The CyberKnife System is a non-invasive treatment for cancerous and non-cancerous tumors and other conditions where radiation therapy is indicated. It is used to treat conditions throughout the body, including the prostate, lung, brain, spine, head and neck, liver, pancreas and kidney, and can be an alternative to surgery or for patients who have inoperable or surgically complex tumors. CyberKnife treatments are typically performed in 1 to 5 sessions. The CyberKnife System has more than two decades of clinical proof and has helped thousands of cancer patients.

1. CYBERKNIFE
WORLDS NO. ONE ROBOTIC RADIOSURGERY SYSTEM
SUBRATA ROY
SR. RADIATION THERAPIST
HCG CANCER CENTRE MUMBAISUBRATA ROY
SR. RADIATION THERAPIST

2. Radiosurgery Overview
 Radiosurgery is a radiation delivery
procedure that precisely delivers large
radiation doses to tumors and other relevant
anatomical targets in one to five treatments
 Alternative to surgery
 Adjunct to radiotherapy
 Noninvasive,No blade/no blood loss
 No anesthesia related complications
 Minimal complication profile
 Improved patient quality of life
Benefits

3. Radiosurgery Evolution
Frame Based SRS Frame Less SRS Pro Type CK Advance M6 CK

4. Hallmarks of Radiosurgery
High Precision
high degree of reproducible spatial correlation of the
target and the radiation source
High Accuracy (<1mm)
delivering the intended dose within 1 mm of the planned
position
Rapid fall off of radiation dose at the periphery of the
target
Minimizes dose to normal tissues in proximity to the
target
High dose conformity
Minimizes dose to normal tissues

5. Robotic Radiosurgery
Highly precise RT delivery system
 Respiratory tracking
 Fiducial based tracking system
 Intra-fraction motion correction
 Uncomparable dose distribution
 X-ray based image verification
Hypofractionated RT
 High dose short course RT
 Higher BED delivered to target
Radiation source is mounted on a precisely controlled industrial robot. [IDEAL FOR THE MOVING
TARGET]
- Image guidance system(continuous tracking system)
- Eliminates the need of gating techniques and restrictive head frames

6. Fundamentals of Robotic Radiosurgery
 Combines to produce the high conformality, steep dose gradient, non-
coplanar treatment delivery and fully-adaptive intra-fraction motion
tracking essential for accurate robotic radiosurgery treatments
 The robotic manipulator enables routine use of a large number of non-
Iso- centric, non-coplanar beams that are individually targeted at unique
points within the patient without the need to reposition the patient for
each beam
 The continual image guidance during treatment delivery enables the
tracking of patient and target motion
 Unlocks the system to automatically correct beam targeting without
interrupting treatment

7. Historical Landmarks of Radiosurgery (1961-1980)
YEAR AUTHOR LOCATION EVENTS
1961 Leksell Stockholm Invention of Stereotactic
Radiosurgery Using rotating
Orthovoltage Unit
1954 Lawrence Berkeley Use of Heavy Particle treatment for
Pituitary
1962 Kjellberg Boston Use of Proton Beam for Intracranial
Radiosurgery
1967 Leksell Stockholm Invention of Gamma Knife
Radiosurgery using the CO-60 source
1970 Steiner Stockholm Use of Gamma Knife for AVM
1980 Fabrikant Berkeley Use of Gamma Knife for AVM

8. Historical Landmarks of Radiosurgery (1994-2004)
YEAR AUTHOR LOCATION EVENTS
1994 Lax Blomgren Karolinska Stereotactic Treatments of
abdominal Tumors
1994 Adler Stanford First Clinical use of Prototype
Cyberknife
1995 Hamilton Lulu Arizona First report of SBRT case in
North America
2000 Murphy Stanford Introduces image Guided
Radiotherapy
2003 Le/Whyte
Timmerman
Stanford
Indiana
Lung Tumor SBRT
2004 Fuss Salter San Antonio SBRT with the tomotherapy

9. Background of Cyberknife System
Kuka robot KR240
The name derived from the initial letters of “Keller und
Knappich Augsburg”. Founded in 1898
Millimeter >>>>>>>>>>>>>>Sub millimeter
MECHANICAL PRECISION <+/- 0.06 millimeter Sub millimeter
accuracy
2001 August FDA approved for cyberknife
MECHANICAL PRECISION <+/- 0.06 millimeter Sub millimeter
accuracy

10. When an Industrial Robot Meets Neurosurgeons Hand
INDUSTRIAL KUKA-240 ROBOT WITH GROUP EFFORT OF NEUROSURGEON TEAM
MODERN CYBERKNIFE SYSTEMPRO TYPE CYBERKNIFE
Derived from letters of the company name “Keller und Knappich Augsburg”.

