WIDE-FIELD SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY OF DIABETIC TRACTIONAL RETINAL DETACHMENTS BEFORE AND AFTER SURGICAL REPAIR

Tractional Retinoschisis in Proliferative Diabetic Retinopathy Imaged With Swept-Source Optical Coherence Tomography Angiography

Tractional retinoschisis (TRS) secondary to proliferative diabetic retinopathy (PDR) may be differentiated from tractional retinal detachment (TRD) by its characteristically nonprogressive course. The purpose of the current study was to describe the use of swept-source optical coherence tomography angiography (SS-OCTA) in the diagnosis and monitoring of TRS secondary to PDR. Retrospective, consecutive case series of patients with TRS secondary to PDR are featured. Clinical notes, fundus photography, and SS-OCTA images are reviewed. The study comprised three eyes of three patients with PDR and TRS. Visual acuity and anatomic features on SS-OCTA were stable in all patients at one year or more of follow-up. Tractional retinoschisis secondary to PDR is typically nonprogressive and may be observed without surgery. SS-OCTA serves as a noninvasive and effective imaging tool to distinguish TRS from TRD and to demonstrate anatomic stability over time. [Ophthalmic Surg Lasers Imaging Retina 2024;55:244-248.].

Elucidating postoperative dynamics in tractional retinal detachment: a systematic review and meta-analysis of structural and functional outcomes following diabetic vitrectomy, including an analysis of postoperative complications

This meta-analysis aims to evaluate the efficacy and safety of diabetic vitrectomy for treating tractional retinal detachment (TRD) by assessing visual acuity improvements, retinal reattachment success rates, and the frequency of postoperative complications. A comprehensive literature search identified 1,211 studies, 30 of which met the inclusion criteria and were analyzed. The meta-analyses were conducted via random effects models to account for heterogeneity. The primary outcomes were visual acuity improvement and retinal reattachment success, whereas postoperative complications were analyzed as secondary outcomes. Funnel plots, trim-and-fill methods, and Egger's regression tests were employed to assess and adjust for publication bias. The meta-analysis included data from 1,844 eyes across 30 studies. The pooled mean difference (MD) in visual acuity following diabetic vitrectomy was 0.80 logMAR (95% CI: 0.58-1.01, p < 0.0001), with significant heterogeneity (I² = 95%). The trim-and-fill method adjusted the MD to 1.15 (95% CI: 0.85-1.45), indicating potential publication bias. The pooled proportion of retinal reattachment success was 94.63% (95% CI: 90.88-96.89%), with substantial heterogeneity (I² = 82.2%). Egger's regression test confirmed publication bias in the retinal reattachment data (t = 6.07, df = 25, p < 0.0001). The most common postoperative complications were vitreous hemorrhage (8.2%, 0-41%), elevated intraocular pressure (7.3%, 0-25%), and cataract formation (10.3%, 0-43%). Diabetic vitrectomy significantly improves visual acuity and achieves high retinal reattachment success rates in patients with TRD despite considerable heterogeneity across studies. However, a critical limitation of the current literature is the lack of comprehensive reporting of essential markers of perfusion, such as the choroidal vascularity index and choriocapillaris flow area, which are crucial for a thorough understanding of the impact of vitrectomy on ocular perfusion and its correlation with structural and functional outcomes. These findings also highlight the need for vigilant postoperative management to mitigate common complications. Adjustments for publication bias via the trim-and-fill method suggest that the initial estimates of efficacy may be optimistic, but the overall benefits of the procedure remain substantial. Further research is warranted to standardize surgical techniques, include detailed perfusion outcomes, and enhance the reliability of future meta-analyses. Trial registration: Retrospectively registered.

