Purpose
Investigating the presence of reliable prognostic parameters to answer to 2 key questions at the beginning of therapy: a. what is the functional outcome going to be? b. how long will the effect of every injection last?
Methods
We retrospectively reviewed the records of all patients who received dexamethasone intravitreal implants (Ozurdex, Allergan) for macular edema secondary to RVO in the last 18 months. We looked for all parameters that could have been of prognostic value in terms of visual recovery and duration of DEX effects: beginning of symptoms, BCVA, angiographic parameters (intraretinal hemorragies/cotton wool spots, FAZ, peripheral ischemia) and OCT findings (foveal/ONL thickness, IS-OS integrity, neurosensory det.), and also registered if these parameters were gradable or not at T0. At T0 and than monthly all patients received a complete examination with OCT, and FA at T0 and every 4 months. Reinjection was performed at the worsening of OCT parameters compared to T1. In patients with >1 DEX injection, we registered duration of effects and consistence of anatomical/functional results of each injection.
Results
Thirty three consecutive patients for a total of 76 injections were reviewed. Nine patients received 1 injection, 12 received 2 injections and 12 had 3 or more injections. Among the 9 patients who received just one injection, 5 with a f/u of 8-14 M had a complete and stable recovery. Angiographic and OCT parameters resulted “not gradable” in more than 50% of eyes at T0. In terms of visual recovery, none of the measured parameters was significantly correlated with VA improvement ≥ of 15 letters, or with the duration of DEX effects. Apart from the 5 eyes that never needed a second injection, DEX effects lasted 12-22 weeks (mean 17 weeks). Functional results and duration of the first injection remained unchanged for every patient at the following injections.
Conclusions
In our small case series, we didn’t find any functional or anatomical value that has a consistent prognostic value before the beginning of therapy. The only reliable and predictive parameter is the result of the first injection, that seems to remain stable during follow up and can be used for tailoring the follow up schedule to the single patient. Stable results of the first DEX injection >8M have a high probability to be definitive, possibly due to the positive natural course of the disease.
Keywords: 749 vascular occlusion/vascular occlusive disease •
505 edema •
561 injection