J Korean Ophthalmol Soc.  2020 Jan;61(1):51-58. 10.3341/jkos.2020.61.1.51.

Efficacy of Intravitreal Dexamethasone Implant for Diabetic Macular Edema According to Previous Responses to Bevacizumab

• Kim D
• Park DG
• Ryu G
• Sagong M

• KMID: 2468476
• DOI: http://doi.org/10.3341/jkos.2020.61.1.51

Abstract

PURPOSE
To compare the efficacy of intravitreal dexamethasone implants according to previous response to bevacizumab treatment in patients with diabetic macular edema (DME).
METHODS
Forty-nine eyes of 49 patients who received intravitreal dexamethasone implants for DME were reviewed retrospectively. Of these patients, 13 were treatment-naïve and 36 had previously received intravitreal injections of bevacizumab. Of the 36 previously treated patients, 24 comprised a refractory group showing no response to previous injections, and 12 comprised a responder group showing a response to previous treatments. The best-corrected visual acuity, central macular thickness (CMT), and retreatment percentages were assessed monthly for 6 months.
RESULTS
After the intravitreal dexamethasone implants, visual acuity improved significantly over 6 months in the treatment-naïve group, while in the responder group, a significant improvement in visual acuity was seen at the 2-month follow-up. In the refractory group, there was no significant improvement in visual acuity during the follow-up period. The CMT showed a significant decrease in all three groups, and there was no significant difference in the CMT among the three groups at any time point. Five patients in the treatment-naive group (38.5%), 19 patients in the refractory group (79.2%), and nine patients in the responder group (75.0%) needed retreatment for recurrent macular edema, and there was a significant difference among the three groups in the rate of recurrence (p = 0.034).
CONCLUSIONS
In DME patients, intravitreal dexamethasone implants were associated with a significant anatomical improvement irrespective of previous bevacizumab treatment response. However, the treatment-naïve and responder groups showed improvements in visual acuity, whereas the refractory group showed limited improvement.

Keyword

Bevacizumab; Dexamethasone; Diabetic macular edema; Intravitreal injection; Macular edema

MeSH Terms

Bevacizumab*
Dexamethasone*
Follow-Up Studies
Humans
Intravitreal Injections
Macular Edema*
Recurrence
Retreatment
Retrospective Studies
Visual Acuity
Bevacizumab
Dexamethasone

Figure

• 

  Figure 1 Mean changes in BCVA from baseline during the follow-up period. At each visit of 6-month follow-up, the BCVA improved significantly from baseline in the treatment-naïve group. On the other hand, the responder group showed significant improvement after 2 months of follow-up, and the refractory group did not show improvement during the follow-up period. Among different groups, there were significant differences at 1, 2, and 3 months (p = 0.049 at 1 month, p = 0.023 at 2 months, p = 0.006 at 3 months). BCVA = best corrected visual acuity; logMAR = logarithm of the minimal angle of resolution; Naïve = treatment-naïve group; Refractory = refractory group; Responder = responder group. *Wilcoxon signed rank test vs. baseline; †Kruskal-W allis test for comparisons among the treatment groups.

• 

  Figure 2 Mean changes in CMT from baseline during the follow-up period. The CMT showed significant decrease at each visit in all groups. Treatment-naïve group tended to have a more reduction of CMT than other groups, but there were no significant differences between the groups at each visit. CMT = central macular thickness; Naïve = treatment-naïve group; Refractory = refractory group; Responder = responder group. *Wilcoxon signed rank test vs. baseline; †Kruskal-Wallis test for comparisons among the treatment groups.

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