2. In Treatment of age related Macular
Degeneration Anti VEGF injections played
pivotal role since their discovery in mid
2000s.
Earlier treatments merely slowed the on going
visual loss, whereas with Anti VEGF injections,
one could expect visual improvement.
4. Clue taken from oncology
Uses a low energy X ray source
X ray is collimated to a narrow beam
I. Enables rapid dose fall off
II. Precise targeting
III. Minimum radiation scatter
During treatment, a vaccum coupled contact
are used to stabilise globe
Real time monitoring done
5. One year clinical trial, double blind
prospective study.
230 patients of neovascular wet AMD * 3
years, already receiving anti VEGF injections.
All received an initial dose of ranibizumab
and were randomised to receive 16Gy
radiation.
Single 26 min radiotherapy treatment was
given.
Patients were evaluated monthly *12months
6. After 1 year- Injections were reduced by
1/3rd with comparable visual acuity. Then
patients were returned to their original
drug schedule
After 2 years- Safety and efficacy data
were collected. Injections were reduced by
26%. Vision changes were similar.
After 3 years- Only safety data were
collected. No significant difference visual
outcome.
Radiation retinopathy- 33/122
18 regressed
14% wet amd
8% dry amd
7. Radiations are anti-angiogenic, anti-
inflammatory, anti-proliferative.
Doesn’t treat scar tissue.
Eyes with actively proliferative leisons,
producing fluid leakage are more likely to
respond.
Fibers grow centrifugaly, so fibers remain
proliferative at edges.
Lesions with diameter <4mm, and/or macular
volume >7.4mm^3 reqired fewer injections.
8. Radiation radiotherapy rare below 30 Gy.
Develops within 7-36 months.
Long term s/e like radiation radiotherapy and
microvasculopathy.
Simultaneous clinical trial of s/e was
conducted.
9. Over 3 yrs, 30 % patients receiving
radiations developed small localised
microvascular abnormality.
It didn’t modify visual outcome
significantly.
Few regressed themselves over time.
Radiation exposure is 10% of CT Head &
same as dental radiography.
Fractioning total dose reduces the risk
Radiation retinopathy is now treatable by
Anti VEGF drugs.
10. Most tolerated the treatment well and
were satisfied.
Decreasing injections was most imp
cause.
