Publications

2016

Li D, Taniguchi E, Cai S, Paschalis E, Wang H, Miller J, Turalba A, Greenstein S, Brauner S, Pasquale L, Shen L. Comparison of swept-source and enhanced depth imaging spectral-domain optical coherence tomography in quantitative characterisation of the optic nerve head.. Br J Ophthalmol. 2016;

AIMS: To compare swept-source optical coherence tomography (SS-OCT) and enhanced depth imaging spectral-domain OCT (EDI-OCT) in quantitative assessment of optic nerve head (ONH) parameters. METHODS: In a cross-sectional study, patients with primary open angle glaucoma (POAG) and age-matched control subjects underwent SS-OCT and EDI-OCT B-scans of the ONH in a single visit. Two masked readers independently measured the horizontal and vertical lamina cribrosa depth (LCDH and LCDV, respectively), as well as thinnest Bruch's membrane opening minimum rim width (BMO-MRW) from SS-OCT and EDI-OCT scans. We assessed agreement between SS-OCT and EDI-OCT measurements by linear regression models, Bland-Altman analysis and concordance correlation coefficients (CCC). Intrareader and inter-reader reproducibility was assessed using intraclass correlation coefficients (ICC). RESULTS: One eye from each of 40 patients with POAG and 20 controls were included. All three ONH measurements were higher on SS-OCT than on EDI-OCT, with significant differences in LCDH (mean difference=31.7 µm, p<0.01) and thinnest BMO-MRW (mean difference=20.5 µm, p<0.01). Linear regression models described the agreement between SS-OCT and EDI-OCT measurements with R(2)>0.8 for LCDH among both patients with POAG and controls and for thinnest BMO-MRW among patients with POAG. The CCC was >0.8 overall for each parameter. Intrareader and inter-reader ICCs were ≥0.989 and ≥0.964, respectively, for all parameters. CONCLUSIONS: LCDH, LCDV and thinnest BMO-MRW measurements are not interchangeable between SS-OCT and EDI-OCT, but show good intrareader and inter-reader reproducibility and interdevice agreement for quantitative characterisation of the ONH, particularly among patients with glaucoma.

Ma J, Sun Y, López F, Adamson P, Kurali E, Lashkari K. Blockage of PI3K/mTOR Pathways Inhibits Laser-Induced Choroidal Neovascularization and Improves Outcomes Relative to VEGF-A Suppression Alone.. Invest Ophthalmol Vis Sci. 2016;57(7):3138–44.

PURPOSE: Choroidal neovascularization (CNV) is a major cause of visual loss with age-related macular degeneration (AMD). We evaluated whether blockade of phosphatidyl-inositol-3-kinase (PI3K) and the mammalian target of rapamycin (mTOR), by impairing VEGF-A and other growth factor receptors like platelet-derived growth factor (PDGF), would reduce laser-induced CNV in mice. METHODS: Choroidal neovascularization lesions were induced in C57BL/6 mice. Two groups of mice received oral GSK2126458 (3 mg/kg) or vehicle for 14 days following laser, whereas three groups were treated with GSK2126458 (6 μg/eye), aflibercept (2 μL/eye), or vehicle intravitreally on days 0 and 7 after laser. Vascular leakage was measured by fluorescein angiography (FA) on day 14. Choroidal neovascularization membranes were evaluated on choroidal flat mounts following FITC-dextran perfusion, as well as ED1 and isolectin B4 (IB4) immunohistochemistry. RESULTS: Oral and intravitreal (IVT) GSK2126458 reduced leakage and area of CNV lesions. Greater probability of leaking lesions (∼60%; P < 0.05) was observed in both vehicle groups. Fluorescein isothiocyanate-dextran-labeled total CNV burden area (total lesion area/eye) was reduced ∼67% (P < 0.05) and 35% (P = 0.0528) after oral and IVT GSK2126458 administration. GSK2126458 treatment reduced lesion size by ∼80% (P < 0.05) and 50% (P < 0.05) for oral and IVT control groups. Aflibercept did not alter lesion size (∼27% reduction). CONCLUSIONS: Phosphatidyl-inositol-3-kinase/mTOR is involved in laser-induced CNV angiogenic processes. GSK2126458 effectively reduces CNV size and leakage. Choroidal neovascularization size following IVT GSK2126458 was smaller than after oral administration. Therefore, inhibition of PI3K/mTOR pathways may be more effective due to blockade of action of multiple growth factors.

Nagendran S, Lee G, Fay A, Lefebvre D, Sutula F, Freitag S. Orbital exenteration: The 10-year Massachusetts Eye and Ear Infirmary experience.. Orbit. 2016;35(4):199–206.

