Altered oxylipin levels in human vitreous indicate imbalance in pro-/anti-inflammatory homeostasis in proliferative diabetic retinopathy.

Proliferative diabetic retinopathy (PDR) is an advanced stage of diabetic retinopathy (DR), characterized by retinal neovascularization. It is a progressive fundus disease and a severe complication of diabetes that causes vision impairment. Hyperglycemia-induced persistent low-grade inflammation is a crucial factor underlying the pathogenesis of DR-associated damage and contributing to the progression of PDR. Highly enriched polyunsaturated fatty acids (PUFAs) in the retina are precursors to oxidized metabolites, namely, oxylipins, which exert pro-inflammatory or anti-inflammatory (resolving) effects under different pathological conditions and have been implicated in diabetes. To evaluate differences in oxylipin levels in the vitreous obtained from PDR and non-diabetic subjects, we performed a targeted assessment of oxylipins. A total of 41 patients with PDR and 22 non-diabetic control subjects were enrolled in this study. Vitreous humor obtained during routinely scheduled vitrectomy underwent a targeted but unbiased screening for oxylipins using mass spectrometry-based lipidomics. We found 21 oxylipins showing statistically significant differences in their levels between PDR and non-diabetic subjects (p < 0.05). Lipoxygenase (LOX)- and cytochrome P450 (CYP)- derived oxylipins were the most affected, while cyclooxygenase (COX) oxylipins were affected to a lesser extent. When categorized by their precursor PUFAs, ±19,20-EpDPE, a CYP product of docosahexaenoic acid (DHA) and 12S-HETE, a LOX product of arachidonic acid (ARA), were increased by the largest magnitude. Moreover, of these 21 oxylipins, 7 were considered as potential biomarkers for discriminating PDR patients from the non-diabetic controls. Our results indicate that altered oxylipin levels in the vitreous implicate an underlying imbalanced inflammation-resolution homeostasis in PDR.

Early pars plana vitrectomy for proliferative diabetic retinopathy: update and review of current literature.

PURPOSE OF REVIEW: Diabetic retinopathy (DR) is one of the leading causes of preventable vision loss in the world and its prevalence continues to increase worldwide. One of the ultimate and visually impairing complications of DR is proliferative diabetic retinopathy (PDR) and subsequent tractional retinal detachment. Treatment modalities, surgical techniques, and a better understanding of the pathophysiology of DR and PDR continue to change the way we approach the disease. The goal of this review is to provide an update on recent treatment modalities and outcomes of proliferative diabetic retinopathy and its complications including tractional retinal detachment. RECENT FINDINGS: Panretinal photocoagulation (PRP), anti-vascular endothelial growth factor (anti-VEGF), and pars plana vitrectomy are the mainstay of PDR treatment. However, PRP and anti-VEGF are associated with significant treatment burden and multiple subsequent treatments. Early vitrectomy is associated with vision preservation, less treatment burden, and less subsequent treatments than therapy with PRP and anti-VEGF. SUMMARY: Concerning costs, high rates of noncompliance in the diabetic population and significant rates of subsequent treatments with initial PRP and anti-VEGF, early vitrectomy for diabetic retinopathy in patients at risk of PDR is a cost-effective long-term stabilizing treatment for diabetics with advanced disease.

NOVEL THREE TYPES OF NEOVASCULARIZATION ELSEWHERE DETERMINE THE DIFFERENTIAL CLINICAL FEATURES OF PROLIFERATIVE DIABETIC RETINOPATHY.

PURPOSE: To explore the pathological features and clinical significance of three types of neovascularization elsewhere (NVE) in proliferative diabetic retinopathy. METHODS: Neovascularization elsewhere was classified based on the origins and morphologic features using fluorescein angiography and angiographic and structural optical coherence tomography. The topographical distribution, vitreoretinal interface, and responsiveness to panretinal photocoagulation were compared among three types of NVE. RESULTS: One hundred and twenty-seven NVEs were classified into three types. Type 1 NVE was concentrated along or adjacent to vascular arcades; Type 2 was distributed more peripherally than were Types 1 and 3 NVE. The arch bridge-like vitreoretinal interface accounted for 79% of Type 1 NVE. The flat and flat-forward vitreoretinal interface accounted for 95% and 100% in Type 2 and Type 3 NVE, respectively. At 3 months after panretinal photocoagulation, the regression rates for Types 1, 2, and 3 NVE were 82%, 100%, and 80%, respectively. Type 2 NVE showed best regression rate after panretinal photocoagulation (both P < 0.01). CONCLUSION: Three types of NVE determine the distinctly topographical distributions, vitreoretinal interface features, and differential responsiveness to panretinal photocoagulation treatment. This new concept may have important clinical implications in assessing the treatment and prognosis of proliferative diabetic retinopathy.

