Abstract
Purpose:
to explore long term retinal and choroidal changes, using enhanced depth imaging optical coherence tomography (EDI-OCT), and visual function changes after intravitreal ranibizumab 0.5 mg in patients with diabetic macular edema (DME)
Methods:
Consecutive patients with a diagnosis of DME were enrolled in this prospective, noncomparative case series and treated with repeated intravitreal injections of ranibizumab 0.5 mg. At baseline patients performed a complete eye examination including BCVA with ETDRS charts, slit lamp examination, IOP measurement, ophthalmoscopy, retinal and choroidal thickness measurement using enhanced depth imaging optical coherence tomography (EDI-OCT, Spectralis; Heidelberg Engineering GmbH, Heidelberg, Germany). All patients were treated with 3 injections of ranibizumab 0.5 mg 1 month apart till VA stabilization and retreated according to predefined criteria, based on VA and OCT, evaluated monthly for a period of up to 12 months.
Results:
23 DMO eyes of 23 patients with diabetes (14 male; 9 female, type 1: 4/23 and type 2: 19/23) with a mean age of 66.2±8.3 years were included in this analysis. Mean diabetes duration was 16.13±8.5 years. After ranibizumab 0.5 mg loading phase mean BCVA significantly improved from 0.5±1.5 to 0.4±1.4 logMar (p<.0001) and to 0.3±1.5 logMar (p<.0001) after 12 months of follow up. OCT central retinal thickness (CRT) significantly reduced from 583.4±141.5 to 434.4±136.3 μm (p<.0001), and to 427.3±167.7 μm (p<.0001) after 12 months follow-up. Choroidal thickness (CT), measured either manual and automatic (R2 0.9, p<.0001), showed a slight, not significant increase from 189.3±49.9 to 209.6±60.6 after the loading phase and to 191.3± 60.3 μm after 12 months follow-up (p>0.5). Not significant relationship was found between either changes in CRT and BCVA (R2 0.11, p=0.1) and changes in CT and BCVA (R2 0.05, p=0.28). No significant relationship was found between CRT and CT (R2 0.0006, p=0.7).
Conclusions:
Intravitreal injection of ranibizumab in DME eyes causes slight, not significant changes of choroidal thickness associated with an improvement of visual acuity and a reduction of retinal thickness at 12 months of follow up.
Keywords: 499 diabetic retinopathy •
552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
452 choroid