Abstract
Purpose: :
To compare the effects of macular laser photocoagulation combined with intravitreal injection of 1.5 mg bevacizumab (IVB) or 4 mg triamcinolone acetonide (IVT) for diabetic macular edema (DME).
Methods: :
49 patients (64 eyes) with DME were randomly assigned to one of three study groups: focal/grid macular laser (Laser; n=23), laser plus IVB (IVB; n=21), or laser plus IVT (IVT; n=20). Laser was performed 4 weeks after injection. Retreatment was performed at weeks 20 and 40 if central subfield macular thickness (CSMT) higher than 275 µm. Outcome measures included best-corrected visual acuity (BCVA), CSMT measured by optical coherence tomography, and intraocular pressure (IOP) measured at baseline and at 4, 8, 12, 16, 24, 36, and 52 weeks after treatment.
Results: :
31 patients completed the 52-week study period (Laser: n=17 eyes; IVB: n=13; IVT n=12;). At baseline, mean ± SE BCVA (logMAR) was 0.65 ± 0.08; 0.63 ± 0.07; 0.68 ± 0.06 in the Laser, IVB, and IVT groups respectively (P=0.8888). Statistically significant improvement in BCVA from baseline was observed within IVT group at weeks 16, 24 and 36. Mean ± SE BCVA (LogMAR) intra-individual difference to baseline was respectively: 0.19 ± 0.07 (P=0.0212), 0.23 ± 0.10 (P=0.0300), 0.25 ± 0.09 (P=0.0147). However, intergroup analyses revealed no differences between BCVA changes in any of the groups throughout the study period. At baseline, mean ± SE CSMT (µm) was 421.4 ± 122.6; 410.2 ± 88.0; 402.3 ± 85.2 in the laser, IVB, and IVT groups, respectively (P=0.8722). Significant reduction in CSMT was observed at all study periods in all 3 groups (P<0.05). No significant difference between groups’ CSMT change was observed in any study period (P>0.05). In the IVT group, IOP was significantly higher at 8 weeks after injection (P<0.05).
Conclusions: :
One-year results showed no difference between CSMT improvements found after Laser with or without IVT or IVB association. The association of LASER and IVT was the only one associated with significant improvement in BCVA.
Clinical Trial: :
http://www.clinicaltrials.gov NCT 00997191
Keywords: diabetic retinopathy • laser • injection