October 2016

Purpose: To describe spectral-domain optical coherence tomography (OCT) methods for quantifying neuroretinal rim tissue in glaucoma and to compare these methods to the traditional retinal nerve fiber layer thickness diagnostic parameter. Methods: Neuroretinal rim parameters derived from three-dimensional (3D) volume scans were compared with the two-dimensional (2D) Spectralis retinal nerve fiber layer (RNFL) thickness scans for diagnostic capability. This study analyzed one eye per patient of 104 glaucoma patients and 58 healthy subjects. The shortest distances between the cup surface and the OCT-based disc margin were automatically calculated to determine the thickness and area of the minimum distance band (MDB) neuroretinal rim parameter. Traditional 150-μm reference surface-based rim parameters (volume, area, and thickness) were also calculated. The diagnostic capabilities of these five parameters were compared with RNFL thickness using the area under the receiver operating characteristic (AUROC) curves. Results: The MDB thickness had significantly higher diagnostic capability than the RNFL thickness in the nasal (0.913 vs. 0.818, P = 0.004) and temporal (0.922 vs. 0.858, P = 0.026) quadrants and the inferonasal (0.950 vs. 0.897, P = 0.011) and superonasal (0.933 vs. 0.868, P = 0.012) sectors. The MDB area and the three neuroretinal rim parameters based on the 150-μm reference surface had diagnostic capabilities similar to RNFL thickness. Conclusions: The 3D MDB thickness had a high diagnostic capability for glaucoma and may be of significant clinical utility. It had higher diagnostic capability than the RNFL thickness in the nasal and temporal quadrants and the inferonasal and superonasal sectors.

Human corneal endothelial cells are derived from neural crest and because of postmitotic arrest lack competence to repair cell loss from trauma, aging, and degenerative disorders such as Fuchs endothelial corneal dystrophy (FECD). Herein, we identified a rapidly proliferating subpopulation of cells from the corneal endothelium of adult normal and FECD donors that exhibited features of neural crest-derived progenitor (NCDP) cells by showing absence of senescence with passaging, propensity to form spheres, and increased colony forming efficacy compared with the primary cells. The collective expression of stem cell-related genes SOX2, OCT4, LGR5, TP63 (p63), as well as neural crest marker genes PSIP1 (p75(NTR)), PAX3, SOX9, AP2B1 (AP-2β), and NES, generated a phenotypic footprint of endothelial NCDPs. NCDPs displayed multipotency by differentiating into microtubule-associated protein 2, β-III tubulin, and glial fibrillary acidic protein positive neurons and into p75(NTR)-positive human corneal endothelial cells that exhibited transendothelial resistance of functional endothelium. In conclusion, we found that mitotically incompetent ocular tissue cells contain adult NCDPs that exhibit a profile of transcription factors regulating multipotency and neural crest progenitor characteristics. Identification of normal NCDPs in FECD-affected endothelium holds promise for potential autologous cell therapies.

Purpose: To analyze the age dependence of the longitudinal modulus of the crystalline lens in vivo using Brillouin scattering data in healthy subjects. Methods: Brillouin scans were performed along the crystalline lens in 56 eyes from 30 healthy subjects aged from 19 to 63 years. Longitudinal elastic modulus was acquired along the sagittal axis of the lens with a transverse and axial resolution of 4 and 60 μm, respectively. The relative lens stiffness was computed, and correlations with age were analyzed. Results: Brillouin axial profiles revealed nonuniform longitudinal modulus within the lens, increasing from a softer periphery toward a stiffer central plateau at all ages. The longitudinal modulus at the central plateau showed no age dependence in a range of 19 to 45 years and a slight decrease with age from 45 to 63 years. A significant intersubject variability was observed in an age-matched analysis. Importantly, the extent of the central stiff plateau region increased steadily over age from 19 to 63 years. The slope of change in Brillouin modulus in the peripheral regions were nearly age-invariant. Conclusions: The adult human lens showed no measurable age-related increase in the peak longitudinal modulus. The expansion of the stiff central region of the lens is likely to be the major contributing factor to age-related lens stiffening. Brillouin microscopy may be useful in characterizing the crystalline lens for the optimization of surgical or pharmacological treatments aimed at restoring accommodative power.

