Proliferative Sickle Cell Retinopathy Research Articles

Indications and outcomes of vitrectomy surgery in a series of 1000 black African eyes

ObjectiveTo determine the common indications for, and outcomes of pars plana vitrectomy surgery among black Africans in a low-resource setting.Methods and AnalysisA retrospective, non-comparative case review was undertaken. Data from...

Knowledge, beliefs and practices regarding sickle cell eye disease of patients at the sickle cell unit, Jamaica.

IntroductionSickle cell disease can result in visually threatening eye disease (proliferative sickle cell retinopathy). This can be prevented with timely eye screening. It is important for patients to understand their role. Our research is to determine the knowledge, beliefs and practices (KBP) regarding eye disease of Sickle Cell patients and the impact of genotype, demographic and socio-economic status.MethodsCross-sectional study at the Sickle Cell Unit, Jamaica during May 2016. Consecutive non-pregnant adults (>18 years of age) attendees, who were not acutely unwell, were invited to participate. A 26-item single interviewer administered questionnaire was used to obtain socio-demographic data, highest level of education completed, employment status, sickle cell genotype, if known, frequency of clinic attendance and patients' knowledge, beliefs and practices. Ten of these were yes/no questions, whereas eight required that they choose correct answers from four choices.ResultsOne hundred subjects were recruited, 72% had homozygous SS disease. Their ages ranged from 18-63 years (mean 34.1 years, SD11.3). Fifty six percent were female. Most (75%) had achieved at least secondary education. The majority (62%) were unemployed. The mean belief score was 3.6/6(60%) and the mean knowledge and practice scores were 3.3/7(47%) and 2.2/5(44%) respectively. Milder genotypes had higher knowledge scores vs the more severe genotypes (4.0 vs 3.2, P=0.013). Only 28% had regular eye examinations; less than 50% had seen an ophthalmologist in the past year. Practice scores were higher in employed than in unemployed patients (2.6 vs 1.9, (P=0.04)). Employed patients were more likely than the unemployed to see their eye doctor for regular eye “examinations” (42.1% vs 19.4%, χ2=6.0, P=0.02). The practice and knowledge scores correlated (r2=0.363, P<0.001) and belief score (r2=0.304, P =0.002), except where 98% believed they should see an ophthalmologist annually, but only 42% did, and 21% had never.ConclusionKnowledge scores were fair, however, the practice was not always in keeping with knowledge.

Proliferative Sickle Cell Retinopathy in SS and SC Hemoglobinopathies: Identification of New Candidate Genes

Retinopathy is one of the major clinical manifestations of sickle cell disease. Its clinical aspects vary depending on the presence or absence of vaso-proliferation, classifying this complication as non-proliferative and proliferative sickle cell retinopathy (PSCR). Endothelial cell activation, injury and dysfunction are importantly involved with pathophysiological mechanisms of sickle cell disease and its complications such as vascular disease. In this study we compared the gene expression profile of endothelial progenitor cells from patients with sickle cell disease and proliferative retinopathy versus without retinopathy. Endothelial Colony-Forming Cells (ECFC) were isolated and cultured from peripheral blood samples of three HbSS patients (Group I) and six HbSC patients (Group II) with proliferative retinopathy as well as from three HbSS patients (Group III) and four HbSC patients (Group IV) without retinopathy. Ophthalmologic evaluation: fundus biomicroscopy, retinal mapping and retinography was performed in all patients. The isolated ECFC were characterized by cobblestone morphology and flow cytometry. RNA was extracted from the cells and transcriptome analysis was performed by next-generation sequencing (RNA-seq). Differentially expressed genes were identified through DESeq2 package. Comparative transcriptome analysis between groups I and III has identified 16 differentially expressed transcripts, 10 negatively regulated and 5 positively regulated. Among these genes, we highlight the most upregulated genes, CDCP1 and NR5A2.The expression of CDCP1 (log2FoldChange = 3,712 and padj value = 0.007) and NR5A2 (log2FoldChange = 3,021 and padj value = 0.019) genes was higher in HbSS patients with PSCR than in patients without retinopathy.On the other side, comparative transcriptome analysis between groups II and IV has identified 34 differentially expressed transcripts, 24 negatively regulated and 10 positively regulated. Among these genes, we highlight the most upregulated genes, ROBO1 and SLC38A5. Importantly, the expression of ROBO1 (log2FoldChange = 4,325 and padj value = 1,35E-11)and SLC38A5 (log2FoldChange = 3,364 and padj value = 1,59E-07)genes was significantly higher in HbSC patients with PSCR than in patients without retinopathy. CDCP1 has been proposed to play a role in regulation of cell differentiation and proliferation through interactions with extracellular matrix.NR5A2 is a constitutively active orphan nuclear receptor. Some of the pathways regulated by nuclear receptors includeangiogenesis, inflammation, and lipid metabolic dysregulation, mechanisms also important in the initiation and development of several retinal diseases.The ROBO1-mediated pathway has been proposed as a target for the treatment of several ocular neovascular diseases. The SLC38A5 gene is the principal mediator of glutamine transport in retinal Müller cells. Since glutamine metabolism is crucial for vessel formation, the blockage of SLC38A5 transporter deserves further attention as an alternative strategy to the inhibition of pathological angiogenesis. Our data suggest that specific pathways can be involved in PSCR of SS and SC hemoglobinopathies. Treatment for PSCR remains palliative, so therapeutic strategies blocking these pathways may contribute to the future development of novel therapies. DisclosuresOzelo:BioMarin: Honoraria, Speakers Bureau; Grifols: Honoraria; Novo Nordisk: Honoraria, Research Funding, Speakers Bureau; Pfizer: Honoraria, Research Funding, Speakers Bureau; Shire: Honoraria, Research Funding, Speakers Bureau; Bioverativ: Honoraria, Research Funding.

