new technique for intraoperative localization of osteoid osteoma under combined local and general anesthesia using the wake up test

ABSTRACT

In this prospective study, a new method of intraoperative localization was described using the wake up test. Eight patients were included in the study and were diagnosed to have osteoid osteoma. Local infiltration with xylocaine 2% was carried out over the lesion. The soft tissue over the lesion was anesthetized, while the lesion itself was not affected due to its histopathological feature. This gave a clue to localize the lesion after the fentanyl-propofol were given IV to provide general anesthesia. The wake up test and response to surgical stimulation were the guidance to successfully localizing and removing the tumor. The blood propofol concentrating was measured two minutes after injection and after retrieving the response to surgical stimulation. The half life of alpha-phase of distribution was 1.794 minutes indicating rapid distribution of propofol. All patients were satisfied as the characteristic pain completely disappeared postoperatively. The patients were followed up from one-three years [average 2.2 years], no one of the patients experienced the recurrence of the characteristic pain of osteoid osteoma. The wake up technique is a good, feasible and cheap method to localize and assure complete excision of osteoid osteoma. It can be also employed in similar surgeries of the same characteristics