PURPOSE: To describe the clinical course, visual outcome, and prognosis of isolated, idiopathic retinal vasculitis. METHODS: Eighty patients (150 eyes) with isolated, idiopathic retinal vasculitis were included. Demographic data, clinical data, complications at the initial visit and during follow-up, fluorescein angiography, and optical coherence tomography findings were collected from the Massachusetts Eye Research and Surgery Institution (MERSI) database from September 2005 to February 2015. RESULTS: Seventy-five (93.7%) patients required treatment with immunomodulatory therapy. Of those 75 patients, 60 (75%) patients were able to achieve durable remission. Factors which were independently significant predictive of poor visual outcome were lower initial visual acuity (OR: 3.78; 95% CI: 1.75-8.16; P = 0.001), cystoid macular edema (OR: 5.54; 95% CI: 1.81-16.99; P = 0.003), and macular ischemia (OR: 5.12; 95% CI: 1.12-23.04; P = 0.036). CONCLUSION: The majority (67.25%) of our patients enjoyed a good visual outcome (most recent visit best-corrected visual acuity equal to or better than 20/40 and within one line or better from the baseline) with immunomodulatory therapy. We found that cystoid macular edema, macular ischemia, and lower best-corrected visual acuity during the first consultation visit were significant independent risk factors for poor visual outcome.

PURPOSE: To evaluate the efficacy of chlorambucil in the treatment of serpiginous choroiditis. METHODS: Patient records from the Massachusetts Eye Research and Surgery Institution (MERSI) were reviewed from over the past 10 years. In total, 17 patients with the diagnosis of serpiginous choroiditis treated with chlorambucil were identified. QuantiFERON gold was negative in all of them. Chlorambucil was started at 0.15 mg/kg and dosage was titrated up using weekly white blood cell (WBC) count to achieve a target cell number of 3.0-4.5 × 10(9) cells/L. The goal of therapy was to maintain this value for at least 6-9 months. Adverse effects, recurrence, rate of new choroidal neovascularization (CNVM), and visual acuity before and after treatment were recorded. RESULTS: The mean age of the 17 patients with the diagnosis of serpiginous choroiditis treated with chlorambucil was 46 years, and six patients (35%) were male. The mean duration of treatment for chlorambucil was 8.4 months. None of them developed cancer or persistent side-effects, with a mean follow-up of 53 months. Of the patients, 12 (71%) achieved an average of 45 (5-120) months drug-free remission in their last follow-up. Visual acuity of 33 treated eyes remained within two lines of Snellen acuity in 27 eyes (82%), improved in one eye (3%), and deteriorated in five eyes (15%). Leukopenia was the most common side-effect, which was reversible in all cases. CONCLUSIONS: Chlorambucil in a relatively short duration of time, with an escalating dose guided by weekly WBC was well tolerated, as well as effective in preventing recurrence and maintaining vision in patients with serpiginous choroiditis.

Within the next decade, we will see many gene therapy clinical trials for eye diseases progress, which may lead to treatments for thousands of visually impaired people around the world. To target retinal diseases that affect specific cell types, several recombinant adeno-associated virus (AAV) serotypes have been generated and used successfully in pre-clinical mouse studies. Because there are numerous anatomic, and physiologic differences between the eyes of mice and 'men' and because surgical delivery approaches and immunologic responses also differ between these species, we evaluated the transduction characteristics of two promising new serotypes AAV7m8 and AAV8BP2, in retinas of animals that are most similar to those of humans: non-human primates (NHPs). We report that while AAV7m8 efficiently targets a variety of cell types by subretinal injection in NHPs, transduction after intravitreal delivery was mostly restricted to the inner retina at lower doses that did not induce an immune response. AAV8BP2 targets the cone photoreceptors efficiently but bipolar cells inefficiently by subretinal injection. Additionally, we observed transduction of both serotypes in the anterior chamber of the eye and the optic pathway of the brain post intravitreal delivery. Finally, we assessed immunogenicity, keeping in mind that these AAV capsids may be used in future clinical trials. We found that AAV8BP2 had a better safety profile compared to AAV7m8 even at the highest doses administered. Our studies underscore the differences in AAV transduction between mice and primates highlighting the importance of careful evaluation of therapeutic vectors in NHPs prior to moving into clinical trials.

