1. 1 Overview of Gamma Knife ® Surgery Dr. Sandra Vermeulen, M.D. Swedish Cancer Institute Northwest Hospital Gamma Knife Center Seattle, Washington Learn more at: www.DoctorVermeulen.com

2. 2 Years of Clinical Experience 1968 The first prototype of Leksell Gamma Knife® was installed in Stockholm, Sweden. 1999 Elekta introduces the Leksell Gamma Knife® C.

3. 3 Leksell Gamma Knife ® C

4. 4 Gamma Knife® Surgery The delivery of a single, high dose of irradiation to a small and critically located intracranial volume through the intact skull. 201 beams intersecting in one focal point

5. 5 Leksell Gamma Knife ® C Helmet Supports Automatic Positioning System Treatment Couch with Mattress Protection Panels Shielding Doors Shielding Cobalt-60 sources Plastic Cover Beam Channel Helmet with Collimators Helmet in Treatment Position

6. 6 The Treatment Procedure 1. Frame Fixation 2. Diagnostic Imaging 3. Treatment Planning 4. Treatment  

7. 7 1. Frame Fixation  Patient Fixation  Establish Spatial References

8. 8 2. Diagnostic Imaging  The coordinate frame provides stereotactic localization  Digital image transfers to the treatment planning computer

9. 9 3. Treatment Planning Team Approach:  The target is defined by the Radiation Oncologist, Neurosurgeon and Medical Physicist.  Care is taken to avoid critical areas of the brain while maximizing the dose to the target.

10. 10 4. Treatment  Automatic treatment, supervised by redundant safety and verification systems  Patient communicates via audio visual system

11. 11 The Time Factor Gamma Knife® Surgery Several Weeks Convalescence Open Surgery Days in ICU Weeks of Hospitalization Diagnosis Symptom

12. 12 Clinical Outcome  Peer reviewed scientific articles shows better or equal results compared with microsurgery  Reproducible results  Fewer complications  Treatment solution for inoperable patients  Combined treatment with microsurgery and endovascular techniques extend the capabilities

13. 13 Examples of Treated Indications Vascular - Arteriovenous malformations Tumors -Meningioma -Pituitary -Acoustic Neuroma -Metastatic -Gliomas Functional Targets -Trigeminal nerve Research Areas -Intractable pain targets -Parkinsonian targets -Psychonuerosis targets -Epilepsy targets -Other functional targets

14. 14 Arteriovenous Malformation Pre-Gamma Knife Surgery 2 Years Post Gamma Knife® Surgery Courtesy: Douglas Kondziolka, MD, MSc, FRCS, University of Pittsburgh, USA

15. 15 Untreated lesions have a 2-4% risk of bleed per year. After Radiosurgery, the risk of bleed remains unchanged until the AVM occludes. 80% of lesions treated with Radiosurgery-occlude within 1-3 years following treatment. A-V’s amendable to surgery should be resected Arteriovenous Malformation

16. 16 Acoustic Neuroma Note: These pictures are provided for education purposes only. Elekta makes no claims as to the effectiveness of the Leksell Gamma Knife ® in these treatments. 2 Years Post Treatment Pre-Treatment6 Months Post Treatment Courtesy: Douglas Kondziolka, MD, MSc, FRCS, University of Pittsburgh, USA

17. 17  90% show no further growth after treatment at 10 years.  Tumors that grow slowly respond slowly to Radiosurgery.  Larger tumors greater than 3.0cm should be surgically removed if they are causing acute symptoms from brainstem compression. Acoustic Neuroma

18. 18 Pituitary Adenoma Courtesy: Ladislau Steiner, MD, PhD, UVA Charlottesville, USA, and Christer Lindquist, MD, PhD, Karolinska Institute, Sweden Pre-Treatment54 Months Post Treatment Note: These pictures are provided for education purposes only. Elekta makes no claims as to the effectiveness of the Leksell Gamma Knife ® in these treatments.

19. 19  Tumors compressing the optic chiasm are not appropriate targets for Radiosurgery.  The optic chiasm maximum safe dose tolerance in a single fraction is less than 10 Gy.  The dose necessary to control a Pituitary Adenoma is in excess of 10 Gy. Pituitary Adenoma

20. 20 Metastasis Courtesy: Douglas Kondziolka, MD, MSc, FRCS, University of Pittsburgh, USA Pre-Treatment2 Months Post Treatment Note: These pictures are provided for education purposes only. Elekta makes no claims as to the effectiveness of the Leksell Gamma Knife ® in these treatments.

21. 21 Appropriate Lesions for Radiosurgery are:  Tumors less than 3cm  Those not associated with a life-threatening mass effect  4 or less tumors simultaneously presenting in the brain with or without whole brain irradiation Metastasis

22. 22 Astrocytoma Courtesy: Ladislau Stenier MD, PhD, Christer Lindquist, MD, PhD and Dheerendra Prasad MD, UVA Charlottesville, USA Pre-Treatment5 Years Post Treatment Note: These pictures are provided for education purposes only. Elekta makes no claims as to the effectiveness of the Leksell Gamma Knife ® in these treatments. The tumors pattern of spread results in high radiosurgical treatment failures.

23. 23 A Globally Embraced Treatment 202 Leksell Gamma Knife® Installed Worldwide May 2004

24. 24 Cumulative Number of Patients Treated Gamma Knife ® Surgery Cumulative Number of Patients Treated

25. 25 Quality of Life  Non-Invasive Less trauma Faster recovery Minimal hospitalization Fewer complications  Documented Efficacy