The authors report their experience with orbital exenteration surgery at one academic institution over a 10-year period and review the literature. This retrospective cohort study monitored outcomes of all patients who underwent orbital exenteration surgery at Massachusetts Eye and Ear Infirmary between January 2003 and January 2013. Patients with no follow-up data or survival data were excluded from the study. The main outcome measures were surgical complications, disease status of surgical margins, need for adjuvant treatment, local recurrence, metastases and survival. 23 patients with malignancy and 2 with mucormycosis met inclusion criteria for the study. Surgical procedures included non-lid sparing total exenteration (44%), lid-sparing total exenteration (32%), non-lid sparing partial exenteration (8%) and lid-sparing partial exenteration (16%). 44% underwent additional extra-orbital procedures. Survival rates were 72% at 1 year, 48% at 3 years, and 37% at 5 years. Of patients with malignancies, 48% had clear margins after exenteration. There was no statistically significant difference in survival between patients with negative surgical margins compared to positive margins (p = 0.12). Mortality was highest in patients with melanoma (85.7%) and lowest in patients with non-squamous cell lid malignancies (0%). Our study suggests that the type of disease has a much greater impact on the survival of patients undergoing exenteration surgery than the type of exenteration surgery or the disease status of surgical margins. Patients with non-squamous cell lid malignancies and localized orbital disease have the best prognosis for tumor eradication from this radical and highly disfiguring surgery.

Pan J, Liu S, Farkas M, Consugar M, Zack D, Kozak I, Arevalo F, Pierce E, Qian J, Al Kahtani E. Serum molecular signature for proliferative diabetic retinopathy in Saudi patients with type 2 diabetes.. Mol Vis. 2016;22:636–45.

PURPOSE: The risk of vision loss from proliferative diabetic retinopathy (PDR) can be reduced with timely detection and treatment. We aimed to identify serum molecular signatures that might help in the early detection of PDR in patients with diabetes. METHODS: A total of 40 patients with diabetes were recruited at King Khaled Eye Specialist Hospital in Riyadh, Saudi Arabia, 20 with extensive PDR and 20 with mild non-proliferative diabetic retinopathy (NPDR). The two groups were matched in age, gender, and known duration of diabetes. We examined the whole genome transcriptome of blood samples from the patients using RNA sequencing. We built a model using a support vector machine (SVM) approach to identify gene combinations that can classify the two groups. RESULTS: Differentially expressed genes were calculated from a total of 25,500 genes. Six genes (CCDC144NL, DYX1C1, KCNH3, LOC100506476, LOC285847, and ZNF80) were selected from the top 26 differentially expressed genes, and a combinatorial molecular signature was built based on the expression of the six genes. The mean area under receiver operating characteristic (ROC) curve was 0.978 in the cross validation. The corresponding sensitivity and specificity were 91.7% and 91.5%, respectively. CONCLUSIONS: Our preliminary study defined a combinatorial molecular signature that may be useful as a potential biomarker for early detection of proliferative diabetic retinopathy in patients with diabetes. A larger-scale study with an independent cohort of samples is necessary to validate and expand these findings.

Park J, Tischfield M, Nugent A, Cheng L, Di Gioia SA, Chan WM, Maconachie G, Bosley T, Summers G, Hunter D, Robson C, Gottlob I, Engle E. Loss of MAFB Function in Humans and Mice Causes Duane Syndrome, Aberrant Extraocular Muscle Innervation, and Inner-Ear Defects.. Am J Hum Genet. 2016;98(6):1220–7.

Duane retraction syndrome (DRS) is a congenital eye-movement disorder defined by limited outward gaze and retraction of the eye on attempted inward gaze. Here, we report on three heterozygous loss-of-function MAFB mutations causing DRS and a dominant-negative MAFB mutation causing DRS and deafness. Using genotype-phenotype correlations in humans and Mafb-knockout mice, we propose a threshold model for variable loss of MAFB function. Postmortem studies of DRS have reported abducens nerve hypoplasia and aberrant innervation of the lateral rectus muscle by the oculomotor nerve. Our studies in mice now confirm this human DRS pathology. Moreover, we demonstrate that selectively disrupting abducens nerve development is sufficient to cause secondary innervation of the lateral rectus muscle by aberrant oculomotor nerve branches, which form at developmental decision regions close to target extraocular muscles. Thus, we present evidence that the primary cause of DRS is failure of the abducens nerve to fully innervate the lateral rectus muscle in early development.

