ABSTRACT
Objective To observe the effect ofvitrectomy (PPV) combined with silicone oil filling on the stability of the tear film.Methods A total of 72 eyes of 36 patients with vitreous hemorrhage and retinal detachment were enrolled in the study with PPV combined with silicone oil filling.The operation and contralateral eyes were set up in the operation group and the control group respectively,each had 36 eyes.The tear film rupture time (BUT),the base tear secretion test or Schirmer Ⅰ test (S Ⅰ T) and corneal fluorescein staining (CFS) were performed at 7,30,60,and 90 days after operation.The difference of BUT,S Ⅰ T and CFS at different time points after the operation of the two groups were compared.Results After operation 7,30 days,S Ⅰ T and CFS increased,BUT staining is shortened in the surgery group,the differences were statistically significant (t=1.78,P＜0.05);after operation 60,90 days,S Ⅰ T,CFS,BUT were same between the surgery group and the contralateral eyes (t=12.39,P＞0.05).Conclusion PPV combined with silicone oil filling can affect the stability of the tear film,which can be recovered to the preoperative level at postoperative 60 days.
ABSTRACT
Purpose: Describe an animal model of dry induced by topical instillation of BAK and evaluate ocular surface biomarkers and histological findings. Methods: Male Wistar rats were used.Topical instillation of 0.2% BAK eyedrops twice a day during 7 days, in the right eye of each animal, while the other eye was taken as control. After 7 days treatment, we performed evaluation of tear film osmolarity, the red phenol thread and ocular surface staining with fluorescein and lissamine green. Afterwards, the animals were sacrificed for tissue extraction and histological evaluation under optical microscopy and H&E staining. Results: Compared with untreated controls, the BAK-group presented tear secretion significantly decreased, increased ocular surface staining by fluorescein and lissamine green and tear film hyperosmolarity (p <0,05). Histological evaluation revealed epithelial thinning and estromal oedema. Conclusions: A toxicity animal model of dry eye induced by topical instillation of benzalkonium chloride, which presents corneal and ocular surface alterations, decreased tear film volume and tear hyperosmolarity as seen in dry eye condition.
Objetivo: Descrever um modelo animal de olho seco induzido pela aplicação tópica de cloreto de benzalcônio (BAC) e avaliar marcadores de integridade da superfície ocular e os achados histológicos. Métodos: Foram utilizados ratos wistar machos adultos. Foi realizada a administração tópica de colírio de BAC 0,2% no olho direito de cada animal duas vezes por dia, durante 7 dias, sendo o olho contralateral tido como controle. Após o tratamento foi realizada a avaliação da osmolaridade do filme lacrimal, o teste de fenol vermelho e a coloração com fluoresceína e lisamina verde. Os animais foram sacrificados e os tecidos extraídos para o estudo histológico da córnea, por microscopia óptica, corada com hematoxilina eosina (H&E). Resultados: Comparados com os controles não tratados o grupo BAC apresentou diminuição significativa na secreção lacrimal, defeitos na integridade epitelial da superfície ocular marcada por corantes vitais, fluoresceína e lisamina verde além do aumento da osmolaridade do filme lacrimal (p < 0,05). À avaliação histológica observou-se diminuição da espessura do epitélio e edema estromal induzidos pela aplicação de BAC. Conclusão: O modelo animal de olho seco por toxicidade induzido pela aplicação tópica de cloreto de benzalcônio apresentou alterações estruturais da córnea e da superfície ocular, diminuição do volume lacrimal e hiperosmolaridade da lágrima características dessa condição.