Regression of Neovascularization after Panretinal Photocoagulation Combined with Anti-VEGF Injection for Proliferative Diabetic Retinopathy-A Review

Proliferative diabetic retinopathy (PDR) poses a significant therapeutic problem that often results in severe visual loss. Panretinal photocoagulation (PRP) has long been a mainstay treatment for this condition. Conversely, intravitreal anti-VEGF therapy has served as an alternative treatment for PDR. This review aimed to evaluate the effects of PRP combined with anti-VEGF therapy on the regression of neovascularization (NV), including functional outcomes and incidence of complications. The MEDLINE database was searched for articles evaluating regression of NV using a combination of the following terms: "proliferative diabetic retinopathy", "anti-VEGF", "panretinal photocoagulation", and "combined treatment". The search yielded a total of 22 articles. The analysis of their results indicated PRP combined with ant-VEGF therapy as superior over PRP alone in the management of PDR. Combination treatment yields better and faster regression of NV and a lower incidence of serious complications, such as vitreous hemorrhage and the need for pars plana vitrectomy. Nevertheless, complete regression of NV is not achieved in a significant proportion of patients. Further research is needed to establish the most effective schedule for intravitreal injections as an adjunct to PRP. The current literature shows that in some cases, cessation of anti-VEGF injection in combination treatment for PDR can lead to relapse of NV.

Intravitreal Conbercept

PURPOSE

To compare long-term real-world outcomes of corneal thickness (CT) alterations in proliferative diabetic retinopathy (PDR) patients treated with panretinal photocoagulation (PRP) and intravitreal conbercept (IVC).

METHODS

This retrospective study included 69 eyes of 69 patients with PDR (42 PRP and 27 IVC). Full corneal thickness (FCT), corneal epithelial thickness (CET) and corneal stromal thickness (CST) measured by anterior segment optical coherence tomography at baseline were compared between groups. These CT changes at last follow-up from baseline were also compared between groups and within each group.

RESULTS

During a mean follow-up of more than two years, the IVC group demonstrated a significantly increased corneal thickness from baseline compared to the PRP group in some areas (PRP vs. IVC: FCT 0-2 mm: -0.59 ± 9.31 vs. 5.59 ± 9.23 μm, p = 0.009; CST 0-2 mm: -2.05 ± 8.79 vs. 3.48 ± 7.52 μm, p = 0.015; CST 2-5 mm: -1.78 ± 13.27 vs. 5.68 ± 14.53 μm, p = 0.046). In within-group comparisons, a significantly increased FCT from baseline was found in the 0-2 mm area in the IVC group (p = 0.004), but no significant change was observed in the PRP group (p = 0.691). For CET changes, a significantly increased CT was observed in the 0-2 mm, 2-5 mm and 5-7 mm areas in both groups respectively (all p < 0.05). Regarding CST, an increased CT was found in the 0-2 mm area in the IVC group (p = 0.037), while a decreased trend was observed in 0-2 mm and 2-5 mm areas in the PRP group (all p > 0.05).

CONCLUSION

When using PRP or IVC in the long-term management of PDR, CT changes should be considered. This may provide evidence for corneal protection during PDR treatment.

Optical Coherence Tomography Angiography Changes in Macular Area in Patients with Proliferative Diabetic Retinopathy Treated with Panretinal Photocoagulation

BACKGROUND

The purpose of this study was to investigate the changes in macular microvasculature using optical coherence tomography angiography (OCTA) in association with functional changes in patients with proliferative diabetic retinopathy (PDR) treated with panretinal photocoagulation (PRP) with a follow up of 12 months.

METHODS

The participants in this study were 28 patients with PDR and no macular oedema, who were eligible for PRP. All participants underwent best-corrected visual acuity (BCVA) measurement, optical coherence tomography (OCT), and OCT angiography (OCTA) at baseline (before treatment) and at months 1, 6, and 12 after the completion of PRP treatment. The comparison of OCTA parameters and BCVA between baseline and months 1, 6, and 12 after PRP was performed.

RESULTS

There was a statistically significant decrease in foveal avascular zone (FAZ) area at months 6 and 12 of the follow-up period compared to baseline (p = 0.014 and p = 0.011 for month 6 and 12, respectively). Of note is that FAZ became significantly more circular 6 months after PRP (p = 0.009), and remained so at month 12 (p = 0.015). There was a significant increase in the mean foveal and parafoveal vessel density (VD) at all quadrants at the superficial capillary plexus (SCP) at month 6 and month 12 after PRP compared to baseline. No difference was noticed in VD at the deep capillary plexus (DCP) at any time-point of the follow up. BCVA remained the same throughout the follow-up period.

CONCLUSIONS

At months 6 and 12 after PRP, foveal and parafoveal VD at SCP significantly increased compared to baseline, while the FAZ area significantly decreased and FAZ became more circular.

Early-onset Neovascular Inflammatory Vitreoretinopathy Due to Two de Novo CAPN5 Mutations in Chinese Patients: A Case Series

PURPOSE

To explore the clinical and molecular characteristics, diagnosis, and treatment of early-onset autosomal dominant neovascular inflammatory vitreoretinopathy (ADNIV) in Chinese patients.

METHODS

A retrospective, interventional case series was assembled from three ADNIV patients.

RESULTS

The three ADNIV cases harbored de novo CAPN5 mutations (p.Arg289Trp and p.Leu73Val). The ages of onset ranged from 11 months to 2 years. All the cases presented with vitreous opacity and subretinal inflammatory exudations. During the postoperative follow-up, all the patients manifested with exaggerated postoperative inflammatory responses. An intravitreal Ozurdex injection could not effectively control ocular inflammation in ADNIV. Laser spots after panretinal photocoagulation were partly visible.

CONCLUSIONS

Two de novo CAPN5 mutations (p.Leu73Val and p.Arg289Trp) could cause early-onset ADNIV. Panretinal photocoagulation during vitrectomy and an intravitreal Ozurdex injection could not significantly stop the progression of subretinal exudations and ocular inflammation in early-onset ADNIV patients.

Quantitative Evaluation of Fundus Autofluorescence in Laser Photocoagulation Scars for Diabetic Retinopathy: Conventional vs. Short-Pulse Laser

Short-pulse laser is popular for its advantages like less pain. However, its effectiveness is still debated. The aim of this study was to compare fundus autofluorescence (FAF) luminosity changes of laser photocoagulation scars between the conventional laser (0.2 s) and the short-pulse laser (0.02 s) for diabetic retinopathy. Conventional and short-pulse laser photocoagulations were performed in six and seven eyes, respectively. FAF images were captured at 1, 3, 6, 12, and 18 months after the treatments. To evaluate FAF, individual gray-scale values of the laser scars adjacent to the retinal arcade vessels were recorded; then, the mean gray values of the scars were divided by the luminosity of arcade vein. The average luminosity ratio of laser scars at 1, 3, 6, 12, and 18 months were 1.51 ± 0.17, 1.26 ± 0.07, 1.21 ± 0.03, 0.95 ± 0.11, and 0.89 ± 0.05 with conventional laser and 1.91 ± 0.13, 1.50 ± 0.15, 1.26 ± 0.08, 1.18 ± 0.06, and 0.97 ± 0.04 with short-pulse laser, respectively. Findings suggest the short-pulse laser displayed delayed hypoautofluorescence progression. This implies potential postponement in post-irradiation atrophic changes, as well as metabolic amelioration delay in the ischemic retina, when compared to conventional laser treatment.

Retinal vein changes in patients with high-risk proliferative diabetic retinopathy treated with conbercept and panretinal photocoagulation co-therapy: a cohort study

Objective

This study aimed to observe and compare retinal vein diameter changes and other essential indicators in patients with high-risk proliferative diabetic retinopathy (PDR) treated with intravitreal injection of conbercept (IVC) combined with panretinal photocoagulation (PRP) versus PRP monotherapy.

Methods

A retrospective analysis was conducted on data from patients with high-risk PDR who received specific treatment and were followed up for 24 months. Among 82 patients with high-risk PDR, 50 eyes received PRP combined with IVC, whereas 32 eyes received PRP alone. During the 24-month follow-up period, changes in best-corrected visual acuity (BCVA), central foveal thickness (CFT), retinal vein diameter, number of microaneurysms (MA), neovascularization (NV) area, hard exudate (HE) area, size of the foveal avascular zone (FAZ), superficial capillary plexus (SCP) blood flow density, and adverse effects were recorded and compared between the two groups at baseline and at 6, 12, 18, and 24 months after treatment. The relationship between each observation index and vein diameter was also analyzed.

Results

During the 24-month follow up, significant improvements in the BCVA, CFT, retinal vein diameter, number of MAs, NV area, HE area, FAZ, and SCP were observed in the IVC+PRP group after treatment. The PRP group only showed significant reductions in NV and HE areas. The IVC+PRP group showed significant superiority over the PRP group in improving the vein diameter, number of MA, and HE area. However, no statistically significant difference in NV area reduction was found between the groups.

Conclusion

In the treatment of high-risk PDR, IVC+PRP therapy has a significant advantage over PRP monotherapy. IVC+PRP therapy may reverse diabetes-induced retinal vein changes, restoring morphology and function.

Retinal laser - Protocols and practical tips

Background

Many a young doctors in training find retinal laser photocoagulation a daunting task. However, if correct protocols are followed and checklists are observed, then it is not difficult to have a successful laser sitting with a happy patient. Most of the complications can be avoided with correct settings and techniques.

Purpose

To enumerate the basic protocols of retinal laser photocoagulation and provide practical tips including laser settings and checklists for hassle-free laser experience.

Synopsis

Laser settings for a pan-retinal photocoagulation (PRP) for proliferative diabetic retinopathy differ from those for a focal laser for macular edema. A fill in PRP is indicated when an active Proliferative diabetic retinopathy (PDR) is seen after the initial PRP is completed. The settings and protocols for laser photocoagulation for lattice degeneration are different, and various techniques of barrage laser are discussed. Practical tips and checklists are given, which will not be found in any textbooks.

