Non-diabetic patients who underwent vitrectomy for macular hole or pucker represented the control group (CTRLs); their inclusion criteria were: age greater than 18 years and the presence of macular pucker or macular hole requiring vitrectomy. Exclusion criteria were: age less than 18 years, diagnosis of diabetes mellitus, and previous vitrectomy in the eye under examination or other ophthalmic surgery or laser therapy within the previous 3 months. All patients underwent a complete ophthalmologic examination (visual acuity, slit lamp, tonometry, fluorescein retinal angiography, and optical coherence tomography -OCT-). Informed consent was obtained from all patients after a detailed description of the aims and procedures of the study.