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Eagle's syndrome: A review
Review Article Eagle’s Syndrome:
A Review
Jay S. Rechtweg, MD, and Mark K. Wax, MD, FACS, FRCS (C)
Demanchetis described a calcified stylohyoid ligament in 1852. * Weinlecher described symptoms related to an elongated styloid process in 1872. He treated the symptoms by removal of the pr0cess.l In the 193Os, Watt W. Eagle of Duke University began to define a syndrome resulting from an elongation of the styloid process .lm4 This syndrome occurred after tonsillectomy and presented as a dull, long-term pain in the throat; occasional globus; dysphagia and headache; and pain that radiated to the ear. In the ensuing years, the term Eagle’s syndrome has become a diagnosis that encompasses a series of conditions resulting from pathologic conditions related to the styloid process. Anatomy
and Embryology
The styloid process is a slender bony projection arising from the lower surface of the petrous portion of the temporal bone. In the fetus this process originates from Reichert’s cartilage of the second brachial arch. This region of Reichert’s cartilage has four separate centers of development: the tympanohyal, the stylohyal, the ceratohyal, and the hypohyal.5s6 The tympanohyal originates at the temporal bone and becomes the base of the styloid process. This region will continue to undergo calcification over the first 8 years of life. The stylohyal becomes the shaft of the styloid process. The degree of calcification of this From the Department of Otolaryngology, Head and Neck Surgery, State University of New York at Buffalo, Buffalo, NY. Address reprint requests to Mark K. Wax, MD, FACS, FRCS (C), Department of Otolaryngology, Head and Neck Surgery, State University of New York at Buffalo, 135 LeBrun Rd, Buffalo, NY 14215. Copyright o 1998 by W.B. Saunders Company 0196-0709/98/l 905-0012$8.00/O 316
American
Journal
of Otolatyngology,
division determines the overall length of the styloid process. The ceratohyal portion becomes the stylohyoid ligament. In many animals this portion may ossify and become a bone referred to as the epihyal.‘jr7 The hypohyal develops into the lesser cornu of the hyoid bone. There have been rare instances where Reichert’s cartilage has failed to undergo the programmed development and has instead developed into a bar of bone extending from the temporal bone to the hyoid bone.5 The styloid process projects inferiorly and anteriorly into the parapharyngeal space.4 In the parapharyngeal space the styloid process is in close proximity to a multitude of structures. The retrostyloid compartment contains the internal jugular vein; the internal carotid artery; the sympathetic chain; and the glossopharyngeal, vagus, accessory, and hypoglossal nerves. The prestyloid compartment contains the internal maxillary artery, the lingual and auricotemporal nerves, and is related to the tonsillar fossa inferiorly. The involvement of some or all of these structures in the parapharyngeal space has been attributed to the origin of the pathologic conditions related to Eagle’s syndrome. Three muscles, the stylopharyngeus, the stylohyoid, and the styloglossus, each with a different innervation, are attached to the styloid process. The stylopharyngeus muscle has its origin at the inner side of the base of the styloid process and inserts into the posterior border of the thyroid cartilage in conjunction with the palatopharyngeus. This muscle pulls the pharynx up and outward during deglutination and is innervated by the glossopharyngeal nerve. The stylohyoid muscle originates at the posterior and lateral portions of the styloid and travels inferiorly and anteriorly to the body of the hyoid bone, adjacent to the greater
Vol 19, No 5 (September-October),
1998:
pp 316-321
EAGLE’S
SYNDROME
cornu. The stylohyoid muscle, in conjunction with the digastric, mylohyoid, and geniohyoid muscles, acts to raise the hyoid bone with the base of the tongue during deglutination. This muscle is innervated by the facial nerve. The styloglossus muscle has its origin on the anterior lateral portion of the styloid process, near its apex. This muscle travels inferiorly and anteriorly to insert into the lateral portion of the tongue. This muscle is one of the extrinsic muscles of the tongue, and as such, is innervated by the hypoglossal nerve. Two ligaments take origin on the styloid process. The stylohyoid ligament, derived from the ceratohyal portion of Reichert’s cartilage, extends from the apex of the styloid ligament to the tip of the lesser cornu of the hyoid bone. The stylomandibular ligament travels from the apex of the styloid process to the posterior border of the mandibular ramus, between the masseter and the ptyergoid muscles. This ligament runs with the styloglossus muscle and acts as an accessory to mandibular articulation. Eagle believed that a normal-length styloid process was about l-in. (2.5 cm) long.3 Moffat, Ramsden, and Shaw have measured the styloid process in 2,000 skulls and 80 postmortem examinations and have determined that the average length of the styloid process varies from 1.52 to 4.77 cm (mean 3.15 cm).8 Stafne and Hollinshead believed the normal length of a styloid process to be 2.0 to 3.0 crne8 The origin of the elongated styloid process is poorly understood. Embryologically, it may be caused by increased calcification of the stylohyal, which resulted in the long body of the styloid process. Furthermore, the ceratohyal and/or the stylohyoid ligament may become ossified. The cause of the ossification may be because of the embryologic potential to differentiate into the epihyal bone or in response to trauma.
