Review of experimental models: sinusitis in rabbits

INTRODUCTION: In order to better understand the pathophysiology of rhinosinusitis, several attempts have been made to create the disease in an animal model. Among the studied rodents each has its advantages and disadvantages. Rabbits are considered more appropriate for studies that require surgical manipulation or invasive procedures. OBJECTIVES: To evaluate the most viable experimental model of rhinosinusitis in rabbits to be adopted in future studies. METHODS: An electronic search for studies with experimental models of rhinosinusitis in rabbits published in English and Portuguese between July of 1967 and January of 2013 was conducted in Medline, Pub Med, Cochrane, and CAPES databases, using the keywords "sinusitis", "rabbits", and "polyps". RESULTS: A total of 256 studies were retrieved, but in accordance with the inclusion and exclusion criteria, only ten studies were selected. Many different methods of response assessment were used in these studies. CONCLUSION: To date, there is no ideal experimental model for induction of acute or chronic rhinosinusitis in rabbits, but the rhinogenic model appears to be the most viable option for the continuity of studies of the disease

Avaliação da mucosa sinusal do coelho à presença de implante biodegradável Assessing the maxillary sinus mucosa of rabbits in the presence of biodegradable implants

Pensando em melhorar a qualidade de vida dos pacientes com doenças do humor vítreo, os oftalmologistas começaram a utilizar recentemente implantes biodegradáveis com corticoide. Estes mesmos implantes podem ser uma alternativa no tratamento da RSC e, para isso, realizamos um estudo experimental em seios maxilares de coelhos. OBJETIVO: Avaliar histologicamente a mucosa de seio maxilar de coelhos após a colocação de implante biodegradável de prednisolona. MÉTODO: Dezoito coelhos foram divididos aleatoriamente em dois grupos: Grupo 1: no seio maxilar esquerdo foi inserido um implante biodegradável com prednisolona; Grupo 2: No seio maxilar esquerdo foi inserido um implante biodegradável sem medicação. Os seios maxilares do lado direito serviram como controle. Após 7, 14 e 28 dias foram escolhidos aleatoriamente três coelhos de cada grupo e a resposta tecidual inflamatória foi avaliada. RESULTADOS: Foi encontrada diferença não significativa de inflamação na mucosa, quando comparamos o grupo de coelhos que receberam implantes com e sem medicação com o grupo controle; ou quando comparamos o grupo que recebeu implante com prednisolona com o grupo que recebeu implante sem medicação. CONCLUSÃO: Não foram observados sinais de toxicidade ou inflamação na mucosa do seio maxilar do coelho à presença do implante com ou sem prednisolona.<br>In an attempt to improve the quality of life of patients with vitreous humor disease, ophthalmologists began offering steroid-eluting biodegradable implants to their patients. These implants can be used as an alternative treatment for CRS and this is why this experimental study was carried out on rabbit maxillary sinuses. OBJECTIVE: This study aims to assess the histology of the mucosa of the maxillary sinuses of rabbits after the placement of a prednisolone-eluting biodegradable implant. METHOD: Eighteen rabbits were randomly divided into two groups: group 1 - subjects had drug-eluting implants placed on their left maxillary sinuses; group 2 - subjects had non-drug-eluting implants placed on their left maxillary sinuses. The right maxillary sinuses served as the controls. After seven, 14, and 28 days three rabbits in each group were randomly picked to have their tissue inflammatory response assessed. RESULTS: Levels of mucosal inflammation were not significantly different between the groups with and without drug-eluting implants and the control group, or when the groups with drug-eluting implants and non-drug-eluting implants were compared. CONCLUSION: Signs of toxicity or mucosal inflammation were not observed in the maxillary sinuses of rabbits given prednisolone-eluting implants or non-drug-eluting implants

Estudo histológico e ultra-estrutural da mucosa do seio maxilar em pacientes com rinossinusite crônica e polipose nasossinusal Histology and ultrastructural study of the mucosa of the maxillary sinus in patients with chronic rhinosinusitis and nasosinusal polyposis

Na rinossinusite crônica, a inflamação da mucosa nasossinusal provoca alterações qualitativas e quantitativas do epitélio respiratório que recobre toda a cavidade nasossinusal, levando à manutenção do quadro inflamatório. FORMA DE ESTUDO: Caso-controle. MATERIAL E MÉTODO: Foram avaliados histopatologicamente dez pacientes com rinossinusite crônica (RC) e polipose nasossinusal (PN) por meio da história clínica e alérgica, estudo microbiológico, microscopia óptica, eletrônica de transmissão e varredura. RESULTADO: A diminuição do número de células colunares ciliadas, o aumento das células caliciformes, a diminuição do número de cílios por célula afetada e a metaplasia escamosa foram alterações freqüentemente encontradas nos casos de rinossinusite, explicando a persistência do quadro pela destruição no epitélio e quebra do sistema mucociliar.<br>In chronic rhinosinusitis, inflammation of the rhinosinusal mucosa provokes qualitative and quantitative changes in the respiratory epithelium that lines the entire rhinosinusal cavity, leading to the maintenance of an inflammatory picture. STUDY DESIGN: Case-control. MATERIAL AND METHOD: In the present study we evaluated histopathologically ten patients with chronic rhinosinusitis on the basis of clinical and allergic history, microbiological study, and light, electron and scanning electron microscopy. RESULTS: A reduced number of ciliated columnar cells, an increase in goblet-like cells, a reduction in the number of cilia per affected cell and squamous metaplasia were changes frequently detected in the cases of rhinosinusitis, explaining the persistence of the signs and symptoms due to the destruction of the epithelium and to the breakdown of the mucociliary system