[Ischemia and laser photocoagulation in retinal vein occlusion]. / Ischämie und Lasertherapie bei retinalen venösen Verschlüssen.

BACKGROUND: Retinal vein occlusions (RVO) are associated with retinal ischemia to a highly variable extent. An ischemic retina may lead to the development of neovascularization and further to secondary complications such as neovascular glaucoma, vitreous hemorrhage or tractional retinal detachment. Numerous factors such as vascular endothelial growth factor (VEGF) and other cytokines are produced in the ischemic area, which cause macular edema. Before the introduction of intravitreal drug injections (IVI), retinal laser photocoagulation was the leading form of treatment. Macular laser photocoagulation was applied in the form of focal laser or grid laser in patients with branch retinal vein occlusion (BRVO) to treat macular edema. In patients with ischemic RVO, panretinal laser photocoagulation (PRP) was recommended for treatment of secondary neovascular complications. The value of laser treatment in the management of patients with RVO changed after the introduction of IVI treatment. AIM: This article presents a review of the current study results and the recommendations for performing laser photocoagulation of the central and peripheral retina in patients with RVO. CONCLUSION: Conventional focal or grid laser photocoagulation has been replaced by IVI treatment in the management of macular edema secondary to BRVO; however, macular laser treatment can still be considered in patients with BRVO if the macular edema persists despite the use of available IVI drugs. The use of central laser photocoagulation in these cases is based on the findings of fluorescein angiography. Disseminated panretinal laser photocoagulation is still indicated in RVO patients who have large areas of nonperfusion, have developed neovascularization and/or late complications. Targeted laser photocoagulation of the peripheral areas of nonperfusion has recently been recommended by several authors and is expected to improve not only the visual outcome of IVI treatment, but more importantly to also reduce the duration of treatment and the number of re-injections needed. Clear evidence for targeted laser treatment is not yet available and is a focus of currently ongoing prospective randomized studies.

Influence of the Size of the Foveal Avascular Zone on Functional and Morphological Parameters in Patients with Early-Stage Diabetic Retinopathy.

Purpose: To correlate functional and morphological parameters with foveal avascular zone's (FAZ) size in diabetic patients with mild to moderate stage nonproliferative diabetic retinopathy. Methods: Monocentric and prospective study of a consecutive case series of diabetic patients. Medical history, best corrected visual acuity (BCVA), best corrected high/low contrast visual acuity (BChcVA/BClcVA), mean sensitivity (MS) and mean defect (MD) in central visual field testing, and FAZ size in fluorescein-angiography (FAG) were recorded. Macular thickness (central point thickness CPT, central subfield thickness CST) and volume measurements (central subfield volume CSV, total macular volume) were taken from SD-OCT (6x6mm ETDRS-grid). Groups were categorised as presenting FAZ sizes smaller (G1) or larger (G2) than 0.35mm2. Smallest (Q1) and largest quartiles (Q3) were also compared. Results: Thirty-six of 40 patients were included. MS differed significantly between G1 (n = 6) and G2 (n = 30), and BChcVA/BClcVA as well as TMV correlated significantly with FAZ size in correlation analysis. Mean HbA1c tended to be lower in G1 than G2. Patients in G1 were slightly older than in G2. Treatment period with insulin was shorter in G1/Q1 than in G2/Q3. CPT and TMV were lower in G1/Q1 than in G2/Q3. Our analysis of the FAZ in terms of patient age, HbA1c, disease duration and insulin therapy duration revealed no significance. That lack of significance also applies to BCVA, MS, MD, CPT, CST and CSV. Conclusion: As significantly associated, contrast sensitivity, central visual field parameters and potentially retinal thickness or volume seem to be suitable to detect early macular ischaemia. However, we failed to establish any correlation between FAZ and BCVA.

Risk Factors for Severe Bleeding Complications in Vitreoretinal Surgery and the Role of Antiplatelet or Anticoagulant Agents.

