Effects of Pars Plana Vitrectomy on the Ocular Surface in Patients with Dry Eye Disease

INTERVENTION: control group:0.1% sodium hyaluronate eye drops.;study group:0.05% cyclosporine eye drops; CONDITION: Dry eye disease (DED) PRIMARY OUTCOME: schirlmer test;OSDI score; SECONDARY OUTCOME: Tear BUT;Corneal fluorescein staining (CFS) score;Tear Meniscus Height (TMH); INCLUSION CRITERIA: 1.Aged 18 years or older, of either gender; 2.Preoperatively diagnosed with dry eye disease, defined as the presence of dry eye‐related symptoms, an Ocular Surface Disease Inde X(OSDI) score >13, and a non‐invasive tear break‐up time (NIBUT) <10 seconds; 3.Scheduled to undergo 25‐gauge pars plana vitrectomy (PPV) for fundus diseases (e.g., diabetic retinopathy, retinal detachment, macular hole, epiretinal membrane); 4.Willing to participate and able to provide written informed consent.