Observation of retinal neovascularization using optical coherence tomography angiography after panretinal photocoagulation for proliferative diabetic retinopathy.

BACKGROUND: To describe the longitudinal changes in retinal neovascularization elsewhere (NVE) as observed on optical coherence tomography angiography (OCTA) in proliferative diabetic retinopathy (PDR) treated by panretinal photocoagulation (PRP). METHODS: Each patient included in this prospective clinical study was newly diagnosed with PDR and NVE confirmed by both fundus fluorescein angiography (FFA) and OCTA. They received four sessions of PRP using a multiwavelength laser. Best-corrected visual acuity (BCVA) and OCTA images of the NVE were obtained before each PRP session and at 1 month, 3 months, and 6 months after the PRP treatment. Generalized estimating equations (GEE) was used to investigate the differences between the BCVA and NVE areas before and after PRP. RESULTS: Thirty-two eyes of 32 patients with a mean age of 50.56 ± 7.05 years were included. We found a statistically significant reduction in the NVE area at all time points compared with the baseline except at 6 months (all P < 0.05). Further analysis demonstrated no statistically significant change in the NVE area between two adjacent timepoints except from baseline to post-1st PRP (P < 0.05). BCVA at 3 months showed a statistically significant improvement compared with baseline (P < 0.05), but no significant changes in BCVA were observed during the other visits. CONCLUSIONS: We found an overall regression in the NVE area following PRP starting as early as 1 week after the 1st session and lasting up to 3 months. OCTA provides quantitative information on vascular changes and could be a practical method for the longitudinal evaluation of neovascularization.

Peripheral retinal neovascularization secondary to highly myopic superficial Retinoschisis: a case report.

BACKGROUND: Peripheral Retinal neovascularization is well-described as a complication of X-linked retinoschisis, but less often observed in myopic and primary retinoschisis. We present a case of a myopic female who developed retinal microvascular abnormalities due to retinoschisis and subsequent vitreous hemorrhage which would cause severe visual damage without timely and proper treatment. CASE PRESENTATION: A 38-year-old highly myopic Chinese female complained of blurred vision in her right eye. Her best corrected visual acuitiy was 20/20 OU, and her refraction was - 9.00S OU. Dilated fundus examination revealed mild vitreous hemorrhage and abnormal vascular network nasal to the optic disc in her right eye. Optical Coherence Tomography (OCT)- angiography (OCTA) B-Scan showed superficial retinoschisis and well-depicted abnormal retinal microvascular network in inner retinal layer. Sectoral scatter laser photocoagulation was administered. Regression of most abnormal vessels was achieved in 1 month, but the patient experienced an unexpected episode of vitreous hemorrhage 3 months after the initial treatment, which was absorbed spontaneously in 2 weeks. Supplemental laser photocoagulation was applied and regular follow-up visit was suggested. CONCLUSION: Superficial retinoschisis in pathological myopia can be a driver of retinal microvascular abnormalities, possibly neovascularization, an extremely rare but severe complication which can be vision-threatening without timely and proper intervention.

Outcomes of Eyes Lost to Follow-up with Proliferative Diabetic Retinopathy That Received Panretinal Photocoagulation versus Intravitreal Anti-Vascular Endothelial Growth Factor.

