Robotic radiosurgery treatment is an excellent treatment option for eye tumours. This presentation explains in detail the application of CyberKinfe as a treatment option.

1. Robotic Radiosurgery Treatment for Eye Tumours
Debnarayan Dutta, MD
Head, Department of Radiation Oncology
Amrita Institute of Medical Science, Kochi

2. 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
Ideal for moving targets

3. Robotic Radiosurgery: Common Indications
CNS lesions

4. Robotic Radiosurgery: Common Indications
Extra-cranial sites

5. PTV Margin:1-4mm
PTV margin- 1mm PTV margin- 3 mm
Margin due to- 1) set-up error; 2) Image distortion, 3) Fusion error, 4) Mechanical uncertainty

6. Eye tumours: USUALLY <2mm
1. Choroidal melanoma
2. Choroidal haemangioma
3. Choroidal metastasis
4. Intra-orbital lymphomas
5. Optic nerve glioma/ meningioma
Present early- vision disturbance
Diagnosed with Fundoscopy & thin slice imaging

7. Challenges to treat eye Tumours/ Lesions
- Size: 2-4 mm: Localization is issue
- Movement every second- Need ‘Real time’ tracking
- ‘Bells’ phenomenon- rotation of eye ball on closure of the
eye- Need to ‘Fix’ eye prior to treatment
- Need accurate imaging- to localize lesion
- Issues with restriction of movement
- Minimal image distortion
- Planning treatment has challenges
- Vision is as important as life
- Issues with visual loss/ impairment after RT
- Small lesions: Close to Optic Disc / Fovea
Early vision impairment
Candidate for SRS
Optic nerve close- Need caution
- Larger lesion: peripehery
Usually present late- Surgery

8. In choroid melanoma (n~800 pts) with proton beam therapy & similar
verification local control rate is >90% at 10 yrs
Mammar H, IJROBP 2010
Evidence with RT in eye lesions
100Gy equivalent dose in hypofractionated regimen (6-8 sittings)
60Gy/3# with CyberKnife treatment with block
Lille & Nice Centre; Munich CyberKnife Centre
RT is an established indication for eye tumours
Bondiue, Latigo, Muacevic et al

9. Verification System: Proton beam therapy
Mammar H, IJROBP 2010(Courtesy: Dr Hammid Mammar; Nice; France)

10. Verification System: Proton beam therapy
Mammar H, IJROBP 2010(Courtesy: Prof Hammid Mammar; Nice; France)
NEED ‘Real’ time tracking to treat eye lesions

11. Treatment process: Work flow
Similar principle is followed in Robotic radiosurgery treatment
1. Selection of cases
Choroidal melanoma
Choroidal haemangioma
Orbital lymphoma
Optic nerve sheath meningioma

12. Treatment process: Work flow
2. Pre-treatment evaluation-
- Imaging- MRI scan/ Thin slice CT scan
- Fundoscopy
- Perimetry/ acuity of vision
- VEP
- Visual field mapping
- Angiography
- USG
Follow up: Repeat after 6 months, 1 yr then yrly

13. Visual field mapping
Treatment process: Work flow

14. Treatment process: Work flow
Treatment execution: TIME BOUND in 3 hr
Thermoplastic Mask
Retrobulbar block-
Lignocaine/ Bupevacaine
4 quadrant block
Block starts in 15 min- stay for 3 hrs
Imaging with block
MRI scan- T1Contract, T2 Flair with zero gap
CT scan- 0.6-1mm thin slice with contrast
Image fusion/contour with block-
After fusion of images contouring done
Radiologist & Opthalmologist opinion mandatory
Inputs from Fundoscopy, USG taken
Planning-
5 mm collimator used
No of nodes/ beamlets considered
Treatment time considered

15. Treatment process: Work flow
Fixation of the eye: Retrobulbar block
Lignocaine+Bupevacaine
Four Corner Block
Duration- 3 hr

16. Treatment process: Work flow
Imaging with Block

17. Treatment process: Work flow
Image Fusion, planning

18. Treatment process: Work flow
Treatment execution
- Positioned with mask
- Verification done
- Care of Eye- Eye drop
- Shielding eye during waiting / treatment
- Observe effectiveness of block every 15 min

