gms | German Medical Science

Purpose: To observe detailed changes of neurosensory retinal structure after Anti-VEGF upload in age-related macular degeneration (AMD) using spectral domain optical coherence tomography (SD-OCT).

Material and methods: The retinal structure was observed in 61 patients using the Spectralis-OCT (Heidelberg engineering, Germany) before and one months after third Ranibizumab injection (upload phase). The main focus of attention was subjectively laid on the amount and behaviour of the numerous small dense particles (SDP) frequently observable within the outer and inner neurosensory layers in eyes suffering from neovascular AMD. For statistical analysis the Spearmans Rho correlations were used (SPSS for Windows 16.0).

Results: In all eyes SDPs of various amounts were seen within the neurosensory layer of the foveal and parafoveal area. In 54% the amount of SDP became significantly less after therapy (stable 41%, more 5%). The SDP reduction was positively correlated with the reduction of retinal pathology in the OCT (p=0.000), with central foveal thickness (p=0.040) and with the increase of best corrected visual acuity (BCVA; p=0.006). The baseline amount of SDPs was also positively correlated with the increase of BCVA (p=0.005).

Conclusion: The origin of SDP observable in SD-OCT is unknown but might represent migrating RPE cells or leucocytes indicating a certain status of retinal inflammation. SDP amount is predominantly reduced after Ranibizumab upload therapy and positively correlated to BCVA. Moreover, an initial larger number of SDPs might indicate a higher grade of inflammation but better results of Ranibizumab therapy were achieved. Thus, the amount of SDPs before treatment might be a predictive factor for therapy outcome.