A Prospective, Multicenter, Post-marketing Clinical Follow-up Research to Evaluate the Long-term Safety of Ellansé-S Dermal Filler Made of PCL Microspheres for the Correction of Moderate-to-severe Nasolabial Folds

Inclusion Criteria: 1. 18 years old and above; 2. Subjects with moderate-to-severe nasolabial folds (3-4 level of WSRS scores) on both sides of the face 3. Intended to be treated with PCL microsphere filler; 4. Voluntarily participate in this test, cooperate with follow-up, and sign an informed consent form Exclusion Criteria: 1. Obvious acne scar, pigmentation, active infection, inflammation, tumor, precancerous lesion or unhealed wound in the intended injection area; 2. Patients who have used permanent fillers (PMMA, hydrogel polymer, liquid silicone for injection, polyvinyl alcohol (PVA), bone cement, autologous fat, etc.) for nasolabial groove injection; 3. Patients who have received semi-permanent fillers (polycaprolactone, L-polylactic acid, hydroxyapatite, platelet-rich plasma, etc.) injection treatment in nasolabial sulch area in the past 24 months; 4. Patients who have received temporary fillers (hyaluronic acid, collagen, etc.) injection treatment in nasolabial groove in the past 12 months; 5. Patients who have received botox injection treatment in nasolabial sulci in the past 6 months; 6. The nasolabial groove has been treated with beauty plastic, focused ultrasound, chemical stripping, photoelectric (laser, photon, radio frequency) in the past 3 months; 7. Use of hormones or immunosuppressants within the past 1 month; 8. Subjects who have used anticoagulants in the last 2 weeks; 9. Subjects with a history of crabfoot, hyperplastic scars or cicatricial constitution; 10. Subjects with active sepsis; 11. Subjects with coagulation dysfunction; 12. Subjects with autoimmune diseases; 13. Allergic to polycaprolactone or known product ingredients; 14. Pregnant, pregnant and lactating subjects; 15. Participated in other clinical trials in the past 30 days; 16. Other situations determined by the researcher to be unsuitable for participation in this study;