and silicone oil removal. Mean age at first vitrectomy was 6.2 years (range: 2-9 years); mean time from last retinoblastoma treatment was 50.4 months (range: 20-82 months). Radially oriented corneal incisions were made with the 23-gauge or 25-gauge trocar system and the Versa HD LenZ (Oculus) was utilized with the RESIGHT (Zeiss) for top-down visualization. Neither chemotherapy nor cryotherapy were utilized. Wounds were sutured parallel to the limbus with 10-0 polyglactin 910 suture (Vicryl, Ethicon), and a final water rinse was performed to lyse any potential retinoblastoma cells. Surgical objectives were achieved, vision remained stable, and no retinoblastoma spread was noted with a mean follow-up of 7.6 months (range: 3-12 months). Conclusions: This vitrectomy technique for eyes with regressed retinoblastoma permits top-down viewing with the Versa HD LenZ. Radial placement of corneal wounds avoids suturing through the uveal tract, and a postsurgical water rinse lyses any retinoblastoma cells. This approach may obviate the need for chemotherapeutics or cryotherapy.

Interferons in vitreoretinal diseases; a review on their clinical application, and mechanism of action.

This review investigates the therapeutic benefits of interferons (IFNs) in vitreoretinal diseases, focusing on their regulatory roles in innate immunological reactions and angiogenesis. The study aims to categorize the clinical outcomes of IFN applications and proposes a molecular mechanism underlying their action. A systematic review was conducted using MEDLINE/PubMed, Web of Science, EMBASE, and Google Scholar databases to identify randomized clinical trials, case series, and case-control studies related to IFNs' impact on vitreoretinal diseases (1990-2022). The data synthesis involved an in-depth analysis of the anti-inflammatory and anti-angiogenesis effects of IFNs across various studies. Our findings indicate that IFNs exhibit efficacy in treating inflammation-associated vitreoretinal disorders. However, a lack of sufficient evidence exists regarding the suitability of IFNs in angiogenesis-associated vitreoretinal diseases like choroidal neovascularization and diabetic retinopathies. The synthesis of data suggests that IFNs may not be optimal for managing advanced stages of angiogenesis-associated disorders. While IFNs emerge as promising therapeutic candidates for inflammation-related vitreoretinal diseases, caution is warranted in their application for angiogenesis-associated disorders, especially in advanced stages. Further research is needed to elucidate the nuanced molecular pathways of IFN action, guiding their targeted use in specific vitreoretinal conditions.

CLINICALLY RELEVANT POSTERIOR VITREOUS DETACHMENT STAGING USING CIRCUMPAPILLARY AND MACULAR VOLUME OPTICAL COHERENCE TOMOGRAPHY.

This study was designed to investigate retinal nerve fiber layer circumpapillary optical coherence tomography to determine posterior vitreous detachment (PVD) status and to develop a clinically relevant PVD grading scale based on retinal nerve fiber layer circumpapillary optical coherence tomography to determine the incidence of PVD by age and association with vitreomacular traction disorders. Ophthalmic images and medical records of patients with retinal diseases were retrospectively analyzed by three masked graders using retinal nerve fiber layer circumpapillary optical coherence tomography and macular optical coherence tomography. Based on PVD status, eyes were categorized into five newly defined PVD stages. Among 2002 eyes, PVD stages were as follows: A) 25 (1.25%); B) 725 (36.21%); C-) 248 (12.39%); C+) 151 (7.54%); D) 851 (42.51%); X) 2 (0.1%). Posterior vitreous detachment was correlated with advanced age (P < 0.0001). Limited separation or partial separation between lamella within the posterior vitreous cortex (Stage B) was noted early (68% of eyes <18 years). Overall, 34% of eyes >70 years did not exhibit complete PVD. Of 75 eyes with tractional vitreoretinal disorders, 64 (85.3%) were Stage C-/C+, identifying Stage C as the high-risk "complication" stage. Imaging analyses using retinal nerve fiber layer circumpapillary optical coherence tomography and macular optical coherence tomography scans in conjunction allow rapid assessment of the PVD stage. These techniques can assist clinicians and surgeons in counseling patients and planning surgical approaches. Observations confirmed the progression of PVD through predictable stages and the progression of PVD with age.

