Overview of Gamma Knife

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Overview of Gamma Knife Surgery Dr. Sandra
Vermeulen, M.D.Swedish Cancer InstituteNorthwest
Hospital Gamma Knife CenterSeattle,
WashingtonLearn more atwww.DoctorVermeulen.com
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Years of Clinical Experience
1968The first prototype of Leksell Gamma Knife
was installed in Stockholm, Sweden.
1999Elekta introduces the Leksell Gamma Knife C.
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Leksell Gamma Knife C
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Gamma Knife Surgery
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Leksell Gamma Knife C
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The Treatment Procedure
3. Treatment Planning
1. Frame Fixation
Á
¾
2. Diagnostic Imaging
4. Treatment
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1. Frame Fixation

• Patient Fixation
• Establish Spatial References

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2. Diagnostic Imaging

• The coordinate frame provides stereotactic
  localization
• Digital image transfers to the treatment planning
  computer

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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.

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4. Treatment

• Automatic treatment, supervised by redundant
  safety and verification systems
• Patient communicates via audio visual system

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The Time Factor
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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
  endovasculartechniques extend the capabilities

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Examples of Treated Indications
Functional Targets - Trigeminal nerve

• Vascular
• - Arteriovenous malformations
• Tumors
• - Meningioma
• - Pituitary
• - Acoustic Neuroma
• - Metastatic
• - Gliomas

Research Areas - Intractable pain
targets - Parkinsonian targets - Psychonuerosis
targets - Epilepsy targets - Other functional
targets
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Arteriovenous Malformation
Pre-Gamma Knife Surgery
2 Years Post Gamma Knife Surgery
Courtesy Douglas Kondziolka, MD, MSc, FRCS,
University of Pittsburgh, USA
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Arteriovenous Malformation

• 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-Vs amendable to surgery should be resected

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Acoustic Neuroma
Courtesy Douglas Kondziolka, MD, MSc, FRCS,
University of Pittsburgh, USA
2 Years Post Treatment
Pre-Treatment
6 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.
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Acoustic Neuroma

• 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.

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Pituitary Adenoma
Courtesy Ladislau Steiner, MD, PhD, UVA
Charlottesville, USA, and Christer Lindquist, MD,
PhD, Karolinska Institute, Sweden
Pre-Treatment
54 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.
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Pituitary Adenoma

• 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.

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Metastasis
Courtesy Douglas Kondziolka, MD, MSc, FRCS,
University of Pittsburgh, USA
Pre-Treatment
2 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.
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Metastasis

• 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

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Astrocytoma
Courtesy Ladislau Stenier MD, PhD, Christer
Lindquist, MD, PhD and Dheerendra Prasad MD, UVA
Charlottesville, USA
Pre-Treatment
5 Years Post Treatment
The tumors pattern of spread results in high
radiosurgical treatment failures.
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.
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A Globally Embraced Treatment
202 Leksell Gamma Knife Installed
WorldwideMay 2004
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Gamma Knife Surgery Cumulative Number of
Patients Treated
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Quality of Life

• Non-Invasive
• Less trauma
• Faster recovery
• Minimal hospitalization
• Fewer complications
• Documented Efficacy