title: First bite syndrome: incidence, risk factors, treatment, and outcomes.
abstract: OBJECTIVE
  First bite syndrome (FBS) refers to facial pain characterized by a severe cramping or spasm in the parotid region with the first bite of each meal that diminishes over the next several bites.1, 2 It is a potential sequela of surgery involving the infratemporal fossa (ITF), parapharyngeal space (PPS), and/or deep lobe of the parotid gland. The incidence, risk factors, treatment options, and outcomes of FBS are poorly understood. We hypothesized that certain clinical and tumor variables independently predict the development of FBS.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  We reviewed the records of 499 patients (mean age, 50 years; range, 12-81 years) undergoing surgery of the deep lobe of the parotid gland, PPS, and/or ITF between 1992 and 2010. Minimum follow-up time was 3 months (median, 39 months). Patient, tumor, and FBS characteristics were analyzed. Incidence was calculated using the Kaplan-Meier method. Univariate analyses and multivariate logistic regression were used to identify independent risk factors for FBS. Patients developing FBS were interviewed to assess the efficacy of various treatment modalities.
  
  
  RESULTS
  FBS developed in 45 patients (incidence, 9.6%), at a mean time of 97 (range, 6-877) days from surgery. On multivariate analysis, three variables were significant independent risk factors for FBS: sympathetic chain sacrifice (odds ratio [OR], 4.7; P = .008), PPS dissection (OR, 8.7; P = .001), and resection of only the deep lobe of the parotid gland (OR, 4.2; P = .002). FBS developed in 48.6% of patients undergoing sympathetic chain sacrifice, 22.4% of patients undergoing PPS dissection, 38.4% of patients undergoing isolated deep lobe parotid resection, and 0.8% of patients undergoing total parotidectomy. Partial resolution of FBS symptoms occurred in 69% and complete resolution in 12%. Of 45 FBS patients, 15 (33%) underwent at least one type of treatment for symptomatic relief. No treatment consistently provided effective symptomatic relief.
  
  
  CONCLUSIONS
  The strongest independent risk factors for FBS are PPS dissection, deep lobe of parotid resection, and sympathetic chain sacrifice. Patients undergoing surgery with dissection and/or manipulation in these anatomical sites and structures should be thoroughly counseled about the risk of developing FBS.
authors.affiliation: Head and Neck Service, Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York, USA.
authors.forename: Gary
authors.initials: G
authors.lastname: Linkov
authors.forename: Luc G T
authors.initials: LG
authors.lastname: Morris
authors.forename: Jatin P
authors.initials: JP
authors.lastname: Shah
authors.forename: Dennis H
authors.initials: DH
authors.lastname: Kraus
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D015331:Cohort Studies; D005157:Facial Pain / Q000453:epidemiology / Q000209:etiology* / Q000628:therapy; D005260:Female; D006801:Humans; D015192:Infratentorial Neoplasms / Q000601:surgery*; D008297:Male; D008409:Mastication; D008875:Middle Aged; D015999:Multivariate Analysis; D009120:Muscle Cramp / Q000453:epidemiology / Q000209:etiology* / Q000628:therapy; D010149:Postoperative Pain / Q000453:epidemiology / Q000209:etiology* / Q000628:therapy; D010307:Parotid Neoplasms / Q000601:surgery*; D035421:Parotid Region; D010610:Pharyngeal Neoplasms / Q000601:surgery*; D012189:Retrospective Studies; D012307:Risk Factors; D013035:Spasm / Q000453:epidemiology / Q000209:etiology* / Q000628:therapy; D013577:Syndrome; D055815:Young Adult