The objective of this study was to detect the presence of local edema and hemorrhage caused by Crotalus durissus terrificus envenoming using magnetic resonance imaging (MRI). Six patients bitten by Crotalus durissus terrificus snakes were treated at the Emergency Unit and Tropical Diseases Unit of Botucatu School of Medicine, UNESP, São Paulo State, Brazil. After receiving specific serotherapy, the patients were submitted to MR of the bite site. Post contrast T1 and T2 spin-echo MRI were obtained revealing the following lesions: edema associated with hemorrhage in subcutaneous and muscular tissue (n=3), edema in subcutaneous tissue (n=2), and perimuscular hemorrhage (n=1). In this study, MR demonstrated a local effect of Crotalus durissus terrificus envenoming in inducing edema and hemorrhage, mainly in muscular tissues and perimuscular areas. These results indicate that Crotalus durissus terrificus venom cause a local muscular tissue damage in human envenoming represented by edema and hemorrhage.

The objective of this clinical study was to evaluate local tissue damage caused by Bothrops sp envenoming in relation to lesion type and damaged tissues using magnetic resonance imaging (MRI). Fifteen patients bitten by Bothrops snakes were treated at the Emergency Unit of the Tropical Diseases Unit at the University Hospital, Botucatu School of Medicine, UNESP, São Paulo State, Brazil. After receiving specific serotherapy, the patients were submitted to MR of the bite site. T1 spin-echo MRI were obtained revealing the following lesions: edema (n=9), edema associated with hemorrhage (n=5), and hemorrhage (n=1). Perimuscular areas (n=6) and subcutaneous tissues (n=5) were the most affected, followed by muscular tissues (n=4). It is important to mention that MRI did not show myonecrosis of the bite site, a widely reported finding in anatomical and histopathological experimental studies.