Highlights

Animated illustrations and fundus photos are used to explain the correct techniques of performing laser photocoagulation in different indications and scenarios. Detailed instructions and checklists are provided, which can be very useful to avoid complications and medicolegal problems. The practical tips and guidelines in an easy-to-understand manner make this video highly educational for the novice retinal surgeons who want to perfect their technique of retinal laser photocoagulation.

Video Link

https://youtu.be/saQ4s49ciXI.

Aflibercept for long-term treatment of diabetic macular edema and proliferative diabetic retinopathy: a meta-analysis

Purpose

This meta-analysis compared the long-term (12 months or 24 months) efficacy and safety of intravitreal aflibercept injection (IAI) for diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR).

Methods

We selected 16 randomized controlled trials (RCTs) performed after 2015 that had a minimum of 12 months and up to 24 months of treatment and conducted a meta-analysis with Review Manager version 5.3. Visual acuity (VA), central subfield thickness (CST) and adverse events were the outcomes selected for evaluation from the eligible studies.

Results

Based on 16 RCTs, we evaluated a total of 7125 patients. For PDR and severe DME with poor baseline vision, after a minimum of 12 months and up to 24 months of treatment, the aflibercept treatment group obtained better VA improvement than the focal/grid laser photocoagulation treatment group (MD=13.30; 95%CI: 13.01~13.58; P<0.001) or other treatments (ranibizumab, focal/grid laser photocoagulation, PRP, et al.) group (MD=1.10; 95%CI: 1.05~1.16; P<0.001). In addition, the aflibercept treatment group got higher CST reduction than the focal/grid laser photocoagulation treatment (MD=-33.76; 95%CI: -45.53 ~ -21.99; P<0.001) or other treatments (ranibizumab, focal/grid laser photocoagulation, et al.) group (MD=-33.76; 95%CI: -45.53 ~ -21.99; P<0.001). There was no significant difference in the overall incidence of ocular and non-ocular adverse events in each treatment group.

Conclusions

This meta-analysis showed that the advantages of IAI are obvious in the management of DME and PDR with poor baseline vision for long-term observation (a minimum of 12 months and up to 24 months) with both VA improvement and CST reduction. Applied IAI separately trended to be more effective than panretinal photocoagulation separately in VA improvement for PDR. More parameters should be required to assess functional and anatomic outcomes.

Outcomes of Pars Plana Vitrectomy with Panretinal Photocoagulation for Treatment of Proliferative Diabetic Retinopathy Without Retinal Detachment: A Seven-Year Retrospective Study

Objective

To review clinical outcomes of patients with proliferative diabetic retinopathy (PDR) and vitreous hemorrhage (VH) who underwent pars plana vitrectomy (PPV) with endolaser panretinal photocoagulation (PRP) without retinal detachment (RD) repair.

Methods

Retrospective chart review of the rate of postoperative clinical findings and visual acuity in patients with PDR from May 2014 to August 2021.

Results

Pars plana vitrectomy with endolaser PRP was performed in 81 eyes of 81 patients (mean age of 62.1 ± 10.5 years). At a median follow-up of 18 months, mean Snellen best-corrected visual acuity (BCVA) significantly improved from 20/774 preoperatively to 20/53 at last follow-up (P < 0.001). Postoperative complications and clinical findings included VH (12.3%), diabetic macular edema (DME) (12.3%), ocular hypertension (8.6%), RD (4.9%), and need for additional PPV (6.2%). Eyes with PRP performed within 6 months before surgery had a lower frequency of developing postoperative VH (5.3%) compared to eyes that received PRP more than 6 months before surgery (27.3%, P = 0.04). Eyes that received preoperative anti-vascular endothelial growth factor (VEGF) treatment (2.0%) had a lower frequency of postoperative VH compared to eyes that did not receive anti-VEGF treatment (14.3%, P = 0.04). Eyes that received intraoperative sub-tenon triamcinolone acetonide developed postoperative DME (4.0%) less frequently than eyes that did not receive sub-tenon triamcinolone acetonide (26.7%, P = 0.04).

Conclusion

In patients with PDR and VH, PPV with PRP yielded significant improvements in visual acuity and resulted in overall low rates of recurrent postoperative VH. Preoperative anti-VEGF and PRP laser treatment were associated with lower rates of postoperative VH. Furthermore, intraoperative use of sub-tenon triamcinolone acetonide was associated with a lower rate of postoperative DME. Pars plana vitrectomy with endolaser PRP in conjunction with the aforementioned pre- and intraoperative therapies is an effective treatment for patients with PDR and VH.

Aqueous Flare and Intraocular Pressure in the Early Period Following Panretinal Photocoagulation in Patient with Proliferative Diabetic Retinopathy

Objectives

The aim of the study was to investigate the effect of panretinal photocoagulation (PRP) on aqueous flare and intraocular pressure (IOP) in the early period.

Methods

Eighty-eight eyes of 44 patients were included in the study. The patients underwent a full ophthalmologic examination including the best corrected visual acuity, IOP measured by Goldmann applanation tonometry, biomicroscopy, and dilated fundus examination before PRP. Aqueous flare values were measured by the laser flare meter. Aqueous flare and IOP values were repeated in both eyes at the 1^st and 24^th h after PRP. The eyes of the patients who underwent PRP were included in the study as the study group, and the other eyes as the control group.

Results

In eyes treated with PRP, 1^st h (19.44 pc/ms) and 24^th h (18.53 pc/ms) aqueous flare values were statistically higher than before PRP (16.66 pc/ms) (p<0.05). In the study eyes which were similar to the control eyes before PRP, the aqueous flare was higher at the 1^st and 24^th h after PRP compared to control eyes (p<0.05). The mean IOP at the 1^st h (18.69 mmHg) after PRP in study eyes was higher than both pre-PRP (16.25 mmHg) and post-PRP 24^th h (16.12 mmHg) IOP values (p<0.001). At the same time, the IOP value at the 1^st h after PRP was higher than the control eyes (p=0.001). No correlation was observed between aqueous flare and IOP values.

Conclusion

An increase in aqueous flare and IOP values was observed after PRP. Besides, the increase in both values starts even in the 1^st h, and the values at 1^st h are the highest values. At the 24^th h, while IOP values return to baseline, aqueous flare values are still high. In patients who may develop severe intraocular inflammation or cannot tolerate increased IOP (such as previous uveitis, neovascular glaucoma, or severe glaucoma), control should be performed at the 1^st h after PRP to prevent irreversible complications. Furthermore, the progression that may develop in diabetic retinopathy due to increased inflammation should also be kept in mind.

Refractive Changes among Diode Laser-treated Retinopathy of Prematurity Patients: A Retrospective Study

PURPOSE

The purpose of this study was to assess the refractive outcomes of patients who underwent indirect laser photocoagulation for prethreshold type 1 retinopathy of prematurity (ROP) and high-risk type 2 prethreshold ROP in comparison to conservatively managed low-risk prethreshold type 2 ROP.

METHODS

A retrospective analysis was carried out on infants screened for ROP between the years 2015 and 2020. Surviving children who had developed ROP in one or both eyes and received diode laser photocoagulation and those with conservatively managed regressed type 2 ROP who underwent at least one cycloplegic retinoscopy were included in the study.

RESULTS

A total of 144 patients were screened for ROP between 2015 and 2020 at our institution. One hundred and thirty patients (260 eyes) fulfilled the study criteria and were included in this study. The treated group consisted of 132 eyes of 66 infants, of which 38 (14.6%) eyes had prethreshold type 1 ROP while 94 (36.2%) eyes had high-risk prethreshold type 2. The nontreated control group consisted of 128 (49.2%) eyes of 64 infants with low-risk type 2 prethreshold ROP. Earlier prematurity was found to be a significant determinant of the mean change in spherical equivalent among different gestational age groups (P = 0.035). In our cohort, we found that myopia is significantly related to Zone II ROP in comparison to Zone III ROP in the treated eyes (22% vs. 9%) (P = 0.002). No statistically significant difference was found in the final refraction among the treated eyes in relation to the birth weight or stage of prematurity.

CONCLUSION

In the present study, the majority of patients who were treated with diode laser for ROP had favorable anatomical and refractive outcomes. In contrast to previous studies that had suggested a trend toward myopia in laser-treated patients, in our study, the majority (71%) were hyperopes. This study suggests that other factors such as the stage and zone of ROP possibly contribute more to the development of myopia than the laser photocoagulation itself.

Evaluating Adherence to Diabetic Retinopathy Care in an Urban Ophthalmology Clinic Utilizing the Compliance With Annual Diabetic Eye Exams Survey

Introduction The objective of this study was to identify barriers that affect adherence to the management of diabetic retinopathy (DR) in an urban ophthalmology clinic. Patient beliefs regarding diabetic eye care, transportation to the eye clinic, the COVID-19 pandemic, and treatment with panretinal photocoagulation (PRP) or anti-vascular endothelial growth factor (anti-VEGF) injections were investigated. Materials and methods The original Compliance with Annual Diabetic Eye Exams Survey (CADEES) included 44 statements designed with a 5-point Likert scale to assess patients' beliefs and understanding of their eye health and the importance of diabetic eye examinations. This survey was modified to include additional statements regarding the COVID-19 pandemic and free-response questions about transportation barriers and patients' subjective experiences with PRP or anti-VEGF injections. A total of 365 patients with a diagnosis of any stage of DR from SLUCare Ophthalmology were identified as potential participants to complete the telephone survey. Patients were classified as non-adherent if they did not have a dilated eye examination within the past year, missed a scheduled follow-up appointment for DR care within the past year, or missed an appointment for anti-VEGF injections or PRP. The mean Likert scores for each CADEES statement were compared between the adherent and non-adherent groups using independent samples t-tests. Demographics and clinical indicators were also reported and compared between the two groups. Results Out of 365 patients, 68 completed the modified CADEES. Twenty-nine patients were adherent, and 39 patients were non-adherent. Results from six of the 54 CADEES statements were significantly different between the adherent and non-adherent groups. These statements addressed patients' perception of their eye health, self-confidence in making an eye appointment, knowing someone with diabetic eye complications, self-confidence in controlling blood sugar, ability to use public transportation during the COVID-19 pandemic, and prioritizing eye health during the pandemic. There were no significant differences in clinical indicators or demographics between the adherent and non-adherent groups. Of the participants, 39.7% offered reasons for why transportation to the eye clinic was difficult. Patients suggested three novel reasons for missing eye appointments that were not specifically addressed in the CADEES. Fourteen unique barriers were reported for non-adherence with PRP or anti-VEGF injections. Conclusions The CADEES is a thorough tool for evaluating social barriers impacting adherence with DR appointments in an urban ophthalmology clinic. The survey did not identify any clinical or demographic risk factors for non-adherence in this patient population. Decreased patient self-efficacy may lead to non-adherence with the management of DR. The COVID-19 pandemic impacted the adherence of a small percentage of patients.