Clinical and Ophthalmic Factors Associated With the Severity of Sickle Cell Retinopathy

To identify associations between severity of sickle cell retinopathy (SCR) and other clinical, laboratory, or treatment factors relevant to sickle cell disease (SCD). Retrospective cohort study. We investigated clinical, laboratory, and demographic associations with the severity of SCR in 296 patients seen at both our SCD specialty clinic and our retina clinic. Multivariate multinomial logistic regression was used to estimate the association between each clinical variable and severity of SCR. Multivariate analysis showed that in patients with sickle cell anemia (SCA) genotypes, older age (95% confidence interval [CI], 1.04-1.15; P < .001) and male sex (95% CI, 0.13-0.87; P= .02) were associated with proliferative sickle cell retinopathy (PSR). In patients with genotypic variants, visual symptoms (95% CI, 1.36-21.62; P= .02) were associated with PSR. Laser photocoagulation and vitrectomy surgery, the standard interventions for PSR, were associated with older age (95% CI, 1.05-1.13; P < .001), visual symptoms (95% CI, 1.48-7.40; P= .004), higher hemoglobin level (95% CI, 1.14-1.65; P= .001), and no chronic transfusion (95% CI, 0.16-1.09; P= .08) across the whole cohort. These findings may inform clinicians of the symptoms, systemic findings, and disease-modifying therapies most frequently associated with SCR in SCD patients. Visual symptoms such as blurred vision or floaters were associated with progression of SCR and may be criteria for referral for retinal examination. Chronic transfusion therapy may be protective against the need for retinal laser photocoagulation or vitrectomy. Prospective studies are necessary to further explore risk factors for SCR and to identify which individuals with SCD are at risk for incident or progression of retinopathy.

A comparison of 23-gauge and 20-gauge vitrectomy for proliferative sickle cell retinopathy - clinical outcomes and surgical management.