PURPOSE: To compare anatomic and functional outcomes in eyes with proliferative diabetic retinopathy (PDR) that were lost to follow-up (LTFU) for more than 6 months after treatment with either intravitreal injection (IVI) of anti-vascular endothelial growth factor (VEGF) agents or panretinal photocoagulation (PRP). DESIGN: Retrospective cohort study. PARTICIPANTS: Fifty-nine patients who were LTFU immediately after treatment for more than 6 months between September 2013 and September 2016. METHODS: Patients with eyes receiving either intravitreal anti-VEGF treatment or PRP with the next follow-up visit occurring more than 6 months after treatment were identified. Visual acuity (VA) and anatomic outcomes at the visit before being LTFU, the return visit, the 6-month visit after return, the 12-month visit after return, and the final visit were gathered and compared between the 2 treatment groups. MAIN OUTCOMES MEASURES: Visual acuity and anatomic outcomes. RESULTS: Seventy-six eyes of 59 patients were included in the study, of which 30 received IVI with anti-VEGF and 46 received PRP. In the anti-VEGF group, mean VA worsened significantly when comparing the visit before being LTFU (0.43±0.38 logarithm of the minimum angle of resolution [logMAR]) with the return visit (0.97±0.80 logMAR; P = 0.001) as well as with the final visit (0.92±0.94 logMAR; P = 0.01). In the PRP group, mean VA worsened significantly when comparing the visit before being LTFU (0.42±0.34 logMAR) with the return visit (0.62±0.64 logMAR; P = 0.03). However, no significant difference was observed at the final visit (0.46±0.47 logMAR; P = 0.38). There was a significantly greater number of eyes with tractional retinal detachment in the IVI group compared with the PRP group at the final visit (10 vs. 1, respectively; P = 0.005). There was a significantly greater incidence of neovascularization of the iris in the IVI arm compared with the PRP arm at the final visit (4 vs. 0, respectively; P = 0.02). CONCLUSIONS: Eyes with PDR that received only intravitreal anti-VEGF demonstrated worse anatomic and functional outcomes after being LTFU compared with eyes that received PRP. Given the potential sequelae of being LTFU, the choice of treatment for PDR must be considered carefully.

Peripheral Microvascular Abnormalities Detected by Wide-Field Fluorescein Angiography in Eyes with Branch Retinal Vein Occlusion.

PURPOSE: To evaluate the location of microvascular abnormalities using wide-field fluorescein angiography (WFFA) and investigate the impact on visual outcome in eyes with branch retinal vein occlusion (BRVO). METHODS: Forty eyes of 39 patients (24 males and 15 females with an average age of 71 years) were retrospectively reviewed. One patient had BRVO bilaterally. WFFA was performed in all patients to evaluate perfusion status and detect microvascular abnormalities. The WFFA images were divided into 3 zones: zone 1, posterior pole; zone 2, mid-periphery; zone 3, far periphery, in order to document the presence of microvascular abnormalities. Scatter retinal photocoagulation (PC) was performed for retinal neovascularization (NV) and/or widespread nonperfused areas (NPAs). RESULTS: The incidence of microvascular abnormalities in zone 3 was significantly (p < 0.0001) less than in zones 1 and 2. The presence of larger NPAs in zone 1, but not in zone 3, was associated with the incidence of NV and vitreous hemorrhage. The presence of peripheral lesions and the application of PC did not affect the visual outcome. CONCLUSION: The presence of peripheral abnormalities or scatter PC for NPAs did not affect the visual outcome in eyes with BRVO.

Ranibizumab Plus Panretinal Photocoagulation versus Panretinal Photocoagulation Alone for High-Risk Proliferative Diabetic Retinopathy (PROTEUS Study).

PURPOSE: Comparison of the efficacy of ranibizumab (RBZ) 0.5 mg intravitreal injections plus panretinal photocoagulation (PRP) versus PRP alone in the regression of the neovascularization (NV) area in subjects with high-risk proliferative diabetic retinopathy (HR-PDR) over a 12-month period. DESIGN: Prospective, randomized, multicenter, open-label, phase II/III study. PARTICIPANTS: Eighty-seven participants (aged ≥18 years) with type 1/2 diabetes and HR-PDR (mean age, 55.2 years; 37% were female). METHODS: Participants were randomized (1:1) to receive RBZ+PRP (n = 41) or PRP monotherapy (n = 46). The RBZ+PRP group received 3 monthly RBZ injections along with standard PRP. The PRP monotherapy group received standard PRP between day 1 and month 2; thereafter, re-treatments in both groups were at the investigators' discretion. MAIN OUTCOME MEASURES: The primary outcome was regression of NV total, on the disc (NVD) plus elsewhere (NVE), defined as any decrease in the area of NV from the baseline to month 12. Secondary outcomes included best-corrected visual acuity (BCVA) changes from baseline to month 12, time to complete NV regression, recurrence of NV, macular retinal thickness changes from baseline to month 12, need for treatment for diabetic macular edema, need for vitrectomy because of occurrence of vitreous hemorrhage, tractional retinal detachment or other complications of DR, and adverse events (AEs) related to treatments. RESULTS: Seventy-seven participants (88.5%) completed the study. Overall baseline demographics were similar for both groups, except for age. At month 12, 92.7% of participants in the RBZ+PRP group presented NV total reduction versus 70.5% of the PRP monotherapy participants (P = 0.009). The number of participants with NVD and NVE reductions was higher with RBZ+PRP (93.3% and 91.4%, respectively) versus PRP (68.8% and 73.7%, respectively), significant only for NVE (P = 0.048). Complete NV total regression was observed in 43.9% in the RBZ+PRP group versus 25.0% in the PRP monotherapy group (P = 0.066). At month 12, the mean BCVA was 75.2 letters (20/32) in the RBZ+PRP group versus 69.2 letters (20/40) in the PRP monotherapy group (P = 0.104). In the RBZ+PRP group, the mean number of PRP treatments over month 12 was 3.5±1.3, whereas in the PRP monotherapy group, it was 4.6±1.5 (P = 0.001). No deaths or unexpected AEs were reported. CONCLUSIONS: Treatment with RBZ+PRP was more effective than PRP monotherapy for NV regression in HR-PDR participants over 12 months.