317
to have related symptoms. Eagle4 believed that 4% were symptomatic. Kaufman et al found that 10.3% of 68 patients with elongated styloids were symptomatic.5a6 Correll et al found that 7.8% of 103 patients were symptomatic516 Keur et al6 found 53% of women and 40% of men had a symptom that may be related to the styloid (measuring facial pain, tinnitus, odynophagia, and pain when turning the head). The incidence of an elongated styloid process is reported to be between 4% and 28%, with most investigators defining an elongated styloid as being greater than 3 cm in length.‘j Keur et al6 examined 1,135 panoramic radiographs of the mandible in edentulous patients. This group reported that 32.9% of the female and 28.5% of the male patients had elongated styloid processes. They found the average length of the styloid to be 4.79 cm for men (standard deviation of 1.285 cm on the right and 1.328 cm on the left) and 4.45 cm in women on both the right and left sides. CASE REPORTS Patient 1 Patient 1 is a 48-year-old white man who presented to the Otolaryngology Clinic with a chronically enlarged styloid process. Five years before his presentation, he developed right throat pain and odynophagia. Investigation showed an elongated styloid process (Fig 1). This was easily palpated transorally, and he was diagnosed with Eagle’s syndrome. An oral surgeon treated him by fractur-
Incidence Approximately 4% of the population are believed to have an elongated styloid process. With the increased use of the panoramic radiograph for routine dental films, the incidental finding of an elongated styloid is increasing. Only a small percentage of the population with an elongated styloid process is believed
Fig 1. Plain radiograph of the left side of the neck patient 1 showing an elongated styloid process.
of
318
RECHTWEG
ing the styloid process through an intraoral approach. This resolved his pain for 6 months. The resumption of the pain prompted him to seek a second opinion. He was referred to the Otolaryngology Service. After appropriate evaluation, surgical correction of his problem was suggested. The patient underwent an uneventful extraoral resection of a 4.5cm styloid process (Fig 2). He had an overnight hospital admission. With more than 3 years of follow-up, he has had no recurrence of symptoms or any intraoral complaints to date.
Patient 2 A 3 y-year-old white man presented to the Otolaryngology Clinic with a history of progressive dysphagia over the past several years. Approximately 10 years before, he underwent a tonsillectomy. He began to have problems swallowing 5 years before presentation. He was evaluated by a number of specialists with no clear diagnosis until a Panarex radiologic study was performed. The film showed an elongated styloid process. Subsequent physical examination showed the process to be palpable in the tonsillar fossa. During further questioning of the patient, a history of fracturing the styloid was obtained. Conservative therapy relieved his symptoms for a short period of time. When his symptoms returned, surgery was suggested and agreed to by the patient. An external approach to the styloid was undertaken (Figs 3 and 4). A s-cm length of styloid process was removed. He recovered uneventfully. At present, he has had greater than 4 years of follow-up with no noted recurrence of his symptoms.
DISCUSSION Symptoms Classic Eagle’s syndrome occurs in the middle-aged patient at any time after a tonsillectomy. Eagle described: A nagging somewhat
or aching sensation in the throat similar to chronic pharyngitis. ...
2
Fig 2.
The
resected
4
3
styloid
5
process
7
6
of patient
1.
AND
WAX
Pain may radiate to the middle ear or mastoid region. Frequently a sensation of a foreign body having lodged in the pharynx is noticed. There may be difficultyin swallowing.’
