Observational Cohort Study on Ocular Chronic Graft-Versus-Host Disease

Inclusion Criteria: * Age ≥14 years, both genders eligible; * First allogeneic hematopoietic stem cell transplantation; * 100 days post-transplantation, with donor hematopoietic stem cell engraftment confirmed; * The subject or their legally authorized representative has provided full informed consent, signed the informed consent form, and is willing to complete subsequent follow-up visits Exclusion Criteria: * Preexisting moderate-to-severe ocular surface disease prior to transplantation; * Active ocular infection; * Presence of other ocular conditions that, in the opinion of the ophthalmologist, may significantly affect the diagnosis of chronic ocular graft-versus-host disease, the evaluation of ocular surface parameters, or the completion of long-term follow-up; * Patients with active hematologic malignancies.