Prediction of regression of retinal neovascularisation after panretinal photocoagulation for proliferative diabetic retinopathy.

PURPOSE: The purpose of this study was to evaluate the regression of neovascularization elsewhere (NVE) after panretinal photocoagulation (PRP) based on its location in relation to the internal limiting membrane (ILM). METHODS: Participants in this retrospective case series were 47 patients with active NVE within the vascular arcade. All patients were treated with PRP and followed up for at least 12 months. The time to regression of NVE based on its location relative to the ILM on spectral domain-optical coherence tomography (SD-OCT) was analyzed. RESULTS: The proportion of eyes, showing regression of NVE at the end of follow-up period was 19/25 (76 %) in the "below ILM" group and 13/22 (59 %) in the "above ILM" group. The "below ILM" group was associated with a twofold enhanced regression of NVE in comparison to the "above ILM" group (HR = 2.13, p = 0.038). CONCLUSIONS: Regression of NVE is determined by its location relative to the ILM. Patients with "below ILM" NVE were found to show a twofold increased regression rate in comparison with the "above ILM" group, while the proportion of eyes showing regression of NVE at the end of the follow-up period was significantly greater in the "below ILM" than the "above ILM" group.

CHOROIDAL THICKNESS CHANGES IN PROLIFERATIVE DIABETIC RETINOPATHY TREATED WITH PANRETINAL PHOTOCOAGULATION VERSUS PANRETINAL PHOTOCOAGULATION WITH INTRAVITREAL BEVACIZUMAB.

PURPOSE: To compare choroidal thickness (CT) and retinal thickness (RT) between eyes with proliferative diabetic retinopathy treated with panretinal photocoagulation (PRP) or PRP with intravitreal bevacizumab (PRP + IVB). METHODS: Thirty-three patients with proliferative diabetic retinopathy were randomized to have one eye treated with PRP and the other with PRP + IVB. Change in CT was compared with baseline using enhanced depth imaging-optical coherence tomography at baseline and Months 1, 3, 6, and 10 after treatment. Change in RT was similarly assessed using spectral domain optical coherence tomography. Changes in both CT and RT were assessed in all nine macular areas as defined by Early Treatment Diabetic Retinopathy Study subfields. RESULTS: The PRP + IVB group had a significant decrease in subfoveal CT at 3 and 10 months (323.9 ± 62 µm at baseline vs. 320.7 ± 64.8 µm at Month 3 [P = 0.024] and 304.7 ± 65.6 µm at Month 10 [P = 0.003]). Subfoveal CT significantly decreased at 10 months compared with baseline in the PRP group (320.8 ± 57.7 at baseline to 297 ± 66.3 µm at 10 months, P = 0.01). Subfoveal CT was not significantly different between the 2 groups at 10 months. The best-corrected visual acuity did not change after treatment in the two groups, and there was no correlation between BCVA and CT changes (r = 0.222, P = 0.37 in the PRP group and r = 0.387, P = 0.12 in the PRP + IVB group). Significant increases in RT were seen in the PRP + IVB group at 6 months and in the PRP group at Months 1, 3, 6, and 10. A correlation between changes in CT and RT was only seen in the PRP group at 10 months after treatment. CONCLUSION: Eyes with proliferative diabetic retinopathy treated with PRP + IVB and PRP both had significant reduction in CT at 10 months; however, the eyes that were also treated with IVB also underwent an earlier but transient reduction at 3 months. Patients treated with IVB underwent less increase in RT.

INTRAVITREAL CONBERCEPT (KH902) FOR SURGICAL TREATMENT OF SEVERE PROLIFERATIVE DIABETIC RETINOPATHY.