Degradation of Photopic and Mesopic Contrast Sensitivity Function in High Myopes With Partial Posterior Vitreous Detachment.

The purpose of this study was to evaluate the effects of posterior vitreous detachment (PVD) on visual quality in patients with high myopia, as well as investigate the associated factors of photopic and mesopic contrast sensitivity function (CSF) in high myopia. Visual quality was comprehensively assessed in patients with high myopia. Visual acuity, contrast sensitivity (CS) at four spatial frequencies (3, 6, 12, and 18 cycles per degree [c.p.d.]) under photopic and mesopic conditions, as well as the modulation transfer function cutoff value (MTFcutoff), the objective scatter index (OSI), the Strehl ratio (SR), and internal aberrations, were measured in this cross-sectional study. This study included 94 eyes from 47 subjects with bilateral high myopia, including 23 eyes with complete PVD (cPVD), 21 eyes with partial PVD (pPVD), and 50 eyes without PVD (nPVD). There was no significant difference in visual quality between the cPVD group and the nPVD group. Whereas in eyes with pPVD, there was a degradation of overall photopic CSF (versus nPVD, P = 0.048), photopic CS at 3 c.p.d. (versus cPVD, P = 0.009 and versus nPVD, P = 0.032), photopic CS at 18 c.p.d. (versus nPVD, P = 0.033), overall mesopic CSF (versus nPVD, P = 0.033), and secondary astigmatism (versus cPVD, P = 0.044). Under photopic conditions, the factors affecting CSF were pPVD and SR, whereas the factors affecting mesopic CSF were pPVD, OSI, and ganglion cell-inner plexiform layer thickness. The pPVD impaired visual quality in patients with high myopia compared to nPVD or cPVD, and pPVD could be a factor explaining CSF at both photopic and mesopic illumination. Clinicians need to closely monitor patients with high myopia with pPVD due to the potential decline in visual quality and the development of vitreoretinal disorders.

Alterations in the Ocular Surface and Corneal Subbasal Nerve Plexus Following Various Retinal Surgical Procedures: A One-Year Confocal Microscopy Prospective Study.

To evaluate the effects of retinal surgery on the ocular surface and corneal subbasal nerve plexus (SNP). Ninety-eight patients undergoing 23-gauge pars plana vitrectomy for various vitreoretinal disorders were prospectively studied. We collected detailed operative and perioperative data, measuring dry eye syndrome (DED) severity and Ocular Surface Disease Index (OSDI) scores before surgery and at postoperative intervals. In vivo confocal microscopy (IVCM) quantified SNP and dendritic cell (DC) densities. Fifty-three patients were analyzed. Post-surgery, OSDI scores rose from a baseline of 5.5 ± 3.5 to 12.24 ± 6.5 at one month, later reducing to 7.8 ± 4.0 after a year. DED severity increased from 0.6 ± 0.6 initially to 1.6 ± 0.6 at three months, returning to near baseline (0.9 ± 0.6) one year after surgery. DC densities increased notably by the third (58.85 ± 75.6 cells/mm²) and ninth (59.95 ± 86 cells/mm²) postoperative months, especially in patients undergoing combined phacoemulsification, vitrectomy, and C3F8 gas tamponade. SNP parameters, particularly nerve fiber density and length, showed significant declines one month post-surgery, not recovering to baseline levels within a year. Fiber density dropped from 19.06 ± 8.3 fibers/mm² preoperatively to 4.68 ± 4.8 fibers/mm² at one month, partially recovering to 10.64 ± 8.2 fibers/mm² at twelve months. Fiber length decreased from 13.31 ± 3.2 mm/mm² to 6.86 ± 3.4 mm/mm² at one month, later improving to 9.81 ± 4.5 mm/mm² at twelve months, notably in patients with silicone oil (SiO2) tamponade. Retinal surgery, especially when combined with phacoemulsification and C3F8 or SiO2 tamponade, significantly affects ocular surface integrity and SNP density, with these changes lasting up to a year. Expanded studies with more patients and longer follow-up, using finer 25- and 27-gauge vitrectomy tools, are recommended to confirm and extend these findings.