19. Treatment process: Work flow
Treatment execution

20. Treatment process: Work flow
Set-up & Obervation

21. Treatment process: Work flow
Verification

22. Dosage schedule
Choroidal melanoma: Small vol (<5mm)- 20Gy/1#
large Vol(5-10mm)- 60Gy/3#
Choroidal haemangioma: Small vol (<5mm)- 8Gy/1#
large Vol(5-10mm)- 15-18Gy/3#
Intraorbital lymphoma: 21-24Gy/3#
Choroidal metastasis: 8-10Gy/1#

23. Treatment process: Work flow
Multiple fraction treatment
Day 2
Repeat the process
Block/ Imaging/ contour
Match with previous day plan
If matched- Treated
NOT matched- Re-plan

24. Results
Type No Age Remarks
Choroidal Melanoma 2 25, 37 1 pt on FU, FU: 49 mo
Stable disease
Vision- preserved
Choroidal metastasis 2 49, 52 Ca Breast primary
Both vision loss >1 mo
No vision improvement at 3 month post CK
Choroidal
Haemangioma
7 6, 8, 12,
7, 15,
32, 35,
Stuge Weber Syndrome 5 pts
Longest FU: 60 months
All responded to treatment
Bilateral Intra-orbital
Lymphoma
4 45, 53,
60, 78
More involved Eye: 3DCRT
Less Involved: CK 21-24Gy/3#
All responded to treatment
Significant Vision improvement
Longest FU: 65 months
Optic Nr glioma/
Meningioma
17 Median
37
Significant regression of mass in majority

25. 32 yr Female from Bangladesh
C/O: progressive dimness of vision of right eye.
320 slice CT scan: 2 mm nodule at the retina
(fovea)
CK plan: 20Gy/1#; prescription at 70% isodose
Follow up: At 49 months, stable disease. No
deterioration of visual acuity
Choroidal melanoma

26. Follow up: 49 months
Stable disease
Choroidal melanoma
Planning: 20Gy/1#

27. Choroidal haemangioma
Associated with Sturge Weber Syn & VHL
Facts:
Usually patient have Retinal detachment
because of mostly exudate from
haemngioma
Post-CK, regression of haemangioma,
reduction of secretion from haemangioma
Improvement of Retinal detachment
Significant improvement of vision
Reduction of Glocuma

28. 7 yr old male child with Sturge Weber Syndrome
had glaucoma and vision loss of right eye (only
PL/PR) and progressive dimness of vision of left
eye (6/36)
320 slice CT scan & MRI scan: Haemangioma
left eye with retinal detachment
CK plan: 7Gy/1#; prescription at 85% isodose
Follow up: At 60 months, complete resolution
of haemangioma and resorption of retinal
detachment. At 2 months post CK, visual acuity
improved to 6/18 and maintained till last follow
up (60 month).
Choroidal haemangioma (6Yr/M)
Planning: 8Gy/1#

29. Choroidal haemangioma (6yr/M)
60 month Follow up

30. Choroidal haemangioma (12Yr/Male)
Planning:15Gy/3#

31. Choroidal haemangioma (35Yr/Female)
Planning:15Gy/3#

32. Choroidal haemangioma (8Yr/Male)
Planning:18Gy/3#

33. Bilateral Intra-orbital Lymphoma
- Bilateral Intraorbital Lymphoma: Low grade DLBCL
- Usually confined to orbit only
- Stage: IE
- Treatment: Radiation therapy Only
- Usually presents with Bilateral Vision loss
- Usually more involved eye have vitrious seedlings
- Usually, more involved eye: whole orbit treatment: 3DCRT
45Gy/25#
- More preserved, only choroidal involved eye: focal RT: 21-24Gy/3#
- Same patient have a ‘Control’
- One eye Conv RT Vs less involved Eye: High precision RT