Other symptoms associated with this form of Eagle’s syndrome include headache and pain when turning the neck, pain when extending the tongue, change in voice, and a sensation of hypersalivation. w Patients often believe that they have not properly healed from their tonsillectomy. All these symptoms may be considered a form of pharyngeal or neurological irritation. The scarring after a tonsillectomy may lead to contracture of the tonsillar fossa, thus pulling it taut over an elongated styloid process.*-4s8 The pain may be transmitted through the trigeminal nerve, the facial nerve, the glossopharyngeal nerve, or the vagus nerve, all of which provide sensory innervation the pharyngeal mucosa. Furthermore, many of the symptoms may be attributed to the anatomical relation to the styloid process. Pain in the neck when turning the head may be attributed to irritation of any of the nerves in the retrostyloid compartment. Pain when extending the tongue and the odynophagia may be attributed to movement of the musculature and ligaments attached to the styloid process (ie, the styloglossus muscle in relation to tongue protrusion and the stylopharyngeus and stylohyoid muscles and the stylohyoid and stylomandibular ligaments in relation to deglutination). Syndromes Classic Eagle’s syndrome requires a high degree of suspicion on history. During physical examination, palpation of the tonsillar fossa shows a firm mass beneath the mucosa. This mass is the distal portion of the elongated styloid process with a medial deviation.5 A styloid process that is of average length is not palpable. If an elongated styloid is causing this constellation of symptoms, the symptoms will be reproduced and of greater severity during palpation. Confirmation of the elongated styloid is by radiographic studies. Traditionally, a lateral projection film2z4 measures the length of the process. The posterior-anterior film is valuable in showing any curvature or deviation of the process. Presently, a panoramic radio-
EAGLE’S
SYNDROME
319
Fig 3. Patient 2 with the markings for an external wpreach for resection of the Styloid process.
graph may be used to estimate an elongated styloid’s length. 6 Because of the manner in which a Panarex is obtained, the resulting film has a distorted view of the process. A Panarex may cause an error in measurement of up to of 2 2.5 mm with up to an 11% enlargement the image.‘j A second form of Eagle’s syndrome, known as carotid artery syndrome, is a form of carotidynia. The tip of an elongated styloid process projects between the internal and external carotid arteries. A lateral deviation in its course may cause compression of the external carotid
artery near its bifurcation into the maxillary and superficial temporal arteries.2-5s8 The resulting symptoms of headache or pain will be in the infraorbital, temporal, and mastoid regions.3,6 Patients occasionally complain of tinnitus when turning the head.3 The symptoms are believed to result from compression of the arterial lumen, thus decreasing blood flow, as well as irritation of the sympathetic plexus in the artery’s wa11.3JQ If the elongated styloid deviates posteriorly (toward the retrostyloid compartment of the parapharyngeal space), the internal carotid
Fig 4. The exposed process in patient 2.
styloid
320
artery, the glossopharyngeal nerve, the vagus nerve, the accessory nerve, and the glossopharyngeal nerve may all be affectedq5zg Patients will usually complain of a headache in the distribution of the ophthalmic artery and in the parietal region.3s6 Carotid artery syndrome may be suspected from the history of the patient. Palpation of the styloid process may be either below the mandibular border or in the tonsillar fossa (ie, the tonsil may still be present in this instance). During palpation, the patient will complain of an increase in symptoms. The previously mentioned radiographic studies will show the course of the styloid process. A carotid angiogram may definitively diagnose styloid impingement on the carotid artery system. Eagle’s syndrome has several additional potential sources. The occasional fracture of the styloid process or an ossified stylohyoid ligament may heal improperly.* The resulting inflammatory response may result in irritation of adjacent structures. An insertion tendinitis may occur at the stylohyoid or styloid junction.518 A deviated process may irritate or compress a multitude of cranial nerves, including those in the retrostyloid compartment as well as the lower branches of the trigeminal nerve and the chorda tympani.5Bg Degenerative cervical discopathy with aging may result in a change in the cervical spine with an alteration in the position of the styloid process.5,6j8 Differential diagnosis includes unerupted molars, temporomandibular joint disease, and irritation from dental prosthesis. Tumors in the oropharynx and the hypopharynx may present with many of the same symptoms. Glossopharyngeal neuralgia is more likely to be an acute lancing pain that occurs with swallowing or movement of the tongue. Trigeminal neuralgia (tic doulourex) usually presents with a short, stabbing pain throughout one of the segments of the trigeminal nerve. Patients with sphenopalatine neuralgia typically complain of a persistent aching pain in the region of the eye, cheek, ear, or neck.3,8 Treatment Eagle1 described and advocated a transpharyngeal approach to removal of the elongated portion of the styloid process.lO The patient is intubated, usually nasotracheally. The neck is