Changes in Metamorphopsia in Patients Undergoing Treatment for Vitreoretinal Disorders.

To quantify and compare the severity of metamorphopsia in patients undergoing vitrectomy for vitreoretinal disorders. Data were collected evaluated from 319 patients with vitreoretinal disorders, including epiretinal membrane (ERM), macular hole (MH), cystoid macular edema with branch retinal vein occlusion (BRVO-CME), CME with central retinal vein occlusion (CRVO), diabetic macular edema (DME), macula-off rhegmatogenous retinal detachment (M-off RD), and macula-on RD (M-on RD). Metamorphopsia was recorded with the M-CHARTS preoperatively and at 3 and 6 months postoperatively. Preoperative and 6-month postoperative metamorphopsia scores were 0.69 ± 0.50 and 0.50 ± 0.52, respectively. Before surgery, 94% of patients presented with metamorphopsia (score ≥0.2). Preoperative metamorphopsia scores were significantly correlated with postoperative metamorphopsia scores (r = 0.378, p < 0.0001). Preoperative metamorphopsia score was significantly higher for ERM (0.89) than for DME (0.51). Vitrectomy significantly improved metamorphopsia in ERM and MH but not in the other disorders. In contrast, treatment improved visual acuity for all disorders except CRVO-CME and M-on RD. This quantitative study indicated that metamorphopsia is present in most patients undergoing surgery for vitreoretinal diseases and is most severe in ERM. In these patients, vitrectomy improved visual acuity but not metamorphopsia.

Combined cataract and vitreoretinal surgery

Combined cataract surgery and vitrectomy is a surgical technique used to address both cataract and vitreoretinal disorders. With the advances in surgical tools, simultaneous removal of cataract associated with vitreoretinal disorders is gaining popularity. This technique offers several advantages over separate surgeries, including reduced surgical time and anaesthesia exposure, as well as quicker visual rehabilitation. However, the optimal timing and approach for combined cataract surgery and vitrectomy remain controversial.Indications for combined cataract surgery and vitrectomy include various vitreoretinal conditions, such as retinal detachment, diabetic retinopathy, macular holes, and epiretinal membranes. The timing of surgery depends on the severity of the cataract and the vitreoretinal pathology, as well as the surgeon's preference. The most common surgical techniques include phacoemulsification with posterior chamber intraocular lens implantation, followed by pars plana vitrectomy. The filling of the vitreous cavity is possible with several types of tamponades, such as different gases, but in extreme cases even with silicone oil. After gas tamponade, proper positioning of the patient is of great importance.Complications associated with combined cataract surgery and vitrectomy include posterior capsule rupture, intraocular lens dislocation, postoperative inflammation, and intraocular pressure elevation. However, the overall complication rate is low, and the visual outcomes are generally favourable.In conclusion, combined cataract surgery and vitrectomy is a useful technique for managing various vitreoretinal conditions. Proper patient selection, careful surgical planning, and close postoperative monitoring are critical for achieving optimal outcomes.

Wound healing and postoperative management in paediatric patients following 27-Gauge Transconjunctival Sutureless Vitrectomy for vitreoretinal conditions.

The utilization of 27-G TSV, or 27-Gauge Transconjunctival Sutureless Vitrectomy, poses distinct difficulties in the context of paediatric patients, particularly those younger than 14 years old, on account of the dearth of exhaustive documentation concerning the efficacy and results of these operations. Therefore, this retrospective study was to evaluate the safety and efficacy of 27-G TSV in paediatric patients, with emphasis on management of intraoperative and postoperative complications and postoperative wound healing. A total of 54 eyes of 52 paediatric patients who underwent 27-G TSV at Sichuan Provincial People's Hospital were included in the study. The average duration of follow-up was 9.32 ± 3.35 months. The complication with the highest incidence rate was Rhegmatogenous Retinal Detachment (RRD), which was detected in 27.8% cases. Familial Exudative Vitreoretinopathy (FEVR) and Persistent Fetal Vasculature (PFV) each accounted for 16.7% of the cases. Retinopathy of Prematurity (ROP) and Vitreous Haemorrhage (VH) constituted 11.1% and 14.8%, respectively, of the reported cases. Lens injury (1.9%), cannula slippage (7.4%) and wound leakage (5.6%) were intraoperative complications. Iatrogenic retinal detachment occurred at 3.7%. Hypotony (10.8% of patients), vitreous haemorrhage (9.3%), cataract formation (9.3%), ocular hypertension (8.1%) and retinal detachment (5.6%) were postoperative complications. Effective management strategies were executed, such as performing in situ trocar puncture to address cannula slippage and promptly suturing to address wound leakage. 27-G TSV exhibited promise as the therapeutic alternative for range of vitreoretinal disorders in paediatric patients, accompanied by complications that were controllable during and after the procedure. Strict preoperative planning and precise surgical technique are indispensable in order to maximize patient outcomes and guarantee effective wound healing and recovery within this particular demographic.