11. Historical Notes On Cyberknife
 The Cyberknife was invented in 1990 by John R.
Adler.
A professor of Neurosurgery and Radiation Oncology at Stanford
University.
 First patient treated in 1994

12. Cyber knife Robotic System Overview
Cyberknife Components
Manipulator
 KUKA robot with 6 axes of rotation
 < 0.2 mm Mechanical precision
 Manual control with “Teach pendant”
 Programmable robot positions
Linac
 6 MV
 No flattening filter
 Dose Rate = 1000 cGy/Min
 Sealed ion chambers (since 2010)
Collimation system
 12 Fixed cones or IRIS variable collimator
 Collimator exchange table
Robo couch
6 degrees of motion
kV X-ray Target Location System
Floor mounted flat panel imagers
Perkin Elmer A Si panels
1024 x 1024 pixels
41 x 41 cm physical dimensions
Ceiling mounted X-ray tubes
Oil cooled
2.5 mm Al filtration
up to 125 kV, 320 mA, 500 ms
Synchrony Respiratory Tracking System
Ceiling mounted LED camera array
Treatment Planning System
Multi-Plan V3.5

13. Cyberknife VSI System Overview
CYBERKNIFE SYSTEM
Robotic manipulator precision 0.12mm
Overall targeting accuracy(static target) Max ≤0.95mm
Overall targeting accuracy(target with organ
motion)
Max ≤1.5mm
Beam collimation Variable aperture/fixed circular collimators
Dose-rate 1000MU/min
Image detectors Dose calculation algorithm Amorphous silicon flat panel detectors with pixel
size
0.4x0.4mm
Robot path traversal Nodes selected during planning
Patient positioning system Fully integrated 5-DOF standard treatment couch
Image registration and tracking methods 6D skull, Xsight spine, Fiducial, Synchrony, Xsight
Lung, Lung LOT,

14. Cyberknife Main Components
 Target Locating System
 Operator Control Systems
 Precision Treatment Planning System
 LINAC and Control System
 Treatment Manipulator System
 Standard Treatment couch
 Image Detectors
 Robotic Collimator Exchanger
 Teach Pandent
 Power Distribution Unit
 E-Stop interlock Control Chassis
 Uninterruptable Power Supply
 Miscellaneous Equipment

15. Cyberknife Main Components
Cyberknife Robotic Radiosurgery System

16. Target Locating System
 Provides information about the
location of the treatment target
throughout the treatment process.
 2 X-ray Sources mounted on 45
degree overhead to provide orthogonal
pair of X-ray images to compare with
the DRR images
TLS Includes:-
• X-ray Sources and Generators
• Digital X-ray Detectors
• Isopost Callibration Tools
• Detector windows
Electrical 3 phase
-Circuit 40-150 kv
-Nominal tube Voltage Large Focus:1.2mm
Small Focus:0.6mm
-Nominal Focal Spot value Large Focus:100kW
Small Focus:40kW
-Nominal anode input
power
2.5mm
Aluminum Filter Synchronous and
Asynchronous
Firing Modes Fixed Aperture
Collimator Type

17. Operator Control System
The Operator Control system controls the treatment Delivery process according to the treatment
plan.
Operator Control system Includes:-
• Treatment Delivery Computer
• User Control Console Equipment
 The Treatment delivery Computer used for delivering and monitoring the treatment includes a flat
panel monitor, keyboard are located in the control room.
 Operator Control Panel to turn on the high voltage to the linac and monitor the status of the
treatment beam
 This also includes Emergency Stop button for handling the emergency situation.

18. Precision Treatment Planning System
Accuracy Precision system is a highly Interective
workflow based software application responsible for
the radiosurgery and high precision radiotherapy
Planning .
This System allows to load and fuse the
images, draw contours and Optimize
Treatment Plan

19. LINAC and Control System
LINAC mounted in the X-ray head delivers the radiation
treatment to the patient
The X band LINAC provides a collimated beam of 6MV X-rays
consists of an electron gun and series of microwave cavities
under vaccum.
Compact size of the LINAC allows the robotic manipulation
with 6 Degrees of Freedom.
Dose Rate: 1000MU/min

20. Treatment Manipulator System
 Has 6 degrees of freedom
 Can position the linac to more than 100 specific
locations, or nodes
 Each node has 12 possible approach angles
 Translating to over 1200 possible beam
positions

21. Standard Treatment couch
 Used to Position the patient for Treatment
 Capable of moving the patient under Computer Control
in 3 Translation and 2 roatation directions.
 Maximum Load- 350lb or 159 kg
Standard Treatment couch

22. Image Detectors
Amorphous silicon based detectors capture high-resolution anatomical images
throughout the treatment. These images are compared to previously generated
DRR's to determine real-time patient positioning and target location.
The imaging system then corrects changes in patient's position, by sending a
command to the robotic manipulator.

