Advances in Retinal Tissue Engineering

Retinal degenerations cause permanent visual loss and affect millions world-wide. Current treatment strategies, such as gene therapy and anti-angiogenic drugs, merely delay disease progression. Research is underway which aims to regenerate the diseased retina by transplanting a variety of cell types, including embryonic stem cells, fetal cells, progenitor cells and induced pluripotent stem cells. Initial retinal transplantation studies injected stem and progenitor cells into the vitreous or subretinal space with the hope that these donor cells would migrate to the site of retinal degeneration, integrate within the host retina and restore functional vision. Despite promising outcomes, these studies showed that the bolus injection technique gave rise to poorly localized tissue grafts. Subsequently, retinal tissue engineers have drawn upon the success of bone, cartilage and vasculature tissue engineering by employing a polymeric tissue engineering approach. This review will describe the evolution of retinal tissue engineering to date, with particular emphasis on the types of polymers that have routinely been used in recent investigations. Further, this review will show that the field of retinal tissue engineering will require new types of materials and fabrication techniques that optimize the survival, differentiation and delivery of retinal transplant cells.Harvard Univ, Sch Med, Dept Ophthalmol, Schepens Eye Res Inst, Boston, MA 02114 USABoston Univ, Dept Grad Med Sci, Boston, MA 02215 USAUniversidade Federal de São Paulo, Dept Ophthalmol, BR-09210170 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Ophthalmol, BR-09210170 São Paulo, BrazilWeb of Scienc

Recovery of outer retina in acute idiopathic blind spot enlargement (AIBSE)

Purpose: To report the anatomic and functional recovery of the ellipsoid zone in a case of acute idiopathic blind spot enlargement (AIBSE), which was documented by serial high-resolution optical coherence tomography imaging. Observations: The patient's clinical presentation and follow up visits were documented via Humphrey's Visual Fields, fundus autofluorescence, and high resolution spectral domain optical coherence tomography (SD-OCT). At presentation, Humphrey's Visual Field testing showed an enlarged blind spot in the right eye. Fundus autofluorescence and optical coherence tomography showed an increased peripapillary autofluorescence and loss of the outer retinal layers, respectively. At 3 months a modest improvement in the visual field was observed. This improvement was stable at both the 7 and the 15 month follow up visits. SD-OCT corresponding to the areas of visual field improvement demonstrated recovery of the outer retina. Conclusion and importance: Serial OCT imaging demonstrated anatomic evidence of ellipsoid zone recovery in isolated AIBSE. Anatomic recovery was consistent with the functional gain detected by visual field improvement

Vasculitic central retinal vein occlusion: The presenting sign of seronegative rheumatoid arthritis

Purpose: To report the case of a patient who presented with a vasculitic central retinal vein occlusion (CRVO), which was the result of an undiagnosed systemic inflammatory condition, seronegative rheumatoid arthritis (RA). Observations: The patient presented with reduced vision in the left eye and polyarthralgia. Fundoscopic examination revealed a central retinal vein occlusion (CRVO) with concurrent evidence of vasculitis. Work-up for polyarthralgia included comprehensive serologic testing for connective tissue disease, including Vectra® disease activity (DA) testing. Results of these studies confirmed the diagnosis of seronegative rheumatoid arthritis (RA). Systemic steroid therapy was initiated with subsequent anatomic and visual improvement. Conclusions and importance: We hypothesize that the systemic inflammation—a hallmark of RA—led to the development of a vasculitic CRVO and, thus, the retinal manifestations served as the disease marker that prompted thorough work-up of the patient's disease, even in the face of initial seronegativity. This case serves as a reminder that, in the setting of CRVO and polyarthralgia, systemic inflammatory conditions must be considered as the underlying etiology. Further, this case report highlights our evolving understanding of the role that serologic markers play in the diagnosis and monitoring of RA

Natural History of Drusenoid Pigment Epithelial Detachment Associated with Age-Related Macular Degeneration Age-Related Eye Disease Study 2 Report No. 17

