AB194. SOH24AB_187. Perioperative outcomes in parotid surgery

Background: Parotid surgery poses significant risk of postoperative morbidity, primarily facial nerve dysfunction. Adjunctive tools such as fine needle aspiration (FNA) and facial nerve stimulation (FNS) are controversial and subject to operator variability. The objective of this review was to examine a myriad of perioperative measures that may influence post-operative surgical outcomes.

Methods: A two-year retrospective case series of patients who underwent parotid surgery, within the Oral & Maxillofacial Surgery Department of University Hospital Limerick, was undertaken. Variability in perioperative measures—namely imaging modality, FNA and FNS—were recorded. Facial nerve dysfunction, as denoted by the House-Brackmann (HB) scale, was the primary outcome measured.

Results: A total of 22 patients underwent superficial or total parotidectomy. The majority of patients were male (77%), with a median age of 59 years [interquartile range (IQR): 50.5–72 years]. Radiographic reports were often inaccurate with regards to tumour extension (19%) or did not specify tumour site within the parotid lobes (46%). Although FNA result always correlated with histopathological diagnosis, 36% of FNAs were inconclusive. The positive predictive value of FNS, for satisfactory facial nerve function at one-month post-op (HB ≤2), was 80%. The majority of intra-parotid pathology was benign, most commonly Warthin’s tumour (45%). Patients that exhibited a HB of ≥ IV at one-month post-op had significantly greater median tumour size than those with a HB of < IV (50 versus 32.5 mm).

Conclusions: Current radiographic reporting offers limited information with regards to extension of intra-parotid tumours. FNS and tumour size may serve as a quasi-indicator of facial nerve function following parotid surgery.

Keywords: Facial nerve stimulation (FNS); fine needle aspiration (FNA); House-Brackmann scale (HB scale); parotidectomy; parotid tumour