Intravitreal pegaptanib sodium (Macugen®) for treatment of diabetic macular oedema: a morphologic and functional study

Authors


Professor Ciro Costagliola MD, Dipartimento di Medicina e Scienze per la Salute, Università degli Studi del Molise, Via F. De Sanctis, snc, 86100 Campobasso, Italy. Tel.: +39 0874 404858, Fax: +39 0874 418485, E-mail: ciro.costagliola@unimol.it

Abstract

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• Diabetic macular oedema can develop at all stages of diabetic retinopathy (DR), and its prevalence increases with the duration of diabetes, affecting approximately 30% of diabetic patients after 25–30 years of disease.

• Elevated concentrations of VEGF have been identified in aqueous humour and vitreous of patients with DR, and the severity of macular oedema is correlated with its vitreous concentrations.

• Intravitreal anti-VEGFs exert a key role in the treatment of diabetic macular oedema.

WHAT THIS STUDY ADDS

• The present study, performed on 30 eyes of 30 patients, shows that intravitreal pegaptanib injections induced a significant reduction in mean central retinal thickness, with a parallel improvement in visual acuity.

• For the first time a correlation between retinal morphologic and functional parameters in diabetic patients with macular oedema has been ascertained.

• Our study demonstrates that the selective inhibition of VEGF-165 isoform by pegaptanib represents an effective treatment for diabetic macular oedema, as assessed throughout a 48 week follow-up.

AIMS To study whether morphologic (foveal thickness, FT) variations of clinically significant macular oedema (CMO) in patients suffering from diabetes following intravitreal pegaptanib sodium (IVP) injection were associated with functional [macular sensitivity (MS) and colour discrimination (CD)] changes.

METHODS A longitudinal, interventional, non-randomized study was performed. FT was assessed by optical coherence tomography (OCT), MS by microperimetry, best-corrected visual acuity (BCVA) by early treatment diabetic retinopathy study charts (ETDRS) and CD by Farnswoth-Munsell test. The treatment protocol consisted of three consecutive injections (0.3 mg/0.05 ml; baseline, week 6 and week 12). Follow-up checks were scheduled at 18, 24, 36 and 48 weeks, after injections.

RESULTS Thirty eyes of 30 patients with clinically significant CMO were included for analysis. After IVP a significant decrease of FT occurred with a mean reduction from baseline of 56.9% (P= 0.0001). An improvement of functional parameters was recorded in all patients (BCVA from 18.2 ± 8.5 letters to 25.5 ± 8.4 letters, P < 0.005, MS from 8.6 ± 2.16 dB to 10.6 ± 2.61 dB, P < 0.001, colour analysis from 376.1 ± 125.6 TES to 116 ± 34.6 TES, P= 0.0001). A statistically significant correlation between FT and BCVA as well as MS and CD was also found. Neither ocular nor systemic adverse events were reported.

CONCLUSIONS Intravitreal pegaptanib significantly reduced FT, with a concomitant improvement of MS and CD. This association emphasizes the efficacy of IVP in the treatment of CMO.

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