Технология микрохирургической реконструкции фовеа при макулярных разрывах

Macular rupture is among major vitreoretinal disorders resulting in significant visual function decline. In recent years, the use of platelet-rich autoplasma in the macular rupture surgery is considered to be promising. However, despite high rate of macular rupture closure (78–96%), the development of new technology for foveal microarchitectonics restoration and visual function improvement currently remains a pressing issue. The study was aimed to develop a new foveal reconstruction technique for macular rupture involving the use of autologous conditioned plasma. The reported study involved 9 patients (10 eyes) with idiopathic macular hole, who underwent standard three-port 27G vitrectomy involving the use of autologous conditioned plasma in accordance with the technique developed. The proposed technique makes it possible to achieve good clinical and functional surgical treatment outcome and ensures optimal and more manageable reconstruction of foveal microarchitectonics.

TEMPORARY KERATOPROSTHESIS COMBINED WITH VITRECTOMY FOR SEVERE GLOBE INJURY.

To describe a case of a 44-year-old man with ocular trauma after a mine explosion. From the moment of the injury, the patient reported significant visual impairment (no perception of light in the right eye and a perception of light without localization in the left eye). The patient was diagnosed with a double-sided penetrating corneal scleral wound and traumatic cataract, retinal detachment, and intraocular foreign bodies after a battlefield mine explosion. The three-stage procedure, consisting of using soft contact lens as temporary keratoprosthesis, vitrectomy, and penetrating keratoplasty, was performed in the damaged eye. A soft contact lens allowed for excellent visualization of the posterior segment during vitrectomy. At the 1-month follow-up, the eye that was operated on could sense light. The corneal transplant remained translucent, and the retina was attached. The described method, when performed by an experienced surgeon, may aid in simultaneously treating coexisting corneal opacification and vitreoretinal disorders.

Macrophage-Myofibroblast Transition Contributes to Myofibroblast Formation in Proliferative Vitreoretinal Disorders.

Inflammation and fibrosis are key features of proliferative vitreoretinal disorders. We aimed to define the macrophage phenotype and investigate the role of macrophage-myofibroblast transition (MMT) in the contribution to myofibroblast populations present in epiretinal membranes. Vitreous samples from proliferative diabetic retinopathy (PDR), proliferative vitreoretinopathy (PVR) and nondiabetic control patients, epiretinal fibrovascular membranes from PDR patients and fibrocellular membranes from PVR patients, human retinal Müller glial cells and human retinal microvascular endothelial cells (HRMECs) were studied by ELISA, immunohistochemistry and flow cytometry analysis. Myofibroblasts expressing α-SMA, fibroblast activation protein-α (FAP-α) and fibroblast-specific protein-1 (FSP-1) were present in all membranes. The majority of CD68+ monocytes/macrophages co-expressed the M2 macrophage marker CD206. In epiretinal membranes, cells undergoing MMT were identified by co-expression of the macrophage marker CD68 and myofibroblast markers α-SMA and FSP-1. Further analysis revealed that CD206+ M2 macrophages co-expressed α-SMA, FSP-1, FAP-α and ß-catenin. Soluble (s) CD206 and sFAP-α levels were significantly higher in vitreous samples from PDR and PVR patients than in nondiabetic control patients. The proinflammatory cytokine TNF-α and the hypoxia mimetic agent cobalt chloride induced upregulation of sFAP-α in culture media of Müller cells but not of HRMECs. The NF-ĸß inhibitor BAY11-7085 significantly attenuated TNF-α-induced upregulation of sFAP-α in Müller cells. Our findings suggest that the process of MMT might contribute to myofibroblast formation in epiretinal membranes, and this transition involved macrophages with a predominant M2 phenotype. In addition, sFAP-α as a vitreous biomarker may be derived from M2 macrophages transitioned to myofibroblasts and from Müller cells.

