The Effect of Platelet-rich Plasma Nasal Injection in the Treatment of Traumatic Olfactory Dysfunction

Inclusion Criteria: * 18 years of age or older, and loss of olfactory function for more than 6 months after head trauma Exclusion Criteria: * pregnant or lactating women, patients with compromised immune function, patients with acute or chronic sinus infection, patients with nasal polyps, patients with a history of sinonasal cancer, and patients with low platelets or hemophilia and other blood and blood cell-related diseases