Morphological Changes in the Foveal Avascular Zone after Panretinal Photocoagulation for Diabetic Retinopathy Using OCTA: A Study Focusing on Macular Ischemia

Background and objectives: This study aimed to analyze the morphological changes in the foveal avascular zone (FAZ) after panretinal photocoagulation (PRP) in patients with diabetic retinopathy, with a particular focus on the presence or absence of comorbid diabetic macular ischemia (DMI), using optical coherence tomography angiography (OCTA). Materials and Methods: Treatment-naïve 25 eyes of 16 patients who received PRP were examined in this retrospective case series. FAZ area, perimeter, and circularity were calculated on a 3 × 3-mm en-face OCTA image before PRP (baseline) and 1 and 3 months after PRP. The patients were divided into two groups according to coexisting DMI, and each group was statistically analyzed. Results: In patients with DMI (9 eyes), FAZ area significantly decreased from the baseline to 3 months after PRP (0.86 ± 0.56 to 0.61 ± 0.31 mm², p = 0.018), whereas FAZ perimeter and circularity remained unchanged following treatment (p = 0.569 and 0.971, respectively). In patients without DMI (16 eyes), FAZ parameters did not show statistically significant changes across the 3-month follow-up period. Conclusion: PRP significantly reduces FAZ area in patients with DMI.

VEGF-targeting drugs for the treatment of retinal neovascularization in diabetic retinopathy

Diabetic retinopathy (DR) is the most common microangiopathic complication of diabetes mellitus, representing a major cause of visual impairment in developed countries. Proliferative DR (PDR) represents the last stage of this extremely complex retinal disease, characterized by the development of neovascularization induced by the abnormal production and release of vascular endothelial growth factor (VEGF). The term VEGF includes different isoforms; VEGF-A represents one of the most important pathogenic factors of DR. Anti-VEGF intravitreal therapies radically changed the outcome of DR, due to combined anti-angiogenic and anti-edematous activities. Nowadays, several anti-VEGF molecules exist, characterized by different pharmacological features and duration. With respect to PDR, although anti-VEGF treatments represented a fundamental step forward in the management of this dramatic complication, a big debate is present in the literature regarding the role of anti-VEGF as substitute of panretinal photocoagulation or if these two approaches may be used in combination. In the present review, we provided an update on VEGF isoforms and their role in DR pathogenesis, on current anti-VEGF molecules and emerging new drugs, and on the current management strategies of PDR. There is an overall agreement regarding the relative advantage provided by anti-VEGF, especially looking at the management of PDR patients requiring vitrectomy, with respect to laser. Based on the current data, laser approaches might be avoided when a perfectly planned anti-VEGF therapeutic strategy can be adopted. Conversely, laser treatment may have a role for those patients unable to guarantee enough compliance to anti-VEGF injections.Key messagesVEGF increased production, stimulated by retinal hypoperfusion and ischaemia, is a major pathogenic factor of neovascular complication onset in diabetic retinopathy and of DR stages progression.Nowadays, several anti-VEGF molecules are available in clinical practice and other molecules are currently under investigation. Each anti-VEGF molecule is characterized by different targets and may interact with multiple biochemical pathways within the eye.All the data agreed in considering anti-VEGF molecules as a first line choice for the management of diabetic retinopathy. Laser treatments may have a role in selected advanced cases and for those patients unable to guarantee enough compliance to intravitreal treatments schemes.

Vision-Related Quality of Life and Treatment Satisfaction Following Panretinal Photocoagulation in Diabetic Retinopathy-A Panel Study

Background and Objectives: The aim of the study was to evaluate vision-related quality of life (VR-QOL) and treatment satisfaction (TS) in patients with diabetic retinopathy treated with panretinal photocoagulation (PRP). Material and Methods: The panel study included 95 patients who underwent PRP for diabetic retinopathy. Eligible patients with no history of previous PRP were interviewer-administered the National Eye Institute Visual Function Questionnaire (NEI VFQ-25) and Retinopathy Treatment Satisfaction Questionnaire (RetTSQ) beforehandand one month after the last session of laser application. The study was conducted between June 2017 and June 2019 at tertiary care center in Serbia, Belgrade. We assessed pre- to post-PRP values of the composite score and subscale scores of VFQ-25 and RetTSQ, using a paired samples t-test. Univariate logistic regression was used to analyze the relationship between binary outcomes and potential predictors. Multivariate regression included predictors from univariate analyses that were statistically significant. Results: The mean VFQ-25 composite score was 65.4 ± 17.4 before and 63.3 ± 19.5 after PRP (p = 0.045). Subscale analysis showed that two of the 11 items achieved a significant decrease after laser application (general vision and dependency). The mean RetTSQ score at baseline was 60.0 ± 11.8 and at the exit visit was 60.3 ± 12.3 (p = 0.858). Sub-scale analysis showed significant deterioration for five of the 13 items. Multivariate logistic regression found that significant predictor of VFQ-25 composite score reduction was fewer laser burns (p = 0.002) while significant predictor of RetTSQ total score reduction was presence of hyperlipidaemia (p = 0.021). Conclusion: The use of vision-related quality of life and treatment satisfaction questionnaires in conjunction with clinical examination, appears to provide a more comprehensive overview of an individual's daily well-being following PRP. Laser treatment for diabetic retinopathy leads to deterioration of some of the patients' perceived VR-QOL and TS. Health-care providers should inform patients about their treatment options and together decide which therapeutic method is best for them.

Optociliary Shunt Vessels or Neovascularisation of the Optic Disc: Fluorescein Angiography Versus Optical Coherence Tomography Angiography

A 56-year-old man with a history of gallbladder carcinoma, hypothyroidism and hypertension was examined by us after developing marked visual loss in his left eye. A left ischaemic type of central retinal vein occlusion (CRVO) with macular oedema was diagnosed. Three months later, a non-ischaemic type of CRVO with no macular oedema developed in his right eye. While the left eye received five intravitreal ranibizumab injections and panretinal photocoagulation, the right central retinal vein occlusion improved spontaneously without any treatment. Ten months after his first visit we noticed optociliary shunt vessel formation in the right eye and neovascularisation of the optic disc in the left eye. Fluorescein angiography and optical coherence tomography angiography were performed at the same visit. The place of fluorescein angiography and optical coherence tomography angiography in distinguishing the optociliary shunt vessel from neovascularisation of the optic disc is discussed.

Evaluation of macular perfusion in eyes with proliferative diabetic retinopathy using optical coherence tomography - Angiography following panretinal photocoagulation

AIM

The aim of this study is to evaluate the effect of panretinal photocoagulation (PRP) on macular perfusion using optical coherence tomography-angiography (OCT-A) in eyes with proliferative diabetic retinopathy (PDR) by assessing the vessel density (VD) and the size of the foveal avascular zone (FAZ) of the superficial capillary plexus (SCP) and the deep capillary plexus (DCP), before and after PRP.

SETTINGS AND DESIGN

Prospective interventional study.

SUBJECTS AND METHODS

Twenty-nine eyes of 17 patients with PDR underwent a measurement of best-corrected visual acuity (BCVA) and were imaged using OCT and OCT-A at baseline and 6-months of follow-up. Patients received three sittings of PRP using frequency-doubled neodymium-doped yttrium aluminum garnet laser.

STATISTICAL ANALYSIS USED

The OCT-A variables were analyzed using generalized estimating equations.

RESULTS

BCVA was unchanged at 6-months follow-up (P = 0.09). FAZ of SCP and DCP (P = 0.28 and 0.89, respectively), VD at foveal SCP (P = 0.08), foveal DCP (P = 0.05), parafoveal SCP (P = 0.13), and parafoveal DCP (P = 0.07) showed no statistically significant difference at 6 months post PRP.

CONCLUSIONS

OCT-A parameters were not significantly affected by PRP at 6-months follow-up indicating no alteration in macular perfusion. Further analyses with larger samples and longer duration are warranted to confirm our results.

Correlation of Optical Coherence Tomography Angiography Characteristics with Visual Function to Define Vision-Threatening Diabetic Macular Ischemia

The thresholds of macular microvasculature parameters associated with mild visual impairment in diabetic macular ischemia (DMI) patients are unclear. Therefore, this prospective observational study is aimed at demonstrating the optical coherence tomography angiography parameters that best correlate with mild visual impairment (<70 Early Treatment Diabetic Retinopathy Study (ETDRS) letters, Snellen equivalent 20/40) in DMI. The study was completed at the Moorfields Eye Hospital from December 2019 to August 2021. A total of 123 eyes of 87 patients with stable-treated proliferative diabetic retinopathy following panretinal photocoagulation were recruited. DMI was defined as an irregular foveal avascular zone (FAZ) area ≥ 0.5 mm2 or a smaller FAZ area with parafoveal capillary dropout in at least one quadrant. The analysis showed that the whole image deep vascular complex vessel density (DVC VD) in the 3 × 3 mm area had the best discriminatory ability to identify participants with mild visual impairment at 41.9% (area under the curve = 0.77, sensitivity 94%, specificity 54%, likelihood ratio [LR] = 2.04), and the FAZ area had the greatest post-test LR = 4.21 at 0.64 mm2. The 3 × 3 mm whole image DVC VD and FAZ area cutoffs are useful for screening vision-threatening DMI, but DVC VD has low specificity.

