Advancing Education, Research, and Quality of Care for the Head and Neck oncology patient.
Background: Frey’s syndrome (FS), also known as gustatory sweating, is characterized by sweating and flushing in the preauricular area during food intake. FS is a common complication following parotidectomy, occurring due to damage to the auriculotemporal nerve and aberrant regeneration of parasympathetic fibers that misdirect to the sweat glands of the overlying skin. The incidence of clinically observed FS after parotidectomy is around 40%, while objective rates based on the Iodine-Sublimation Paper Histogram reach about 80%. Various preventative techniques have been explored, including the use of free fat grafts in the parotid bed post-excision to reduce the incidence of this condition. This study evaluates the incidence of FS in patients undergoing parotidectomy with free fat grafting.
Methods: A systematic review was conducted on patients who underwent parotidectomy and received free fat grafts applied to the parotid bed post-excision. The rate was measured using either reports on the incidence of symptomatic FS based on clinical presentation or using Minor’s Starch-Iodine test. Due to low heterogeneity, a single proportions meta-analysis was performed on R-Studio with a fixed effects model.
Results: The study included 5 studies that encompassed 133 patients using free fat grafting. Only 13 patients had incidence of FS. After performing a single proportions analysis using R Studio, the incidence of Frey’s syndrome was 8% following parotidectomy with free fat grafting (95% CI [3%, 12%], P=0.42). Free fat grafting for parotidectomy was associated with a lower incidence of FS compared to without, with an odds ratio (OR) of 0.08 (95% CI: 0.03 to 0.12, p = 0.42, I² = 0%).
Conclusion: Free fat grafting following parotidectomy provides an alternative to conventional grafting methods. However, due to minimal studies describing this complication after parotidectomy and thus a small sample size, statistical significance was not reached. Therefore, further studies are needed to establish the prevalence of Frey’s syndrome in patients undergoing parotidectomy with free fat grafting.