Optical coherence tomography angiography in diabetic retinopathy: A major review

Diabetic retinopathy (DR) is characterized by retinal vasculopathy and is a leading cause of visual impairment. Optical coherence tomography angiography (OCTA) is an innovative imaging technology that can detect various pathologies and quantifiable changes in retinal microvasculature. We briefly describe its functional principles and advantages over fluorescein angiography and perform a comprehensive review on its clinical applications in the screening or management of people with prediabetes, diabetes without clinical retinopathy (NDR), nonproliferative DR (NPDR), proliferative DR (PDR), and diabetic macular edema (DME). OCTA reveals early microvascular alterations in prediabetic and NDR eyes, which may coexist with sub-clinical neuroretinal dysfunction. Its applications in NPDR include measuring ischemia, detecting retinal neovascularization, and timing of early treatment through predicting the risk of retinopathy worsening or development of DME. In PDR, OCTA helps characterize the flow within neovascular complexes and evaluate their progression or regression in response to treatment. In eyes with DME, OCTA perfusion parameters may be of predictive value regarding the visual and anatomical gains associated with treatment. We further discussed the limitations of OCTA and the benefits of its incorporation into an updated DR severity scale.

Advances in swept-source optical coherence tomography and optical coherence tomography angiography

Background

The fast development of swept-source optical coherence tomography (SS-OCT) and swept-source optical coherence tomography angiography (SS-OCTA) enables both anterior and posterior imaging of the eye. These techniques have evolved from a research tool to an essential clinical imaging modality.

Main text

The longer wavelength and faster speed of SS-OCT and SS-OCTA facilitate better visualization of structure and vasculature below pigmented tissue with a larger field of view of the posterior segment and 360-degree visualization of the anterior segment. In the past 10 years, algorithms dealing with OCT and OCTA data also vastly improved the image quality and enabled the automated quantification of OCT- and OCTA-derived metrics. This technology has enriched our current understanding of healthy and diseased eyes. Even though the high cost of the systems currently limited the widespread use of SS-OCT and SS-OCTA at the first beginning, the gap between research and clinic practice got obviously shortened in the past few years.

Conclusions

SS-OCT and SS-OCTA will continue to evolve rapidly, contributing to a paradigm shift toward more widespread adoption of new imaging technology in clinical practice.

Advances in application of swept-source optical coherence tomography angiography in diagnosis and treatment of diabetic retinopathy

Diabetic retinopathy (DR) is the most common microvascular complication of diabetes and one of the leading causes of global blinding. More attention should be paid to the diagnosis, treatment and prognosis of DR. Swept-source optical coherence tomography angiography (SS-OCTA) is a novel imaging technique presented in recent years. It can accurately present the various levels of the retina, choriocapillaris, macula, and the optic papillary microcirculation, which is new to the diagnosis and prognosis of DR. However, SS-OCTA is limited by poor fixation or severe media clouding and is susceptible to motion artefacts and segmentation errors. Future limitations need to be addressed and large prospective trials conducted to refine the relevance of SS-OCTA to DR. The present study reviews the advances in clinical application of SS-OCTA in diagnosis, treatment and prognosis of DR.

An update on the management of diabetic tractional retinal detachment

Background: Tractional retinal detachment (TRD) occurs when contractile forces in the vitreous and neovascular tissue lead to the detachment of the neurosensory retina. The pre-operative use of antivascular endothelial growth factor (anti-VEGF) and advances in microsurgical instrumentation, such as a small gauge vitrectomy (SGV), have improved surgical outcomes.Aim: The purpose of this review is to highlight recent trends in the management of diabetic TRD, supporting earlier surgical intervention and the expanded surgical indications.Methods: PubMed was searched for the following terms: ‘diabetes’ OR ‘diabetic retinopathy’ AND ‘TRD’ AND ‘pars plana vitrectomy (PPV)’ AND ‘anti-VEGF’ AND ‘endophotocoagulation’. Reference lists were reviewed for additional articles. The review was focused on all articles later than 2010 for recent updates on the ever-changing management of this disease entity. No case reports were included in this review article.Results: Management of TRD continues to remain challenging, despite the recent advancements in techniques and instrumentation. Each case needs to be individualised, with careful pre-operative planning, understanding of patient expectations and counselling, coupled with meticulous surgical skills and diligent postoperative management.Conclusion: Management of TRD continues to remain challenging despite recent advances in techniques and instrumentation. Vitrectomy for TRD can improve vision-related quality of life, and the continued evolution and improvement in surgical techniques and adjunctive pharmacotherapy will most likely continue to improve postoperative outcomes.Contribution: The paper presents an overview of current management of tractional retinal detachment in patients with advanced proliferative diabetic retinopathy. 