PURPOSE: To evaluate the role, safety, and effectiveness of intravitreal conbercept (KH902) injections as an adjunct to vitrectomy in the management of severe proliferative diabetic retinopathy. METHODS: A randomized controlled trial was performed on 36 eyes of 36 patients affected by vitreous hemorrhage and tractional retinal detachment, which occurred as a consequence of active proliferative diabetic retinopathy. The patients were randomly assigned to two groups. The patients in one of the groups received an intravitreal injection of conbercept in the inferior temporal sector 4 mm from the sclerocorneal limbus with a sterile technique 1 week before vitrectomy. RESULTS: In the group without conbercept, intraoperative bleeding occurred in 14 patients (77.8%), and in five of these cases, bleeding was significant. The use of endodiathermy was necessary in 8 patients (44.4%). In 3 patients (16.6%), iatrogenic retinal breaks occurred, and in 1 patient (5.5%), a relaxing retinotomy was performed. Endotamponade with silicone oil was performed in 12 patients (66.6%). In the group treated with conbercept, intraoperative bleeding occurred in 2 cases (11.1%). The use of endodiathermy was necessary in 1 patient (5.5%). No patients experienced iatrogenic breaks or relaxing retinotomy during the surgery. Endotamponade with silicone oil was performed in 2 patients (11.1%). CONCLUSION: Preoperative intravitreal injection of conbercept could reduce the chances of intraoperative bleeding, which are beneficial in the management of proliferative diabetic retinopathy.

Multimodal characterization of proliferative diabetic retinopathy reveals alterations in outer retinal function and structure.

PURPOSE: To identify changes in retinal function and structure in persons with proliferative diabetic retinopathy (PDR), including the effects of panretinal photocoagulation (PRP). DESIGN: Cross-sectional study. PARTICIPANTS: Thirty adults who underwent PRP for PDR, 15 adults with untreated PDR, and 15 age-matched controls. METHODS: Contrast sensitivity, frequency doubling perimetry (FDP), Humphrey visual fields, photostress recovery, and dark adaptation were assessed. Fundus photography and macular spectral-domain optical coherence tomography (SD OCT) were performed. To quantify retinal layer thicknesses, SD OCT scans were segmented semiautomatically. MAIN OUTCOME MEASURES: Visual function measures were compared among patients with PDR and PRP, untreated patients with PDR, and controls. Mean retinal layer thicknesses were compared between groups. Correlation analyses were performed to evaluate associations between visual function measures and retinal layer thicknesses. RESULTS: A significant reduction of FDP mean deviation (MD) was exhibited in PRP-treated patients with PDR (MD ± standard deviation, -8.20±5.76 dB; P < 0.0001) and untreated patients (-5.48±4.48 dB; P < 0.0001) relative to controls (1.07±2.50 dB). Reduced log contrast sensitivity compared with controls (1.80±0.14) also was observed in both PRP-treated patients (1.42±0.17; P < 0.0001) and untreated patients (1.56±0.20; P = 0.001) with PDR. Compared with controls, patients treated with PRP demonstrated increased photostress recovery time (151.02±104.43 vs. 70.64±47.14 seconds; P = 0.001) and dark adaptation speed (12.80±5.15 vs. 9.74±2.56 minutes; P = 0.022). Patients who underwent PRP had diffusely thickened nerve fiber layers (P = 0.024) and diffusely thinned retinal pigment epithelium (RPE) layers (P = 0.009) versus controls. Untreated patients with PDR also had diffusely thinned RPE layers (P = 0.031) compared with controls. CONCLUSIONS: Patients with untreated PDR exhibited inner retinal dysfunction, as evidenced by reduced contrast sensitivity and FDP performance, accompanied by alterations in inner and outer retinal structure. Patients who underwent PRP had more profound changes in outer retinal structure and function. Distinguishing the effects of PDR and PRP may guide the development of restorative vision therapies for patients with advanced diabetic retinopathy.

The Relationship between Medicare Payment and Service Volume for Retina Procedures from 2005 through 2009.

