Abstract
Purpose: :
To investigate the efficacy 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: :
A total of 32 patients (45 eyes) with DME were randomly assigned to one of three study groups: focal/grid macular laser only (n=15), laser plus IVB (16), or laser plus IVT (14). In the IVB and IVT groups, laser was performed 4 weeks after injection. Outcome measures included best-corrected visual acuity (BCVA), central subfield macular thickness (CSMT) measured by optical coherence tomography, and intraocular pressure (IOP) measured at baseline and at 4, 8, 12 and 16 weeks after treatment.
Results: :
At baseline, mean ± standard error (SE) BCVA (logMAR) was 0.69 ± 0.06 (20/99), 0.77 ± 0.13 (20/117), and 0.70 ± 0.12 (20/100), in the laser, IVB, and IVT groups, respectively (ANOVA: P=0.8558). No significant changes in BCVA from baseline were observed in any of the groups throughout the study period. At baseline, mean ± SE CSMT (µm) was 366.33 ± 24.68, 434.56 ± 32.24, and 418.07 ± 31.58 in the laser, IVB, and IVT groups, respectively (P=0.2453). Within group analysis demonstrated a significant change in CSMT from baseline at 4, 8, 12 and 16 weeks in the IVB group (paired t-test: P<0.05), and at 4, 8 and 12 weeks in the IVT group (paired t-test: P<0.05); there was no significant change in CSMT from baseline in the laser group. Inter-group comparison demonstrated a significant reduction in CSMT in the IVB and IVT groups when compared to the laser group at 4 weeks after treatment (ANOVA: P=0.0352). In the IVT group, IOP was significantly higher than baseline at 4 and 8 weeks after injection (P<0.05). No significant change in IOP was observed throughout the study period in the laser and IVB groups.
Conclusions: :
In contrast to treatment with laser only, laser combined with IVB or IVT was associated with significant CSMT reduction; no significant change in BCVA was observed in any of the study groups.
Clinical Trial: :
www.clinicaltrials.gov NCT00997191
Keywords: edema • diabetic retinopathy • laser