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.

Effectiveness of Panretinal Photocoagulation Plus Intravitreal Anti-VEGF Treatment Against PRP Alone for Diabetic Retinopathy: A Systematic Review With Meta-Analysis

OBJECTIVE

To compare the efficacy and safety of panretinal photocoagulation (PRP) combined with intravitreal anti-vascular endothelial growth factor (anti-VEGF) against PRP monotherapy for diabetic retinopathy (DR).

METHODS

We searched Pubmed, Cochrane Library, Web of Science, Embase, and Science Direct Register of Controlled Trials from April 2011 to January 2021 to identify the randomized trials that compared the efficacy and safety between PRP combined with intravitreal anti-VEGF and PRP monotherapy for DR. We searched in the following databases between April 2011 and January 2021: Pubmed, Cochrane Library, Web of Science, Embase, and Science Direct without any restriction of countries or article type. The outcome measures were the best-corrected visual acuity (BCVA), neovascularization on the disc (NVD), neovascularization elsewhere (NVE), central macula thickness (CMT), and total retinal volume over time (FAS), and we also observed the adverse events (AEs) between the two groups.

RESULTS

A total of 351 studies were identified, of which 11 studies were included in this meta-analysis (N = 1,182 eyes). Compared with PRP monotherapy, PRP plus anti-VEGF combination treatment produced a mean reduction in BCVA in units of logMAR of -0.23 [95% CI -0.32, -0.15] or a mean improvement in BCVA in units of letters of 4.99 [95% CI 3.79, 6.19], and also yielded a mean reduction in NVD of -28.41 [95% CI -30.30, -26.52], in NVE of -1.33 [95% CI -1.52, -1.14], in CMT of -1.33 [95% CI -1.52, -1.14], or in total FAS. No significant difference was observed on the risk of AEs as vitreous hemorrhage, elevation in intraocular pressure, and cataract between the two different treatments.

CONCLUSION

PRP with anti-VEGF combination treatment can achieve the ideal efficacy on DR by improving BCVA and NV regression, with no potential increased incidence of AEs, which proves that the combination therapy is an efficient therapeutic strategy that could improve the management of patients with DR.

A comparison between the therapeutic effects of Conbercept combined with panretinal photocoagulation and panretinal photocoagulation monotherapy for high-risk proliferative diabetic retinopathy

OBJECTIVE

To compare the therapeutic effects of the administration of intravitreal Conbercept (IVC) plus panretinal photocoagulation (PRP) to that of PRP monotherapy in patients with high-risk proliferative diabetic retinopathy (PDR).

METHODS

In this retrospective consecutive case series, we analyzed the data on high-risk PDR patients followed up for 12 months. Patients were divided into two groups: the IVC+PRP group and the PRP monotherapy group. Patients in the IVC+PRP group were initially administered 3 IVC injections and PRP, while patients in the PRP monotherapy group received PRP only. Depending on the grouping criteria, patients in both groups were administered either IVC+PRP or PRP only if the neovascularization (NV) did not regress. From the initiation to month 12 of treatment, we recorded and compared the data on the NV regression rate, improvement in best-corrected visual acuity (BCVA), laser spots, changes in central macular thickness (CMT), complications, and the need for vitrectomy for all patients.

RESULTS

In this study, 79 eyes of 58 patients in the IVC+PRP group and 86 eyes of 60 patients in the PRP monotherapy group were included. During the follow-up of 12 months, the number of eyes with complete regression, partial regression, and no regression or increase in NV were 56 (70.88%), 23 (29.12%), and 0 (0%) in the IVC+PRP group and 13 (15.12%), 50 (58.14%), and 23 (26.74%) in the PRP group (p < 0.001). The BCVA was significantly higher and CMT was lower in the patients of the IVC+PRP group than in the PRP monotherapy group at 3, 6, and 12 months of follow-up (p < 0.05). The mean number of laser spots was lower in the patients of the IVC+PRP group than in the PRP group (1,453 ± 87 spots vs. 2,267 ± 94 spots, p < 0.05). A significantly lower percentage of patients in the IVC+PRP group underwent vitrectomy than that in the PRP group (7 (8.86%) vs. 27 (31.40%), p < 0.001).

CONCLUSION

High-risk PDR patients treated with IVC + PRP showed a higher rate of NV regression, more effective improvement in the BCVA, and lower vitrectomy rate compared to those who were administered PRP monotherapy.

OCTA in macular intraretinal microvascular abnormalities: Retinal vascular density remodeling after panretinal photocoagulation

PURPOSE

To describe a case of macular intraretinal microvascular abnormality (IRMA) detected with Optical Coherence Tomography Angiography (OCTA) and to show its remodeling and vascular density changes after panretinal photocoagulation (PRP) during an 18-month follow-up.

METHODS

Case report.

RESULTS

A 22-year-old female patient with proliferative diabetic retinopathy was found to have a small hyperreflective formation with posterior shadow cone and signal flow, located at the temporal margin of the fovea avascular zone (FAZ), identified as macular IRMA with OCTA. Her best-corrected-visual acuity was 20/20. Four months later the macular IRMA was larger and, in its context, there was also an increase in the flow area in B-scan. The patient underwent PRP and after 18 months we observed a regression of macular IRMA and an increase in the superficial capillary plexus vessel density in all sectors in comparison to baseline.

CONCLUSION

OCTA is a non-invasive tool that recognize macular IRMA in diabetic retinopathy patient and it could be helpful to follow their qualitative and quantitative vascular evolution over time.

Long-Term Retinal Neurovascular and Choroidal Changes After Panretinal Photocoagulation in Diabetic Retinopathy

Purpose: To evaluate the long-term retinal microvascular, neural, and choroidal changes in the patients with severe nonproliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR) following panretinal photocoagulation (PRP).

Methods: Forty-five eyes of 28 patients with treatment-naive severe NPDR and PDR were included and followed for 12 months after PRP. Microvascular and neural changes in the macular and peripapillary areas were assessed by using optical coherence tomography angiography. Subfoveal choroidal thickness (SFCT) was measured by using optical coherence tomography. A Linear mixed-effects model was used to highlight the differences for the variables after adjusting for sex, age, and axial length.

Results: Compared to baseline, there were no statistical differences in the best corrected visual acuity (BCVA), macular and peripapillary vessel density (VD), and SFCT following PRP. Macular thickness significantly increased at 1 and 3–6 months after PRP (p < 0.05), while the peripapillary retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thickness significantly increased at 1 month postoperatively (p < 0.01). Global loss volume and focal loss volume significantly decreased at the same time point (p < 0.05).

Conclusion: The unchanged BCVA, VD, the thickness of RNFL and GCC, and SFCT during the 12-month follow-up period suggest that PRP may prevent the retinal neurovascular and choroidal damage.

Neovascular Glaucoma Progress and Impact of Therapeutic Intervention in Saudi Arabia

Purpose: This study aimed to present the outcomes of the therapeutic interventions for neovascular glaucoma (NVG) between 2002 and 2012 at a tertiary eye hospital in Saudi Arabia.

Methods: A retrospective chart review of the patients with NVG treated in the last 10 years at King Khaled Eye Specialist Hospital was carried out. The demographics, visual acuity, and intraocular pressure (IOP) at the baseline were compared to that, at last, follow-up. The clinical course of treated eyes and causes for poor vision were reviewed.

Results: Among 597 eyes with NVG, the mean IOP at presentation was 32 mmHg. A total of 335 eyes (56.1%) were treated with pan-retinal photocoagulation (PRP). In 459 (77%) eyes, IOP was controlled with medications or different surgeries. The vision on the last follow-up was 20/20 to 20/40 in 19 (3%) eyes, 20/50 to 20/200 in 67 (11%) eyes, <20/200 to 20/400 in 267 (45%) eyes, and <20/400 in 225 (38%) eyes. Nineteen eyes were soft/enucleated. In 45 (8%, 95% CI 6-10) eyes vision improved. The IOP was reduced to <22 mmHg in 369 (62%, 95% CI 58.2-65.9) eyes, 23-30 mmHg in 69 (12%) eyes and was > 31 mmHg in 102 (17%) eyes. In 26 (3.7%) eyes, ocular hypotony was noted. The causes of poor vision included retinal ischemia (n=75, 13%), optic nerve head cupping (n=104, 17%), retinal detachment (n= 42, 7%) and other (n=17, 3%).

Conclusion: The NVG is a serious ocular ischemic complication. Prompt therapy maintained or improved the vision and controlled IOP in 50% and more cases.

Simultaneous pars plana vitrectomy, panretinal photocoagulation, cryotherapy, and Ahmed valve implantation for neovascular glaucoma

AIM

To describe and evaluate the efficacy of Ahmed glaucoma valve implantation (AGV) combined with pars plana vitrectomy (PPV) in a single surgical act for the treatment of advanced neovascular glaucoma (NVG).

METHODS

Retrospective observational case series included 51 eyes from 50 patients with severe NVG treated with PPV, AGV, and panretinal photocoagulation and/or cryotherapy in a single surgical act during a 13-year period (2005-2018). Preoperative, intraoperative and postoperative data at day 1 and months 1, 3, 6, 21, and 24 were systematically collected. Definition of surgical success was stablished at IOP between 6 and 21 mm Hg with or without topical treatment.

RESULTS

Main indications for surgery were NVG secondary to proliferative diabetic retinopathy (39.2%) and central retinal vein occlusion (37.3%). Mean (±SD) preoperative IOP was 42.0±11.2 mm Hg decreasing to 15.5±7.1 mm Hg at 12mo and 15.8±9.1 mm Hg at 24mo of follow up. Cumulative incidence of success of IOP control was 76.0% at first postoperative month, reaching 88.3% at 6mo. Prevalence of successful IOP control at long term was 74.4% at 12mo and 71.4% at 24mo. Eye evisceration for unsuccessful NVG management was required in 1 case (2.0%).