PURPOSE: To calculate the relationship between Medicare payment and service volume for the 3 highest-volume retina procedures: intravitreal injection (Current Procedural Terminology [CPT] code 67028), laser treatment for retinal edema (CPT code 67210), and laser treatment for proliferative retinopathy (CPT code 67228). DESIGN: Retrospective, longitudinal database study. PARTICIPANTS: One hundred percent dataset of all retina procedures performed on Medicare Part B beneficiaries within the United States from 2005 through 2009. METHODS: Fixed-effects regression model using Medicare Part B carrier data for all 50 states and the District of Columbia, controlling for time-invariant carrier-specific characteristics, national trends in service volume, Medicare beneficiary population, number of ophthalmologists, and income per capita. MAIN OUTCOME MEASURES: Medicare payment-service volume elasticities, defined as the percent change in service volume per 1% change in Medicare payment, for intravitreal injection, laser treatment for retinal edema, and laser treatment for proliferative retinopathy. RESULTS: For all 3 retina procedures, the regression coefficients representing the Medicare payment-service volume elasticity were nonsignificant: intravitreal injection elasticity, -0.75 (95% confidence interval [CI], -1.62 to 0.13; P = 0.09); laser treatment for retinal edema elasticity, 0.14 (95% CI, -0.38 to 0.65; P = 0.59); and laser treatment for proliferative retinopathy elasticity, 0.05 (95% CI, -0.26 to 0.35; P = 0.77). CONCLUSIONS: This study found no evidence suggesting that there is an association between Medicare payment and service volume for the 3 highest-volume retina procedures from 2005 through 2009.

Laser therapy for retinopathy in sickle cell disease.

BACKGROUND: Sickle cell disease includes a group of inherited haemoglobinopathies affecting multiple organs including the eyes. Some people with the disease develop ocular manifestations due to vaso-occlusion. Vision-threatening complications of sickle cell disease are mainly due to proliferative sickle retinopathy which is characterized by proliferation of new blood vessels. Laser photocoagulation is widely applicable in proliferative retinopathies such as proliferative sickle retinopathy and proliferative diabetic retinopathy. It is important to evaluate the efficacy and safety of laser photocoagulation in the treatment of proliferative sickle retinopathy to prevent sight-threatening complications. OBJECTIVES: To evaluate the effectiveness of various techniques of laser photocoagulation therapy in sickle cell disease-related retinopathy. SEARCH METHODS: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. Date of last search: 21 September 2015.We also searched the following resources (24 March 2015): Latin American and Carribean Health Science Literature Database (LILACS); WHO International Clinical Trials Registry Platforms (ICTRP); and ClinicalTrials.gov. SELECTION CRITERIA: Randomised controlled trials comparing laser photocoagulation to no treatment in children and adults. DATA COLLECTION AND ANALYSIS: Two authors independently assessed trial eligibility, the risk of bias of the included trials and extracted and analysed data. We contacted the trial authors for additional information. MAIN RESULTS: Two trials (341 eyes of 238 children and adults) were included comparing efficacy and safety of laser photocoagulation to no therapy in people with proliferative sickle retinopathy. There were 121 males and 117 females with an age range from 13 to 67 years. The laser photocoagulation technique used was different in the two trials; one single-centre trial employed sectoral scatter laser photocoagulation using an argon laser; and the second, two-centre trial, employed feeder vessel coagulation using argon laser in one centre and xenon arc in the second centre. The follow-up period ranged from a mean of 21 to 32 months in one trial and 42 to 47 months in the second. Both trials were at risk of selection bias (random sequence generation) because of the randomisation method employed for participants with bilateral disease. One study was considered to be at risk of reporting bias.Using sectoral scatter laser photocoagulation, one trial (174 eyes) reported that complete regression of proliferative sickle retinopathy was seen in 30.2% in the laser group and 22.4% in the control group (no difference between groups). The same trial reported the development of new proliferative sickle retinopathy in 34.3% of laser-treated eyes and in 41.3% of eyes given no treatment; again, there was no difference between treatment groups. The second trial, using feeder vessel coagulation, did not present full data for either treatment group for these outcomes.There was evidence from both trials (341 eyes) that laser photocoagulation using scatter laser or feeder vessel coagulation may prevent the loss of vision in eyes with proliferative sickle retinopathy (at median follow up of 21 to 47 months). Data from both trials indicated that laser treatment prevented the occurrence of vitreous haemorrhage with both argon and xenon laser; with the protective effect being greater with feeder vessel laser treatment compared to scatter photocoagulation.Regarding adverse effects, the incidence of retinal tear was minimal, with only one event reported. Combined data from both trials were available for 341 eyes; there was no difference between the laser and control arms for retinal detachment. In relation to choroidal neovascularization, treatment with xenon arc was found to be associated with a significantly higher risk, but visual loss related to this complication is uncommon with long-term follow up of three years or more.Data regarding quality of life and other adverse effects were not reported in the included trials. AUTHORS' CONCLUSIONS: Our conclusions are based on the data from two trials conducted over 20 years ago. In the absence of further evidence, laser treatment for sickle cell disease-related retinopathy should be considered as a one of therapeutic options for preventing visual loss and vitreous haemorrhage. However, it does not appear to have a significant different effect on other clinical outcomes such as regression of proliferative sickle retinopathy and development of new ones. No evidence is available assessing efficacy in relation to patient-important outcomes (such as quality of life or the loss of a driving licence). There is limited evidence on safety, overall, scatter argon laser photocoagulation is superior in terms of adverse effects, although feeder vessel coagulation has a better effect in preventing vitreous haemorrhage. Further research is needed to examine the safety of laser treatment compared to other interventions such as intravitreal injection of anti-vascular endothelial growth factors. In addition, patient-important outcomes as well as cost-effectiveness should be addressed.