Vascular endothelial cell growth factor A (VEGF) is a biologically and therapeutically important growth factor because it promotes angiogenesis in response to hypoxia, which underlies a wide variety of both physiological and pathological settings. We report here that both VEGF receptor 2 (VEGFR2)-positive and -negative cells depended on VEGF to endure hypoxia. VEGF enhanced the viability of platelet-derived growth factor receptor α (PDGFRα)-positive and VEGFR2-negative cells by enabling indirect activation of PDGFRα, thereby reducing the level of p53. We conclude that the breadth of VEGF's influence extends beyond VEGFR-positive cells and propose a plausible mechanistic explanation of this phenomenon.

Ramke M, Zhou X, Materne EC, Rajaiya J, Chodosh J. Resident corneal c-fms(+) macrophages and dendritic cells mediate early cellular infiltration in adenovirus keratitis.. Exp Eye Res. 2016;147:144–7.

The cornea contains a heterogeneous population of antigen-presenting cells with the capacity to contribute to immune responses. Adenovirus keratitis is a severe corneal infection with acute and chronic phases. The role of resident corneal antigen-presenting cells in adenovirus keratitis has not been studied. We utilized transgenic MaFIA mice in which c-fms expressing macrophages and dendritic cells can be induced to undergo apoptosis, in a mouse model of adenovirus keratitis. Clinical keratitis and recruitment of myeloperoxidase and CD45(+) cells were diminished in c-fms depleted, adenovirus infected mice, as compared to controls, consistent with a role for myeloid-lineage cells in adenovirus keratitis.

Rodriguez J, Lane K, Ousler G, Angjeli E, Smith L, Bateman K, Abelson M. Diurnal Tracking of Blink and Relationship to Signs and Symptoms of Dry Eye.. Cornea. 2016;35(8):1104–11.

PURPOSE: To assess diurnal changes in the signs and symptoms of dry eyes and their relationship to diurnal interblink interval (IBI) in normal subjects and in subjects with dry eye. METHODS: Blink data were collected from 9:00 AM to 8:00 PM during 2 days of normal activity using an electrocardiogram monitoring device. All subjects recorded ocular discomfort (0-5 scale) and primary activity hourly each day in a diary. Inferior and central fluorescein staining was graded by slit lamp (0-4) at the start and end of each day. Blink activity was detected using an algorithm based on recognition of the waveform corresponding to the kinematic properties of the blink signal. RESULTS: Normal subjects (N = 12) reported negligible symptoms, and results did not show a diurnal change in group hourly IBI. Mean daily IBI for the group with dry eye (N = 15) (4.63 ± 1.63 s) was shorter than that for the normal group (5.28 ± 1.48 s) (P = 0.0483). Correlation of diurnal symptoms and mean hourly IBI was relatively weak (r = -0.248). A repeated-measures model found IBI to be significantly associated with the time of day (P = 0.0028). Inferior corneal staining showed a small but significant diurnal increase for both normal group and group with dry eyes. CONCLUSIONS: Diurnal blink tracking reveals significant trending with symptoms. Diurnal change in IBI may be an appropriate surrogate for symptoms in the study of dry eye.

Uchino Y, Uchino M, Yokoi N, Dogru M, Kawashima M, Komuro A, Sonomura Y, Kato H, Argüeso P, Kinoshita S, Tsubota K. Impact of Cigarette Smoking on Tear Function and Correlation between Conjunctival Goblet Cells and Tear MUC5AC Concentration in Office Workers.. Sci Rep. 2016;6:27699.

The first aim of this study was to clarify whether cigarette smoking affects tear secretion, goblet cell density, and tear MUC5AC concentration. The second purpose was to evaluate the correlations of conjunctival goblet cell density with tear MUC5AC concentration and other ocular surface evaluation factors. This cross-sectional study included 88 office workers. All subjects were required to fill in dry eye and smoking questionnaires, in addition to ocular surface evaluation. Tear wash fluid was collected from inferior fornix, and conjunctival epithelium was obtained by impression cytology. Tear MUC5AC concentration was quantified using enzyme-linked immunoassay, and conjunctival goblet cell density was counted after Periodic-acid Schiff staining. Tear MUC5AC concentration had significant positive correlation with conjunctival goblet cell density (r = 0.181, P = 0.03). In current smokers, Schirmer I test value, goblet cell density and tear MUC5AC concentration were significantly lower than non-smokers. Pack-years of smoking have significant negative correlation with goblet cell density (r = -0.174, P = 0.036) and tear MUC5AC concentration (r = -0.183, P = 0.028). We concluded that smoking might decrease tear secretion, goblet cell density and tear MUC5AC concentration. In addition, MUC5AC concentration in tears depends on goblet cell density in the conjunctiva among office workers.