RECHTWEG
AND
WAX
hyperextended, and the mouth is suspended open. If the patient has tonsils, they are removed in the preferred fashion of the surgeon. The tonsillar fossa is then palpated for the bony protrusion of the styloid process. A l- to Z-cm vertical incision is made in the mucosa overlying the palpated styloid. The styloid is visualized and grasped at its distal-most point. All muscular and tendinous insertions are sharply removed with a scalpel and periosteal elevator. The process is then grasped proximal to the desired point of resection (a normal styloid is about 25 mm long, and this length could be used as a guide as to how much is removed). A Rongeur is used to resect the bone and smooth the resected edge. The wound is amply irrigated, may be packed with antibiotics, and is closed with interrupted absorbable suture. The transpharyngeal approach is criticized for the potential deep space neck infection and poor visualization of the surgical field. The primary advantages of this approach are the lack of an externally visible scar and the possible avoidance of general anesthesia if the patient has h a d a previous tonsillectomy.8J0 The extraoral approach is considered a superior approach by many surgeons because of the better visualization of the surgical field with its complex anatomy, as well as the decreased risk of a deep space neck infection.8J0 For this approach the patient is orally intubated. The patient has his or her neck hyperextended and rotated to the side opposite the resection. An incision consistent with a Risdon approach or submandibular approach to the mandible may be used. Sharp dissection is used from the skin through the platysma. A combination of blunt and sharp dissection is used to isolate the styloid process. While dissecting down, palpation of the process between the external and internal carotid arteries may be used to guide the course of the dissection. Muscular and ligamentous attachments are removed from the process in the same manner as a transpharyngeal approach. The styloid is then shortened to the appropriate length and the wound is closed. Drainage is not necessary. Although surgery is the workhorse in the treatment of Eagle’s syndrome, nonsurgical therapy may also be attempted. The most common nonsurgical treatments include reas-
EAGLE’S
SYNDROME
surance, nonsteroidal antiinflammatory medications, and steroid injections.5 The overall success rate for treatment, whether it be surgical or not, is in the range of 80%.5 The failure of treatment may be associated with the multifactorial origin of Eagle’s syndrome or because of the difficulty in recognizing the true cause of the symptoms. REFERENCES 1. Eagle Ww: Elongated styloid process: Report of two cases. Arch Otolaryngol25:584-586, 1937 2. Eagle Ww: Elongated styloid process: Further observations and a new syndrome. Arch Otolaryngol 47:630640,1948 3. Eagle Ww: Symptomatic elongated styloid process: Report of two cases of styloid process-Carotid artery syndrome with operation. Arch Otolaryngol 49:499-503, 1949
321
4. Eagle Ww: Elongated styloid process: Symptoms and treatment. Arch Otolaryngol67:172-176,1958 5. Baugh RF, Stocks RM: Eagle’s Syndrome: A reappraisal. Ear Nose Throat J 72:341-344, 1993 6. Keur JJ. Campbell JPS, McCarthy JF, et al: The clinical significance of the elongated styloid process. Oral Surg Oral Med Oral Path 61:399-404,1986 7. Pick TP, Howden R: Grays Anatomy, Descriptive and Surgical (ed 15). Philadelphia, PA, Lippincott, 1977, pp 319-332 8. Strauss M, Zohar Y, Laurian N: Elongated styloid process syndrome: Intraoral versus external approach for styloid surgery. Laryngoscope 95:976-979,1979 9. Heeneman H, Johnson JT, Curtin HD, et al: The Parapharyngeal Space: Anatomy and Pathologic Conditions with Emphasis on Neurogenous Tumors (ed 2). Self Instructional Packet. American Academy of Otolaryngologv-Head and Neck Surgery Foundation Inc, Alexandria, i;;A, 1987,pp l-37 - _ 10. Chase DC. Zarmen A. Bieelow WC. et al: Eaele’s Syndrome: A comparison of intraoral versus extrasral surgical approaches. Oral Surg Oral Med Oral Path 62:625629,1986
A Review
Jay S. Rechtweg, MD, and Mark K. Wax, MD, FACS, FRCS (C)
Demanchetis described a calcified stylohyoid ligament in 1852. * Weinlecher described symptoms related to an elongated styloid process in 1872. He treated the symptoms by removal of the pr0cess.l In the 193Os, Watt W. Eagle of Duke University began to define a syndrome resulting from an elongation of the styloid process .lm4 This syndrome occurred after tonsillectomy and presented as a dull, long-term pain in the throat; occasional globus; dysphagia and headache; and pain that radiated to the ear. In the ensuing years, the term Eagle’s syndrome has become a diagnosis that encompasses a series of conditions resulting from pathologic conditions related to the styloid process. Anatomy
