Hyperreflective Dots on SD-OCT: Implications for Predicting Treatment Outcomes in Diabetic Macular Edema

Objectives: To evaluate the relationship between hyperreflective dots (HRDs) observed on spectral-domain optical coherence tomography (SD-OCT) and the outcomes following treatment with intravitreal ranibizumab or dexamethasone injections in patients with diabetic macular edema (DME). Methods: This retrospective study focused on individuals suffering from diabetic macular edema (DME) who underwent a sequence of three intravitreal ranibizumab injections. Based on treatment response, the eyes were categorized into two groups: responders and non-responders. The non-responder group subsequently received intravitreal dexamethasone (IVO) implants. Treatment results were evaluated by changes in BCVA, HRD number, and central macular thickness (CMT). Results: This research involved 112 eyes from 78 participants who had been diagnosed with DME. Seventy-three eyes (65%) were identified as ranibizumab responders and 39 eyes (35%) as ranibizumab non-responders. Of the 39 individuals who had suboptimal response to ranibizumab and subsequently received treatment with an intravitreal dexamethasone implant, 26 eyes (66.67%) exhibited a favorable response, while 13 eyes (33.33%) showed an insufficient response. IVR responders demonstrated significantly greater improvements in BCVA (0.54 ± 0.73 to 0.35 ± 0.40 logMAR vs. 0.52 ± 0.61 to 0.47 ± 0.38 logMAR) and CMT (456.53 ± 109.73 μm to 235.47 ± 49.13 μm vs. 468.99 ± 127.10 μm to 427.45 ± 52.91 μm) reduction. Baseline analysis revealed IVR non-responders had higher counts of both inner and outer retinal HRDs compared to responders (9.09 ± 3.38 vs. 7.07 ± 2.32 and 5.46 ± 2.03 vs. 4.27 ± 1.87, p < 0.05, respectively). Eyes with initially higher numbers of inner retinal HRDs, outer retinal HRDs, and subretinal HRDs demonstrated a significantly enhanced response to dexamethasone therapy (9.03 ± 3.18 vs. 7.55 ± 2.72, 6.55 ± 2.46 vs. 4.79 ± 1.88 and 0.27 ± 0.54 vs. 0.21 ± 0.47, p < 0.05, respectively). Conclusions: HRDs could potentially be used as a predictive biomarker to assess the effectiveness of anti-VEGF therapy in treating DME. Patients exhibiting a greater number of retinal HRDs tend to have less favorable reactions to anti-VEGF treatments but experience improved results with dexamethasone.