Transcervical resection of the styloid process in Eagle syndrome.

Abstract

We conducted a retrospective study to determine the treatment outcomes of 6 patients who had either unilateral or bilateral elongated styloid processes and symptoms consistent with Eagle syndrome. Five of these patients had undergone transcervical resection of the styloid process, with relief of symptoms over the follow-up period (mean: 8 mo). Two of the 5 patients experienced a transient weakness in the marginal mandibular nerve, and both recovered completely. The transcervical surgical approach to resection in patients with elongated styloid processes and Eagle syndrome appears to be safe and effective, although the risk for transient marginal mandibular nerve weakness is notable.

Introduction

Eagle syndrome represents a constellation of symptoms, most notably facial pain, that are believed to be related to an elongated styloid process. The syndrome was described as early as 1870, but it attained its eponymic designation after Eagle categorized the syndrome into two distinct types--the classic type and the carotid artery type--in 1937. (1) The classic type is seen after tonsillectomy, when the patient experiences pain that is attributable to the stimulation of cranial nerves V, VII, IX, and X. In the carotid artery type, symptoms occur when the elongated styloid process stimulates the sympathetic nerves in the carotid sheath. (1,2)

The styloid process is a bony outgrowth of the temporal bone that extends, by means of the styloid ligament, toward the lesser cornu of the hyoid bone. The reported incidence of an elongated styloid process, defined as one that is longer than 25 mm, ranges from 1 to 7% of the population, yet only 4 to 7% of these patients experience related symptoms. (2,3) In addition to facial pain, symptoms of Eagle syndrome include ear pain, difficulty swallowing, voice changes, and a foreign-body sensation in the throat that prompts frequent swallowing. Affected patients often undergo extensive medical testing aimed at identifying the cause of pain and difficulty swallowing.

Although the physical and psychological impact of Eagle syndrome has been documented, no report in the American otolaryngology literature has focused on the outcomes and complications related to the transcervical approach to surgical therapy. In this brief report, we describe our retrospective review of the outcomes of such surgery in a small number of patients with this uncommon disorder.

Patients and methods

Patient characteristics. Between July 2002 and July 2004, 6 patients--all women, aged 37 to 54 years (mean: 45)--presented to the Department of Otolaryngology and Communication Sciences at the Medical College of Wisconsin in Milwaukee with an elongated styloid process and symptoms consistent with Eagle syndrome (table). Approval for our study protocol was granted by our institutional review board.

Among the 6 patients, 3 had presented with right-side elongation, 1 with left-side elongation, and 2 with bilateral elongation (table). There were a total of 4 complaints of oropharyngeal pain, 2 of otalgia, 2 of dysphagia, 1 of a foreign-body sensation, and I of syncopal episodes when turning the head (~25 times during a 1-year period).

Five of the 6 patients had undergone transcervical resection of the styloid process; the remaining patient had been offered surgical treatment and declined.

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The transcervical approach. With the patient under general anesthesia, an incision is made at or below the lower aspect of the submandibular gland. The inferior aspect of the gland is identified, and the gland is bluntly dissected from its attachments to the digastric muscle and the floor of the submandibular fossa. The fascia overlying the gland, in which the marginal mandibular nerve runs, is not disturbed by the dissection. The contents of the submandibular triangle are retracted superiorly and anteriorly, and the elongated styloid is palpated in the floor of the fossa. The facial artery may be ligated at this point, but it is not necessary. The lingual nerve is identified and preserved. The tip of the styloid is bluntly cleaned of fascial attachments until the bone is exposed (figure 1). Once this plane is achieved, a Kitner or Freer elevator is used to clear all attachments of the styloid as superiorly as possible up to the skull base. A rongeur is used to fracture the styloid as proximally as feasible. The energy of the fracture is directed away from the facial nerve at the skull base. The wound is irrigated and closed over a small drain overnight.

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Results

In the 5 patients who underwent surgery, the length of the resected portion of the styloid process ranged from 0.9 to 3.5 cm (mean: 2.4) (figure 2). All 5 patients experienced a complete relief of symptoms during the immediate postoperative period, and the relief was sustained in all patients over a follow-up that ranged from 4 to 16 months (mean: 8) (table). Two of the 5 patients experienced transient weakness of the marginal mandibular nerve; one of these cases resolved 3 months postoperatively and the other after 4 months. No other complications of surgery occurred.

Discussion

In reviewing the findings of this modest investigation, the challenges related to the care of these patients became evident. Most of them had seen an array of physicians and were given numerous diagnoses, from temporomandibular joint disorder to migraine headache.