and Embryology
The styloid process is a slender bony projection arising from the lower surface of the petrous portion of the temporal bone. In the fetus this process originates from Reichert’s cartilage of the second brachial arch. This region of Reichert’s cartilage has four separate centers of development: the tympanohyal, the stylohyal, the ceratohyal, and the hypohyal.5s6 The tympanohyal originates at the temporal bone and becomes the base of the styloid process. This region will continue to undergo calcification over the first 8 years of life. The stylohyal becomes the shaft of the styloid process. The degree of calcification of this From the Department of Otolaryngology, Head and Neck Surgery, State University of New York at Buffalo, Buffalo, NY. Address reprint requests to Mark K. Wax, MD, FACS, FRCS (C), Department of Otolaryngology, Head and Neck Surgery, State University of New York at Buffalo, 135 LeBrun Rd, Buffalo, NY 14215. Copyright o 1998 by W.B. Saunders Company 0196-0709/98/l 905-0012$8.00/O 316
American
Journal
of Otolatyngology,
division determines the overall length of the styloid process. The ceratohyal portion becomes the stylohyoid ligament. In many animals this portion may ossify and become a bone referred to as the epihyal.‘jr7 The hypohyal develops into the lesser cornu of the hyoid bone. There have been rare instances where Reichert’s cartilage has failed to undergo the programmed development and has instead developed into a bar of bone extending from the temporal bone to the hyoid bone.5 The styloid process projects inferiorly and anteriorly into the parapharyngeal space.4 In the parapharyngeal space the styloid process is in close proximity to a multitude of structures. The retrostyloid compartment contains the internal jugular vein; the internal carotid artery; the sympathetic chain; and the glossopharyngeal, vagus, accessory, and hypoglossal nerves. The prestyloid compartment contains the internal maxillary artery, the lingual and auricotemporal nerves, and is related to the tonsillar fossa inferiorly. The involvement of some or all of these structures in the parapharyngeal space has been attributed to the origin of the pathologic conditions related to Eagle’s syndrome. Three muscles, the stylopharyngeus, the stylohyoid, and the styloglossus, each with a different innervation, are attached to the styloid process. The stylopharyngeus muscle has its origin at the inner side of the base of the styloid process and inserts into the posterior border of the thyroid cartilage in conjunction with the palatopharyngeus. This muscle pulls the pharynx up and outward during deglutination and is innervated by the glossopharyngeal nerve. The stylohyoid muscle originates at the posterior and lateral portions of the styloid and travels inferiorly and anteriorly to the body of the hyoid bone, adjacent to the greater
Vol 19, No 5 (September-October),
1998:
pp 316-321
EAGLE’S
SYNDROME
cornu. The stylohyoid muscle, in conjunction with the digastric, mylohyoid, and geniohyoid muscles, acts to raise the hyoid bone with the base of the tongue during deglutination. This muscle is innervated by the facial nerve. The styloglossus muscle has its origin on the anterior lateral portion of the styloid process, near its apex. This muscle travels inferiorly and anteriorly to insert into the lateral portion of the tongue. This muscle is one of the extrinsic muscles of the tongue, and as such, is innervated by the hypoglossal nerve. Two ligaments take origin on the styloid process. The stylohyoid ligament, derived from the ceratohyal portion of Reichert’s cartilage, extends from the apex of the styloid ligament to the tip of the lesser cornu of the hyoid bone. The stylomandibular ligament travels from the apex of the styloid process to the posterior border of the mandibular ramus, between the masseter and the ptyergoid muscles. This ligament runs with the styloglossus muscle and acts as an accessory to mandibular articulation. Eagle believed that a normal-length styloid process was about l-in. (2.5 cm) long.3 Moffat, Ramsden, and Shaw have measured the styloid process in 2,000 skulls and 80 postmortem examinations and have determined that the average length of the styloid process varies from 1.52 to 4.77 cm (mean 3.15 cm).8 Stafne and Hollinshead believed the normal length of a styloid process to be 2.0 to 3.0 crne8 The origin of the elongated styloid process is poorly understood. Embryologically, it may be caused by increased calcification of the stylohyal, which resulted in the long body of the styloid process. Furthermore, the ceratohyal and/or the stylohyoid ligament may become ossified. The cause of the ossification may be because of the embryologic potential to differentiate into the epihyal bone or in response to trauma.