CONCLUSION

Combination of AGV implantation and PPV in a single act may be a suitable option for severe forms of NVG in a case-by-case basis for effective IOP control and a complete panretinal photocoagulation.

Intravitreal anti-vascular endothelial growth factors, panretinal photocoagulation and combined treatment for proliferative diabetic retinopathy: a systematic review and network meta-analysis

PURPOSE

To conduct a systematic review with network meta-analysis (NMA) of randomized clinical trials (RCTs) comparing panretinal photocoagulation (PRP) versus anti-vascular endothelial growth factor (VEGF) treatment alone or in combination with PRP, for proliferative diabetic retinopathy (PDR).

METHODS

PubMed, Medline and Embase databases were searched for RCTs comparing PRP versus intravitreal anti-VEGF therapy and/or combined PRP and intravitreal anti-VEGF for PDR. The primary outcome measures were the mean best corrected visual acuity (BCVA) change and the regression of neovascularization. Mean change of central macular thickness (CMT), the subgroup analyses of patients without diabetic macular oedema (DME) and the rate of vitreous haemorrhage and vitrectomy were secondary outcomes. Frequentist NMAs were performed.

RESULTS

Twelve RCTs were included. For the 12-month mean BCVA change, NMA showed a better visual outcome in both the anti-VEGF group and combined group compared to PRP [anti-VEGF vs PRP, mean difference (MD) = 3.42; standard error (SE) = 1.5; combined vs PRP, MD = 3.92; SE = 1.65], with no difference between combined group and anti-VEGF (MD = -0.50; SE = 1.87). No difference in neovascularization regression was found between PRP and anti-VEGF alone or in combination with PRP, but there was significant inconsistency (p = 0.016). Subgroup analyses in patients without DME yielded no difference for the 12-month visual outcome between the three interventions, but with significant inconsistency (p = 0.005).

CONCLUSION

This NMA showed limited evidence of comparable efficacy in terms of neovascularization regression between PRP and anti-VEGF therapy alone or in combination with PRP, but better visual outcomes were associated with anti-VEGF use. Intravitreal anti-VEGF therapy could be a valid therapeutic option in association with PRP.

Factors Influencing Threshold Energy in Subthreshold Photocoagulation for Diabetic Macular Edema

Background

Subthreshold photocoagulation is one of the treatments for diabetic macular edema. However, the range of adequate laser energy that can be used for subthreshold photocoagulation is very restricted. Therefore, determination of the titration settings for the threshold energy is an essential part of the subthreshold-photocoagulation procedure. This study examined factors influencing the threshold energy used in subthreshold photocoagulation for diabetic macular edema.

Methods

For 20 consecutive cases (29 eyes) who had received treatment using Endpoint Management (EpM) between April 2019 and June 2020 for persistent diabetic macular edema after completion of panretinal photocoagulation, multiple regression analysis was used to examine factors influencing threshold energy.

Results

Analysis evaluating all the surgical procedures (n=150) determined there was statistical significance for a history of vitrectomy and cataract surgery, central macular thickness, interval from completion of panretinal photocoagulation, superior 6 mm subfield, and nasal 6 mm subfield. Further analysis examined surgical procedures that had been done in patients with a history of vitrectomy and cataract surgery (n=116). This analysis showed that central macular thickness, axial length, interval from completion of panretinal photocoagulation, and HbA_1c were all statistically significant factors.

Conclusion

Threshold energy for diabetic macular edema was significantly influenced by a history of vitrectomy and cataract surgery, central macular thickness, and interval between the completion of panretinal photocoagulation and initial EpM. Transparency of ocular media and intraocular inflammation were speculated to be associated with these results.

Clinical efficacy and acceptability of panretinal photocoagulation combined with conbercept for patients with proliferative diabetic retinopathy: A protocol for systematic review and meta-analysis

BACKGROUND

Although conbercept has been used for other diseases associated with new vascular formation, the effect of single-dose conbercept in combination with proliferative diabetic retinopathy (PDR) have not been established. We thus conducted this protocol for systematic review and meta-analysis to compare the efficacy and acceptability of panretinal photocoagulation (PRP) associated with intravitreal conbercept injections versus PRP alone in the treatment of patients with PDR.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols reporting guidelines and the recommendations of the Cochrane Collaboration were followed to conduct this study. Reviewers will search the PubMed, Cochrane Library, Web of Science, and EMBASE online databases using the key phrases "panretinal photocoagulation," "conbercept," and "proliferative diabetic retinopathy" for all cohort studies published up to May 2021. The studies on cohort study focusing on PRP + conbercept and PRP alone for PDR patients will be included in our meta-analysis. At least one of the following outcomes should have been measured: PRP completion rate, proportion of eyes with visual gain/loss, central macular thickness, and incidence of complication. Review Manager software (v 5.4; Cochrane Collaboration) is used for the meta-analysis.

RESULTS

It was hypothesized that intravitreal conbercept plus PRP was more effective than PRP alone.

OSF REGISTRATION NUMBER

10.17605/OSF.IO/HCQ2S.

Clinical efficacy of anti-vascular endothelial growth factor versus panretinal photocoagulation for patients with proliferative diabetic retinopathy: A protocol for systematic review and meta-analysis

BACKGROUND

The argument on the optimal treatment for patients with proliferative diabetic retinopathy (PDR) remains to be resolved. Therefore, the primary objective of the present study was to evaluate the clinical efficacy of anti-vascular endothelial growth factor (anti-VEGF) therapy versus panretinal photocoagulation (PRP) for patients with PDR.

METHODS

Two independent investigators followed The Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guidelines and the recommendations of the Cochrane Collaboration to conduct this meta-analysis. The electronic databases of EMBASE, PubMed, Cochrane Library, and Web of Science were searched from the inception to April 2021 using the following key terms: "proliferative diabetic retinopathy," "anti-vascular endothelial growth factor," and "panretinal photocoagulation," for all relevant studies. We identified literature that met the following inclusion criteria: patients with PDR; studies focusing on assessing anti-VEGF therapy and PRP; the following outcome measures must be shown: anatomical outcomes, including complete regression and recurrence of neovascularization, mean change in best corrected vision acuity from baseline to the end of follow-up period. The Cochrane risk of bias tool was used to evaluate the risk of bias of included randomized clinical trials by 2 independent reviewers.

RESULTS

This protocol will provide a reliable theoretical basis for the following research.

TRIAL REGISTRATION NUMBER

10.17605/OSF.IO/UHYDR.

Clinical efficacy of intravitreal aflibercept injection versus vitrectomy with panretinal photocoagulation for patients with proliferative diabetic retinopathy: A protocol for systematic review and meta-analysis

BACKGROUND

In the current literature, it is still controversial whether intravitreal aflibercept injection can provide better vision restoration compared with vitrectomy with panretinal photocoagulation (PRP) for proliferative diabetic retinopathy (PDR) patients. Given that there is no high-quality meta-analysis or review to incorporate existing evidence, the purpose of this study is to systematically review the level I evidence in the literature to ascertain whether intravitreal aflibercept injection can provide better vision restoration compared with vitrectomy with PRP for PDR patients.

METHODS

The systematic literature review is structured to adhere to PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-analyses), which include requirements deemed essential for the transparent reporting of results. A systematic search will be performed in Web of Science, Embase, Scopus, Science Direct, Cochrane Library up to and inclusive of March 19, 2021. The method of data extraction will follow the approach outlined by the Cochrane Handbook for Systematic Reviews of Interventions. The primary outcome is change in best-corrected visual acuity. The secondary outcomes are change in area of neovascularization and change in area of retinal nonperfusion. Where disagreement occurs, this will be resolved through discussion. All outcomes are pooled on random-effect model. A P value of < .05 is considered to be statistically significant.

RESULTS

The results of our review will be reported strictly following the PRISMA criteria.

CONCLUSIONS

The hypothesis of the study was that visual acuity recovery would be faster with vitrectomy because the blood is mechanically cleared during surgery.

REGISTRATION NUMBER

10.17605/OSF.IO/NCAXW.

Pre-Emptive Topical Ketorolac Tromethamine 0.5% for Panretinal Photocoagulation

Purpose: To evaluate the efficacy of topical ketorolac tromethamine 0.5% given pre-emptively a day before, for alleviating pain in patients undergoing panretinal photocoagulation (PRP) treatment. Methods: A controlled single-blinded study was conducted on 33 patients with diabetic retinopathy (DR; severe nonproliferative DR, proliferative DR, or advanced diabetic eye disease) who required PRP treatment in both eyes simultaneously. Each eye of the patients was randomly assigned for ketorolac tromethamine 0.5% eyedrop or placebo. Both eyedrop bottles were randomly labeled. Eyedrops were self-administered by the patients, 4 times a day before the procedure (at 6 am, 12 noon, 6 pm, and 12 midnight) and every 15 min for 1 h (4 times) before the laser. Each patient was subjected to PRP using a Visulas 532s Zeiss device set to spot size 200 μm, time 0.10 s, and ∼600 burns in each eye. The pain score was evaluated immediately after treatment in each eye independently with Scott's visual analog scale (VAS) and the McGill Pain Questionnaire (MPQ). Results: VAS pain score in ketorolac-treated eyes (median 3.0, interquatile range [IQR] ±2.5) was lower than in placebo-treated eyes (median 5.0, IQR ±3.0). Total Pain Rate Index score from MPQ was lower in ketorolac-treated eyes (median 3.0, IQR ±3.0) than in placebo-treated eyes (median 3.0, IQR ±2.5). Both pain score differences are statistically significant with P ˂ 0.05. Conclusion: Topical ketorolac tromethamine 0.5% given pre-emptively a day before is effective in alleviating pain in patients undergoing PRP treatment.