LONGITUDINAL ANALYSIS OF DIABETIC CHOROIDOPATHY IN PROLIFERATIVE DIABETIC RETINOPATHY TREATED WITH PANRETINAL PHOTOCOAGULATION USING WIDEFIELD SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY

PURPOSE

Widefield swept-source optical coherence tomography (OCT) imaging was used to characterize choroidal thickness and vascularity at baseline in proliferative diabetic retinopathy (PDR) and longitudinally after panretinal photocoagulation (PRP).

METHODS

Patients with treatment-naive PDR were imaged at baseline and at 1 week, 1 month, and 3 months after PRP. Previously validated algorithms were used to calculate the mean choroidal thickness (MCT) and choroidal vascularity index (CVI) in 5 regions of 12 mm × 12 mm scans.

RESULTS

Fourteen PDR eyes were included. Baseline MCT in PDR eyes did not differ significantly from normal eyes, but CVI measurements in PDR eyes were lower in all regions (P < 0.001-0.008). After PRP, MCT measurements in PDR eyes were significantly lower at 1 month and 3 months in all regions (P < 0.001-0.005) except the fovea (P = 0.074). However, CVI measurements did not change over time in any region after PRP.

CONCLUSION

The choroid in PDR eyes has a smaller CVI than that in normal eyes. After PRP, the choroidal thickness decreases outside the fovea, but the CVI remains constant, which suggests that a relative decrease in choroidal vascularity persists. These widefield swept-source OCT results are consistent with choroidal alterations found in histopathological reports of diabetic choroidopathy.

WF SS-OCTA for detecting diabetic retinopathy and evaluating the effect of photocoagulation on posterior vitreous detachment

PURPOSE

This study aimed to assess the clinical usefulness of widefield swept source optical coherence tomography angiography (WF SS-OCTA) for detecting microvasculature lesions in diabetic retinopathy (DR) by comparing it with ultra-widefield fluorescein angiography (UWFFA) and to investigate the effect of panretinal photocoagulation (PRP) on posterior vitreous detachment (PVD) status.

METHODS

Patients with severe non-proliferative DR (NPDR) or proliferative DR (PDR) who were initially treated with PRP were enrolled. They underwent WF SS-OCTA with a 12×12-mm scan pattern of five visual fixations at baseline and at least a 3-month follow-up after PRP treatment. Patients with no contraindications underwent imaging with UWFFA within a week. Images were evaluated using two methods for the areas of the visible field of view (FOV), non-perfusion area (NPA), presence of neovascularization of the disc (NVD), neovascularization elsewhere (NVE), and PVD status.

RESULTS

In total, 44 eyes of 28 patients with DR that were initially treated with PRP were analyzed. The FOV of the UWFFA was significantly wider than that of the WF SS-OCTA. The quantitative measurement of the NPAs was consistent between the two methods. NPAs more than 5DA outside the panoramic OCTA imaging area were detected in 1 eye with NPDR (8.3%) and in 10 eyes with PDR (47.8%). WF SS-OCTA had high detection rates for NVDs and NVEs, with a low rate of false positives. After PRP treatment, no eyes indicated progression in the PVD stages around the macula, optical disc, or NVEs at the short follow-up.

CONCLUSION

WF SS-OCTA is clinically useful for evaluating NPAs and neovascularization in DR. PRP treatment does not induce PVD development in the short term.

Toward a New Staging System for Diabetic Retinopathy Using Wide Field Swept-Source Optical Coherence Tomography Angiography

PURPOSE OF REVIEW

For over 50 years, diabetic retinopathy (DR) has been classified by pathologic features seen on clinical examination and conventional retinal photographs. However, newer technology such as optical coherence tomography angiography (OCTA) now enables rapid acquisition of retinal structural and vascular information in a reliable, non-invasive, high-resolution fashion. Here, we highlight recent studies that have explored wide field swept-source OCTA (WF SS-OCTA) for the diagnosis and management of DR.

RECENT FINDINGS

Multiple studies have demonstrated the utility of WF SS-OCTA for detection of all clinically relevant features of DR. An updated DR staging system is proposed that leverages the advantages of WF SS-OCTA, including the ability to correlate detailed vascular and structural pathology over time with longitudinal imaging. WF SS-OCTA has tremendous potential for evaluating patients with DR. A new WF SS-OCTA-based staging system may be useful in routine clinical practice and for clinical trials.