Key Points
- Which lesions need continuation of anti-VEGF treatment? Until recently, the presence or absence of fluorescein leakage and
the angiographic appearance of the lesion were the main criteria for the decision to treat and re-treat the neovascular AMD
lesions using photodynamic therapy. Recently, there is a tendency to assess the activity of CNV lesions with only OCT without
performing FA after the initial assessment. Dr Ozdek believes there are other parameters which should be taken into consideration
and has devised an activity scoring system to define lesions by quantifying their activity to determine need for treatment.
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With the emergence of anti-VEGF treatment for neovascular age-related macular degeneration (AMD) lesions, it is becoming more
and more important to assess the activity of the lesion to decide on additional treatments. This is because of both economical
problems related to high cost of the treatment as well as injection and drug related complication risks. Nobody is sure about
when to stop treatment and when to treat. There are relatively few findings relating to fluorescein angiography (FA) and optical
coherence tomography (OCT) indicating an active neovascular AMD lesion. However, there is no clear criteria to define an
active lesion and to define the response of the lesion to the treatment. Here there are two ends of a spectrum:
Inactive
Figure 1: An inactive scarred lesion that does not need any treatment Ophthalmoscopy: No haemorrhage, well defined scar tissue,
Fundus FA: No late leakage Vision: Stable for a long time, AS: 4 NO NEED FOR TREATMENT
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- a totally fibrotic yellow scarring lesion
- without any haemorrhage around
- only late staining of the scar tissue in FA, and
- no subretinal or intraretinal fluid in OCT
- with stable vision for a long time does not need any treatment (Figure 1)
Active
Figure 2: A highly active lesion that definitely needs treatment. Ophthalmoscopy: Subretinal haemorrhage around the lesion,
no well defined scar tissue, Fundus FA: Significant late leakage Vision: Recent deterioration AS: 9 NEED TREATMENT
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- a choroidal neovascularization (CNV) lesion with subretinal haemorrhages all around
- significant late leakage in FA and
- a considerable subretinal or intraretinal fluid in OCT and deteriorating vision recently needs treatment with no doubt (Figure 2)
Table 1: Activity Scoring System (ASS).
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However, most of the lesions are in between the two ends of this spectrum, especially during the course of any treatment and
it may be difficult to decide if any further treatment is necessary or not. Here I suggest an activity scoring system (ASS),
which can easily be applied to all of the CNV lesions. We have been using this system for the last five years and modified
it several times to be as simple and user-friendly as possible (Table 1). The aim of ASS is to define the lesions by quantifying the activity to determine the need for treatment.
Activity scoring system
The proposed ASS is based on the well-known and widely used signs and findings of active CNV:
- Presence of subretinal or intraretinal fluid in OCT,
- Presence of haemorrhage associated with the lesion,
- FA staining pattern,
- Change in size of the lesion (lesion area in FA),
- Changes in objective (measured) visual acuity (VA); subjective vision (what the patient feels)
Apart from FA staining pattern, all of the other assessments are based on the changes in each parameter (same-baseline/increased/decreased)
and given a number to define the activity. At the end of the assessment, the numbers are totalled and an activity score is
obtained.
Activity scores (AS) can range between 0 and 14. We believe that a CNV lesion with AS of 6–7 or more requires treatment and
<6 does not. We are currently compiling a paper to more accurately determine the cut off AS to separate those lesions that
need treatment and those that do not.