23. Robotic Collimator Exchanger
 Required for Iris Collimator.
 Includes Exchange functionality that allows the system to automatically change between the
iris collimator housing and fixed collimator housing.
 A secondary collimator housing allows automatic change between fixed collimators
Table consists of 12 fixed cones and housings of
‘Fixed’ and ‘Iris’ Collimator
Secondary Collimator
The fixed collimators attach to a secondary collimator
housing which is mounted on the x-ray head .
The effective collimation sizes are
5,7.5,10,12.5,15,20,25,30,35,40,50,60 mm in 800 mm
SAD.

24. The Iris Dynamic Collimator
Robotic Radiosurgery using more than one circular collimator can
improve treatment plan quality and reduce total monitor units (MU).
The rationale for an iris collimator that allows the field size to be varied
during treatment delivery is to enable the benefits of multiple-field-size
treatments to be realized with no increase in treatment time due to
collimator exchange or multiple traversals of the robotic manipulator by
allowing each beam to be delivered with any desired field size during a
single traversal.
The aperture reproducibility is < or =0.1 mm at the lower bank, diverging to < or
=0.2 mm at a nominal treatment distance of 800 mm from the beam focus

25. Teach Pandent
Therapists Perspective:
External Modes Only
Used to keep robot in PERCH(HOME)
position BEFORE/AFTER treatment
completion.
Any interruptions during the treatment, for re-
positioning of the patients/removing the
patients.

26. Power Distribution Unit
It Supplies power to all components of the Cyberknife , It is located in the
Equipment Room.

27. E-Stop interlock Control Chassis
The ESCC performs a wide variety of hardware functions ,as well as functioning as
a central point For E-Stop signals .
It is Located On the Treatment Room.

28. Uninterruptable Power Supply
The UPS power Supply provides the backup power to
the Treatment Delivery Computer and Cyberknife
System Data Server for 5 minutes.
It is Located in the Equipment Room

29. Miscellaneous Equipment
 The Conduit Port ( For Connecting Cables From Treatment Room To
Control Room)
 Closed Circuit TV for monitoring the Patient(4 Recommended)
 Medical Gas Lines
 Intercom System

30. How Ck System Differs From Other Radiosurgery System
 The Cyber Knife system uses the combination of a robotics and image
guidance to deliver concentrated and accurate beams of radiation to
intracranial and extracranial targets, many of which are inoperable with sub-
millimeter accuracy.
 The robotic arm is highly flexible, allowing access to tumors in difficult-to-
reach locations.
 The Cyber Knife, unlike other stereotactic radiosurgery systems, is able to
locate and track the position of the tumor without the use of an invasive
stereotactic head frame or stereotactic body frame.
 The system compensates for the patient’s respirations and movement during
treatment, constantly ensuring accurate targeting for the delivery of radiation
beams.

31. Cyberknife in Competition with Gamma Knife
Key Points Cyberknife Gamma Knife Comments
Immobilization
Device
Orfit Rigid frame Cyberknife has favorable orfit mask system.
Radiation
Source
6 MV Linac Co60 Radioactive Source Gamma Knife need to change the sources
every 5-6 year
Planning
Procedure
Inverse Planning No complex Planning Favorable Dosimetry In Cyberknife
Planning
Method
Complex Simple Even Neurosurgeons can plan on gamma
Knife
Isodose
Prescription
Usually 80-95% Usually 50% Gamma Knife more dose hetaroginity
Fractions May treat Multiple # Single # Radiobiology favorable in Cyberknife
Tumour Size Larger Lesions can be
Treated
Only smaller lesions can be
treated
Increased indications with cyberknife
Energy Source Electricity Radiation Gamma Knife can work with less electricity
Image
verrification
Possible Not Possible Even Intrafraction movement can be
corrected
Indications Extra and IntraCranial Only Brain Lesions Cyberknife more Economical