PurposeTo investigate the natural history and genetic associations of drusenoid pigment epithelial detachment (DPED) associated with age-related macular degeneration (AMD).DesignRetrospective analysis of a prospective cohort study.ParticipantsOf the 4203 Age-Related Eye Disease Study 2 (AREDS2) participants, 391 eyes (325 participants) had DPED without late AMD at the time of DPED detection. Genetic analyses included 120 white AREDS2 participants and 145 Age-Related Eye Disease Study (AREDS) participants with DPED.MethodsBaseline and annual stereoscopic fundus photographs were graded centrally to detect DPED, a well-defined yellow elevated mound of confluent drusen ≥433 μm in diameter, and to evaluate progression rates to late AMD: geographic atrophy (GA) and neovascular (NV)-AMD. Five single nucleotide polymorphisms (CFH [rs10611670], C3 [rs2230199], CFI [rs10033900], C2/CFB [rs114254831], ARMS2 [rs10490924]) and genetic risk score (GRS) group were investigated for association with DPED development. Kaplan-Meier analyses and multivariable proportional hazard regressions were performed.Main outcome measuresProgression rates to late AMD and decrease of ≥3 lines in visual acuity (VA) from the time of DPED detection; association of rate of DPED development with genotype.ResultsMean (standard deviation [SD]) follow-up time from DPED detection was 4.7 (0.9) years. DPED was associated with increased risk of progression to late AMD (hazard ratio [HR], 2.36; 95% confidence interval [CI], 1.98-2.82; P < 0.001); 67% of eyes progressed to late AMD 5 years after DPED detection. Drusenoid pigment epithelial detachment was associated with increased risk of ≥3 lines of VA loss (HR, 3.08; CI, 2.41-3.93; P < 0.001) with 46% of eyes experiencing vision loss at 5 years (with or without progression to late AMD). ARMS2 risk alleles (1 vs. 0: HR, 2.72, CI, 1.58-4.70; 2 vs. 0: HR, 3.16, CI, 1.60-6.21, P < 0.001) and increasing GRS group (4 vs. 1) (HR, 12.17, CI, 3.66-40.45, P < 0.001) were significantly associated with DPED development in AREDS. There were no significant genetic results in AREDS2.ConclusionsThis study replicates the results of previous natural history studies of eyes with DPED including the high rates of progression to late AMD and vision loss (regardless of progression to late AMD). The genetic associations are consistent with genes associated with AMD progression

Aspirin Effects on Mortality and Morbidity in Patients With Diabetes Mellitus: Early Treatment Diabetic Retinopathy Study Report 14

Objectives.—This report presents information on the effects of aspirin on mortality, the occurrence of cardiovascular events, and the incidence of kidney disease in the patients enrolled in the Early Treatment Diabetic Retinopathy Study (ETDRS).Study Design.—This multicenter, randomized clinical trial of aspirin vs placebo was sponsored by the National Eye Institute.Patients.—Patients (N=3711) were enrolled in 22 clinical centers between April 1980 and July 1985. Men and women between the ages of 18 and 70 years with a clinical diagnosis of diabetes mellitus were eligible. Approximately 30% of all patients were considered to have type I diabetes mellitus, 31% type II, and in 39% type I or II could not be determined definitely.Intervention.—Patients were randomly assigned to aspirin or placebo (two 325-mg tablets once per day).Main Outcome Measures.—Mortality from all causes was specified as the primary outcome measure for assessing the systemic effects of aspirin. Other outcome variables included cause-specific mortality and cardiovascular events.Results.—The estimate of relative risk for total mortality for aspirin-treated patients compared with placebo-treated patients for the entire study period was 0.91 (99% confidence interval, 0.75 to 1.11). Larger differences were noted for the occurrence of fatal and nonfatal myocardial infarction; the estimate of relative risk was 0.83 for the entire follow-up period (99% confidence interval, 0.66 to 1.04).Conclusions.—The effects of aspirin on any of the cardiovascular events considered in the ETDRS were not substantially different from the effects observed in other studies that included mainly nondiabetic persons. Furthermore, there was no evidence of harmful effects of aspirin. Aspirin has been recommended previously for persons at risk for cardiovascular disease. The ETDRS results support application of this recommendation to those persons with diabetes at increased risk of cardiovascular disease.(JAMA. 1992;268:1292-1300