The aim of this study was to report the outcome of topical brinzolamide 1% treatment on macular cystoid lesions resembling retinoschisis in 4 patients diagnosed with posterior microphthalmia. The medical records of 4 patients with a clinical diagnosis of posterior microphthalmia who had started topical brinzolamide 1% treatment were reviewed. Visual acuity, central foveal thickness, and cystoid lesion area percentage were used to evaluate treatment response. In the follow-up, there was a decrease in central foveal thicknesses and cystoid lesion area percentages in both eyes of 3 of the patients. However, 1 patient showed increases in both parameters. Visual acuity remained stable in 5 eyes and increased in 3 eyes. Topical brinzolamide treatment may have some positive effects on macular cystoid lesions in selected cases.