Osteoid osteoma: Percutaneous laser ablation and follow-up in 114 patients

Purpose: To retrospectively evaluate the effectiveness of interstitial laser ablation (ILA) as a curative treatment of osteoid osteoma. Materials and Methods: Ethical review board approval was obtained for the retrospective study. Informed consent was waived. From June 1994 to June 2004, 114 patients (mean age, 22.3 years) suspected of having osteoid osteoma underwent ILA with a diode laser (805 nm). An optical fiber was introduced into the nidus of the osteoid osteoma, and 400-3000 J of energy was delivered, depending on the size and location of the nidus. Twelve spinal osteoid osteomas were treated; in five of these cases, the nidus was located fewer than 8 mm from the adjacent nerve roots, and slow epidural or periradicular infusion of normal saline was used to avoid thermal damage to neurologic structures. Pain was evaluated with a visual analog scale (VAS) and medication. ILA was considered successful (score, 0) when complete pain relief was achieved (VAS score, < 1) without medication. Results: One week after ILA, 112 patients had a score of 0. One week after ILA, one patient had pain that persisted for 2 months because of reflex sympathetic dystrophy. At follow-up (mean, 58.5 months; range, 13-130 months), six patients had recurrence of pain from 6 weeks to 27 months after the initial ILA. These recurrences were treated successfully with a second ILA. Only one unsuccessful treatment was encountered. Conclusion: Percutaneous ILA is an effective treatment for osteoid osteoma.