Superficial Parotidectomy: Anterograde Compared with Modified Retrograde Dissection of the Facial Nerve in Benign Parotid Tumors
Abstract
Background: The most common site for salivary gland tumors is the parotid gland; accounting for (64% - 80%) of all cases .The pleomorphic adenoma is the most common tumor (53% to 77%) of all cases in the parotid gland. The treatment of choice for most parotid tumors is surgical excision. One of the main aims of superficial parotidectomy is to minimize injury to the facial nerve and maximize the rate at which it recovers. Two techniques are used for dissection of the facial nerve in parotid surgery: antegrade technique and retrograde technique.
Objectives: The aim of this prospective study is to compare between the two techniques to know the best method of dissection to preserve the facial nerve integrity.
Patients and Methods: This study presents the surgical excision of benign parotid tumors in 60 patients who complained from a mass in the parotid region. These cases were collected from maxillofacial surgery unit in AL-Shaheed Gazi AL-Hariri Hospital / Medical city/Baghdad from May 2009 to July 2011 and in AL-Hussain hospital in Thi-Qar from 2013-2016 .The age of those patients ranged from (19 – 60) years with a mean of 40.9 years. The patients divided into two groups, the 1st group (30 patients) underwent antegrade superficial parotidectomy and the 2nd group (30 patients) were underwent retrograde superficial parotidectomy. The assessment of facial nerve function is categorized into 6 grades according to House- Brackmann grading system. This assessment was started in 1 week, 1 month, 3 months and 6 months postoperatively.
Results: The rate of nerve injury in antegrade technique was 30% at the end of week 1 and 20% at the end of month 1 while for retrograde technique was 40% at the end of week 1 and 10% at the end of month 1, It shows that the nerve injury in week 1 is more in retrograde than antegrade technique .The nerve recovery in antegrade technique was 40% at week 1 and 55% at the end of month 1 while for retrograde technique 70% recovered in the first week and 30% at end of month 1 . It shows that the recovery from injury is faster in retrograde than ante grade technique.
Conclusions: There were more initial serious nerve injuries in the retrograde groups than in the antegrade groups but recovery was faster in the retrograde group. The rate of permanent nerve injury was not affected by the choice of dissection technique.
References
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