According to the literature, Eagle syndrome can be diagnosed clinically by physical examination. The diagnosis can be established by transoral palpation of the styloid in many cases. Palpation of the intraoral end of the styloid may elicit pain or discomfort similar to that described during the patient's history. Lee and Hillel have described the radiographic diagnosis of Eagle syndrome with three-dimensional computed tomography (CT), but subsequent advancements in imaging technology have improved the diagnostic yield only marginally. (4) CT images allow physicians to appreciate both the bony anatomy and the relationship of the styloid process to critical neurovascular structures. (4)

Numerous therapeutic approaches, both conservative and invasive, have been used to treat Eagle syndrome in the setting of an elongated styloid process. Nonsurgical therapies have not consistently provided long-term relief, (5) so surgery continues to be the mainstay of treatment. The earliest reported intervention involved manual transoral fracture, but the effect of this procedure on symptoms proved to be unpredictable. (6) The main controversy today involves the surgical approach.

The transoral approach, introduced by Eagle himself, offers the advantages of a direct approach and no external scarring. (2) Its limitations include poor visibility leading to an increased risk of neurovascular injury, oral flora contamination, and the potential for postoperative airway obstruction secondary to pharyngeal edema. (3) The transcervical approach offers better exposure and better visualization of the neurovascular structures in the surgical site, better field sterility, and the ability to excise a larger portion of the styloid process. (3,5) On the other hand, this approach does require an external incision, and the recovery period maybe longer. The transcervical approach also places the marginal mandibular branch of the facial nerve at risk of transection, which may result in postoperative lip weakness, but this risk can be minimized by careful dissection in the appropriate plane. The 2 cases of postoperative weakness in our series likely occurred as a result of compression of the nerve, as access to the skull base requires significant steady retraction of the overlying soft tissues. Fortunately, both of these patients recovered completely.

Conclusion

The transcervical surgical approach to resection in patients with elongated styloid processes and Eagle syndrome is safe and effective. The possibility of marginal mandibular nerve weakness should be discussed with the patient.

References

(1.) Eagle WW. Elongated styloid process: Report of two cases. Arch Otolaryngol 1937;25:584-7.

(2.) Eagle WW. Elongated styloid process; symptoms and treatment. AMA Arch Otolaryngol 1958;67(2):172-6.

(3.) Boscainos PJ, Papagelopoulos PJ, Goudelis G, et al. Eagle's syndrome. Orthopedics 2004;27(4):423-5.

(4.) Lee S, Hillel A. Three-dimensional computed tomography imaging of Eagle's syndrome. Am J Otolaryngol 2004;25(2):109.

(5.) Diamond LH, Cottrell DA, Hunter MJ, Papageorge M. Eagle's syndrome: A report of 4 patients treated using a modified extraoral approach. J Oral Maxillofac Surg 2001;59(12):1420-6.

(6.) Glogoff MR, Baum SM, Cheifertz I. Diagnosis and treatment of Eagle's syndrome. J Oral Surg 1981;39(12):941-4.

Timothy J. Martin, MD; David R. Friedland, MD, PhD; Albert L. Merati, MD

From the Department of Otolaryngology and Communication Sciences, the Medical College of Wisconsin, Milwaukee.

Corresponding author: Albert L. Merati, MD, Department of Otolaryngology-Head and Neck Surgery, University of Washington, Box 356515, Health Sciences Bldg., Suite BB 1165, Seattle, WA 98195-6515. Phone: [phone]; fax: [phone]; e-mail: amerati@ uwashington.edu

The information in this article was originally presented as a poster at the Middle Section meeting of the Triological Society; Jan. 21-23, 2005; Chicago.

Table. Data collected for comparison

           Age (yr)
                          Weight
Pt.    Onset   Dx   Sx    (lbs)

1       40     41   41     146
2       51     51   52     140
3       50     55   55     168
4       40     54   54     168
5       37     38   38     143
6       54     55   N/A    139

Mean    45     49   48     151

       Presenting   Medical    Diagnostic    Side of
Pt.     symptoms    history      tests      elongation

1          P           H           CT         Right
2       FB, O, D    PT, D, A    CT, MBS       Right
3          O           D        CT, EEG,    Bilateral
                                  CNB
4         P, D         S        CT, MRI       Right
5         S, P         D        CT, MRI,       Left
                                TEE, AG
6          P           D           CT       Bilateral

Mean

       Length of styloid   MM nerve   F/U
Pt.      resection (cm     weakness   (mo)

1             1.1            Yes       4
2             3.5             No       16
3             0.9             No       6
              3.5            Yes       6
4             3.0             No       8
5             N/A            N/A      (17)
              2.4                      8
6

Mean

Key: Age: Dx = diagnosis, Sx =surgery. Presenting symptoms:
P = oropharyngeal pain, FB = foreign-body sensation, O = otalgia,
D = dysphagia, S = syncopal episodes. Medical history:
H = hypothyroidism, PT = prior trauma to the neck, D = depression,
A = anxiety disorder, S = sarcoidosis. Diagnostic tests:
CT = computed tomography of the neck, MBS = modified barium swallow,
EEG = electroencephalography, CNB = cervical nerve block,
MRI = magnetic resonance imaging, TEE = transesophageal
echocardiography, AG = arteriography. Postoperative transient nerve
weakness: MM = marginal mandibular.