Efficacy and safety of qiming granule combined with laser in the treatment of diabetic retinopathy: A protocol of randomized controlled trial

BACKGROUND

Diabetic retinopathy is not only the most common complication of diabetes, but also 1 of the main causes of blindness, which seriously affects the physical and mental health of patients. Panretinal photocoagulation is a common method for the treatment of diabetic retinopathy, but it has some defects. Qiming granule has advantages in the treatment of diabetic retinopathy, but there is a lack of standard clinical research to verify it. Therefore, the purpose of this randomized controlled trial is to evaluate the efficacy and safety of qiming granule combined with laser in the treatment of diabetic retinopathy.

METHODS

This is a prospective randomized controlled trial to study the efficacy and safety of Qiming granule combined with laser in the treatment of diabetic retinopathy. Approved by the Clinical Research Society of our hospital. The patients are randomly divided into a treatment group (Qiming granule combined with laser treatment group) or control group (simple laser treatment group). The patients are followed up for 12 months after 6 months of treatment. Observation indexes include total effective rate, corrected visual acuity, macular fovea thickness, adverse reactions and so on. Data are analyzed using the statistical software package SPSS version 18.0 (Chicago, IL).

DISCUSSION

This study will evaluate the clinical efficacy and safety of qiming granule combined with laser in the treatment of diabetic retinopathy. The experimental results of this study will provide a reliable reference basis for clinical use of qiming granule combined with laser in the treatment of diabetic retinopathy.

TRIAL REGISTRATION

OSF Registration number: DOI 10.17605/OSF.IO/ZEQPB.

Comparison of Pain Scores Among Patients Undergoing Conventional and Novel Panretinal Photocoagulation for Diabetic Retinopathy: A Systematic Review

PURPOSE

To summarize key findings from a systematic review focusing on pain as an adverse outcome of panretinal photocoagulation (PRP) among patients with diabetic retinopathy.

DESIGN

Systematic review.

METHODS

We systematically searched articles in major databases from July to September 2020. Studies that compared pain outcomes of PRP among diabetic patients who underwent conventional single-spot laser (SSL), conventional multi-spot laser (MSL), and/or novel navigated laser (NNL) were included. The Cochrane RoB 2 tool and ROBINS-I tool were used to evaluate the risk of bias of the included randomized controlled trials (RCTs) and controlled clinical trials (CCTs), respectively.

RESULTS

We included 13 RCTs and 4 CCTs. Thirteen studies were included for Comparison 1 (Conventional SSL versus Conventional MSL), 3 studies were included for Comparison 2 (NNL versus Conventional MSL), and 3 studies were included for Comparison 3 (NNL versus Conventional SSL). A total of 783 patients and 1961 eyes were included in this review. The review showed that NNL yielded the lowest pain scores, followed by conventional MSL, then by conventional SSL.

CONCLUSION

This review summarizes findings of multiple studies that reported pain as an adverse outcome of PRP among patients with advanced diabetic retinopathy. Data from RCTs with mostly some concerns for bias (RoB 2 tool) and CCTs with mostly moderate risk of bias (ROBINS-I tool) show benefit of using MSL over SSL, and NNL over conventional systems for PRP in diabetic retinopathy, considering pain as the primary outcome.

Exposure of Contralateral Eyes to Laser Radiation during Retinal Photocoagulation

Purpose/Aim: To investigate the risk of laser damage to the unprotected fellow eye of patients undergoing laser retinal photocoagulation with 532 nm diode pumped solid-state laser.Materials and Methods: A mannequin head was fitted with a Vega laser energy meter and PD10 photodiode laser measurement sensor. Lowest measurable energy for this sensor is 2 nJ at 900 nm. Simulated retinal laser treatments were performed on a model eye placed in one of the sockets of the mannequin head, while the laser sensor was placed in the opposite socket. Four simulated sessions of retinal photocoagulation were performed utilizing both slit lamp and indirect laser delivery systems. Each consisted of 10 applications of the laser directly into the model eye and 10 applications near but not directly into the sensor, utilizing various treatment settings.Results: No laser exposure was detected in the model eye during simulated retinal photocoagulation sessions aimed directly into the treatment eye. When the laser application was aimed near the sensor, no laser exposure was detected at the standard setting, however, in all sessions conducted at the higher laser power setting, the mean exposure detected was <6 µJConclusions: Laser exposure in the unprotected contralateral eye of patients undergoing retinal laser treatment with the PASCAL laser machine under standard PRP settings was found to be miniscule. However, we still recommend laser safety eyewear for the untreated eye to provide protection in the event of direct accidental laser exposure from surgeon error or laser malfunction, in accordance with the most current laser safety guidelines.

Changes of visual fields in treatment of proliferative diabetic retinopathy: a systematic review

The aim of this systematic review was to compare certain side-effects [visual fields (VF), dark adaptation, colour vision (CV) and contrast sensitivity (CS)] of conventional panretinal photocoagulation (PRP) with those of other treatments in proliferative diabetic retinopathy (PDR). A systematic literature search was conducted on 30 November 2018 in PubMed and Embase. The search comprised the keywords 'proliferative diabetic retinopathy', 'laser', 'treatment' and 'anti-vegf'. We included prospective studies and randomized controlled trials that investigated certain side-effects (VF, dark adaptation, CV, CS) in treatment of PDR (primary outcome). In total, 1867 articles were screened, and 10 studies were included (2176 eyes of 2086 patients examined in the VF studies and 1360 eyes of 1360 patients examined in the CV and CS studies). Visual fields (VF) were investigated in 10 studies, CV in one study and CS in one study. Treatment modalities included conventional PRP, other modalities of laser treatment and vascular endothelial growth factor (VEGF) inhibitors. Four studies demonstrated a worse VF impact of PRP than VEGF inhibitors. Seven studies reported of an overall worsening in VF after laser with no differences between different laser approaches. No differences were found in CV or CS. Overall, we found a trend, confirmed in four large studies, towards VEGF inhibitors causing less harm to VF compared to conventional PRP. Whilst VF was generally depressed after laser, it did not differ between different treatment approaches. Furthermore, it was not possible to make certain conclusions of CV or CS, with only one study in each field.

Effect of Intravitreal Bevacizumab Injection before Panretinal Photocoagulation on the Prevention of Macular Edema Aggravation in Proliferative Diabetic Retinopathy

Objective: To investigate the effects of intravitreal bevacizumab (IVB) injection before PRP on the prevention of macular edema (ME) in patients with PDR. Methods: This retrospective observational study included patients diagnosed with PDR treated by PRP with (combination group) or without (PRP alone group) preoperative IVB injection (1.25 mg/0.05 mL). The primary outcome measure was the change in the central macular thickness (CMT), while the secondary outcome measure was the change in visual acuity. Measurements were made before and at one, two, and three months after treatment. Results: In the PRP alone group, the mean baseline CMT of 277.8 μm increased to 290.4 μm at one month (p = 0.201) and 308.8 μm at two months (p = 0.002), followed by a decrease to 271.2 μm at three months (p = 0.437). In the combination group, the values at baseline and one, two, and three months after PRP were 322.9 μm, 295.4 μm (p = 0.002), 330.1 μm (p = 0.906), and 274.5 μm (p = 0.030), respectively. Visual acuity changes were comparable between the two groups at all time points. Conclusion: IVB injection before PRP leads to decreased CMT in comparison to CMT in patients with PRP alone.

Macular pigment optical density after panretinal photocoagulation

CLINICAL RELEVANCE

Panretinal photocoagulation, an important treatment method in diabetic retinopathy, can affect macular pigment optical density, which has protective and antioxidant properties. As a result of this effect, the retina may become more sensitive to high-energy visible light.

BACKGROUND

The current study assesses the effect of panretinal photocoagulation treatment on macular pigment optical density, which has essential functions for the retina.

METHODS

In this prospective clinical study, the colour perimetry method was used to measure macular pigment optical density. Thirty-six eyes of 36 participants with severe non-proliferative diabetic retinopathy without macular involvement were included in the study. Conventional panretinal photocoagulation treatments were applied at baseline, one month, two months, and at three months to the participants who clinically required this treatment. Macular pigment optical density and retinal thickness measurements were performed at baseline, months one, two, three and six.

RESULTS

The mean macular pigment optical density reduction in the fovea over the six-months was 0.02 ± 0.02 logarithmic units (p < 0.001). Similarly, the pericentral areas declined by 0.04 ± 0.03 logarithmic units (p < 0.001). Mean central macular thickness and foveal thickness increased by 5.03 ± 5.02 μm and 2.78 (interquartile range 2-4) μm, respectively. In this study, correlation analysis shows that the laser energy applied was significantly and strongly correlated with reductions in macular pigment optical density (for the fovea and pericentral area respectively: r = -0.855, p < 0.001; r = -0.895, p < 0.001). Further, there were significant and strong correlations between the applied laser energy, and central macular thickness and fovea thickness (r = 0.751, p < 0.001; ρ = 0.718, p < 0.001, respectively).

CONCLUSION

Panretinal photocoagulation may potentially cause a decrease in macular pigment density in proportion to the laser energy applied.

Anti-Vascular Endothelial Growth Factor Therapy as an Alternative or Adjunct to Pan-Retinal Photocoagulation in Treating Proliferative Diabetic Retinopathy: Meta-Analysis of Randomized Trials

Aim

To compare anti-vascular growth factor (anti-VEGF) pharmacotherapy with pan-retinal photocoagulation (PRP) for proliferative diabetic retinopathy (PDR).

Method

PubMed, Embase, Medline, the ClinicalTrials.gov and the Cochrane Central Register of Controlled Trials were reviewed systemically. Randomized controlled trials (RCT) on anti-VEGF therapy versus PRP or anti-VEGF agent combined with PRP versus PRP for PDR are eligible to be included. Outcome measures were regression and recurrence of neovascularization, change in best corrected vision acuity, development of vitreous hemorrhage, and need for vitrectomy. A meta-analysis was conducted using RevMan (Cochrane Collaboration, Oxford, United Kingdom).