Choroidal vascularity index changes in different treatments for vitreomacular traction

IntroductionThe aim of this study was to examine if choroidal vascularity index (CVI) is different in eyes with unilateral vitreomacular traction (VMT) from their healthy fellow eyes; and whether different treatments affect the CVI. MethodsThe baseline and 8-week post treatment CVIs of 56 unilateral VMT patients that underwent spontaneous resolution (n = 30), vitreoretinal surgery (n = 16) or pneumatic vitreolysis (n = 10) were compared with fellow eyes using paired samples t-test. Partial correlation analyses correcting age and gender was used for calculations between treatment groups. P values < 0.05 were considered statistically significant. ResultsThe mean baseline CVI for VMT and control eyes had no statistically significant difference (p = 0.81, r= -0.38). The post traction release follow-up CVI of VMT eyes and contralateral eyes had no significant difference (p = 0.12, r = 0.49). In spontaneous resolution group, vitreoretinal surgery group and pneumatic vitreolysis group the baseline and follow up CVIs of VMT eyes were statistically similar (p = 0.72, p = 0.32 and p = 0.79 respectively).Spontaneous detachment patients’ CVIs showed a 0.57±5.81% increase, vitreoretinal surgery group had a reduction of 1.098±4.76%, and the pneumatic vitreolysis patients showed a CVI reduction of 0.307±4.24%. However, none of these changes was found to be statistically significant when compared between the groups (p = 0.21, r = 0.02). DiscussionPrevious studies have argued that vitreomacular traction might have a role on the choroidal changes seen in the vitreoretinal interface disorders. This study has shown that VMT alone does not cause any significant changes in choroidal vascular index pre or post traction release.

A Prospective Randomized Study Comparing 27-Gauge Vitrectomy to 23-Gauge Vitrectomy for Epiretinal Membranes and Full-Thickness Macular Holes.

To compare the surgical and clinical outcomes of 27-gauge vitrectomy and 23-gauge vitrectomy. We conducted a single-center, prospective, randomized study. Fifty-three patients affected by vitreoretinal interface disorders (epiretinal membranes and macular holes) were randomly scheduled to undergo 27-gauge (28 patients) or 23-gauge (25 patients) pars plana vitrectomy. The presence of any potential factor of increased baseline inflammation or eye anatomy influencing the surgery was criteria for exclusion. The time of surgery, postoperative intraocular pressure (IOP), state of sclerotomy wounds, rate of complications, postoperative pain, and indicators of inflammation were studied. We also introduced a new parameter to compare intraocular inflammation after surgery, given by the change in the number of intraretinal hyperreflective foci (HRF). The 27-gauge vitrectomy was 1.28 min longer than 23-gauge vitrectomy (P < 0.05). The day after surgery, the mean IOP value was significantly higher in the 27-gauge group (16.12 mmHg versus 13.04 mmHg in the 23-gauge group,P < 0.05), but this difference disappeared in successive follow-ups and the sclerotomy wounds closed after 2 weeks in the both groups. The rate of postoperative hypotony did not significantly differ in the two groups (10.71% in the 27-gauge group and 8% in the 23-gauge group the day after the surgery,P = 0.94). Less postoperative eye redness was seen in 27-gauge eyes (value 1 on the scale) compared to 23-gauge (value 2 on the scale) (P < 0.05), but there was no significant difference in intraocular inflammation (cells, Tyndall, and number of HRF,P > 0.05 for all). The 27-gauge vitrectomy may have better outcomes in terms of IOP maintenance and cause less redness after the surgery but with a slightly prolonged surgery time and no other differences under other parameters (inflammation, rate of complications, postoperative pain, visual gain, and closure of the sclerotomy wounds).

Dry eye parameters measured with an ocular surface analyzer in eyes after vitrectomy for vitreomacular interface disorders.

