Stereotactic Radiosurgery (SRS) Jeremy Galle BME 281 October 3 rd 2012

Introduction Also called “stereotaxy” Also called “stereotaxy” Non-invasive form of “surgery” Non-invasive form of “surgery” A type of radiation therapy A type of radiation therapy Called surgery because the results compare to conventional surgery Called surgery because the results compare to conventional surgery A highly precise delivery of radiation A highly precise delivery of radiation Accurate to within 1 to 2 mm of target Accurate to within 1 to 2 mm of target Relies on: Relies on: 3D imaging (such as CT scan) 3D imaging (such as CT scan) Determine location of target Determine location of target Highly focused gamma ray beams Highly focused gamma ray beams Image-guided radiation therapy (IGRT) Image-guided radiation therapy (IGRT) Improves accuracy of delivery Improves accuracy of delivery Has broad range of applications Has broad range of applications

History First stereotactic method developed in London by Sir Victor Horsley and Robert H. Clarke First stereotactic method developed in London by Sir Victor Horsley and Robert H. Clarke “Horsley-Clarke apparatus” “Horsley-Clarke apparatus” 1930s - The apparatus kept receiving slight improvements 1930s - The apparatus kept receiving slight improvements – Two stereotactic devices used for brain surgery in humans – Two stereotactic devices used for brain surgery in humans Henry T. Wycis and Ernest A. Spiegel’s device (American neurosurgeons) Henry T. Wycis and Ernest A. Spiegel’s device (American neurosurgeons) Lars Leksell’s device (Swedish neurosurgeon) – founded Elekta later Lars Leksell’s device (Swedish neurosurgeon) – founded Elekta later 1978 – American physician Russell A. Brown implemented CT use in SRS 1978 – American physician Russell A. Brown implemented CT use in SRS Foundation for current devices Foundation for current devices

Treatment applications Brain tumors Brain tumors Cancerous and non-cancerous Cancerous and non-cancerous Primary and metastatic – spreading Primary and metastatic – spreading Arteriovenous malformations (AVMs) Arteriovenous malformations (AVMs) Tangling of expanded blood vessels Tangling of expanded blood vessels Limits blood flow Limits blood flow Trigeminal neuralgia Trigeminal neuralgia Nerve disorder in face Nerve disorder in face Parkinson’s disease Parkinson’s disease Tremors Tremors Epilepsy Epilepsy Much more… Much more…

Current technology Gamma Knife® by Elekta Gamma Knife® by Elekta Uses 192 to 201 beams of highly-focused gamma rays Uses 192 to 201 beams of highly-focused gamma rays All beams aim at target region All beams aim at target region Linear accelerator (LINAC) machines Linear accelerator (LINAC) machines Deliver high-energy x-rays = photons Deliver high-energy x-rays = photons Uses microwave technology to accelerate photons Uses microwave technology to accelerate photons Novalis Tx™ by Brainwave AG Novalis Tx™ by Brainwave AG XKnife™ by Integra XKnife™ by Integra Axesse™ by Elekta Axesse™ by Elekta CyberKnife® by Accuray CyberKnife® by Accuray Proton beam machine Proton beam machine

Process Injected with contrasting fluid and medicine Injected with contrasting fluid and medicine Patient first gets a CT or MRI scan of the target area Patient first gets a CT or MRI scan of the target area A computer takes the images created and combines them to form a 3-D map of the target area A computer takes the images created and combines them to form a 3-D map of the target area The head frame is then placed on the patient as the operator sees fit The head frame is then placed on the patient as the operator sees fit The patient then lies on a special bed that moves backward into the machine The patient then lies on a special bed that moves backward into the machine While the bed moves into the machine, beams shoot from all different directions towards the target area with the guidance of the 3-D map While the bed moves into the machine, beams shoot from all different directions towards the target area with the guidance of the 3-D map

Process then

Advantages Able to reach tumors that are unreachable by conventional surgery Able to reach tumors that are unreachable by conventional surgery Stops the growth by altering DNA Stops the growth by altering DNA No physical cuts involved (non-invasive) No physical cuts involved (non-invasive) Extremely accurate Extremely accurate Takes less time to complete (30-60 minutes) than comparable therapy treatments Takes less time to complete (30-60 minutes) than comparable therapy treatments More effective than comparable therapy treatments More effective than comparable therapy treatments Cost covered entirely by some medical insurance companies Cost covered entirely by some medical insurance companies Less side effects than other treatments Less side effects than other treatments

Disadvantages Side effects exist Side effects exist Skin problems in target area Skin problems in target area Fatigue Fatigue Hair loss in target area Hair loss in target area Headaches Headaches Brain swelling Brain swelling Tissue damage Tissue damage More… More… Cannot destroy the tumor Cannot destroy the tumor Only stops the growth Only stops the growth Expensive (if not covered by insurance) Expensive (if not covered by insurance) $12,000 average for 1 treatment $12,000 average for 1 treatment $55,000 average for 5 treatments $55,000 average for 5 treatments Results take time Results take time As little as one month to as long as two years As little as one month to as long as two years

Future of the technology Extremely powerful beams that disintegrate tumors Extremely powerful beams that disintegrate tumors Alter DNA so particles dissolve biologically Alter DNA so particles dissolve biologically More accuracy More accuracy No surrounding tissue damage No surrounding tissue damage Much less side effects Much less side effects Less expensive Less expensive 4-Dimensional mapping 4-Dimensional mapping Quicker results Quicker results Quicker procedure times Quicker procedure times

Accuray CyberKnife®

Elekta Gamma Knife®

Proton beam

Works Cited Chen, Viola, Eric Oermann, Saloomeh Vahdat, Jennifer Riben, Simeng Suy, Xia Yu, Sean Collins, and Brian Collins. "CyberKnife with Tumor Tracking: An Effective Treatment for High-Risk Surgical Patients with Stage I Non-Small Cell Lung Cancer." Frontiers in Oncology 2.9 (2012): n. pag. PubMed. Web. 29 Sept Frighetto, Leonardo, Jorge Bizzi, Rafael Annes, Rodrigo Dos Santos Silva, and Paulo Oppitz. "Stereotactic Radiosurgery for Movement Disorders." Surgical Neurology International 3.1 (2012): n. pag. PubMed. Web. 29 Sept "Stereotactic Radiosurgery." MedlinePlus. U.S. National Library of Medicine, n.d. Web. 29 Sept "Stereotactic Radiosurgery Overview." IRSA. N.p., n.d. Web. 29 Sept "Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiotherapy (SBRT)." Radiology Info. Radiological Society of North America, n.d. Web. 29 Sept "Stereotactic Surgery." Wikipedia. Wikimedia Foundation, n.d. Web. 29 Sept Vesper, J., E. Bolke, C. Wille, P. A. Gerber, C. Matuschek, and M. Peiper. "Current Concepts in Stereotactic Radiosurgery - a Neurosurgical and Radiooncological Point of View." European Journal of Medical Research 14.3 (2009): n. pag. PubMed. Web. 29 Sept

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