32. Cyberknife Paybacks compare Other Radiotherapy System
Criteria Cyberknife
Stereotactic
Radiosurgery
Conventional
Radiotherapy
Linac Based
Stereotactic
Radiosurgery
Proton Therapy
Daily Dose
Delivery
5-2 Gy/# 1.8-3.0 Gy/# 5.0-2.0 Gy/# 1.8-2.0 Gy/#
No Of
Fractions
3-5 Days 6-7 Weeks 3-5 Days 6-7 Weeks
Accuracy
of Tissue
margin
1.5 millimeters 20-30 millimeters 1-5 millimeters 20-30 millimeters
No of
radiation
Beam
100-200+
Beam
Placement
2-7 Beams 5-15 Beams 2-3 Beams
Continuous
Correction
YES NO NO NO

33. Advantages of Cyberknife System
 Painless treatment procedure.
 Noninvasive.
 No blood loss.
 Immediate return to normal routine.
 Completely frameless.
 No hospitalization.
 Minimal radiation exposure to healthy tissues and organs.
 Even if tumors have received the maximum allowed dosage of
radiation, they can still be treated.
 The ability to give stronger, more accurate doses of radiation directly
to the tumor means that the number of treatment doses can be
shortened.
 The risk of radiation damage to normal surrounding healthy tissues is
minimized greatly.
 Increased patient comfort due to the elimination of the invasive head
frame.

34. Cyberknife Confirmality
Non- Iso centric Beam Delivery
 Highly collimated beams
 Non-convergent beams
 Superior conformality while
 Maximizing homogeneity
Non-Coplanar Beam Delivery
 Automatically minimizes entrance/exit beam
interactions.
 No patient or linac re-positioning required.

35. Redefining Accuracy
Traditional Definition: Mechanical Accuracy
New Definition: Clinical Accuracy
Mechanical Accuracy = 0.2 mm
Sub-Millimeter Clinical Accuracy
The overall average Cyber Knife System error is less than 0.95 mm RMS when CT slice spacing of 1.25 mm or less is
used. When used with the Synchrony® Respiratory Tracking option, the overall average Cyber Knife System error is less
than 1.5 mm RMS for CT slice spacing of 1.25 mm or less.

36. Real Time Image Guidance
The Cyber Knife System uses imaging software to track and
continually adjust treatment for any movement of the patient or
tumor. Continually detects, tracks, and corrects for tumor motion
throughout treatment, and there are several options to accomplish
following objectives
 Taking X-rays periodically during treatment of bony anatomy.
 Using metal markers placed within the body.
 As exemplified by lung cancer, using differences in soft tissue
densities.
This Robotic Radiosurgery system depends on a co-registration of digitally reconstructed radiographs
(DRRs) that are generated from CT images and X-ray projections that are captured during the treatment
session. Changes in target position are relayed to the robotic arm, which adjusts pointing of the treatment
beam. The robotic arm moves through a sequence of positions (nodes).
At each node, a pair of images is obtained, the patient position is determined, and adjustments are made.

37. REGISTRATION
CONSULTATION WITH RADIATION
ONCOLOGIST
PRESCRIPTION OF DOSE
PLAN APPROVAL BY
ONCOLOGIST
COLLIMATOR FIXATION & LED
PLACEMENT FOR SYNCHRONY
COMMENCEMENT OF TREATMENT
TARGET CONTOURING
TREATMENT
PLANNING
PREMEDICATION
PATIENT SETUP IN TREATMENT
ROOM
CT SIMULATION
TREATMENT APPROVAL SIGN BY
ONCOLOGIST & PHYSICIST
IMMOBILISATION
PRE VERIFICATION IN
CONSOLE SYSTEM
ACHIEVE CRITERIA FOR
TREATMENT
DOCUMENTATION
MONITORING THE PATIENT THROUGHOUT
THE ENTIRE COURSE OF TREATMENT
CK WORKFLOW

38. Dilemma of patient setup
In spite of immobilization patients move
 External motion Voluntary
 Internal motion (Organ) Involuntary
So setup verification is necessary

39. Patient Safety Zone
Patient safety zone is used to determine the
boundaries with in which the patient must be
positioned for safe treatment .The patient safety
zone is set by the Proximity detection program
(PDP).
Proximity detection programs responsible for
monitoring movements of the treatment
manipulator and treatment couch to prevent
collisions.
Before treatment patient safety Zone is use to
determine the boundaries for positioning the
patient for safe treatment.