COMPARING THE OUTCOME OF SINGLE VERSUS MULTIPLE SESSION LASER PHOTOABLATION OF FLAT NEOVASCULARIZATION IN ZONE 1 AGGRESSIVE POSTERIOR RETINOPATHY OF PREMATURITY: A Prospective Randomized Study.

PURPOSE: To compare single versus 2-session laser photoablation for flat neovascularization in cases with Zone 1 aggressive posterior retinopathy of prematurity. METHODS: Twenty-nine Asian Indian infants with aggressive posterior retinopathy of prematurity were randomized; each eye received 1 of 2 methods (29 each in Group A or B) proposed by the PHOTO-ROP group. Group A underwent single session laser to the avascular retina underlying the flat neovascularization by direct laser over the fronds. Group B underwent laser in 2 sessions; first, laser was delivered to the avascular periphery up to the flat neovascularization and 7 days later to the avascular bed exposed by the retraction of the fronds. Outcome and complications between the two groups were compared. RESULTS: Mean birthweight and gestational ages were 1,276 g and 30.1 weeks, respectively. All eyes showed favorable outcome at a minimum 12-month follow-up. Hemorrhages after laser (41.4% vs. 17.2%, P < 0.001) were more common in the single laser group. Large hemorrhages (>1 disk diameter) seen in Group A took longer than 8 weeks to resolve and developed focal fibrosis. CONCLUSION: This study demonstrates that the two-staged laser procedure produces fewer and smaller hemorrhages and no fibrosis compared with a single session. Both methods have comparable favorable outcomes in Asian Indian infants.

Painless indirect argon laser in high risk proliferative diabetic retinopathy.

BACKGROUND: Proliferative retinopathy is an important cause of vision loss in diabetic patients. Incomplete panretinal photocoagulation (PRP) can lead to recurrent proliferation of new vessels. PATIENTS AND METHODS: We retrospectively analysed the outcome of patients with high risk proliferative diabetic retinopathy (PDR) previously treated with slit lamp PRP who underwent indirect fill in argon laser treatment with scleral indentation under anesthesia for persistent neovascular proliferation. RESULTS: Seventeen eyes of ten patients were included. The mean age at diabetes onset was 17.3 years SD 16.2 (range 2-44). All patients reported long standing poor glycemic control (mean HbA1c: 8.5% SD 1.3 range 5.9-10.2). The area of retinal ischemia decreased significantly from 15±7.5 disk areas (DA) before fill-in laser to 3.2±4.2 DA after fill-in laser (p=0.001). The new vessels also regressed significantly after laser treatment 8.6±6.1 DA before treatment versus 6.5±6.4 DA after laser treatment, (p=0.044). Quiescent PDR was reached in 10 eyes (58.8%) at the last visit. CONCLUSIONS: Fill-in indirect argon laser under general anesthesia should be considered to achieve further new vessels regression in high risk PDR patients. Scleral indentation and absence of pain may allow for more extensive laser application.

Pan retinal photocoagulation for proliferative diabetic retinopathy: pattern scan laser versus argon laser.

PURPOSE OF REVIEW: Diabetic retinopathy is the leading cause of visual impairment in working-age adults worldwide. Pan retinal photocoagulation (PRP) has provided an effective treatment to decrease the risk of severe vision loss in patients with proliferative diabetic retinopathy for the past four decades. Pattern scan laser (PASCAL) was developed to minimize the side effects of PRP. The purpose of this review is to discuss the differences between the traditional argon laser and the PASCAL. RECENT FINDINGS: PASCAL can achieve comparable results with the conventional argon PRP in the treatment of patients with diabetic retinopathy. The PASCAL delivery system creates well aligned arrays of retinal lesions in a shorter period. PASCAL provides amore comfortable profile when compared to the argon laser. SUMMARY: The PASCAL is now being substituted for the conventional argon laser for PRP in many clinics. Ophthalmologists should keep in mind that adjusting the PASCAL settings (including the duration, number, and size of laser burns) might become necessary to maintain regression and eliminate recurrence of neovascularization in patients with proliferative diabetic retinopathy. Further studies are needed to determine the parameters for optimal safety and efficacy on the PASCAL.

