RESUMEN
PURPOSE: To clarify the postoperative incidence of macular edema in patients undergoing surgery to repair rhegmatogenous retinal detachment and identify the associated risk factors. METHODS: In this prospective, observational study, 79 patients who underwent surgery to correct rhegmatogenous retinal detachment using pars plana vitrectomy with silicone oil injection were analyzed. Patients were followed up postoperatively at 7, 30, 90, 180, and 365 days. At each visit, optical coherence tomography was performed to assess the presence or absence of macular edema. were analyzed as possible risk factors for macular edema: age, sex, macular status (attached or detached), presence of vitreoretinal proliferation, history of previous intraocular surgery, reported time of symptoms suggestive of rhegmatogenous retinal detachment up to the date of surgery, and the surgical modality performed. RESULTS: The 1-year macular edema prevalence rate was 26.6%. In the adjusted analysis, older patients had a higher risk of macular edema, and each 1-year increase in age increased the risk of macular edema by 6% (95% confidence interval = 1.00-1.12). The macular status, vitreoretinal proliferation, the surgical technique used, prior intraocular surgery, and the intraocular lens status were not identified as risk factors. However, the incidence of macular edema increased up to 180 days after surgery, peaking at 10.6%, and then decreased until 365 days after surgery. CONCLUSION: Macular edema was a common complication after surgery to treat rhegmatogenous retinal detachment, with its incidence peaking between 30 and 180 days after surgery. Age was an important risk factor for macular edema in this cohort.
Asunto(s)
Edema Macular , Desprendimiento de Retina , Tomografía de Coherencia Óptica , Vitrectomía , Humanos , Desprendimiento de Retina/cirugía , Desprendimiento de Retina/etiología , Masculino , Femenino , Edema Macular/etiología , Edema Macular/epidemiología , Persona de Mediana Edad , Factores de Riesgo , Estudios Prospectivos , Vitrectomía/efectos adversos , Vitrectomía/métodos , Incidencia , Adulto , Estudios de Seguimiento , Tomografía de Coherencia Óptica/métodos , Anciano , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Agudeza Visual , Aceites de Silicona/efectos adversos , Aceites de Silicona/administración & dosificación , Factores de Tiempo , Factores de Edad , Adulto JovenRESUMEN
ABSTRACT Purpose: To clarify the postoperative incidence of macular edema in patients undergoing surgery to repair rhegmatogenous retinal detachment and identify the associated risk factors. Methods: In this prospective, observational study, 79 patients who underwent surgery to correct rhegmatogenous retinal detachment using pars plana vitrectomy with silicone oil injection were analyzed. Patients were followed up postoperatively at 7, 30, 90, 180, and 365 days. At each visit, optical coherence tomography was performed to assess the presence or absence of macular edema. were analyzed as possible risk factors for macular edema: age, sex, macular status (attached or detached), presence of vitreoretinal proliferation, history of previous intraocular surgery, reported time of symptoms suggestive of rhegmatogenous retinal detachment up to the date of surgery, and the surgical modality performed. Results: The 1-year macular edema prevalence rate was 26.6%. In the adjusted analysis, older patients had a higher risk of macular edema, and each 1-year increase in age increased the risk of macular edema by 6% (95% confidence interval = 1.00-1.12). The macular status, vitreoretinal proliferation, the surgical technique used, prior intraocular surgery, and the intraocular lens status were not identified as risk factors. However, the incidence of macular edema increased up to 180 days after surgery, peaking at 10.6%, and then decreased until 365 days after surgery. Conclusion: Macular edema was a common complication after surgery to treat rhegmatogenous retinal detachment, with its incidence peaking between 30 and 180 days after surgery. Age was an important risk factor for macular edema in this cohort.
RESUMEN
Chitosan is employed as an absorption enhancer for drug delivery strategies. Aim of this study was to investigate the rapid effects on barrier properties of the intestinal epithelial cell model HT-29/B6. Chitosan (0.005%) induced a fast decrease in transepithelial resistance (R(t)) which was completely reversible after wash-out. Two-path impedance spectroscopy revealed that chitosan affects both, the paracellular (R(para)) and the transcellular (R(trans)) resistance. pH-dependence and inhibition of both effects by negatively charged heparin indicated a chitosan action only in the protonated form. The decrease in R(trans) was mediated by activation of a chloride-bicarbonate exchanger involved in intracellular pH regulation. This activation was coupled to the decrease in R(para) which was associated with an increase in ion permeability and permeability for paracellular flux markers up to 10 kDa. No effects on expression and subcellular distribution of tight junction (TJ) proteins or the actin cytoskeleton were observed. Accordingly, inhibition of actin-myosin interaction, Ca(2+)-dependent intracellular signaling, PKC, PI3K/Akt, MAP kinase p38, and endocytosis pathways did not impair the chitosan effect. These results suggest that the rapid and reversible absorption-enhancing chitosan effect is due to changes in intracellular pH caused by the activation of a chloride-bicarbonate exchanger resulting in the opening of the TJ.