40. PDP-Proximity Detection Program
PDP-Zone is an important safety feature for patient treatment delivery
(small,medium,large-patient size )
Template Path Sets
 1 Path-full Path Set Templet
 Short path-a Subset Of The 1 Path Template For Faster Treatment
 Even Paths- Derived From The 1 Path Template And Divided Into 3 Even Paths Used
For Multi-collimator Treatments.
 Trigeminal Path-three Path Set Used For Trigeminal Treatments

41. Clinical Overview
 The developments of the Cyber Knife System have resulted in substantial
improvements in dose calculation accuracy, treatment plan optimality,
treatment delivery geometric accuracy, treatment time, and the range of
body sites that are technically accessible to treatment.
 Most recently, technical developments included in the Cyber Knife VSI
System have for the first time made practical the delivery of more
extended fractionation schemes (such as those common to IMRT).
 Although technical developments to the Cyber Knife System have
enhanced its targeting and tracking accuracy, simplified treatment
planning and improved the accuracy of dose calculation, and extended
the applicability of the system to lesions throughout the body.

42. Broad Clinical Applications of Cyberknife
Intracranial
Spine
Lung
Soft Tissues
Prostate
Arteriovenous malformation
• Bone metastases
• Brain tumors
 • Acoustic neuroma
 • Brain metastases
 • Gliomas
 • Astrocytoma
• Pituitary adenoma
• Kidney tumors
• Liver tumors
• Lung tumors
• Ocular/orbital tumors
• Prostate cancer
• Pancreatic cancer
• Spinal tumors
• Trigeminal neuralgia
Glioblastoma
multiforme
 Glioma
 Oligodendroglioma
 Meningioma

43. Tracking Modalities Reference to Applicable Target
Tracking Modalities Use fullness
6D-Skull tracking System Brain Tumor
Fuducial Tracking System Soft Tissue Target
Synchrony Tracking System Moving Soft Tissue Target
X-sight Spine Tracking System Spine Tumors
X-sight Lung Tracking System Moving Visible Lung Tumor
Lung Optimized Treatment
In Tempo Adaptive Imaging System
Lung Tumor without fiducial implantation.
Mostly Used to Adapt Prostate Cases

44. Tracking modalities versus Approaches

45. 6D- Skull Tracking System
 6D Skull tracking system used for intra-cranial lesions up to C2,Bony
anatomy of the skull is used as reference for tracking
 This tracking feature allows direct and non-invasive tracking of
Intracranial lesions
 Target tracking and motion compensation are accomplished by identifying
and tracking rigid Skull anatomy image intensity and brightness gradients
between the DRR and LIVE images
 The naming of this method as 6D because the corrections are made for the
3 translational motions and 3 rotational motions

46. 6D- Skull Tracking System cont.
6D Skull Tracking System Features
Tracking Mode Direct Tracking Intracranial Lesions without
the use of fiducials.
User Accessible Features Brightness Window (%) Enabled/Disabled
Gradient Window (%) Enabled/Disabled

47. Fiducial tracking system
The fiducial tracking system enables tracking extracranial tumors by tracking
implanted fiducial markers and correlates fiducial location in reference DRR
images with live x-ray images to extract fiducial location.
For soft tissue targets not fixed relative to skull/spine e.g. Prostate,
Pancreas, Liver, Lung ( X-sight unsuitable)
 Cylindrical gold seeds 0.8-1.2mm diameter, 3-6mm length
 3-5 markers spaced at least 1cm apart, 4-7 days for migration to settle
 Image registration based on alignment of these known DRR positions with the
marker locations extracted from treatment X-ray images.
The parameter Rigid body distance threshold in this system will give the maximum deviation of
the fiducial between DRR and the x ray image.

48. Fiducial tracking system cont.
General Minimum 3 fiducials required for accurate
target tracking including translation and
rotation movement.
Output to User  Fiducials Location(s)
 Probability measure value for
extracted fiducial combination
User Accesseable Features Rigid Body distance Threshold
Fiducial spacing Threshold
Colllinearity Threshold
 Fiducial pattern is recognized by the Cyberknife imaging system. Marker locations in the
Live X-ray images are compared to expected locations. The robotic couch automatically
repositions the patient
 The Cyberknife makes 6D (X,Y,Z; α, θ, φ) corrections to beam targeting using a rigid
transformation algorithm
 Live X-ray images taken during the treatment allows for semi-continuous monitoring of
intra-fraction motion (when not using Synchrony)