PURPOSE: To evaluate the influences and risk factors for severe bleeding complications during vitreoretinal surgery and to investigate the role of antiplatelet and anticoagulant agents. DESIGN: Prospective trial. PARTICIPANTS: Patients undergoing vitreoretinal surgery. METHODS: The procedures included were pars plana vitrectomy and scleral buckling. We developed a uniform classification to grade the bleeding severity. Bleeding was graded on an ordinal scale ranging from 0 to 5. Immediately after surgery and 1 day later, the incidence and the severity of bleeding events was documented on a standardized form. A grade of 3 or more was defined as severe bleeding. Furthermore, the influence of known systemic disorders before surgery, the type of anesthesia, type of surgical procedure, intraoperative blood pressure, and the use or change of antiplatelet or anticoagulant agents on intraoperative bleeding was analyzed. MAIN OUTCOME MEASURES: Incidence and risk factors for severe intraoperative bleeding events. RESULTS: Data from 374 eyes undergoing vitreoretinal procedures were included in our study (mean age, 67.6 ± 12.9 years). A severe intraoperative bleeding event was observed in 15 eyes (4%). We found that concomitant diseases such as diabetes mellitus and carotid artery stenosis, the presence of diabetic retinopathy, younger age, and scleral buckling combined with a transscleral puncture were associated significantly with severe bleeding events. By contrast, use of antiplatelet or anticoagulant agents, or both, had no significant influence on severe intraoperative bleeding events. CONCLUSIONS: Although external manipulations during buckling surgery (e.g., drainage of subretinal fluid) and concomitant diseases such as diabetes mellitus and carotid artery stenosis influences the risk of severe intraoperative bleeding events, we did not detect an increased risk related to coexisting antiplatelet or anticoagulant medication use, or both.

Reliability of Subjective Assessment of Spectral-Domain OCT Pathologic Features by Multiple Raters in Retinal Vein Occlusion.

Purpose: To examine the interrater and intrarater reliability of qualitatively and quantitatively assessed disorganization of retinal inner layers (DRIL) and disorganization of retinal outer layers (DROL) by multiple raters. Subjectively assessing these surrogate biomarkers can be challenging in daily routine, despite the high resolution of spectral-domain (SD) OCT scans. Design: Retrospective trial. Participants: Three hundred six pooled SD OCT scans of 34 patients treated for macular edema caused by retinal vein occlusion (RVO) between January 2016 and December 2017. Methods: SD OCT scans were assessed by 6 raters regarding presence of cystoid macular edema, subretinal fluid (SRF), vitreoretinal traction, and epiretinal membrane and extent of DRIL and DROL. Main Outcome Measures: Interrater and intrarater reliability were calculated applying κ statistics for qualitative assessment regarding each pathologic feature's presence in all evaluated OCT scans, and for quantified horizontal DRIL and DROL extent within each OCT cross-section. Results: Cystoid macular edema and SRF assessments revealed excellent inter- and intrarater reliability with almost perfect strength of agreement, whereas subjective DRIL and DROL evaluations yielded low κ statistics with slight to moderate strength of agreement. Furthermore, the presence of SRF remarkably compromised the reliability of DROL detection. Conclusions: Our data highlight the limited subjective assessibility of DRIL and DROL, underscoring the need for automated image analysis to improve the reliability of OCT biomarkers for clinical studies and daily practice.

Case report of a secondary macular hole closure after intravitreal bevacizumab therapy in a patient with retinal pigment epithelial detachment.

We describe a case of macular hole (MH) closure after intravitreal bevacizumab therapy for an underlying pigment epithelial detachment (PED) due to exudative age-related macular degeneration (AMD). The 73-year-old Caucasian female presented with reduced visual acuity (20/80) of the left eye and metamorphopsia for approximately 6 months. Spectral domain optical coherence tomography revealed a subfoveal PED due to AMD with an associated MH. To treat the exudative component of the pathology, we started intravitreal bevacizumab therapy, consecutively leading to reduction of the height of PED and allowing closure of the MH. Detachment recurred during further follow-up, but the MH remained closed. MHs and exudative AMD are common diseases, which rarely occur simultaneously. To the best of our knowledge (search via PubMed for "MH," "PED," "age-related macular degeneration"), no other case with the persistent closure of an MH associated with PED during intravitreal antivascular endothelial growth factor therapy and despite recurrent PED has been published to date.