A craniotomy was scheduled for excision of left-sided intracranial lesion. When Dr. Nelson reached the lesion, he noted an encapsulated mass filled with purulent material. He took two sets of cultures...

A craniotomy was scheduled for excision of left-sided intracranial lesion. When Dr. Nelson reached the lesion, he noted an encapsulated mass filled with purulent material. He took two sets of cultures and proceeded to remove the capsule and purulent collection. He had the circulating nurse look back at the referring physician’s history and she read that the patient had two root canal procedures performed on the left upper side a few months ago.