Results

Twelve RCTs with a total of 1026 eyes were identified. The meta-analysis results showed that regression of neovascularization did not vary significantly among different treatment regimens (P=0.06), whereas the recurrence of new vessels was significantly lower in PRP monotherapy (P < 0.00001). The best corrected visual acuity was significantly improved with anti-VEGF monotherapy or in the combined group than in the PRP groups (P < 0.00001, P=0.04, respectively). Odds ratio for post-treatment vitreous hemorrhage and vitrectomy rate between anti-VEGF therapy and PRP were 0.65 (95% confidence interval, 0.45–0.95; P = 0.03), and 0.24 (95% confidence interval, 0.12–0.48; P < 0.0001).

Conclusion

Our meta-analysis indicates that anti-VEGF pharmacotherapy is associated with superior visual acuity outcomes and less PDR-related complications. However, there is insufficient evidence to suggest anti-VEGF therapy as an alternative to PRP.

Effects of intravitreal conbercept before panretinal photocoagulation on lipid exudates in diabetic macular documented by optical coherence tomography

AIM

To evaluate the effects of intravitreal conbercept (IVC) as adjunctive treatments before panretinal photocoagulation (PRP) to decrease hyperreflective dots (HRDs) in Chinese proliferative diabetic retinopathy (PDR) patients.

METHODS

Fifty-nine enrolled patients were categorized into 2 groups: single dose IVC (0.5 mg/0.05 mL) 1wk before PRP (Plus group) or PRP only (PRP group). Six months later, we measured the best corrected visual acuity (BCVA), central macula thickness (CMT) by optical coherence tomography and counted the number of HRDs in different retina layers.

RESULTS

The average CMT significantly decreased in Plus group but increased in PRP group. The average BCVA in the Plus group was also significantly better than that in the PRP group. Total HRDs decreased in the Plus group but increased in PRP group significantly. IVC pre-treatment has beneficial effects on reducing HRDs forming in the inner retina layer while the PRP alone increased the HRDs in the outer retina layer.

CONCLUSION

IVC is a promising adjunctive treatment to PRP in the treatment of PDR. Single dose IVC one week before PRP is suggested to improve retina blood-retina barrier, decrease lipid exudate and inhibit HRDs development in PDR.

Electroretinogram Changes Following Sequential Panretinal Photocoagulation for Proliferative Diabetic Retinopathy

Purpose

To evaluate changes in electroretinogram (ERG) response over the course of multiple sessions of panretinal photocoagulation (PRP) in patients with proliferative diabetic retinopathy (PRP).

Methods

A prospective cohort study of 11 patients with PDR who required PRP was conducted. PRP was completed over three sessions. Each patient had five ERGs done: baseline, 1 week after each PRP session, and 6 weeks after the last session of PRP. Dark-adapted 0.01 ERG, Dark-adapted 3 ERG, Dark-adapted 10 ERG, Light- adapted 3 ERG, and Light-adapted 30 Hz flicker ERG were done. The mean change in a- and b-wave amplitudes as well as implicit times compared to baseline was analyzed.

Results

A significant reduction in peak amplitudes of both a- and b-waves and delay in latencies were observed in all responses (p<0.05). The absolute amplitude reduction and delay in latency were higher for scotopic b-waves (p<0.05). The root mean square (RMS) of Dark-adapted 10.0 ERG (p<0.05) and total mean amplitude changes of a- and b-waves (p<0.001) were reduced after each laser session; however, the magnitude of change was not different between the first, second, or third sessions of PRP, and each session showed a similar deterioration rate of ERG parameters comparing to each other (p=0.4 for RMS and p=0.2 for total mean amplitude changes). In addition, the results indicated recovery of the amplitude and latency of ERG waves after 6 weeks from the final treatment (p<0.001) although not to baseline levels.

Conclusion

ERG findings following PRP show reduced retinal function after each session which partially recovers by 6 weeks after the completion of therapy. Clinicians should be mindful of these changes when planning the treatment course for patients with PDR.

American Society of Retina Specialists Clinical Practice Guidelines on the Management of Nonproliferative and Proliferative Diabetic Retinopathy without Diabetic Macular Edema

Purpose

Nonproliferative (NPDR) and proliferative diabetic retinopathy (PDR) without diabetic macular edema (DME) affect millions of individuals living with diabetes throughout the world. There is increasing data on various management strategies for such patients, but there is limited consensus on how the data should be adopted into clinical practice.

Methods

This literature review and editorial presents and synthesizes the current evidence for various management paradigms for NPDR and PDR without DME.

Results

Retina specialists are an integral member of the diabetes management team, and should encourage patients on the importance of glycemic and cardiovascular optimization for both systemic and retinopathy risk factor reduction. The diabetic retinopathy severity scale (DRSS) is now an approvable endpoint for clinical trials in the United States, therefore becoming more clinically relevant. For PDR without DME, the Diabetic Retinopathy Study (DRS) and the Early Treatment Diabetic Retinopathy Study (ETDRS) established the standard of care with panretinal photocoagulation (PRP). Laser parameters have since evolved to include less intense and earlier intervention. Studies have recently demonstrated that anti-vascular endothelial growth factor (VEGF) treatment of PDR is effective at regressing neovascularization and improving DRSS levels in many patients. Further evidence is required to determine optimal treatment frequency, duration, and retreatment criteria, in the real world. There are concerns for adverse events in patients being lost to follow up during anti-VEGF treatment. For NPDR without DME, the standard of care has been a wait-and-watch approach. Data within the DRS and the ETDRS suggest that PRP for severe NPDR can be an option for select patients as well. Multiple clinical trials have now demonstrated that anti-VEGF treatment can improve the DRSS score in NPDR. Further studies are required to assess whether this positively affects long-term visual outcomes, and whether the benefits outweigh the risks in the real world for routine use.

Conclusions

There is cumulative evidence demonstrating the efficacy of various treatment options for NPDR and PDR without DME. Currently, patients would most likely benefit from thoughtful management strategies that are tailored to the individual patient.

Treated PDR Reveals Age-Appropriate Vision Deterioration But Distorted Retinal Organization

Purpose

We determined the progression of visual function, macular structure, and quality of life in patients with regressed proliferative diabetic retinopathy (PDR) after panretinal photocoagulation (PRP).

Methods

In this prospective study, 22 patients who underwent PRP for PDR and 11 age-matched control participants underwent examinations at baseline and after 5 years. Visual acuity, contrast sensitivity, reading acuity, frequency doubling perimetry, Humphrey field analyzer, and dark adaptation were measured. The Low Luminance Questionnaire and National Eye Institute Vision Function Questionnaire-25 were administered. Macular spectral-domain optical coherence tomography was taken.

Results

After 5 years, patients who had previously undergone PRP for PDR (18.4 ± 7.9 years previously) showed significant deterioration in contrast sensitivity, reading acuity, frequency doubling perimetry 24-2 pattern standard deviation, and Humphrey field analyzer 10-2 foveal sensitivity, which were equivalent to age-related decreases in control participants. They revealed no further impairment in vision-related activities on questionnaires. In contrast with controls, their maculas showed pathologic disorganization of the retinal layers, especially the nerve fiber layer, which were thicker and constituted a greater proportion of the overall retinal thickness than the norm and associated with impaired vision.

Conclusions

Patients with treated PDR had age-related decreases in vision, but stable quality of life. Prior injuries from the diabetes and, possibly, laser treatment led to substantial disruption in the retinal structure, which may explain the loss of vision.

Translational Relevance

Despite PRP treatment, patients with regressed PDR had pathologic progression of the nerve fiber layer; further investigation may identify a new therapeutic target to reverse the visual deficits.

A meta-analysis to study the effect of pan retinal photocoagulation on retinal nerve fiber layer thickness in diabetic retinopathy patients

Background. Diabetic retinopathy is a microvascular disease, it is associated with changes in peripapillary retinal nerve fiber layer thickness, these changes being more pronounced in PDR (Proliferative diabetic retinopathy) patients undergoing laser photocoagulation. Objective. To assess changes in peripapillary retinal nerve fiber layer thickness in proliferative diabetic retinopathy patients using optical coherence tomogram (OCT). Methods. The database search was conducted in June 2018 and continued until October 2018. The search engines used included Pubmed, Medline, OVID and Google Scholar. A meta-analysis of weighted mean difference and standard deviation was conducted. Results. A total of 10 studies containing 377 eyes of PDR patients were selected. The analysis of the included studies revealed no significant effect of PRP on average retinal nerve fiber layer thickness (0.249, 95% CI: -0.985 to 1.483) using OCT. Conclusion. Hence, to conclude, our meta-analysis revealed that there was no significant effect of PRP on RNFL thickness and the impact of PRP could vary. Measurement of peripapillary RNFL thickness may yield erroneous and unpredictable results in this subgroup of patients, further confounding the evaluation of nerve fiber layer damage and its progression.

Longitudinal analysis of subfoveal choroidal thickness after panretinal laser photocoagulation in diabetic retinopathy using swept-source optical coherence tomography

Purpose: To describe the central three-dimensional (3D) thickness profile of the macula (CMT) and the subfoveal choroidal region (SFCT) in diabetic retinopathy (DR) following panretinal laser photocoagulation (PRP) using swept-source optical coherence tomography (SS-OCT). Methods: A prospective observational study including 17 eyes with proliferative DR (PDR) and 27 eyes with severe nonproliferative DR (sNPDR)] for whom PRP was done. All subjects received SS-OCT imaging before and 3 months after PRP (POM#3). SFCT and CMT changes were analysed at both visits. Intraclass Correlation Coefficients (ICC) and Coefficients of Variation (COV) were used to test the accuracy of thickness data. Results: SFCT has thinned from 233 ± 54 µm before PRP treatment to 216 ± 51 µm 3 months later (p < 0.001). Likewise, CMT declined at POM#3 as compared to pre-PRP status (p<0.001). SFCT was thinner in PDR before and at POM#3 (p<0.05) than sNPDR; whereas, no significant difference was observed in CMT between both groups in the two visits. No significant changes were found between groups in SFCT and CMT at POM#3. Regarding reliability, ICCSFCT=0.98 and ICCCMT=0.99. The COVs for CMT and SFCT were 5.03% and 5.91%, respectively. Conclusion: The mean SFCT and CMT decreased 3 months after PRP. We also reported reliability of SFCT measurements in DR using SS-OCT. Abbreviations: SS = Swept-Source, TD = time domain, SD = spectral domain, FD = Fourier-domain, 3D = three-dimensional, 2D = two-dimensional.

