RESUMEN
Objective. To create a ureteral obstruction experimental model that can be proved through (99m)Tc-DTPA renal scintigraphy and histopathological studies, without causing total renal function loss. Materials and Methods. Ten New Zealand white rabbits were submitted to a surgical experiment to create a model of unilateral obstruction to urinary flow. Surgery procedure provided unilateral ureteral obstruction (left kidney) to urinary flow and posteriorly was evaluated by (99m)Tc-DTPA renal scintigraphy and histopathological study. (99m)Tc-DTPA renal study was performed to detect and quantify signs of obstruction and to evaluate renal function. Statistical analysis was performed through the Student t-test with a significance level of P<0.05. Results. Nine of the ten rabbits presented left renal unit obstruction and one nonobstructive on the (99m)Tc-DTPA and histopathological studies. All the right renal units, which were not submitted to surgical procedure, were nonobstructed by the studies. There was a general agreement between scintigraphy and histopathological results in both groups. Conclusion. The experimental model promoted the creation of ureteral obstruction in rabbits, confirmed by nuclear medicine scintigraphy and histopathology, and could be used in further studies to better understand urinary obstruction.
RESUMEN
OBJETIVO: Estimar a prevalência dos incidentalomas renais malígnos no Hospital Universitário de Taubaté (HUT), evidenciados pelo ultra-som. MÉTODO: Estudo transversal e retrospectivo de 1559 prontuários de pacientes submetidos a US abdominais, por indicações que não envolviam sinais ou sintomas relacionados ao tumor renal, no período de maio de 1999 a novembro de 2002. Avaliou-se idade, sexo, indicação do exame, característica da lesão. RESULTADOS: Encontrou-se 102 casos de incidentalomas renais, com a prevalência 6,2 por cento de cistos simples e 0,19 por cento de massas malignas do total dos US realizados. CONCLUSÃO: A prevalência do incidentaloma renal maligno no Hospital Universitário foi de 0,19 por cento, sendo menor que a descrita na literatura. O uso de ultra-sonografia como método de rastreamento populacional deve ser mais bem estudado, pois necessita de elevado número de exames para diagnóstico precoce do tumor renal.
BACKGROUND: To estimate the prevalence of kidney incidentalomas detected by ultrasound (US) at the University Hospital of Taubaté. METHODS: Transversal and retrospective study of 1559 patients with abdominal US, with indications that did not lead to signals or symptoms related to renal tumors. This study was done during May of 1999 through November of 2002. We evaluated age, sex, indication of the examination, and characteristic of the injury. RESULTS: One hundred and two cases of kidney incidentalomas were found, with 6.20 percent of kidney cysts and 0.19 percent of malignant kidney tumors. CONCLUSION: The prevalence of incidentaloma with kidney malignancy at the University Hospital was of 0.19 percent. These results are lesser than that have been described in the literature. The use of US as a screening population method has to be better studied, because it is necessary too many examinations to achieve very low positive diagnosis for kidney cancers.