317
to have related symptoms. Eagle4 believed that 4% were symptomatic. Kaufman et al found that 10.3% of 68 patients with elongated styloids were symptomatic.5a6 Correll et al found that 7.8% of 103 patients were symptomatic516 Keur et al6 found 53% of women and 40% of men had a symptom that may be related to the styloid (measuring facial pain, tinnitus, odynophagia, and pain when turning the head). The incidence of an elongated styloid process is reported to be between 4% and 28%, with most investigators defining an elongated styloid as being greater than 3 cm in length.‘j Keur et al6 examined 1,135 panoramic radiographs of the mandible in edentulous patients. This group reported that 32.9% of the female and 28.5% of the male patients had elongated styloid processes. They found the average length of the styloid to be 4.79 cm for men (standard deviation of 1.285 cm on the right and 1.328 cm on the left) and 4.45 cm in women on both the right and left sides. CASE REPORTS Patient 1 Patient 1 is a 48-year-old white man who presented to the Otolaryngology Clinic with a chronically enlarged styloid process. Five years before his presentation, he developed right throat pain and odynophagia. Investigation showed an elongated styloid process (Fig 1). This was easily palpated transorally, and he was diagnosed with Eagle’s syndrome. An oral surgeon treated him by fractur-
Incidence Approximately 4% of the population are believed to have an elongated styloid process. With the increased use of the panoramic radiograph for routine dental films, the incidental finding of an elongated styloid is increasing. Only a small percentage of the population with an elongated styloid process is believed
Fig 1. Plain radiograph of the left side of the neck patient 1 showing an elongated styloid process.
of
318
RECHTWEG
ing the styloid process through an intraoral approach. This resolved his pain for 6 months. The resumption of the pain prompted him to seek a second opinion. He was referred to the Otolaryngology Service. After appropriate evaluation, surgical correction of his problem was suggested. The patient underwent an uneventful extraoral resection of a 4.5cm styloid process (Fig 2). He had an overnight hospital admission. With more than 3 years of follow-up, he has had no recurrence of symptoms or any intraoral complaints to date.
Patient 2 A 3 y-year-old white man presented to the Otolaryngology Clinic with a history of progressive dysphagia over the past several years. Approximately 10 years before, he underwent a tonsillectomy. He began to have problems swallowing 5 years before presentation. He was evaluated by a number of specialists with no clear diagnosis until a Panarex radiologic study was performed. The film showed an elongated styloid process. Subsequent physical examination showed the process to be palpable in the tonsillar fossa. During further questioning of the patient, a history of fracturing the styloid was obtained. Conservative therapy relieved his symptoms for a short period of time. When his symptoms returned, surgery was suggested and agreed to by the patient. An external approach to the styloid was undertaken (Figs 3 and 4). A s-cm length of styloid process was removed. He recovered uneventfully. At present, he has had greater than 4 years of follow-up with no noted recurrence of his symptoms.
DISCUSSION Symptoms Classic Eagle’s syndrome occurs in the middle-aged patient at any time after a tonsillectomy. Eagle described: A nagging somewhat
or aching sensation in the throat similar to chronic pharyngitis. ...
2
Fig 2.
The
resected
4
3
styloid
5
process
7
6
of patient
1.
AND
WAX
Pain may radiate to the middle ear or mastoid region. Frequently a sensation of a foreign body having lodged in the pharynx is noticed. There may be difficultyin swallowing.’