To report anatomical and functional outcomes in patients with proliferative sickle retinopathy (PSR) who underwent 23-gauge (23G) and 20-gauge (20G) vitrectomy. Retrospective consecutive case series of patients who underwent vitreoretinal intervention for complications of PSR between April 2009 and February 2015. Operations were performed at a tertiary referral centre, Moorfields Eye Hospital. Visual acuity and anatomical success rates were evaluated for PSR complicated by retinal detachment, tractional vitreous haemorrhage and macular hole. Proliferative diabetic retinopathy cases were excluded. A total of 71 eyes (63 patients) underwent vitreoretinal surgery for PSR complications with 26 months mean follow-up. Primary indications were: tractional retinal detachment (TRD, n = 17), TRD with rhegmatogenous retinal detachment (n = 16), rhegmatogenous retinal detachment (n = 5, macula-on: 1, macula-off: 4), vitreous haemorrhage (n = 19), epiretinal membrane (n = 6), and full thickness macula hole (n = 8). Thirty-nine cases underwent 20G vitrectomy, and 23G surgery was performed in 32 eyes. Mean best corrected visual acuity (BCVA) improved from pre-operative 1.30 LogMAR to final BCVA of 0.74 LogMAR (p < 0.01, paired t-test). 23G vitrectomy yielded slightly better 32 vs. 25 ETDRS-letter improvement compared with 20G vitrectomy (p = 0.60, NS, unpaired t-test). 23G was associated with fewer per-operative complications (23G, 18% vs. 20G,13%). The subset of 38 eyes with retinal detachment demonstrated 79% primary reattachment rate, and a smaller BCVA improvement of 3 lines (p = 0.07, paired t-test). Surgical intervention for complicated PSR can preserve and/or improve vision although the degree of visual acuity stabilisation remains guarded in tractional/rhegmatogenous detachments. 23G vitrectomy may give a better functional outcome with lower per-operative complication rates.

Sickle cell retinopathy and other chronic complications of sickle cell anemia: A clinical study of 84 Sub-Saharan African cases (Cameroon)

Sickle retinopathy is a severe complication of sickle cell disease than can lead to blindness. We aim to describe the epidemiology of sickle retinopathy in homozygous sickle cell (SS) African patients and to analyze its association with non-ophthalmologic disease complications of sickle cell anemia. We conducted a nested study within the CADRE cohort in Cameroon. Eighty-four consecutive SS outpatients, aged 10 years and older, with no visual symptoms, underwent an ophthalmologic examination. Mean age was 23±10 years. Clinical and biological features were compared between patients with and without sickle retinopathy. We compared the prevalence of the clinical complications and main biological characteristics in patients with and without sickle retinopathy using a univariate logistic regression. The same analysis was used to compare the patients with non-proliferative sickle retinopathy to those with proliferative sickle retinopathy. Statistical analyses were done using the R software (version 3.1.2). Fifty-two patients (62%) displayed sickle retinopathy, among them 23 (27%) had a non-proliferative sickle retinopathy, and 29 (35%) had proliferative sickle retinopathy. Patients with proliferative sickle cell retinopathy had a mean age of 28±11 years. Sickle retinopathy was associated with higher hemoglobin level (P=0.047) and fewer leg ulcers (P=0.018). Proliferative SR was associated with increasing age (P=0.008) and male sex (P=0.025) independently of the hemoglobin level. Sickle retinopathy is particularly frequent in sub-Saharan sickle cell SS patients, which advocates for early systematic screening.

Correlation of Ultra-Widefield Fluorescein Angiography and OCT Angiography in Sickle Cell Retinopathy

To determine whether the degree of peripheral nonperfusion seen on ultra-widefield (UWF) fluorescein angiography (FA) correlates with measures of macular vascular flow as seen on OCT angiography (OCTA) in sickle cell retinopathy. Prospective, observational study. Patients with sickle cell disease undergoing an eye examination at an urban, tertiary medical center. All patients underwent dilated fundus examination as well as UWF FA and macular OCTA imaging on the same day. The peripheral nonperfusion seen on UWF FA was measured to calculate an ischemic index (visualized nonperfusion/total visualized retinal area× 100%), and OCTA measurements of macular vessel density were recorded. The degree of peripheral nonperfusion and vessel density were then correlated. Correlation between ischemic index as seen on UWF FA and macular vessel density on OCTA. Thirty-six eyes from 19 patients (10 women, 9 men) with a mean age of 30.8 years were included. Sickle genotypes included 14 patients with SS (73.7%), 4 with SC (21.1%), and 1 with β-thalassemia (5.2%). Average ischemic index was 4.4% for all eyes and was found to be higher in patients with sickle SC (8.0%) than in those with sickle SS (3.2%; P= 0.01). Ischemic index also was higher in those with proliferative sickle cell retinopathy (9.3%) than in those without (2.8%; P < 0.01). Ischemic index on UWF FA showed a statistically significant correlation (P < 0.05) with vessel density on OCTA in the temporal subfield of the superficial capillary plexus and in all subfields of the deep capillary plexus. Peripheral nonperfusion seen on UWF FA is greater in those with sickle SC disease and proliferative retinopathy and is correlated with macular vessel density on OCTA, especially the deep retinal plexus.