49. Fiducial tracking system cont
3 or more fiducial markers are placed inside the tumor with adequate separation

50. Interfraction and intrafraction Motion management for the floating targets
 Minimization of the CTV-to-PTV margin made possible by high accuracy of
treatment beam alignment and delivery
 Achieved through the combination of an X-ray image guidance system,
which enables frameless stereotactic targeting for all body sites
 A Robotic manipulator enables each beam to be aligned to the target volume
rather than moving the patient to align the target volume to each beam; and
continual image guidance and alignment correction throughout every
treatment fraction, such that there is no dependence on an absence of intra-
fraction motion
 Variable collimation, enabling multiple field sizes to be combined within each
treatment such that a complex dose distribution can be constructed from a set
of independently targeted and sized pencil beams.
Floating Tumor Target

51. Synchrony Respiratory Tracking System
X-ray images required for building the correlation
model between external chest wall motion and internal
target motion may be acquired manually, in a User
Defined sequence or by using the fully Automatic
functionality available.
The system automatically determines the best
correlation model type to be utilized for the particular
treatment by choosing the model type that minimizes
overall correlation error.
Synchrony’s Benefits:
 Patient breathes normally
 Lesion tracked throughout treatment
 Sub-millimeter tracking accuracy
 Minimal irradiation of healthy tissue
SYNCHRONY
JACKET WITH
LED MARKERS
SYNCHRONY
CAMERA

52. Synchrony Respiratory Tracking System Cont.
Real time tracking for tumors that move with Respiration
 No need for breath-holding, beam is dynamic throughout treatment
 Tumor position determined at multiple discrete time points by acquiring orthogonal X-ray images
 A correlation model is generated by fitting the tumor positions at different phases of breathing
cycle to simultaneous external marker position
The Synchrony Respiratory Tracking System continuously synchronizes treatment beam delivery to
the motion of a target that is moving with respiration
The system operates by creating a correlation model between the patient’s breathing pattern,
monitored in real-time, and the location of the target at various points in the respiration cycle.
The location of the target is determined by using X-ray imaging to visualize the lesion or internal
markers (fiducials), while the breathing pattern is tracked and monitored using external markers
(LED-based, fiber optic tracking markers) in real-time

53. Synchrony Respiratory Tracking System cont.
How it Works Basically:-
Prior to treatment start: creation of dynamic correlation model
This process repeats throughout the treatment, updating and correcting
beam delivery based upon the patient’s current breathing pattern
Imaging system takes positions of fiducials at
discrete points of time
Markers are monitored in real time by a
camera system

54. X-Sight Spine Tracking system
The X- Sight Spine Tracking System works by Computing the
Displacement of the Skeletal Structures with in the Patient
body.
The structures to be Tracked are Predetermined During the
Treatment.
The Tracking System Computes target displacement of nodes
of the ROI in the Live X-ray Images relative to the nodes in
the DRR Images.

55. X-Sight Spine Tracking system cont.
 Automatically locates and
tracks tumors along the Spine
 Eliminates the need for
surgical implantation of radiographic markers
 Facilitates faster, less complex treatments
An alternative that eliminates
risk for patients
• Sub-millimeter accuracy with
non-rigid registration
• Utilizes the bony anatomy of
the spine:
– Cervical
– Thoracic
– Lumber
– Sacrum
Based on high contrast bone information with image processing filters
• Tumors in spine, near the spine
• ROI: Vertebra of interest+2 adjacent vertebra

56. X-Sight Spine Tracking system features
 dxAB (mm) threshold
 False Nodes (%) threshold
 drAB (deg) threshold
 False Nodes A (%)
 False Nodes B (%)

57. X-sight Lung Tracking system
Fiducial-less lung tumor tracking
Tracking based on imaging of the lesion directly
Patient Selection
Target > 15 mm in each axis Peripherally located
Not obstructed by skeletal structures
Tracking volume is contoured for a visual reference.
Synchrony used for respiratory tracking
Global alignment> spine alignment centre>tumor treatment centre.
Direct tumor tracking is performed by matching image intensity
pattern of the tumor region in the DRRs to the corresponding region
in the treatment x-ray images.
Image intensity pattern-> T>15mm diameter, located in peripheral, apex lung regions

