Appearance of Photocoagulation Laser Burns One Week After Treatment
One week after photocoagulation treatment, laser burns on the retina appear as well-defined gray-white lesions with early healing changes at the junction of inner and outer segments of photoreceptors and apical retinal pigment epithelium. 1
Morphological Features at One Week Post-Treatment
Visible Characteristics
- Gray-white lesions with defined borders
- Early healing response beginning to manifest
- Structural changes primarily at the level of:
- Junction of inner and outer segments of photoreceptors (JI/OSP)
- Apical retinal pigment epithelium (RPE) 2
Size and Evolution
- 20-millisecond burns show approximately 35% reduction in size by 4 weeks, with healing changes beginning to appear at the one-week mark 2
- 100-millisecond burns maintain more stable size with less reduction over time due to greater thermal damage 2
- The greatest linear diameter (GLD) of burns begins to change during the first weeks post-treatment 2
Imaging Findings
Optical Coherence Tomography (OCT)
- Burns appear as columnar foci of hyperreflectivity in the outer retina
- Visible disruption at the junction of inner/outer photoreceptor segments
- Defects visible at the level of the retinal pigment epithelium
- Evidence of Bruch's membrane disruption where higher energy was applied 2
Fundus Autofluorescence
- Increased autofluorescence corresponding to the burn areas
- Autofluorescence intensity correlates with the pulse duration used during treatment 2
Clinical Considerations and Complications
Early Complications to Monitor
- Macular edema may be present, especially when treating branch retinal vein occlusions 3
- Risk of subretinal hemorrhage in the first month after treatment, particularly in vascular conditions 4
- Early signs of choroidal neovascularization may begin to appear as early as 2 weeks post-treatment in areas where Bruch's membrane was ruptured 5
Healing Process
- The healing response is localized primarily to the junction of inner/outer photoreceptor segments and apical RPE 2
- Short-duration burns (20ms) show more significant healing and size reduction compared to longer-duration burns (100ms) 2
- Thermal blooming and collateral damage are more evident with higher-fluence burns 2
Follow-up Recommendations
After photocoagulation treatment, follow-up should include:
- Visual acuity assessment
- Dilated fundus examination
- OCT imaging to evaluate macular edema and burn morphology
- Careful examination for early complications such as choroidal neovascularization or subretinal hemorrhage 3
Recognizing the normal appearance of photocoagulation burns at one week is essential to distinguish expected healing changes from complications requiring intervention. The progressive reduction in burn size over the following weeks represents a normal healing response rather than a complication.