Expression of the angiogenic mediator, angiopoietin-like 4, in the eyes of patients with proliferative sickle retinopathy.

The recent success of therapies directly targeting the angiogenic mediator, vascular endothelial growth factor (VEGF), for the treatment of proliferative diabetic retinopathy has encouraged clinicians to extend the use of anti-VEGF therapies for the treatment of another ischemic retinal vascular disease, proliferative sickle cell retinopathy (PSR), the most common cause of irreversible blindness in patients with sickle cell disease. However, results from case reports evaluating anti-VEGF therapies for PSR have been mixed. This highlights the need to identify alternative therapeutic targets for the treatment of retinal neovascularization in sickle cell patients. In this regard, angiopoietin-like 4 (ANGPTL4) is a novel angiogenic factor regulated by the transcription factor, hypoxia-inducible factor 1, the master regulator of angiogenic mediators (including VEGF) in ischemic retinal disease. In an effort to identify alternative targets for the treatment of sickle cell retinopathy, we have explored the expression of ANGPTL4 in the eyes of patients with PSR. To this end, we examined expression and localization of ANGPTL4 by immunohistochemistry in autopsy eyes from patients with known PSR (n = 5 patients). Complementary studies were performed using enzyme-linked immunosorbent assays in aqueous (n = 8; 7 patients, 2 samples from one eye of same patient) and vitreous (n = 3 patients) samples from a second group of patients with active PSR. We detected expression of ANGPTL4 in neovascular tissue and in the ischemic inner retina in PSR, but not control, eyes. We further observed elevated expression of ANGPTL4 in the aqueous and vitreous of PSR patients compared to controls. These results suggest that ANGPTL4 could contribute to the development of retinal neovascularization in sickle cell patients and could therefore be a therapeutic target for the treatment of PSR.

Sickle cell retinopathy: improving care with a multidisciplinary approach.

Sickle cell retinopathy (SCR) is the most representative ophthalmologic complication of sickle cell disease (SCD), a hemoglobinopathy affecting both adults and children. SCR presents a wide spectrum of manifestations and may even lead to irreversible vision loss if not properly diagnosed and treated at the earliest. Over the past decade, multidisciplinary research developments have focused upon systemic, genetic, and ocular risk factors of SCR, enabling the clinician to better diagnose and manage these patients. In addition, newer imaging and testing modalities, such as spectral domain-optical coherence tomography angiography, have resulted in the detection of subclinical retinopathy related to SCD. Innovative therapy includes intravitreal injection of an anti-vascular endothelial growth factor (eg, Lucentis® [ranibizumab] or Eylea® [aflibercept]) which appears comparatively safe and efficient, and may be combined with laser photocoagulation (LPC) for proliferative SCR. The effect of LPC alone does not significantly lead to the regression of advanced SCR, although it helps in avoiding hemorrhage and sight loss. This comprehensive article is based on 10-years retrospective (2007–2017) studies. It aims to present advances and recommendations in SCR theranostics while pointing out the requirement of combinatorial approaches for better management of SCR patients. To reach this goal, we identified and analyzed randomized original and review articles, clinical trials, non-randomized intervention studies, and observational studies using specified keywords in various databases (eg, Medline, Embase, Cochrane, ClinicalTrials.gov).

CORRELATION OF MULTIMODAL IMAGING IN SICKLE CELL RETINOPATHY.