Acute retinal pigment epithelium detachments after photocoagulation.

PURPOSE: To characterize the morphology of patterned scanning laser (PASCAL) panretinal photocoagulation. METHODS: In this prospective cohort study, patients with proliferative diabetic retinopathy or severe nonproliferative diabetic retinopathy with high-risk characteristics, who were treated with PASCAL panretinal photocoagulation as part of their indicated clinical course, were serially imaged with spectral domain optical coherence tomography. Thirty eyes of 25 patients were studied from 1 hour to 21 weeks after laser treatment. RESULTS: Over a quarter (26.1%) of all treatment spots were imaged by spectral domain optical coherence tomography 1 hour after PASCAL panretinal photocoagulation. At 1 hour (±30 minutes) after PASCAL treatment, spectral domain optical coherence tomography demonstrated retinal pigment epithelium detachment in 23 of 27 eyes (85.2%) and in 36.1% of all imaged laser spots. Detachments occurred preferentially at the photocoagulation edges in 48.4% of pigment epithelium detachments (PEDs). Linear regression analysis revealed that average laser power (Pearson's r = 0.671, P < 0.001) and average laser energy (Pearson's r = 0.588, P = 0.001) were significantly associated with PEDs observed 1 hour after treatment. Pigment epithelium detachments occurred at a rate of 9.2% ± 4.9% at an average power of 0 mW to 400 mW, 37.8% ± 9.5% at 401 mW to 800 mW, 42.1% ± 5.6% at 801 mW to 1,200 mW, and 53.6% ± 5.7% at >1,200 mW. By a 1-week follow-up, no PEDs were observed, and the retinal pigment epithelium appeared morphologically similar to its preoperative structure by 3 weeks. Patient characteristics (study eye, sex, race, diagnosis, age, preoperative blood glucose, hemoglobin A1C, duration of diabetes, and body mass index) and other PASCAL parameters (number of laser applications, spot size, pulse duration, and average laser fluence) were not significantly associated with PEDs. CONCLUSION: Retinal pigment epithelium detachment occurs 1 hour after PASCAL treatment over a wide range of laser settings. Laser power and energy are positively correlated with the occurrence of PEDs, which are no longer observed by 1-week follow-up. Future studies might examine various acute posttreatment time points and directly compare the morphology of PASCAL burns with that of longer pulse-duration laser modalities.

Peripheral sea-fan retinal neovascularization as a manifestation of chronic rhegmatogenous retinal detachment and surgical management.

BACKGROUND: To report the rare occurrence of peripheral retinal sea-fan neovascularization in a patient with chronic rhegmatogenous retinal detachment and describe the surgical management. CASE PRESENTATION: A 29-year-old female patient was referred to our department by her ophthalmologist for investigation and treatment of peripheral retinal neovascularization in her right eye(RE). Visual acuity(VA) at presentation was 20/200 RE and 20/20 LE. Fundoscopy of the RE revealed a chronic inferotemporal retinal detachment and peripheral neovascularization with a sea fan configuration. Fundoscopy of the LE was without any findings. Fluorescein angiography confirmed the sea fan neovascularization in the RE with leakage of the newly formed vessels and peripheral ischemia while the LE did not demonstrate any neovascularization angiographically. Family history was negative for retinitis pigmentosa and haemoglobinopathies. Patient underwent full blood count and haemoglobin electrophoresis to exclude thrombocytosis and sickle cell anaemia, and serum angiotensin-converting enzyme (SACE) measurement to exclude sarcoidosis. Examination with scleral indentation of the RE revealed 2 peripheral small retinal holes close to the ora serrata . The patient underwent a scleral buckling procedure with a small segmental buckle limited to the area of the holes and cryotherapy. Ccryotherapy was not applied to the area with neovascularization and no subretinal fluid drainage was performed. The detached retina was successfully re-attached surgically and the subretinal fluid was gradually absorbed within three months from the time of surgery. Complete regression of neovascularization was evident 2 months postoperatively and VA improved to 20/30. Three years later the clinical and functional findings remain unchanged. CONCLUSION: Our case illustrates the rare but possible association of chronic retinal detachment with peripheral retinal sea-fan neovascularization; although the incidence is rare it may pose diagnostic and treatment dilemmas. In such cases and in the presence of retinal breaks, cryotherapy and a segmental buckle limited to the retinal holes and not on the neovascularization seems to suffice for the regression of the new vessels.