ABSTRACT
BACKGROUND: The choroidal vasculature supplies the outer retina and is altered in many retinal diseases, including myopic traction maculopathy (MTM). Choroid health is typically assessed by measuring the choroidal thickness; however, this method has substantial limitations. The choroidal vascularity index (CVI) was recently introduced to provide quantitative information on the vascular flow in the choroid. This index has been evaluated in a wide range of diseases but has not been extensively used to characterize MTM. AIM: This study aimed to investigate the CVI across different stages of MTM and the influence of macular surgery on choroidal perfusion markers in different surgically resolved MTM stages. METHODS: Eighteen healthy myopic eyes in the control group and forty-six MTM eyes in the surgical group were evaluated using enhanced optical coherence tomography (OCT) imaging. Binarized OCT images were processed to obtain the luminal choroidal area (LCA) and stromal choroidal area (SCA), which were used to calculate CVI in the form of a percentage ratio. CVI data were collected at baseline, one and four months postoperatively, and at the final clinical visit. MTM eyes were divided into four stages based on disease severity. The choriocapillaris flow area (CFA) and central subfield thickness (CSFT) were measured along side the CVI. RESULTS: No significant differences were observed between the two groups at baseline, except for visual acuity (p < 0.0001). Surgery significantly improved vision at all postoperative time points (p < 0.0001). At baseline, there were no significant differences in CVI, CFA, or CSFT scores between the control and surgical groups. However, all three measurements were lower at the final visit in the surgical group (p ≤0.0001). No significant differences were found in any of the parameters among the four stages of MTM (p > 0.05). Ultimately, correlation and multivariate linear regression analyses did not reveal any significant association between CVI and visual acuity. CONCLUSIONS: This study did not find significant preoperative differences in CVI between healthy myopic eyes and eyes with MTM. However, the postoperative CVI and CFA values were significantly lower than those of the control eyes. Thus, CVI may not be a good biomarker for surgical outcomes, as the correlation between CVI and visual acuity was not statistically significant.The CVI and CFA decreased after surgery, providing evidence of choroidal changes after surgical management.
Subject(s)
Macular Degeneration , Myopia , Humans , Vitrectomy/methods , Traction , Choroid/blood supply , Tomography, Optical Coherence/methods , Perfusion , Retrospective StudiesABSTRACT
Introducción: La elaboración de preparados farmacéuticos estériles requiere áreas limpias que deben cumplir estándares internacionales para minimizar la contaminación microbiana. Objetivo: Evaluar la calidad bacteriológica del aire de la Unidad de Preparados Farmacéuticos Estériles del Servicio de Farmacia del Hospital Clínico de la Universidad de Chile y establecer niveles de alerta y acción. Material y Métodos: Se monitorearon ocho puntos representativos de la unidad, diariamente entre enero y febrero de 2005 y bisemanal-mente de junio a febrero de 2006. Se estudiaron 839 muestras de aire, recolectadas mediante el método de impacto en placa (equipo MAS-100). Resultados: De las muestras estudiadas, 474 (56,5 por ciento) fueron positivas; de éstas, sólo 17 (3,5 por ciento) estuvieron fuera del rango permitido, porcentaje que representa el 2 por ciento del total. Las muestras de los sitios 1 y 2 (flujo laminar grande y pequeño), que corresponden al área de preparación de preparados estériles fueron negativas. Los sitios 3 (mesón) y 4 (transfer) presentaron ocasionalmente valores superiores a los límites. Los microorganismos más frecuentes fueron Staphylococcus coagulasa negativa, Micrococcus spp y Corynebacterium spp, agentes de la microbiota de la piel y, menor porcentaje, Bacillus spp, agente de la microbiota ambiental. Conclusiones: Desde el punto de vista microbiológico, la calidad del aire de la zona de preparaciones estériles descrita presenta niveles ajustados a estándares internacionales. El establecer niveles de alerta y acción institucionales y la identificación de los microorganismos obtenidos en las áreas más sensibles de la unidad permite cuantificar la carga microbiana y conocer sus componentes para determinar las intervenciones a realizar cuando ellas estén indicadas.
Background: An extremely clean area is required for preparation of sterile pharmaceutical compounds, in compliance with international standards, to minimize the probability of microbial contamination. Aim: To evaluate the bacteriological quality of the air in the Sterile Pharmaceutical Preparation Unit of the University of Chile's Clinical Hospital and to set up alerts and action levels of bacterial growth. Methods: We studied eight representative sites of our Unit on a daily basis from January to February 2005 and twice a week from June 2005 to February 2006. We collected 839 samples of air by impact in the Petri dish. Results: 474 (56.5 percent) samples were positive; 17 (3.5 percent) of them had an inappropriate bacterial growth (2 percent of total samples). The samples from sites 1 and 2 (big and small biosafety cabinets) were negative. The countertop and transfer area occasionally exceeded the bacterial growth limits. The most frequently isolated bacteria were coagulase-negative staphylococci, Micrococcus spp and Corynebacterium spp, from skin microbiota, and Bacillus spp, an environmental bacteria. Conclusions: From a microbiological perspective, the air quality in our sterile preparation unit complied with international standards. Setting institutional alerts and action levels and appropriately identifying bacteria in sensitive areas permits quantification of the microbial load and application of preventive measures.