RESUMEN
BACKGROUND: Autologous internal limiting membrane transplantation has allowed some cases of macular holes refractory to conventional surgery techniques to be treated. The purpose of this study is to describe the anatomical and functional outcomes of a modification of this technique in a case series of naïve macular hole patients. MATERIAL AND METHODS: A consecutive case series study was performed on patients with naïve macular holes with a diameter greater than 600 µ. Best corrected visual acuity, clinical features of the macular area, and optical coherence tomography were recorded before the operation and at the end of follow-up in all patients studied. All patients underwent 23 Ga core vitrectomy, posterior hyaloid separation, and brilliant-blue assisted internal limiting membrane peeling. A small piece of the internal limiting membrane was peeled off to make a free flap, and this was trasplanted and placed inside the macular hole under perfluorocarbon liquids. Air-fluid exchange was performed and SF6 gas was injected at a non-expansile concentration. RESULTS: The study included 5 eyes of 5 patients who underwent internal limiting membrane autograft. The mean age was 50.6 (SD 12.3) years. Four of the 5 cases had macular hole closure. The case where there was no closure of the macular hole was secondary to trauma. There was an improvement in visual acuity in all patients where the closing of the macular hole was achieved at the end of follow-up. CONCLUSIONS: In this cases series of macular hole patients, the autologous internal limiting membrane transplantation was associated with an anatomical closure of the macular hole and functional improvement in most of the patients studied.
Asunto(s)
Colgajos Tisulares Libres , Membranas/trasplante , Perforaciones de la Retina/cirugía , Adulto , Astrocitos/trasplante , Células Ependimogliales/trasplante , Femenino , Humanos , Masculino , Persona de Mediana Edad , Hexafluoruro de Azufre , Tomografía de Coherencia Óptica , Trasplante Autólogo , Resultado del Tratamiento , Agudeza Visual , VitrectomíaRESUMEN
Müller cells constitute the main glial cell type in the retina where it interacts with virtually all cells displaying relevant functions to retinal physiology. Under appropriate stimuli, Müller cells may undergo dedifferentiation, being able to generate other neural cell types. Here, we show that purified mouse Müller cells in culture express a group of proteins related to the dopaminergic phenotype, including the nuclear receptor-related 1 protein, required for dopaminergic differentiation, as well the enzyme tyrosine hydroxylase. These dopaminergic components are active, since Müller cells are able to synthesize and release dopamine to the extracellular medium. Moreover, Müller-derived tyrosine hydroxylase can be regulated, increasing its activity because of phosphorylation of serine residues in response to agents that increase intracellular cAMP levels. These observations were extended to glial cells obtained from adult monkey retinas with essentially the same results. To address the potential use of dopaminergic Müller cells as a source of dopamine in cell therapy procedures, we used a mouse model of Parkinson's disease, in which mouse Müller cells with the dopaminergic phenotype were transplanted into the striatum of hemi-parkinsonian mice generated by unilateral injection of 6-hydroxydopamine. These cells fully decreased the apomorphine-induced rotational behavior and restored motor functions in these animals, as measured by the rotarod and the forelimb-use asymmetry (cylinder) tests. The data indicate local restoration of dopaminergic signaling in hemi-parkinsonian mice confirmed by measurement of striatal dopamine after Müller cell grafting.