Pseudoaneurysms are rare lesions with a multitude of causes, including infectious, traumatic, and iatrogenic origins. In addition, there are a number of potential treatment options, all of which require consideration to determine the most appropriate management. Historically, surgical intervention has been the method of choice, but because the histopathological features of these lesions make them largely unsuitable for clipping, trapping or excision is often required. More recently endovascular methods have been used, including coil embolization, stent reconstruction, or parent artery occlusion. Although these methods are often successful, situations arise in which they are not technically feasible. The authors describe such a case in a pediatric patient with an iatrogenic pseudoaneurysm. Onyx was used to embolize the lesion and the results were excellent.