Visual and anatomic responses to a previous dexamethasone (DEX) implant predicts patient response after switching to fluocinolone acetonide (FAc) implant, a recent study has found.
Researchers conducted a retrospective cohort analysis of 44 eyes from 33 patients with diabetic macular oedema who had undergone at least one DEX injection in the past. Changes in best-corrected visual acuity (BCVA) and central macular thickness (CMT) were used as measures of DEX response, while steroid response was defined as intraocular pressure (IOP) >21 mm Hg or an increase of ≥5 mm Hg. The same metrics were used to assess FAc response.
A total of nine eyes (nine patients) and 29 eyes (22 patients) showed good functional and morphological response to DEX, respectively. Twelve months after switching to FAc, both BCVA (p=0.04) and CMT (p<0.001) showed significant improvements.
Notably, CMT significantly decreased in participants who showed good morphological response to DEX, an effect that was apparent as early as 2 months after switching and persisted until the final follow-up (p<0.001). No such effect was reported for patients who were poor responders to DEX.
BCVA showed a similar pattern, with better improvements in good responders to DEX, though the between-group difference did not reach statistical significance (p=0.9).
In terms of safety, the researchers detected nine eyes with elevated IOP after FAc, with a mean increase of 3.7 mm Hg after 12 months. Patients who experienced IOP-related events after DEX implantation also had a significantly higher IOP after FAc (p=0.03).