58. X-sight Lung Tracking system cont.
 Fiducial-less lung tumor tracking Tracking based on imaging
of the lesion directly
 Patient Selection
Target > 15 mm in each axis Peripherally located Not obstructed
by skeletal structures
 Tracking volume is contoured for a visual reference
 Synchrony used for respiratory
tracking
Initial patient alignment with X-sight spine
 “Go to X-sight Lung” Robo couch moves to align to target
 Visually confirm that the system truly detects lesion
 Build a Synchrony respiratory correlation model
 Begin Treatment
 Cyberknife adjusts beam targeting during treatment based on
Synchrony and intra-fraction images

59. Lung Optimized treatment
Treating lung SBRT patient with a non-invasive treatment option, regardless of tumor location.
Simulation and comparison workflows, combined with unique tracking modes, allow the clinician to
select from multiple, non-invasive options.
Allows to track the the tumor without fiducial even it is only visible on one of the Live X-ray images,
Lung optimized treatment includes a simulation application and two tracking modes:
1 View Lung tracking and 0 View Lung tracking
These two tracking methods are the true supplement for the fiducial free capability of X-sight Lung regardless
the location of the tumors.

60. Lung Optimized treatment cont.
 Non invasive X-sight Lung
Tracking or 2 view tracking when
the target is clearly visible by the
both the X-ray cameras
 Non-Invasive 1 view tracking when
the treatment target is clearly visible
and can be tracked in only 1 X-ray
projection
 O View Lung tracking or X-sight
spine tracking when the target is not
visible in either x-ray projections
resulting the need to track the bony
anatomy

61. Lung Optimized treatment cont.
X-Sight Lung Tracking Radiosurgical Margins 1 View Tracking
ITV expantion in Non Tracked Direction
0- View tracking
ITV Expansion In all Direction

62. In Tempo Adaptive Imaging System
 Intelligent, adaptive imaging system designed from the ground up to address the
unique challenges of prostate tracking resulting from random and excessive target
motion
 InTempo Adaptive Imaging System Tracking random motion of the prostate represents
one of the most significant challenges in the accurate delivery of radiosurgery
 This System recognizes that the prostate often moves during treatment delivery. With
the InTempo Adaptive Imaging System
 The Cyber Knife System not only tracks intra-fraction prostate motion, but actually
adapts imaging and treatment delivery based on how much and how fast the prostate
moves.

63. In Tempo Adaptive Imaging System Cont.
Tracking Benefits:
 Better target tracking and delivery compensation for target shifts
 Improved tracking of the prostate under both slow drift movement and
sporadic motion
 Intelligent, adaptive and on-the-fly tools available to the user in daily clinical
practice Integrated checks to assist in patient
Image Age
The InTempo System makes use of the Image Age parameter to control treatment
beam delivery. Image Age is the time elapsed since the most recent image
acquisition.
Adaptive Imaging
With the InTempo System, the user may optionally allow the system to trigger
adaptive imaging in the event that the assessed rate of target motion is greater
than a user-defined threshold. Breach of this threshold causes the system to
automatically reduce the maximum allowable image age.

64. CT Scan Imaging Protocol of Cyber knife System
The patient positioning during the CT scanning should be the same as the
patient position that will be used to treat the patient, immobilization devices
used in the CT scan same should replicate in treatment also.
Basic parameters of CT scanning as follows…
 Axial or spiral 1 to 1 pitch.
 IV contrast may only used for secondary CT image studies.
 Kvp=120,mAs>400.
 No more then 1.5mm slice thickness.
 Field of view(FOV) must include the entire circumference of the patient,
must be a square image acquisition, must include immobilization devices.

65. Emergency Procedure
Emergency stop procedure.
 The energy stop button does not work.
 Emergency power off procedure.
 Power failure.
 The treatment couch does not work properly.
 The manipulator arm moves in an unexpectable way.
The emergency power off (EPO) that removes power from all
non computer
equipment when activated.

66. Dose Calculation
Ray Tracing Dose Calculation
The ray-tracing dose calculation algorithm uses three system-specific beam description tables
comprised of data measured using a water phantom.
• OF value for each collimator is normalized to the value of the OF for the 60 mm collimator at
800 mm SAD and
15mm depth, which is defined to be 1.0
Tissue density corrections can be applied using the effective path length algorithm. Surface
obliquity can be corrected using a geometric ray tracing algorithm
Calibration Conditions:
 d-max = 15 mm
 800 SAD
 60 mm Fixed Collimator

67. Cyberknife Dose Distribution
The robotic design of the Cyber Knife System seamlessly delivers non-
coplanar, non-isocentric and isocentric beams
Wide range of available beam angles sculpts conformal dose distributions
and enables safe and effective treatments regardless of the disease
complexity and location
Generates the sharp dose gradient required for lesions close to critical
structures and minimizes dose delivered to normal tissues