Other symptoms associated with this form of Eagle’s syndrome include headache and pain when turning the neck, pain when extending the tongue, change in voice, and a sensation of hypersalivation. w Patients often believe that they have not properly healed from their tonsillectomy. All these symptoms may be considered a form of pharyngeal or neurological irritation. The scarring after a tonsillectomy may lead to contracture of the tonsillar fossa, thus pulling it taut over an elongated styloid process.*-4s8 The pain may be transmitted through the trigeminal nerve, the facial nerve, the glossopharyngeal nerve, or the vagus nerve, all of which provide sensory innervation the pharyngeal mucosa. Furthermore, many of the symptoms may be attributed to the anatomical relation to the styloid process. Pain in the neck when turning the head may be attributed to irritation of any of the nerves in the retrostyloid compartment. Pain when extending the tongue and the odynophagia may be attributed to movement of the musculature and ligaments attached to the styloid process (ie, the styloglossus muscle in relation to tongue protrusion and the stylopharyngeus and stylohyoid muscles and the stylohyoid and stylomandibular ligaments in relation to deglutination). Syndromes Classic Eagle’s syndrome requires a high degree of suspicion on history. During physical examination, palpation of the tonsillar fossa shows a firm mass beneath the mucosa. This mass is the distal portion of the elongated styloid process with a medial deviation.5 A styloid process that is of average length is not palpable. If an elongated styloid is causing this constellation of symptoms, the symptoms will be reproduced and of greater severity during palpation. Confirmation of the elongated styloid is by radiographic studies. Traditionally, a lateral projection film2z4 measures the length of the process. The posterior-anterior film is valuable in showing any curvature or deviation of the process. Presently, a panoramic radio-
EAGLE’S
SYNDROME
319
Fig 3. Patient 2 with the markings for an external wpreach for resection of the Styloid process.
graph may be used to estimate an elongated styloid’s length. 6 Because of the manner in which a Panarex is obtained, the resulting film has a distorted view of the process. A Panarex may cause an error in measurement of up to of 2 2.5 mm with up to an 11% enlargement the image.‘j A second form of Eagle’s syndrome, known as carotid artery syndrome, is a form of carotidynia. The tip of an elongated styloid process projects between the internal and external carotid arteries. A lateral deviation in its course may cause compression of the external carotid
artery near its bifurcation into the maxillary and superficial temporal arteries.2-5s8 The resulting symptoms of headache or pain will be in the infraorbital, temporal, and mastoid regions.3,6 Patients occasionally complain of tinnitus when turning the head.3 The symptoms are believed to result from compression of the arterial lumen, thus decreasing blood flow, as well as irritation of the sympathetic plexus in the artery’s wa11.3JQ If the elongated styloid deviates posteriorly (toward the retrostyloid compartment of the parapharyngeal space), the internal carotid
Fig 4. The exposed process in patient 2.
styloid
320
artery, the glossopharyngeal nerve, the vagus nerve, the accessory nerve, and the glossopharyngeal nerve may all be affectedq5zg Patients will usually complain of a headache in the distribution of the ophthalmic artery and in the parietal region.3s6 Carotid artery syndrome may be suspected from the history of the patient. Palpation of the styloid process may be either below the mandibular border or in the tonsillar fossa (ie, the tonsil may still be present in this instance). During palpation, the patient will complain of an increase in symptoms. The previously mentioned radiographic studies will show the course of the styloid process. A carotid angiogram may definitively diagnose styloid impingement on the carotid artery system. Eagle’s syndrome has several additional potential sources. The occasional fracture of the styloid process or an ossified stylohyoid ligament may heal improperly.* The resulting inflammatory response may result in irritation of adjacent structures. An insertion tendinitis may occur at the stylohyoid or styloid junction.518 A deviated process may irritate or compress a multitude of cranial nerves, including those in the retrostyloid compartment as well as the lower branches of the trigeminal nerve and the chorda tympani.5Bg Degenerative cervical discopathy with aging may result in a change in the cervical spine with an alteration in the position of the styloid process.5,6j8 Differential diagnosis includes unerupted molars, temporomandibular joint disease, and irritation from dental prosthesis. Tumors in the oropharynx and the hypopharynx may present with many of the same symptoms. Glossopharyngeal neuralgia is more likely to be an acute lancing pain that occurs with swallowing or movement of the tongue. Trigeminal neuralgia (tic doulourex) usually presents with a short, stabbing pain throughout one of the segments of the trigeminal nerve. Patients with sphenopalatine neuralgia typically complain of a persistent aching pain in the region of the eye, cheek, ear, or neck.3,8 Treatment Eagle1 described and advocated a transpharyngeal approach to removal of the elongated portion of the styloid process.lO The patient is intubated, usually nasotracheally. The neck is
