This is a prospective, single-center, single-arm, non-comparative descriptive pilot study evaluating autologous platelet-rich plasma (PRP) injections in adults with persistent (\>6 months) non-tumoural olfactory dysfunction, either age-related degenerative olfactory dysfunction (DOD) or post-traumatic olfactory dysfunction (DOPT). Participants receive three PRP injections over 4 weeks (Day 0, Day 14, Day 28), with follow-up visits at Month 3 and Month 6 after the first injection. Olfactory function is assessed using the Sniffin' Sticks Test (TDI score). Patient-reported outcomes include SNOT-22 and a visual analog scale (VAS) for perceived olfactory impairment. Safety is assessed through adverse event collection.
Adults with persistent (>6 months) non-tumoural olfactory dysfunction: age-related degenerative olfactory dysfunction (DOD) or post-traumatic olfactory dysfunction (DOPT).
Objective olfactory impairment confirmed by Sniffin' Sticks Test (TDI ≤ 30.5/48).
MRI within the last 6 months after onset excluding tumoural etiology or central cause.
Normal nasal endoscopy.
Inflammatory rhinosinus disease (e.g., nasal polyposis) or granulomatosis with polyangiitis.
Coagulation disorder.
Brain radiotherapy history or ongoing chemotherapy.
Olfactory disorder temporally linked to SARS-CoV-2 infection (delay <1 month).