Dry eye disease (DED) might be caused by multiple ocular surgical interventions. The aim of the study was to estimate the extent of DED in patients undergoing core vitrectomy for vitreoretinal interface disorders. In this prospective observational study, we included patients with 12 months of follow-up after vitrectomy. The following data were collected as controls: age, sex, best-corrected visual acuity before and after surgery, and phakic status. In OSA (ocular surface analysis), the following parameters were evaluated: NIBUT (non-invasive tear break-up time), sltDear (thickness of the lipid layer), Meibomian gland (MGD) loss, and the height of tear meniscus. Shapiro-Wilk test, Wilcoxon rank-sum test, and Mann-Whitney U tests were used for statistical analysis. We evaluated 48 eyes of 24 patients (10 men, 14 women; 64.63 ± 14.10 years) 1 year after vitrectomy. From the analyzed ocular surface parameters, NIBUT was significantly lower in operated versus non-operated eyes (P = 0.048). The higher the level of difference in MGD loss between both eyes, the higher the level of difference in NIBUT between both eyes (rs = 0.47, P = 0.032). NIBUT levels were still decreased 12 months after vitrectomy. Patients with more pronounced MGD loss or decreased NIBUT levels in the fellow eye were more likely to experience such disorders. The tear meniscus height was lower in patients undergoing surgery for retinal detachment than in those with vitreoretinal disorders. This might allow the suggestion to include artificial tears in pre- and post-operative care in vitrectomized eyes.

Vision-related quality of life after surgery for vitreoretinal disorders in a Mexican population: an observational study

Visual-related quality of life in retinal diseases has not been explored in the Mexican population, so the study aims to identify it in patients undergoing surgery due to advanced diabetic retinopathy, rhegmatogenous retinal detachment, and other causes of vitrectomy; the Visual Function Quality-25 questionnaire was applied to 76 patients, pre-and postoperative. It was divided into 10 domains and interpreted according to the National Eye Institute scores, where the highest value was the best visual function. Student's t-test for related samples and Wilcoxon’s t-test were used to compare each domain between measurements, and Pearson’s R test to correlate the total score of age and quality of life; a p value < 0.05 was considered significant. Diabetic retinopathy patients showed an improvement 1 and 3 months after surgery in all domains; in rhegmatogenous retinal detachment, there was an improvement observed up to 3 months, while a decrease in ocular pain was observed in other causes of vitrectomy. Differences found in all the quality-of-life scores were not statistical, but clinically significant. The study shows that visual-related quality of life domains improves after vitrectomy; the inclusion of this analysis might be considered relevant within the parameters of surgical success of the most prevalent vitreoretinal diseases.

OCT-guided Robotic Subretinal Needle Injections: A Deep Learning-Based Registration Approach.

Subretinal injection (SI) is an ophthalmic surgical procedure that allows for the direct injection of therapeutic substances into the subretinal space to treat vitreoretinal disorders. Although this treatment has grown in popularity, various factors contribute to its difficulty. These include the retina's fragile, nonregenerative tissue, as well as hand tremor and poor visual depth perception. In this context, the usage of robotic devices may reduce hand tremors and facilitate gradual and controlled SI. For the robot to successfully move to the target area, it needs to understand the spatial relationship between the attached needle and the tissue. The development of optical coherence tomography (OCT) imaging has resulted in a substantial advancement in visualizing retinal structures at micron resolution. This paper introduces a novel foundation for an OCT-guided robotic steering framework that enables a surgeon to plan and select targets within the OCT volume. At the same time, the robot automatically executes the trajectories necessary to achieve the selected targets. Our contribution consists of a novel combination of existing methods, creating an intraoperative OCT-Robot registration pipeline. We combined straightforward affine transformation computations with robot kinematics and a deep neural network-determined tool-tip location in OCT. We evaluate our framework's capability in a cadaveric pig eye open-sky procedure and using an aluminum target board. Targeting the subretinal space of the pig eye produced encouraging results with a mean Euclidean error of 23.8μm.

Pars plana vitrectomy for vitreoretinal interface disorders coincident with intermediate stage age-related macular degeneration.

