1. 당뇨황반부종에서의 레이저 치료
의정부 성모병원 안과 양지욱

2. Laser in diabetic macular edema
Focal/grid laser has been the mainstay of treatment for diabetic macular edema(DME) until the recent findings of the Diabetic Retinopathy Clinical Research (DRCR) network, which suggested that intravitreal ranibizumab with prompt or deferred laser is more effective...
Diabetic Retinopathy Clinical Research Network. Randomized trial evaluating ranibizumab plus prompt or deferred laser or triamcinolone plus prompt laser for diabetic macular edema. Ophthalmology 2010;117(6):1064 –1077.

3. When treating diabetic macular edema...
Focal laser photocoagulation
Grid laser photocoagulation
In ETDRS, after 3-years of F/U, 24% of the control group experiences moderate visual loss compared with 12% of the treated eyes.
Focal/grid photocoagulation reduced the risk of moderate visual acuity loss for all eyes with diabetic macular edema by about 50 %.

4. Focal laser photocoagulation
Focal macular edema -
Direct treatment of all leaking microaneurysms in the edematous retina between 500 and 3000 µm from the center of the macula

5. Focal laser photocoagulation
Wavelength – green or yellow
Spot size - 50 ~ 100 µm
Exposure time sec
Power – initially quite low and slowly increased to
obtain either whitening or darkening of the
microaneurysm with minimal power

6. Laser wave length - Laser absorption
Why green or yellow wavelength?!
Hemoglobin
: strong absorption in
violet(420 nm),
green(540, 580 nm)
Xanthophyll
: peaks in the blue(460 nm)

7. Laser wave length - Laser absorption
Power??
- whitening or darkening of the microaneurysm
with minimal power
Usually, a microaneurysm or area of diffuse edema that is slightly distant from the fovea is treated first
The power is increased in 10 mW increments until a desired end-point
It is important not to place intense burns close to the fovea !!

8. 2) Focal macular treatment
Focal photocoagulation in
focal ME with diabetic retinopathy

9. 2) Focal macular treatment
시술직후
시술전
시술후 4주
시술후 4개월

10. 2) Focal macular treatment
Focal photocoagulation in
focal ME with diabetic retinopathy

11. 2) Focal macular treatment
시술직후
시술후 2주
시술전
시술전
치료 효과를 판단하는 기간이
laser는 triamcinolone이나 anti-VEGF intravitreal injection보다
오래 걸린다...
시술후 6개월

12. Grid laser photocoagulation
Diffuse macular edema -
Primarily used for areas of diffuse leakage
with no identifiable focal areas of leakage
Spot size - 50 ~ 200 µm
Exposure time sec
Power – light intensity burns
Producing a grid of equally spaced burns more than one burn-width apart

13. 2) Focal macular treatment
Grid laser in CSME with diabetic retinopathy
시술후 4개월

14. Modified grid laser photocoagulation
Direct treatment of visible microaneurysms +
Grid pattern of treatment to fill-in the rest of the edema

15. Visual outcome Less favorable visual outcome 1) Diffuse macular edema
2) Macular ischemia in addition to edema
3) Old lipid exudate involving the center macular edema
Better favorable visual outcome
1) Focal macular edema
– round lipid ring threatening the macular center

16. Benefits of laser treatment for CSME
Mainly manifested by a reduction of the rate of visual loss
Very few patients experience significant visual improvement

17. Complications Sx) Immediate or late visual acuity loss Scotoma
Fd) Choroidal neovascularizaion
Preretinal or subretinal fibrosis
Laser scar expansion
Exacerbation of preexisting macular edema
Tractional retinal detachment

18. Complications
Initial treatment closer than 500 µm to the foveal center is avoided
Excessive treatment should be avoided
- can lead to extensive chorioretinal atrophy that can spread and impair central vision
- Heavy focal burns may induce CNV

19. Thank you for your attention!
3년전 diabetic macular edema로 FRP(OS)
Thank you for your attention!
FRP후 3년
FRP후 4년
FRP후 5년
FRP후 9년

20. Complications – laser scar expansion
FRP후 3년
FRP후 9년

21. Modified ETDRS laser photocoagulation protocol
Focal photocoagulation
Wavelength – green or yellow
Spot size – 50 µm
Exposure time ~ 0.1 sec
Power – Change in microaneurysm color – not requires, but at least a mild grey-white burn should be evident beneath all microaneurysms
Writing Committee for the Diabetic Retinopathy Clinical Research Network, Fong DS, Strauber SF, Aiello LP, et al. Comparison of the modified Early Treatment Diabetic Retinopathy Study and mild macular grid laser photocoagulation strategies for diabetic macular edema. Arch Ophthalmol. 2007;125:469–480.ㅇㅀ

22. Modified ETDRS laser photocoagulation
Grid photocoagulation
Wavelength – green or yellow
Spot size – 50 µm
Exposure time ~ 0.1 sec
Burn intensity – Barely visible (light gray)
2 visible burn widths apart
No burns are placed within 500 µm of the disc & fovea center

23. SDM photocoagulation 치료직후
Subthreshold diode-laser micropulse photocoagulation
Grid photocoagulation
mETDRS protocol
SDM photocoagulation 치료직후

24. mETDRS
photocoagulation
SDM
Photocoagulation

25. mETDRS photocoagulation
SDM Photocoagulation

26. Laser in diabetic macular edema
Does laser still have a role in the management of diabetic macular edema??
1) Focal macular edema
- focal laser may still be a good treatment option
2) Patients who cannot tolerate or comply with the need for monthly visits and injections
3) Poor response to anti-VEGF
4) Decrease the frequency of injection??