To correlate macular findings on spectral domain optical coherence tomography (SDOCT) and optical coherence tomography angiography (OCTA) with quantitative ischemic index calculations on ultra-wide-field fluorescein angiography (UWFFA) in patients with sickle cell retinopathy. In this retrospective case series, SDOCT, OCTA, and UWFFA images of patients with sickle cell retinopathy were evaluated. Eyes were staged based on the Goldberg classification of proliferative sickle cell retinopathy. Focal areas of macular thinning were assessed on SDOCT, macular vessel density was derived from OCTA, and peripheral ischemic index was calculated from UWFFA. Eighteen eyes of 10 patients were included. Mean age was 36.8 ± 16.8 years, and 6 patients (11 eyes) were SS, 3 patients (5 eyes) were SC, and 1 patient (2 eyes) was Sβ thalassemia in hemoglobin electrophoresis. Abnormal macular findings included inner retinal atrophy in 11 eyes (61%) on SDOCT, vascular remodeling and nonperfusion in the superficial and deep retinal capillary plexus in 12 eyes (67%) on OCTA, and macular microvascular abnormalities in 9 eyes (50%) on UWFFA. Sickle cell retinopathy Stage I was identified in 4 eyes (22.2%), Stage II in 8 eyes (44.4%), and Stage III in 6 eyes (33.3%). Mean ischemic index was 14.1 ± 9.1%. Ischemic index was significantly correlated with hemoglobinopathy subtype (23.7 ± 9.8%, 9.3 ± 5.4%, and 16.3 ± 3.2%, for SC, SS, and Sβ thalassemia disease, respectively), stage of sickle cell retinopathy (22.5 ± 9.2%, 12.5 ± 4.9%, and 4.5 ± 0.73% for Stages III, II, and I, respectively), and presence of retinal thinning on SDOCT (17.4 ± 9.7% vs. 8.8 ± 5.1%, respectively). Multimodal imaging can provide a more complete description of the microvascular and structural alterations associated with sickle retinopathy. The correlation between the severity of peripheral nonperfusion and stage and subtype of retinopathy suggests that UWF imaging may be a useful tool in the evaluation of these patients.

Ophthalmic Manifestations of Sickle Cell Disease.

Sickle cell disease (SCD), the most common inherited blood disorder, is characterized by defective oxygen transport. Every part of the eye can be affected by microvascular occlusions from SCD; however, the major cause of vision loss is proliferative sickle cell retinopathy (PSR). Although individuals with the HbSS genotype of SCD manifest more systemic morbidity and those with the HbSC genotype have a milder clinical course, those with HbSC have an increased risk of developing PSR and resultant vision loss. Sickle cell retinopathy has a variable phenotype, even among individuals with the same genotype. Most patients with SCD maintain good vision because the associated retinopathy occurs in the retinal periphery, and any associated "sea fan" neovascularization has a high tendency to autoinfarct and regress. Vision loss from PSR is largely preventable via regular retinal examinations and treatment as indicated. Novel retinal imaging techniques such as wide-field fluorescein angiography, spectral domain optical coherence tomography, and optical coherence tomography angiography can identify evidence of retinal microvascular occlusions in most patients with SCD. Further study is necessary to discover which individuals are at highest risk for vision loss, which of these retinal imaging modalities is clinically important, and which systemic treatments may decrease risk of vision loss from sickle cell retinopathy.

Temporal Macular Atrophy as a Predictor of Neovascularization in Sickle Cell Retinopathy.

To evaluate the association between temporal macular atrophy and the presence of neovascularization in eyes with sickle cell disease (SCD). Retrospective, case-controlled study identifying 64 eyes from 38 consecutive patients with SCD. Dilated funduscopic examination and wide-field fluorescein angiography were used to identify the Goldberg stage of proliferative sickle cell retinopathy. Spectral-domain optical coherence tomography images were analyzed for the presence of temporal macular atrophy. The association between temporal macular atrophy and neovascularization was then evaluated. Temporal macular atrophy had a sensitivity of 27%, a specificity of 67%, a positive predictive value of 83%, and a negative predictive value of 13% for identifying neovascularization. Although the presence of temporal macular atrophy is not sensitive enough to be used as a screening test, if seen in a patient with SCD, the physician should be alerted to the strong possibility that peripheral neovascularization may be present.

Management of Sickle Cell Disease Summary of the 2014 Evidence-Based Report by Expert Panel Members

Yawn, Barbara P.*; Buchanan, George R.†; Afenyi-Annan, Araba N.‡; Ballas, Samir K.§; Hassell, Kathryn L.∥; James, Andra H.¶; Jordan, Lanetta#; Lanzkron, Sophie**; Lottenberg, Richard††; Savage, William J.‡‡; Tanabe, Paula J.§§; Ware, Russell E.∥∥; Murad, M. Hassan¶¶; Goldsmith, Jonathan C.##; Ortiz, Eduardo##; Fulwood, Robinson##; Horton, Ann***; John-Sowah, Joylene## Author Information

Spectral domain optical coherence tomography in patients with sickle cell disease

AimTo evaluate spectral domain optical coherence tomography (SD-OCT) changes in central retina and choroid in patients with sickle cell disease (SCD).MethodsData on visual acuity, severity of sickle cell retinopathy, macular...

Management of sickle cell disease: summary of the 2014 evidence-based report by expert panel members.