Currently around 67 million people in Europe are affected by some form of age-related macular degeneration (AMD). As most known types of vitreoretinal (VR) interface disorders can coexist with AMD and as we can favourably affect the former with vitreoretinal surgery, our goal was to evaluate the results of vitreoretinal interface disorder surgery with macular peeling in relation to coincident intermediate stage AMD. This was a retrospective evaluation of eyes operated with 25-gauge pars plana vitrectomy (PPV). The monitored parameters were anatomical and functional findings and, safety of the procedure. The surface of the macula was stained with trypan blue and treated (peeling) with a disposable microforceps. 10% perfluoropropane, or the air tamponade was used. Distance visual acuity was examined on the ETDRS chart, the macular finding was monitored by OCT and photodocumented. The post-operative face-down position was 3-5 days. The follow-up period was 6 months. 17 eyes (14 patients, woman 86%) mean age 74 years. The primary indications for the procedure were: idiopathic macular hole (IMD) 59%, epiretinal membrane 29% and vitreomacular traction syndrome 12%. Ophthalmoscopic and OCT findings of intermediate dry form of AMD (100%), in 24% was drusoid ablation of the pigment leaf. In all cases of IMD, primary closure occurred. Input visual acuity 0.1-0.6 improved to 0.2-0.9 at the end of the follow-up period (P<0.05). No complications during surgery or progression of AMD in the follow-up period were observed. PPV for vitreoretinal interface disorders have similar anatomical results, whether the outer part of the retina is disrupted by intermediate AMD or not. Functional results are affected by possible disruption of the RPE or the outer layers of the neuroretina by AMD. The PPV procedure has a standard security profile. It is safe and does not affect the progression of AMD in the short term.

Anatomical and functional results of vitrectomy and gas tamponade in macular hole treatment

AbstractBackground: Idiopathic macular holes (IMH) of large sizes are still challenging for vitreoretinal surgeons. Predict factors of the treatment effectiveness are little‐known.Purpose: To evaluate the effectiveness of large idiopathic macular holes surgery with 18% perfluoropropane (C3F8) gas tamponade.Methods: The retrospective study, which includes 68 eyes of 68 patients diagnosed with IMH stage 3 or stage 4 (Gass classification) between January 2015 and January 2020. Among them, there were 16 men (23.5%) and 52 women (76.5%). The mean age of patients was 66.7 ± 4.3. Morphologic parameters of the macular hole (base diameter, minimum diameter) were measured and then hole form factor (HFF) was calculated. All eyes underwent 25 gauge pars plana vitrectomy, internal limiting membrane peeling, 18% C3F8 gas tamponade and postoperative face‐down positioning for two weeks. The minimum follow‐up period was 3 months and the mean follow‐up period was 19.6 ± 11.4 months. The main outcome measures were IMH closure confirmed by spectral domain optical coherence tomography at 1 month postoperatively and visual acuity at 3 months postoperatively.Results: No intra‐ and postoperative complications were observed. The IMH were closed in 61 out of 68 eyes at one month after surgery. The anatomic closure rate was 89.7%. The mean base diameter of IMH was 1022.82 ± 292.36 μm (range: 682–2019 μm). The mean minimum diameter of IMH was 471.71 ± 138.73 (range: 258–766 μm). The mean preoperative BCDVA was 0.72 ± 0.29 logMAR and mean postoperative BCDVA at 3 months after surgery was 0.5 ± 0.33 logMAR (p = 0.063, t‐test). In 47 patients (69.1%) BCDVA improved after surgery. Mean gain in visual acuity at 3 months after operation was 0.20 ± 0.27 (ΔBCDVA, logMAR). Visual acuity worsened or remained unchanged after surgery in 21 patients (30.9%) due to postoperative vitreoretinal interface disorders (foveal thinning, retinal pigment epithelium defects, and foveal cysts). The mean HFF value was 0.77 ± 0.09. There was a statistically significant moderate positive correlation between HFF and postoperative BCDVA (r = 0.56, p = 0.03, Spearman's Rho).Conclusion: Macular hole surgery with 18% C3F8 tamponade is effective technique and is associated with high rates of IMH closure and postoperative BCVA improvement. HFF was significantly correlated with postoperative visual outcomes in cases of large IMH.