1. Department of Surgery, Medical School; Pontifical Catholic University of Rio Grande do Sul; Av. Ipiranga, 6681, Porto Alegre/RS, CEP: 90619-900 Porto Alegre Rio Grande do Sul Brazil
2. Department of Morphological Science, Medical School; Federal University of Pelotas; Av. Duque de Caxias 250, Pelotas/RS, CEP: 95030-001 Pelotas Rio Grande do Sul Brazil
3. Department of Morphological Science; Federal University of Pelotas; Av. Duque de Caxias 250 (Prédio Morfologia), Pelotas/RS, CEP: 95030-001 Pelotas Rio Grande do Sul Brazil