Sickle cell disease (SCD) is a life-threatening genetic disorder affecting nearly 100,000 individuals in the United States and is associated with many acute and chronic complications requiring immediate medical attention. Two disease-modifying therapies, hydroxyurea and long-term blood transfusions, are available but underused. To support and expand the number of health professionals able and willing to provide care for persons with SCD. Databases of MEDLINE (including in-process and other nonindexed citations), EMBASE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, CINAHL, TOXLINE, and Scopus were searched using prespecified search terms and keywords to identify randomized clinical trials, nonrandomized intervention studies, and observational studies. Literature searches of English-language publications from 1980 with updates through April 1, 2014, addressed key questions developed by the expert panel members and methodologists. Strong recommendations for preventive services include daily oral prophylactic penicillin up to the age of 5 years, annual transcranial Doppler examinations from the ages of 2 to 16 years in those with sickle cell anemia, and long-term transfusion therapy to prevent stroke in those children with abnormal transcranial Doppler velocity (≥200 cm/s). Strong recommendations addressing acute complications include rapid initiation of opioids for treatment of severe pain associated with a vasoocclusive crisis, and use of incentive spirometry in patients hospitalized for a vasoocclusive crisis. Strong recommendations for chronic complications include use of analgesics and physical therapy for treatment of avascular necrosis, and use of angiotensin-converting enzyme inhibitor therapy for microalbuminuria in adults with SCD. Strong recommendations for children and adults with proliferative sickle cell retinopathy include referral to expert specialists for consideration of laser photocoagulation and for echocardiography to evaluate signs of pulmonary hypertension. Hydroxyurea therapy is strongly recommended for adults with 3 or more severe vasoocclusive crises during any 12-month period, with SCD pain or chronic anemia interfering with daily activities, or with severe or recurrent episodes of acute chest syndrome. A recommendation of moderate strength suggests offering treatment with hydroxyurea without regard to the presence of symptoms for infants, children, and adolescents. In persons with sickle cell anemia, preoperative transfusion therapy to increase hemoglobin levels to 10 g/dL is strongly recommended with a moderate strength recommendation to maintain sickle hemoglobin levels of less than 30% prior to the next transfusion during long-term transfusion therapy. A strong recommendation to assess iron overload is accompanied by a moderate strength recommendation to begin iron chelation therapy when indicated. Hydroxyurea and transfusion therapy are strongly recommended for many individuals with SCD. Many other recommendations are based on quality of evidence that is less than high due to the paucity of clinical trials regarding screening, management, and monitoring for individuals with SCD.

Intravitreal Ranibizumab for Stage IV Proliferative Sickle Cell Retinopathy: A First Case Report.

Purpose. To present the case of a 27-year-old male patient with stage IV proliferative sickle cell retinopathy, treated with one intravitreal injection of ranibizumab, showing regression of the neovascularization and no recurrence at the 9-month follow-up. Methods. A 27-year-old male patient presented with blurred vision and floaters in the right eye since three days. His best corrected visual acuity was 6/18. Ophthalmological examination and fluorescein angiography revealed proliferative sickle cell retinopathy stage IV with vitreous hemorrhage and sea fan neovascularization, as well as ischemic areas at the temporal periphery. Results. The patient was treated with one intravitreal injection of ranibizumab, presenting improvement in the visual acuity from 6/18 to 6/6, resolution of vitreous hemorrhage, and regression of the neovascularization. Additionally, he underwent scatter laser photocoagulation at the ischemic areas. At the 9-month follow-up there was no recurrence, while no adverse effects were noticed. Conclusions. Intravitreal ranibizumab may be a useful adjunct to laser photocoagulation in the management of proliferative sickle cell retinopathy and may permit some patients to avoid pars plana vitrectomy for vitreous hemorrhage.

First Reported Case of Proliferative Retinopathy in Hemoglobin SE Disease.

We report the first case of proliferative sickle cell retinopathy in a patient with hemoglobin SE (Hb SE) disease. Only a few dozen cases of Hb SE disease have been reported previously, and none had evidence of proliferative retinopathy. A 56-year-old African American man presented to our clinic for routine examination and was found to have sea-fan peripheral neovascularization bilaterally without maculopathy. Hemoglobin analysis revealed Hb SE heterozygosity. Sector laser photocoagulation to areas of nonperfusion in both eyes resulted in regression of the peripheral neovascularization over a period of 6 months. Although Hb SE disease is rare, the incidence of Hb SE disease is postulated to rise in the future. Awareness of its potential ocular complications is needed to appropriately refer these patients for screening.