68. Cyberknife Dose Distribution
Acoustic Neuroma
 Treatment Mode: Cyberknife SRS
 Rx: 13Gy/#
Brain Mets
 Treatment Mode: Cyberknife SRS
 Rx: 20 Gy/#

69. Cyberknife Dose Distribution
Meningioma
 Treatment Mode: Cyberknife SRS
 Rx: 25Gy/5#
Trigeminal Neuralgia
 Treatment Mode: Cyberknife SRS
 Rx: 45Gy/# (Max: 80 Gy)

70. Cyberknife Dose Distribution
Lung SBRT Dose Distribution

71. PTV Margin in Respiratory Motion
Great Battle for margin – CBDRT  2DCRT 5cm
IMRT 5-8mm
IGRT – 3-5mm
CK <=3mm
Proton IMPT  High RBE border/margin – bragg peak
Cyber Knife users have reported using margins
as large as 8 mm (Ref. 17)
as small as 2 mm (Ref. 6); (F. Casamassima et al, 2006)
common margins are 3–5 mm. (Ref: 1,7,8)
Correlation and prediction uncertainties in the Cyber Knife Synchrony respiratory tracking
system. Eric W. Pepin et al Med. Phys. 38 (7), July 2011
We go by size, location, Sensitivity: Gradient  great saviour

72. Cyberknife SBRT/SABR Quality
Cyberknife has the advantage of adapting to the full 3D motion of the tumor.
There will be 200 ms delay between acquisition of tumor coordinates and repositioning of the linear
accelerator.
In CK, system coupled through a real-time control loop to an imaging system that monitors the tumor
position and directs the repositioning of the linear accelerator.
System uses a specially designed composite imaging/dosimetry phantom to check the geometrical
relationship between tracking system and beam-delivery systems.
The management of respiratory motion in radiation oncology report of AAPM Task Group
76a.Paul J. Keallb_ et al

73. Daily QA for RTT’s
Mechanical QA-To evaluate the geometrical accuracy & functionality of
treatment unit.
Linac & x ray tube should be done prior to the treatment.
X-ray tube warm up should be done before the treatment if the machine was
idle for more than two hours.
PROCEDURE ACTION LEVEL
Door interlock - functional
Radiation room monitor - functional
Audiovisual monitor - functional
Lasers - 2mm

74. Disadvantages & Unexplored
Long session – Need to Compensate for low dose per hour
Not continuous tracking…predefined beams every 3-5….continuous
drift.. Next speaker
Differential concentric – Sieve therapy – HDR Brachytherapy like
Growing border
Stem cell concentric
Hypoxic cell concentric
Anoxic concentric

75. Frequently Asking Questions
1 What is Cyberknife? Robotic Radiosurgery System (Worlds No 1)
2 For What It is ? Whole Body Stereotactic Radiosurgery Solution
3 What It Contains ? Robot/Linac/X-Ray/Imager/Couch
4 What is the mould room
process?
Different from Usual
5 How to take the CT for this Standard Technique
6 Do we require 4D-CT No
7 Is it Offers real time Tracking Yes
8 How Many Tracking Tools
Available
6 Modes
9 Is there 3D Imaging ? No
10 Is there any
Isocenter/Reference
Yes For Dosimetry Purpose
11 Can We Use Fiducials? Yes But not necessary
12 What is the Maximum Field Sizes 60mm
13 Fixed Field Sizes or ?? Yes
14 Is there use of MLC? IRIS

76. Frequently Asking Questions
15 What kind of cases we can Perform? Both Intracranial And Extra Cranial Tumors
16What is the Dose Rate? 1000 cGy /Min
17Is there any Record and Verify system? NO
18 6D Couch Yes
19 Treatment Time Duration Min 40 Min- 2 hr.
20 How to ensure the PDP With Safety Position Check Tool
21 What Is the Home Position Of the Robot Perch Position
22 Is it a Non-Coplanar Treatment? Yes
23 No Of Fix Collimator Available? 12
24 Fraction Interruption Procedure Track again with Fresh Kv Image

77. Discussion & Conclusions
Cyber Knife Radiosurgery is an ideal machine for both cranial & extracranial radiosurgery
Appropriate patient selection is the most important factor
Cyber Knife is safe and patient friendly radiotherapy delivery system
Short course, precise, high dose RT may be beneficial in few indications

78. THANK YOU FOR KIND ATTENTION