The goal of this observational study is to evaluate the expression characteristics and clinical relevance of the tRF-31/HIPK2 signaling axis in adults over 18 years old with age-related cataract (ARC). The main questions it aims to answer are: Is there a correlation between the relative expression levels of tRF-31 and its target gene HIPK2 in the anterior lens capsule and the clinical severity (Emery-Little grading system) of age-related cataracts? Does oxidative stress in the anterior segment microenvironment have a potential bystander effect on the state of the corneal endothelium? Participants will:Undergo routine preoperative ophthalmologic examinations, including visual acuity tests, slit-lamp photography, and corneal endothelial cell counting. Undergo standard cataract surgery (phacoemulsification combined with intraocular lens implantation) as part of their regular medical care. Allow researchers to collect and analyze their anterior lens capsule tissue, which is routinely removed and typically discarded as medical waste during the standard continuous curvilinear capsulorhexis (CCC) step of the surgery.

Inclusion Criteria:

Patients older than 18 years. Clinically diagnosed with age-related cataract (ARC) and have clear surgical indications for routine phacoemulsification combined with intraocular lens (IOL) implantation. Scheduled to undergo cataract extraction and intraocular lens implantation. Completed routine preoperative corneal endothelial specular microscopy, providing objective data including cell density, coefficient of variation of cell area, and the proportion of hexagonal cells. Provided signed written informed consent.

Exclusion Criteria:

History of ocular trauma, glaucoma, episodes of active uveitis, or previous intraocular surgery. Presence of severe systemic diseases rendering the patient unsuitable for surgery. Poor patient compliance or coexisting psychiatric disorders. Severe systemic metabolic syndromes (e.g., diabetes). Diagnosis of high myopia. Current participation in other clinical trials or likelihood of being lost to follow-up.

The study population consists of adult patients over 18 years of age who have been clinically diagnosed with age-related cataract (ARC) and are scheduled to undergo routine phacoemulsification combined with intraocular lens implantation at the Eye Center of the Second Affiliated Hospital, Zhejiang University School of Medicine.