Bevacizumab presurgical treatment for proliferative sickle-cell retinopathy-related retinal detachment.

To report the use of presurgical intravitreal bevacizumab in the context of proliferative sickle-cell retinopathy with retinal detachment. Intravitreal bevacizumab was injected 3 days before the surgical procedure for traction retinal detachment. Vitrectomy, membrane peeling, endolaser, and SF6 gas tamponade were performed. A 37-year-old African American woman presented with hemoglobin sickle-cell disease and temporal retinal detachment with bullous subretinal fluid extending through the fovea associated with an area of active sea-fan retinal neovascularization with preretinal hemorrhage and retinal traction, with 3 associated retinal breaks. The sea-fan neovascularization associated with the traction retinal detachment and the resultant retinal breaks appeared more fibrotic and les vascular than was noted prior to the pre-operative bevacizumab injection. Segmentation and dissection were performed with minimal bleeding, and retinal traction was relieved without difficulty. This was believed to be atypical in the experience of the surgeons. One month postoperatively, vision measured 20/50, and the retina remained attached. Further study is necessary to clarify the role of anti-vascular endothelial growth factor in the treatment of proliferative sickle cell retinopathy associated retinal detachment.

Outcome of transpupillary diode laser photocoagulation for retinal diseases

Background: Diode lasers have been used in ophthalmic practice for several years. They are useful in the management of vasoproliferative retinopathies and have been shown to be comparable in efficacy to the argon laser. Aim: To report on the outcome of transpupillary diode laser treatment for retinal diseases. Patients and Methods: A retrospective study carried out using the case files of patients that had retinal diode laser photocoagulation between June 2011 and May 2012 at the Jos University Teaching Hospital, Jos, Nigeria. Information retrieved included patients' age, sex, diagnosis, indication for retinal laser photocoagulation, prelaser and postlaser visual acuity (VA), best corrected VA, and operative complications. Results: A total of 31 eyes of 21 patients had transpupillary retinal laser photocoagulation during the study period. The commonest indication for retinal laser photocoagulation was proliferative diabetic retinopathy (PDR), and this was seen in 16 eyes (52%). Six eyes (19%) had both PDR and clinically significant macular edema (CSMO), while 3 eyes had CSMO only. Other indications were retinal vein occlusion (RVO) with secondary neovascularization (four eyes), proliferative sickle cell retinopathy (one eye), and traumatic retinal tear (one eye). Following laser therapy in those with diabetic retinopathy, VA improved by at least a line in 6 eyes, remained the same in 13 eyes, and deteriorated in 2 eyes. Neovascular regression was observed in 13 eyes and resolution of macular edema in 3 eyes. In the eyes with RVO, neovascular regression was observed in two eyes. Conclusion: Transpupillary diode laser photocoagulation was beneficial in the treatment of retinal diseases. Fibrovascular proliferation with significant fibrous tissue component was, however, associated with poor response to laser treatment in proliferative retinopathies.

An in vivo morphologic comparison of retinal neovascularization in sickle cell and diabetic retinopathy.

To analyze the in vivo morphology of the sea fan in proliferative sickle cell retinopathy and compare it with the neovascularization in proliferative diabetic retinopathy. Brief case report of spectral-domain optical coherence tomography imaging of a sea fan in a patient with sickle cell anemia and newly diagnosed proliferative sickle cell retinopathy, and morphologic comparison with spectral-domain optical coherence tomography imaging of a neovascular membrane in a diabetic patient with proliferative diabetic retinopathy. Spectral-domain optical coherence tomography imaging revealed that the sea fan is a thicker caliber preretinal fibrovascular membrane involving primarily the retinal nerve fiber and ganglion cell layers. The diabetic membrane has more vitreous adhesions, and it is more closely intertwined with the retina, involving all the retinal layers down to the outer plexiform layer. Spectral-domain optical coherence tomography imaging identified important in vivo morphologic differences between neovascularization in proliferative sickle cell retinopathy and proliferative diabetic retinopathy. These differences were consistent with previous histological studies and may explain the increased risk of tractional retinal detachment in patients with diabetes.