1. CT guided RadioFrequency Ablation in 24 patients with spinal osteoid osteomas J.A.M Bramer, dep. Orthopedic surgery P.D.S. Dijkstra, dep. orthopedic surgery W.R.Obermann, dep. radiology A.H.M. Taminiau, dep. orthopedic surgery

2. CTOS 2005 Osteoid Osteoma in the spine Benign Nidus < 20 mm 10% in spine Pain Scoliosis

3. CTOS 2005 Open surgery Difficult localization Incomplete excision High recurrence rate High complication rate Ozaki, CLINICAL ORTHOP. REL. RES. 2002 Number 397, 394–402

4. CTOS 2005 Radio Frequency Ablation RF ablation under CT guidance Bonopty drilling system Radi Medical Systems, Uppsala, Sweden RF ablation probe Radionics-RFG3C RF-lesion Generator System, Burlington, USA

5. CTOS 2005 RadioFrequency Ablation de Berg, JC Lancet 1995; 350-1.

6. CTOS 2005 Procedure Materials RF needle biopsy drills cannula + stylet RF needle biopsy drills cannula + stylet

7. CTOS 2005 Procedure General Anesthetics

8. CTOS 2005 Procedure Positioning of probe

9. CTOS 2005 S3

10. CTOS 2005 Radio Frequency Ablation

11. CTOS 2005 Study Period1995-2005 Patients24 Follow up54 months (6-120)

12. CTOS 2005 Material and Methods Gender16 ♂, 8 ♀ Median age 23 years (8 – 55) Median size lesion8.5 mm (5 - 15) Volume0,7 cm 3 (0,1-2,5)

13. CTOS 2005 Location 24 locations in 24 patients Cervical 3 Thoracic10 Lumbar 7 Sacral 4

14. CTOS 2005 Distance lesion to vital structures ≤ 2mm in 15 patients : Dural sac12 Foramen10 Vertebral artery 1 Nerve root 1 Hadjipavlou AG Spine. 2003 28(22):E472-7

15. CTOS 2005 Biopsy in all patients No material7 Insufficient material4 Confirming13 Material and Methods

16. CTOS 2005 Location in vertebrae Posterior Pedicle 8 Arch 7 Pars interarticularis 4 Transverse process 2 Anterior Vertebral body3

17. CTOS 2005 Probe positioning Median Tumor size Number of pat. 1x 7 mm 11 2x 10 mm 7 3x4x6x 13 mm 14 mm 222 Procedures

18. CTOS 2005 Results Residual diseasein 5 patients: Second procedure3(3, 9 and 10 months) Third procedure 1(28 months) Open surgery1(6 months)

19. CTOS 2005 Results DISEASE FREE AT FINAL FU 100% NO PAIN

20. CTOS 2005 Results Scoliosis Before procedure58%(14) After procedure17%(4)

21. CTOS 2005 Results ComplicationsNONE Skin Burns0 Neurological deficit0 Sans N, Radiology 1999;212: 687–92.

22. CTOS 2005 C3 mid lesion

23. CTOS 2005 C3 MRI T1

24. CTOS 2005 2nd RF Ablation C3 3 months

25. CTOS 2005 2nd RF Ablation C3 8 months

26. CTOS 2005 Conclusion CT-guided RF ablation of spinal osteoid osteomas is a successful minimal invasive procedure It is safe if the thermo probe is positioned at least 5 mm from vital structures Open surgery in case of tumor adherent to nerve root

27. The combination of percutaneous radiofrequency heat ablation and vertebroplasty seems to be a promising, feasible, minimally invasive technique in the treatment of spinal metastases with cortical defects