Vascular endothelial growth factor inhibition and proliferative diabetic retinopathy, a changing treatment paradigm?

Prior to the development of panretinal photocoagulation (PRP) in the 1970s, proliferative diabetic retinopathy (PDR) was the most common cause of blindness in diabetic patients. The diabetic retinopathy study demonstrated that PRP could decrease severe visual loss from PDR by 50%. Since then and for the past four decades, PRP has been the treatment of choice for eyes with PDR. In the past decade, vascular endothelial growth factor (VEGF) inhibition has become the treatment of choice for diabetic macular edema (DME). When treated intensively with anti-VEGF drugs, about one-third of eyes with DME experience an improvement in their diabetic retinopathy severity scale. Randomized clinical trials comparing ranibizumab to PRP and aflibercept to PRP have shown that VEGF inhibitors cause regression of intraocular neovascularization but need to be given on a fairly regular basis. Despite these promising results, concerns about treatment adherence have surfaced. Patients with PDR that are treated solely with anti-VEGF drugs and somehow interrupt their treatment are at a high risk of developing irreversible blindness. Combination treatment of PRP plus an anti-VEGF drug may be the treatment of choice for PDR.

Reading deficits in diabetic patients treated with panretinal photocoagulation and good visual acuity

PURPOSE

Patients with proliferative diabetic retinopathy (PDR) treated with panretinal photocoagulation (PRP) can have abnormal visual functioning that may be missed by Snellen visual acuity alone. We investigated reading deficits in patients treated with PRP for PDR using the Minnesota reading (MNREAD) test.

METHODS

Thirty patients treated with PRP and 15 controls underwent best-corrected visual acuity (BCVA), the MNREAD, frequency doubling perimetry (FDP), and fundus photography. Panretinal photocoagulation (PRP)-treated subjects were compared to controls on MNREAD results by two-sample t-tests and Wilcoxon tests and Pearson correlations were used to assess the association between performance on MNREAD and other central visual function tests within PRP subjects.

RESULTS

Panretinal photocoagulation (PRP)-treated patients had reduced MNREAD acuity (p < 0.0001) and increased critical print size (p = 0.01) compared to controls but not a significantly reduced maximum reading speed (p = 0.06). Logmar MNREAD acuity was strongly positive correlated with logMAR BCVA (r = 0.58, p = 0.0098) and strongly negatively correlated with FDP foveal threshold (r = -0.63, p = 0.0030). Maximum reading speed was positively correlated with FDP foveal threshold (r = 0.57, p = 0.0143) and FDP mean deviation (r = 0.51, p = 0.0432). Visual acuity did not correlate with the sensitivities on the FDP.

CONCLUSION

The MNREAD test reveals that PRP reduces reading ability and other aspects of macular function, and thus provides new understanding of how vision-related quality of life is impaired. These findings may lead to improved means to evaluate and enhance vision following treatment for PDR.

Long term effect of panretinal photocoagulation on retinal nerve fiber layer parameters in patients with proliferative diabetic retinopathy

PURPOSE:

This study aimed to evaluate the long-term effect of panretinal photocoagulation (PRP) on the retinal nerve fiber layer (RNFL) in patients with proliferative diabetic retinopathy (PDR).

METHODS:

This was a prospective longitudinal cohort study examining 42 eyes of 42 patients with PDR undergoing PRP. Peripapillary RNFL thickness (RNFLT) was measured using spectral-domain optical coherence tomography at baseline, 1 year, and 3 years following PRP.

RESULTS:

The mean “average RNFLT” was 89.88 ± 14.26 μm at baseline, 85.75 ± 11.36 μm at 1-year follow-up, and 83.33 ± 11.96 μm at 3-year follow-up. There was a statistically significant difference in the average RNFL thickness at baseline and 1 year and 3 years after PRP. At 1-year follow-up, superior, inferior, and nasal RNFL measurements reduced significantly from baseline (P < 0.01). The reduction in RNFL remained statistically significant for superior and inferior quadrants 3 years after PRP.

CONCLUSION:

PRP causes a reduction in RNFL thickness until 3 years after the procedure. Caution should be exercised while interpreting peripapillary RNFL thickness scans in patients who have undergone PRP for diabetic retinopathy.

Central retinal thickness following panretinal photocoagulation using a multispot semi-automated pattern-scanning laser to treat ischaemic diabetic retinopathy: Treatment in one session compared with four monthly sessions

PURPOSE

To compare central retinal thickness (CRT) after panretinal photocoagulation (PRP) with a multispot semi-automated PAttern-SCAnning Laser (PASCAL) in one session (SS-PRP) versus four monthly sessions (MS-PRP) in diabetic retinopathy.

METHODS

Multicentre, prospective, randomized, single-blinded, controlled trial evaluating the noninferiority of SS-PRP versus MS-PRP for CRT measured with macular spectral-domain optical coherence tomography (SD-OCT), with a 9-month follow-up in patients presenting severe nonproliferative diabetic retinopathy (DR) or mild proliferative DR without macular oedema (ME) at baseline.

RESULTS

Ninety-seven eyes of 97 participants with a mean age of 57.0 ± 14.2 years were included. The mean change of CRT from baseline to 9 months was not statistically different in SS-PRP or in MS-PRP: +16.9 ± 28.3 μm versus +24.7 ± 31.8 μm, respectively (p = 0.224). The variation in mean best-corrected visual acuity (BCVA) from baseline to 9 months was similar in both groups: -1.1 ± 6.5 letters versus -0.6 ± 6.2 letters (p = 0.684). The number of patients with stabilization of DR was not statistically different between the two groups. No severe complication was recorded in either group.

CONCLUSION

This study showed the noninferiority of PRP performed in one session versus four monthly sessions with a PASCAL concerning central retinal thickness for treating mild proliferative or severe nonproliferative DR without ME at baseline.

Intravitreal Ranibizumab With Panretinal Photocoagulation Followed by Trabeculectomy Versus Visco-Trabeculotomy in Management of Neovascular Glaucoma

PURPOSE

The aim of the current study was to compare visco-trabeculotomy (VT) with standard trabeculectomy with mitomycin C (Trab-MMC) in the treatment of quiescent neovascular glaucoma (NVG).

METHODS

The study was conducted on 51 eyes of 51 patients presenting with NVG and treated at an Ophthalmic Center in Egypt between March 2014 and April 2017. All study eyes were subjected to a standard protocol of intravitreal injection of ranibizumab followed by panretinal photocoagulation. Eyes were then randomized to either VT or Trab-MMC. Study eyes were followed up for at least 18 months. Success was defined as an intraocular pressure of ≤21 mm Hg and without vision-threatening complications. Complications were noted.

RESULTS

The mean ± SD (range, median) age of the study patients was 54.1 ± 6.4 (40-67, 54.5) and 52.4 ± 8.8 (38-66, 53) years in the VT (26 eyes) and Trab-MMC (25 eyes) groups, respectively (P = 0.45). The mean ± SD (range, median) intraocular pressure (IOP) of the study eyes was 45.19 ± 2.97 (39-52, 45.5) and 45.64 ± 3.56 (3-53, 45) mm Hg on maximal medical therapy in the VT and Trab-MMC groups, respectively (P = 0.61). At 18 months' follow-up, the mean ± SD (range, median) IOP of the study eyes was 18.19 ± 2.0 (16-23, 17) and 19.92 ± 2.6 (18-26, 19) mm Hg in the VT and Trab-MMC groups, respectively (P = 0.004). There was no difference in postoperative antiglaucoma medication between the 2 groups (P = 0.62). Complications included hyphema and Descemet split in the VT group and an IOP spike in the Trab-MMC group. Success rates were 84.6% and 80% in the VT and Trab-MMC groups, respectively (P = 0.726).

CONCLUSIONS

Both VT and Trab-MMC groups are effective in reducing the IOP in cases of NVG after control of neovascularization with anti-vascular endothelial growth factor and pan retinal photocoagulation.

Evaluation of blood flow on optic nerve head after pattern scan and conventional laser panretinal photocoagulation

To evaluate the changes in the blood flow on retina and the optic nerve head (ONH) after conventional laser treatment and to compare it to that after patterned scanning laser (PASCAL) treatment in patients with severe nonproliferative diabetic retinopathy (S-NPDR).In this prospective, cross-sectional study, the blood flow on retina and the ONH was assessed by laser speckle flowgraphy using the mean blur rate (MBR) in 39 eyes with S-NPDR before, 1, 4, 8, 12 weeks after panretinal photocoagulation (PRP). Of 39 eyes, 17eyes with 17 patients treated by conventional laser and 22 eyes with 22 patients treated by PASCAL.The mean age was 55.5 ± 11.5 years in the conventional laser group, 55.6 ± 11.8 years in the PASCAL group. The MBR-vessel, which can be dominantly expressed as retinal blood flow, was significantly reduced after PRP treated by conventional laser (P < .001), but did not change after PRP treated by PASCAL. The ratio of MBR-vessel to the baseline was significantly lower in the conventional laser group only at Week 1 (P = .045). The MBR-tissue, which can be dominantly expressed as the ONH blood flow, did not significantly change after PRP in the both group. The multiple stepwise regression analysis revealed that the laser burns was an independent factor significantly correlated with the ratio of MBR-vessel at Week 1 to the baseline (β = -0.550, P = .012).The retinal blood flow was significantly reduced during the 12 weeks only after completion of PRP by conventional laser treatment. Our results indicate that short pulse on PRP treatment performed by the PASCAL would not significantly reduce the retinal blood flow.