Retrograde Parotidectomy and facial nerve outcomes: A case series of 44 patients.

PURPOSE: The most common surgical method to remove benign parotid tumors remains the prograde approach. We examined if a retrograde surgical technique offers better outcomes than historical prograde controls. MATERIALS AND METHODS: A retrospective chart review at Stanford Hospital was conducted to identify retrograde parotidectomies between February 2012 and October 2014 that were staffed by the senior author (DS) with resident involvement. Facial nerve (FN) outcomes and other post-surgical parameters were recorded. RESULTS: We identified 44 consecutive cases and found that 18.2% (n=8) of patients experienced temporary paresis and 2.3% (n=1) experienced minor (HB 2) permanent paresis limited to one branch. The average hospital length of stay was 0.64 days and complication rate was 6.8%. CONCLUSION: The retrograde technique has complication rates comparable to historical rates for the prograde technique and is amenable to minimally invasive outpatient superficial parotidectomy.

Indications for partial parotidectomy using retrograde dissection of the marginal mandibular branch of the facial nerve for benign tumours of the parotid gland.

The aims of this study were to evaluate the efficacy of partial parotidectomy using retrograde dissection of the marginal mandibular branch of the facial nerve for benign tumours of the parotid gland and to establish the indications for its use. We examined 106 consecutive patients with previously untreated benign tumours in the lower portion of the parotid gland who were treated by parotidectomy. The first group (anterograde group, n=52) consisted of those who had standard anterograde parotidectomy. The remaining patients, who underwent retrograde parotidectomy, were further divided into two groups: those in whom the upper edge of the tumour was located below the mastoid tip (below mastoid group, n=46) or those in whom it was above the mastoid tip (above mastoid group, n=8). The operating time was significantly shorter in the below mastoid group (141.2, 127.5, and 98.1minutes, respectively) as was intraoperative blood loss (41.1, 53.0, and 24.4ml, respectively), compared with the other two groups. There was a higher incidence of facial nerve dysfunction in the above mastoid group postoperatively (4/8) than in the other two groups. The results suggested that the presence of a tumour of any size located below the mastoid tip is a good indication for parotidectomy using retrograde dissection of the marginal mandibular branch of the facial nerve.

A cadaveric study of surgical landmarks for retrograde parotidectomy.

PURPOSE: Retrograde parotidectomy is employed in situations where tumors or scar tissue obscure the facial nerve trunk, making anterograde parotidectomy hazardous. Hence, the reliability of anatomical landmarks in retrograde parotidectomy is of equal practical importance. METHODS: Distances from soft tissue and osseous landmarks to the corresponding peripheral branches of the facial nerve were measured in 41 half-head specimens. The distances were from: i) the zygomatic arch (Z) to the buccal branch (B); ii) the retromandibular vein (RMV) to the marginal mandibular branch (MM); and iii) the angle of the mandible (A) to MM. These distances were compared in left vs, right sides, male vs. female groups, occlusal vs. nonocclusal sides. RESULTS: No statistically significant differences were found in any of the three distances between all groups compared, amongst which, the mean distances from A to MM were the shortest and least variable (Male = 8.9 ± 3.0 mm vs. Female = 6.8 ± 3.5 mm; Left = 7.3 ± 2.8 mm vs. Right = 8.8 ± 3.9 mm; Occlusal = 8.6 ± 3.5 mm vs. Nonocclusal = 7.8 ± 3.4 mm). CONCLUSION: The findings indicate that all three landmarks are useful for surgeons to locate the facial nerve branches during retrograde parotidectomy. Since all three landmarks were consistent indicators for the corresponding facial nerve branches, the surgeon has more than one option should one landmark be obscured by tumors. The optimal landmark is the distance from A to MM because it is shortest and most reliable, followed by RMV to MM, and Z to B.