AIM: Eyedroppers deliver medication volumes exceeding conjunctival absorptive capacity, causing spillage and risking ocular/systemic complications. We evaluated piezoelectric microdosing. Results/methodology: Subjects (n = 102) received precision microdroplet delivery of phenylephrine (2.5%) and tropicamide (1.0%): 1 × 1.5 μl, 1 × 6 μl or 2 × 3 μl of each (randomized 1:1:1), into one eye. Contralateral eyes received eyedropper doses of both drugs. Outcomes were pupil dilation (0-60 min) and patient satisfaction. Six-microliter microdosing achieved comparable, and 2 × 3 μl met/exceeded dilation speed and magnitude versus eyedropper. Separately, participants preferred piezoelectric saline self-delivery to eyedroppers, reporting better head-positioning comfort, reduced tearing/overflow and increased likelihood of adhering to ocular medication regimens. CONCLUSION: Piezoelectric microdosing achieves comparable effects as eyedroppers delivering 4-17-fold larger doses. Microdosing may enhance patient adherence to ocular medication regimens while minimizing side effects.

Familial exudative vitreoretinopathy (FEVR) is characterized by delayed retinal vascular development, which promotes hypoxia-induced pathologic vessels. In severe cases FEVR may lead to retinal detachment and visual impairment. Genetic studies linked FEVR with mutations in Wnt signaling ligand or receptors, including low-density lipoprotein receptor-related protein 5 (LRP5) gene. Here, we investigated ocular pathologies in a Lrp5 knockout (Lrp5(-/-)) mouse model of FEVR and explored whether treatment with a pharmacologic Wnt activator lithium could bypass the genetic defects, thereby protecting against eye pathologies. Lrp5(-/-) mice displayed significantly delayed retinal vascular development, absence of deep layer retinal vessels, leading to increased levels of vascular endothelial growth factor and subsequent pathologic glomeruloid vessels, as well as decreased inner retinal visual function. Lithium treatment in Lrp5(-/-) mice significantly restored the delayed development of retinal vasculature and the intralaminar capillary networks, suppressed formation of pathologic glomeruloid structures, and promoted hyaloid vessel regression. Moreover, lithium treatment partially rescued inner-retinal visual function and increased retinal thickness. These protective effects of lithium were largely mediated through restoration of canonical Wnt signaling in Lrp5(-/-) retina. Lithium treatment also substantially increased vascular tubular formation in LRP5-deficient endothelial cells. These findings suggest that pharmacologic activation of Wnt signaling may help treat ocular pathologies in FEVR and potentially other defective Wnt signaling-related diseases.

Sequence variants in CRB2 cause a syndrome with greatly elevated maternal serum alpha-fetoprotein and amniotic fluid alpha-fetoprotein levels, cerebral ventriculomegaly and renal findings similar to Finnish congenital nephrosis. All reported patients have been homozygotes or compound heterozygotes for sequence variants in the Crumbs, Drosophila, Homolog of, 2 (CRB2) genes. Variants affecting CRB2 function have also been identified in four families with steroid resistant nephrotic syndrome, but without any other known systemic findings. We ascertained five, previously unreported individuals with biallelic variants in CRB2 that were predicted to affect function. We compiled the clinical features of reported cases and reviewed available literature for cases with features suggestive of CRB2-related syndrome in order to better understand the phenotypic and genotypic manifestations. Phenotypic analyses showed that ventriculomegaly was a common clinical manifestation (9/11 confirmed cases), in contrast to the original reports, in which patients were ascertained due to renal disease. Two children had minor eye findings and one was diagnosed with a B-cell lymphoma. Further genetic analysis identified one family with two affected siblings who were both heterozygous for a variant in NPHS2 predicted to affect function and separate families with sequence variants in NPHS4 and BBS7 in addition to the CRB2 variants. Our report expands the clinical phenotype of CRB2-related syndrome and establishes ventriculomegaly and hydrocephalus as frequent manifestations. We found additional sequence variants in genes involved in kidney development and ciliopathies in patients with CRB2-related syndrome, suggesting that these variants may modify the phenotype.

PURPOSE: To identify autoantigens in autoimmune retinopathy patients by phage immunoprecipitation sequencing (PhIP-Seq), a new technique for autoantigen discovery. METHODS: PhIP-Seq was used to sequence putative autoantibodies in plasma from 11 patients with autoimmune retinopathy and eight controls. We compared the autoantibodies' molecular weights with those of proteins detected by Western blot. RESULTS: Several autoantigens were found in cases and not detected in the controls. Autoantigens RTN3, PRPF6, TRPC6, and B3GNT8, four proteins expressed in the retina, were detected in plasma as autoantibodies from one patient each and no controls. Only one patient had an autoantibody, B3GNT8 (43.4 kDa), within a similar weight range as that detected by antiretinal antibody Western blot (42 kDa). Autoantibody POLR3A, which has a well-characterized role in scleroderma, was detected in two cases and no controls. CONCLUSION: PhIP-Seq detected autoantigens that are expressed in the retina as well as scleroderma-related autoantigens in autoimmune retinopathy patients.

