Resumen: Propósito del estudio: determinar la sensibilidad y especificidad de la resonancia magnética en lesiones de ligamento cruzado anterior, así como las lesiones asociadas mediante los hallazgos artroscópicos. Material y métodos: se trata de un estudio retrospectivo, longitudinal, transversal en el cual se incluyeron 96 pacientes con lesiones de ligamento cruzado anterior (LCA) que fueron sometidos a cirugía artroscópica; los hallazgos artroscópicos se compararon con las imágenes diagnósticas de resonancia magnética así como lesiones asociadas. Resultados: en lesiones de LCA se encontraron los siguientes datos en relación a la concordancia por resonancia magnética nuclear (RMN) y hallazgos artroscópicos; sensibilidad de 93.68%, especificidad de 100%. Valor predictor negativo de 14.28% y un valor predictor positivo de 100%. Conclusión: la RMN es una modalidad de imagen precisa y no invasiva para la evaluación de lesiones de la rodilla, la asociación diagnóstica con el examen clínico es considerablemente alta.

Abstract: Purpose of the study: determine the sensitivity and specificity of magnetic resonance imaging in anterior cruciate ligament injuries and associated injuries through arthroscopic findings. Material and methods: this is a retrospective, longitudinal, cross-sectional study in 96 patients with ACL injuries were included and who underwent arthroscopic surgery; arthroscopic findings were compared with diagnostic magnetic resonance images as well as associated lesions. Results: for ACL lesions the following data were found in relation to the agreement by MRI and arthroscopic findings; 93.68% sensitivity, 100% specificity. Negative predictor value of 14.28% and a positive predictor value of 100%. Conclusion: MRI is an accurate and non-invasive imaging modality for the evaluation of knee injuries, the diagnostic association is considerably high.

A revision is made of the previously poorly studied blackfly fauna from the south-western border of Guyana with Brazil. Notes on the biosystematics of the species found are provided, together with keys and illustrations based on their morphology. Of the 14 species recorded, eight are anthropophilic and two of these (Simulium oyapockense s.l. and S. guianense s.l.) are proven vectors of human onchocerciasis in the nearby Amazonia focus of the disease in neighbouring Brazil.

During studies on the taxonomy of the Simuliidae of Brazil, a new species of Simulium was found. Full descriptions of the adults and pupae of this species are described here, its affinities with other species are discussed and its distribution, biology, and medical importance in Brazil are recorded.