34. Bilateral Intra-orbital Lymphoma
Results
N
o
Age Disease Dose Pre-RT Vision Pre-RT
Vision
Image
response
FU (mo) Event
1 45/F Rt Eye- Choroid only
disease
Lt Eye- Vitrious seeding
Rt Eye- 24Gy/3#CK
Lt Eye- 40Gy/16#
3DCRT
Rt Eye-
Lt Eye-
Rt Eye- NA
Lt Eye-NA
Good Parital
response
24 CR at 2 yr
2 53/M Rt Eye- Choroid only
disease
Lt Eye- Vitrious seeding
Rt Eye- 24Gy/3#CK
Rt Eye- 45Gy/25#
3DCRT
Rt Eye-
Lt Eye-
Rt Eye- NA
Lt Eye-NA
CR 35 CR at last
FU
3 60/M Lt Eye- Choroid only
disease
Rt Eye- Vitrious
seeding
Lt Eye- 24Gy/3#CK
Rt Eye- 35Gy/14#
3DCRT
Rt Eye- PL/PR
Lt Eye- 6/36
Rt Eye-6/18
Lt Eye-6/6
CR 65 CR & on FU
4 78/M Rt Eye- Choroid only
disease
Lt Eye- Vitrious seeding
Rt Eye- 24Gy/3#CK
Lt Eye- 40Gy/16#
3DCRT
Rt Eye-
Lt Eye-
Rt Eye-NA
Lt Eye-NA
CR 26 Lymphnode
at 26 mo, on
CT
Local CR

35. 60 yr old doctor from Kolkata with progressive loss of vision of
both eyes. Right eye only PL/PR and left eye 6/36 vision
MRI scan and PET scan: Retro-orbital mass left eye
suggestive of lymphoma
Biopsy: Marginal zone lymphoma (Low grade)
CK plan: 21Gy/3#/3 days; prescription at 80% isodose to left
eye and 35Gy/14#, 3DCRT to right eye.
Follow up:
At 26 mo, PET scan-complete resolution of mass & resorption
of retinal detachment.
Visual acuity of left eye at last FU 6/6 & right eye 6/18. There
was no appreciable enopthalmos and no dryness of eye.
At 65 mo FU, stable condition (CR)
Bilateral Intra-orbital Lymphoma
Results

36. Pre-RT
Yr-2010
RT Eye-
Target- entire orbit
35Gy/14# 3DCRT
LT Eye-
Target- Only PET uptake region
24Gy/3# CK

37. Bilateral Intra-orbital Lymphoma
Results

38. Post-RT: 60 mo
2015

39. Bilateral Intra-orbital Lymphoma
Fundoscopy: Pre-RT

40. Bilateral Intra-orbital Lymphoma
Fundoscopy: Post-RT 60 month
Improvement in Retinal detachment

41. Toxicity
- Mostly well tolerated, usually no major acute complications
- Time consuming & exhaustive treatment, need patient motivation
- Vision impairment immediate CK period, resolved after 6 months
- Due to optic neuritis- treated with low dose steroid for 3 months
- 2 haemangioma pts documented transient optic neuritis post-CK period (3
mo FU)
- Retinal detachment NOT resolved completely in all haemangioma patients.
Need long-term follow up to evaluate impact of fibrosis on vision function
- Issues with retrobulbar block

42. Toxicity: Retobulbar block
One pt had complications due to Retrobulbar block

43. Toxicity: Retrobulbar block
Recovered at 3 month follow up assessment

44. 1. Treatment of eye tumours with high precision radiation therapy such as
CyberKnife is possible with excellent reasonable long-term follow-up.
2. Choroidal haemagioma, Choroid melanoma and orbital low grade lymphomas are
safely and effectively treatable with fractionated radiosurgery.
3. CyberKnife is feasible organ and function preserving option for ophthalmological
conditions.
4. Early outcomes in selected indications in our cohort of patients are encouraging.
5. There is a need for a larger cohort of patient in our patient population.
Conclusions

45. Acknowledgements
Nice, France
Dr Hameed Marmar
Dr Bondiue
Oscar Lambart Centre, Lille, France
Dr Eric Latigue
Dr Xavier Mirabel
Munich CyberKnife Centre, Munich
Dr Alex Muacevic
Sankar Netralaya Hospital, Chennai
Dr Vikas Ketan
Dr Ambika
Dr Durgapoorna
Dr Prativa Mishra
Apollo Cancer Hospital, Chennai
All Colleagues & Physicists duttadeb07@gmail.com