Transparency of the cornea is indispensable for optimal vision. Ocular trauma is a leading cause of corneal opacity, leading to 25 million cases of blindness annually. Recently, mesenchymal stem cells (MSCs) have gained prominence due to their inflammation-suppressing and tissue repair functions. Here, we investigate the potential of MSCs to restore corneal transparency following ocular injury. Using an in vivo mouse model of ocular injury, we report that MSCs have the capacity to restore corneal transparency by secreting high levels of hepatocyte growth factor (HGF). Interestingly, our data also show that HGF alone can restore corneal transparency, an observation that has translational implications for the development of HGF-based therapy.

PURPOSE: Progressive outer retinal necrosis (PORN) associated with varicella zoster virus (VZV) is usually diagnosed in HIV positive or immunosuppressed patients. We report two cases of immunocompetent patients with necrotizing viral retinitis found to have idiopathic CD4 lymphocytopenia. METHODS: Clinical presentation, examination, imaging, and laboratory testing of two patients with VZV retinitis are presented. RESULTS: An HIV negative patient with history of herpes zoster presented with rapid loss of vision and examination consistent with PORN. PCR testing confirmed VZV. Lymphocytopenia was noted with a CD4 count of 25/mm(3). A second HIV negative patient presented with blurred vision and lid swelling and was found to have peripheral VZV retinitis confirmed by PCR. Laboratory workup revealed lymphocytopenia with a CD4 count of 133/mm(3). CONCLUSIONS: VZV necrotizing retinitis classic for PORN can occur in HIV negative patients. Idiopathic CD4 lymphocytopenia should be considered healthy patients who develop ocular infections seen in the immunocompromised.

In a fibroblast colony model of corneal stromal development, we asked how physiological tension influences the patterning dynamics of fibroblasts and the orientation of deposited extracellular matrix (ECM). Using long-term live-cell microscopy, enabled by an optically accessible mechanobioreactor, a primary human corneal fibroblast colony was cultured on three types of substrates: a mechanically biased, loaded, dense, disorganized collagen substrate (LDDCS), a glass coverslip, and an unloaded, dense, disorganized collagen substrate (UDDCS). On LDDCS, fibroblast orientation and migration along a preferred angle developed early, cell orientation was correlated over long distances, and the colony pattern was stable. On glass, fibroblast orientation was poorly correlated, developed more slowly, and colony patterns were metastable. On UDDCS, cell orientation was correlated over shorter distances compared with LDDCS specimens. On all substrates, the ECM pattern reflected the cell pattern. In summary, mechanically biasing the collagen substrate altered the early migration behavior of individual cells, leading to stable emergent cell patterning, which set the template for newly synthesized ECM.

PURPOSE OF THE STUDY: The purpose of the study was to determine whether there are different patterns of retinal nerve fiber layer (RNFL) thinning as measured by spectral domain optical coherence tomography (SD-OCT) for 4 subtypes of open angle glaucoma (OAG): primary OAG (POAG), normal tension glaucoma (NTG), pseudoexfoliation glaucoma (PXG), and pigmentary glaucoma (PDG) and to compare them with normal controls. MATERIALS AND METHODS: SD-OCT RNFL thickness values were measured for 4 quadrants and for 4 sectors (ie, superior-nasal, superior-temporal, inferior-nasal, and inferior-temporal). Differences in RNFL thickness values between groups were analyzed using analysis of variance. Paired t tests were used for quadrant comparisons. RESULTS: Two hundred eighty-five participants (102 POAG patients, 33 with NTG, 48 with PXG, 13 with PDG, and 89 normal patients) were included in this study. All 4 subtypes of OAG showed significant RNFL thinning in the superior, inferior, and nasal quadrants as well as the superior-temporal and inferior-temporal sectors (all P-values <0.0001) compared with normals. POAG and NTG patients had greater RNFL thinning inferiorly and inferior-temporally than superiorly (P-values: 0.002 to 0.018 and 0.006, respectively) compared with PXG patients. In contrast, PDG patients had greater RNFL thinning superiorly and superior-nasally than inferiorly compared with other OAG subtypes (ie, POAG, NTG, PXG groups, with P-values: 0.009, 0.003, 0.009, respectively). Of the 4 OAG subtypes, PXG patients exhibited the greatest degree of inter-eye RNFL asymmetry. CONCLUSIONS: This study suggests that SD-OCT may be able to detect significant differences in patterns of RNFL thinning for different subtypes of OAG.