ABSTRACT
PURPOSE: To examine the retinal morphologic features of metamorphopsia caused by epiretinal membrane (ERM) and to determine whether spectral-domain optical coherence tomography (SD-OCT) correlated with metamorphopsia. DESIGN: Retrospective case series. PARTICIPANTS: This study included 19 eyes of 19 patients with ERM diagnosed by clinical ophthalmic findings and SD-OCT. METHODS: The 19 eyes were classified into 3 groups based on Amsler chart results: no metamorphopsia (n = 4), local metamorphopsia (n = 8), and broad metamorphopsia (n = 7). The thickness of the 3 inner retinal layers: inner nuclear layer (INL), outer plexiform layer (OPL), and outer nuclear layer (ONL), on 5 horizontal SD-OCT cross-sections (1 line through the fovea, 2 regularly spaced lines superior to the fovea, and 2 regularly spaced lines inferior to the fovea) were measured using the electronic calipers of the SD-OCT system. MAIN OUTCOME MEASURES: Correlation between INL, OPL, and ONL thickness with metamorphopsia and visual acuity. RESULTS: Metamorphopsia was detected in the same position as edematous areas of the INL with a thickness >50 mum. The maximum INL thickness was relatively significantly different between the subjects with no metamorphopsia and those with local or broad metamorphopsia (vs local, P = 0.06; vs broad, P = 0.04). Visual acuity significantly correlated with both maximum INL thickness (A = -0.681; P = 0.001) and maximum ONL thickness (A = -0.708; P<0.001) in metamorphopsia. CONCLUSIONS: Metamorphopsia induced by ERM may be related to the edematous areas of the INL detected with SD-OCT. The classification of ERM based on INL thickness is a potentially useful indication for surgery. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any of the materials discussed in this article.
Subject(s)
Epiretinal Membrane/diagnosis , Macular Edema/diagnosis , Retinal Neurons/pathology , Tomography, Optical Coherence/methods , Vision Disorders/diagnosis , Aged , Aged, 80 and over , Epiretinal Membrane/complications , Female , Humans , Imaging, Three-Dimensional , Male , Middle Aged , Retrospective Studies , Vision Disorders/etiology , Vision Tests/instrumentation , Visual AcuityABSTRACT
A series of dendritic phenylazomethines (DPA), which have a meso-substituted zinc porphyrin core (DPAGX-ZnP, X = 1-4), were synthesized. Structural studies of these dendrimers were carried out using Tri-SEC (triple detection after size exclusion chromatography), intrinsic viscosity analysis, TEM (tunneling electron microscopy), and molecular modeling calculations by AM1. As a result, a sphere-like structure within a single-nanometer scale (R(h) = 22 A for DPAG4-ZnP) was observed. In addition, encapsulating effects by the DPA shell in the larger dendrimers were confirmed as fundamental properties, based on the UV-vis abosorption spectra, cyclic voltammograms, and 1H NMR spin-lattice relaxation times (T1). The DPAGX-ZnP acts as a multi-metal ion reservoir for SnCl2 and FeCl3. The generation-4 dendrimer (DPAG4-ZnP) can take up to 60 molar amounts of metal complexes around the porphyrin core. A quantitative study of the metal assembling reaction by UV-vis titration revealed stepwise layer-by-layer complexations from the inner imines nearest to the core to the surface. The redox behavior and fluorescence of the zinc porphyrin in these metal-assembled dendrimers also support the stepwise complexation of the metal ion. These analyses suggest that the finely assembled metal complexes in a dendrimer architecture strongly affect the electronic status of the porphyrin core. Results from transient absorption measurements strongly indicate a very fast electron transfer on a subpicosecond time scale between the core and assembled metal complexes.