RECHTWEG
AND
WAX
hyperextended, and the mouth is suspended open. If the patient has tonsils, they are removed in the preferred fashion of the surgeon. The tonsillar fossa is then palpated for the bony protrusion of the styloid process. A l- to Z-cm vertical incision is made in the mucosa overlying the palpated styloid. The styloid is visualized and grasped at its distal-most point. All muscular and tendinous insertions are sharply removed with a scalpel and periosteal elevator. The process is then grasped proximal to the desired point of resection (a normal styloid is about 25 mm long, and this length could be used as a guide as to how much is removed). A Rongeur is used to resect the bone and smooth the resected edge. The wound is amply irrigated, may be packed with antibiotics, and is closed with interrupted absorbable suture. The transpharyngeal approach is criticized for the potential deep space neck infection and poor visualization of the surgical field. The primary advantages of this approach are the lack of an externally visible scar and the possible avoidance of general anesthesia if the patient has h a d a previous tonsillectomy.8J0 The extraoral approach is considered a superior approach by many surgeons because of the better visualization of the surgical field with its complex anatomy, as well as the decreased risk of a deep space neck infection.8J0 For this approach the patient is orally intubated. The patient has his or her neck hyperextended and rotated to the side opposite the resection. An incision consistent with a Risdon approach or submandibular approach to the mandible may be used. Sharp dissection is used from the skin through the platysma. A combination of blunt and sharp dissection is used to isolate the styloid process. While dissecting down, palpation of the process between the external and internal carotid arteries may be used to guide the course of the dissection. Muscular and ligamentous attachments are removed from the process in the same manner as a transpharyngeal approach. The styloid is then shortened to the appropriate length and the wound is closed. Drainage is not necessary. Although surgery is the workhorse in the treatment of Eagle’s syndrome, nonsurgical therapy may also be attempted. The most common nonsurgical treatments include reas-
EAGLE’S
SYNDROME
surance, nonsteroidal antiinflammatory medications, and steroid injections.5 The overall success rate for treatment, whether it be surgical or not, is in the range of 80%.5 The failure of treatment may be associated with the multifactorial origin of Eagle’s syndrome or because of the difficulty in recognizing the true cause of the symptoms. REFERENCES 1. Eagle Ww: Elongated styloid process: Report of two cases. Arch Otolaryngol25:584-586, 1937 2. Eagle Ww: Elongated styloid process: Further observations and a new syndrome. Arch Otolaryngol 47:630640,1948 3. Eagle Ww: Symptomatic elongated styloid process: Report of two cases of styloid process-Carotid artery syndrome with operation. Arch Otolaryngol 49:499-503, 1949
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4. Eagle Ww: Elongated styloid process: Symptoms and treatment. Arch Otolaryngol67:172-176,1958 5. Baugh RF, Stocks RM: Eagle’s Syndrome: A reappraisal. Ear Nose Throat J 72:341-344, 1993 6. Keur JJ. Campbell JPS, McCarthy JF, et al: The clinical significance of the elongated styloid process. Oral Surg Oral Med Oral Path 61:399-404,1986 7. Pick TP, Howden R: Grays Anatomy, Descriptive and Surgical (ed 15). Philadelphia, PA, Lippincott, 1977, pp 319-332 8. Strauss M, Zohar Y, Laurian N: Elongated styloid process syndrome: Intraoral versus external approach for styloid surgery. Laryngoscope 95:976-979,1979 9. Heeneman H, Johnson JT, Curtin HD, et al: The Parapharyngeal Space: Anatomy and Pathologic Conditions with Emphasis on Neurogenous Tumors (ed 2). Self Instructional Packet. American Academy of Otolaryngologv-Head and Neck Surgery Foundation Inc, Alexandria, i;;A, 1987,pp l-37 - _ 10. Chase DC. Zarmen A. Bieelow WC. et al: Eaele’s Syndrome: A comparison of intraoral versus extrasral surgical approaches. Oral Surg Oral Med Oral Path 62:625629,1986