Conternporary eva Iuation of unilateraI vocaI cord paralysis DAVID J. TERRIS, MD, DAVID P. ARNSTEIN, MD, and HENRY H. NGUYEN, MD, Stanford, California
Unilateral vocal cord paralysis is a common finding in the practice of otolaryngology. Multiple etiologies have been described and have not changed appreciably in the last century. We attempted to characterize the contemporary evaluation of unilateral vocal cord paralysis, with consideration given to cost-effectiveness.Thirty-one boardcertified otolaryngologists were interviewed to determine their typical evaluation protocol. The average cost of an evaluation totaled $1706.18, with a range of $112.56 to $3439.52. Otolaryngologists with more years of experience tended to pursue briefer and less expensive evaluations. The charts of 187 patients with a diagnosis of vocal paralysis from 1983 to 1991 were reviewed, of which 113 were evaluable. Eighty-fourof these 113 (74%) were unilateral. In 48 of 84 cases (57%), the cause was apparent at the time of diagnosis. In 36 of 84 cases (43%), an evaluation was necessary. A diagnosis was achieved in 27 of these 36 instances (75%), with the most useful test being a chest roentgenogram (n = 13, 48%). The most common cause of unilateral vocal cord paralysis in our series was neoplasm (n = 34, 40%), followed by surgical trauma (n = 29, 35%). In no instance was a malignancy discovered subsequent to the initial evaluation. The most cost-efficient, inclusive diagnostic evaluation of unilateral vocal cord paralysis involves a stepwise progression through the tests that are most likely to yield a diagnosis, with endoscopy reserved for those cases in which simpler, less invasive tests have not indicated a Cause. (OTOIARYNGOL HEAD NECK SURG 1992;107:84,)
Unilateral vocal cord paralysis (UVCP) is a common problem encountered by the otolaryngologist. There are many reports describing its potential etiologies. I-' Because of the circuitous course of the vagus nerve, especially the recurrent laryngeal nerve (RLN) branch, there are many anatomic areas of vulnerability and numerous diseases that can result in temporary or permanent impairment of vocal cord mobility. Additionally, manifestations differ depending on the level at which the nerve is i n v o l ~ e d . ~ , ~ The most important objective in the evaluation of a patient with UVCP is the determination of the underlying cause. The secondary goal is restoration of vocal cord function, either by reinnervation or medialization.
Despite the increasing societal pressures to control costs and limit medical expenditures, there are no reports in the literature addressing the issue of cost-effectiveness in the evaluation of UVCP. The need exists for an algorithm that guides the otolaryngologist in making sound, comprehensive, yet cost-effective decisions regarding diagnostic tests. Consideration should be given to the yield of these tests, as well as the consequences of delayed diagnosis. We reviewed the hospital medical records of 187 patients with a diagnosis of vocal cord paralysis (VCP) to evaluate the most common etiologies and methods of diagnosis. We then interviewed thirty-one boardcertified otolaryngologists to determine their workup of patients with UVCP of occult origin. We combined these data with a review of the literature to achieve a logical approach for determining the cause of UVCP.
From the Division of Otolaryngology-Head and Neck Surgery, Stanford University Medical Center. Presented at the Annual Meeting of the American Academy of Otolaryngology-Head and Neck Surgery, Kansas City, Mo., Sept. 2226, 1991. Received for publication Oct. 16, 1992; accepted Jan. 10, 1992. Reprint requests: David J. Tenis, MD, Division of OtolaryngologyHead and Neck Surgery ( ~ 1 3 5 ) Stanford . University Medical ten. ter, 300 Pasteur Dr., Stanford, CA 94305. 23 I 1I36344
METHODSAND MATERIALS Patient Analysis
a4
The charts of 187 patients that listed VCP as a diamosis were selected from the medical records at Stan" ford University Medical Center from 1983 to 1991;of these, 113 met the inclusion Criteria. The most common reason for exclusion was lack of adequate documentation of the VCP.
Downloaded from oto.sagepub.com at LAURENTIAN UNIV LIBRARY on April 19, 2016
Volume 107 Number 1 July 1992
Contemporaty evaluation of unilateral vocal cord paralysis
The records were analyzed for patient identification, including name, gender, age, medical record number, date of onset of VCP, method of establishing the existence of VCP, date of diagnosis of etiology (if any), types of diagnostic tests, date and type of treatment, and final outcome.
85
Etiology of UVCP: Stanford Experience (N=84) 10.7%
Physician Interviews
Thirty-one board-certified otolaryngologists were interviewed to determine their usual workup in the evaluation of patients manifesting unilateral vocal cord paralysis, no history of recent head and neck surgery, and no other obvious findings on physical examination. Personal data obtained included place of training, year of completion of training, and number of years of otolaryngology experience (including training). The 1990 costs of all studies requested in the physician poll were obtained from the Stanford Patient Services division. From these costs, the total expense of the usual evaluations for each physician interviewed was computed. Statistical analysis was performed using the Student r-test.
40.5%
RESULTS Patient Analysis
Neoplasm
There were 84 patients (74.3%) with UVCP and 29 patients (25.7%) with bilateral VCP. Only the data from the patients with UVCP were analyzed. Among this group, there were 45 men (53.6%) and 39 women (46.4%). The age at onset ranged from 20 to 91 years, with a mean of 58.0 years. The left cord was affected in 57 cases (67.9%), and the right cord in 27 cases (32.1%). The interval from time of diagnosis to time of treatment in the 34 patients who received treatment ranged from 1 month to 9 years, with a mean of 24.4 months. As seen in Fig. I. the most common etiologies for UVCP were neoplasm ( n = 34, 40.5%), which included 14 cases of lung cancer, and surgery ( n = 29, 34.5%), which included seven cases of thyroid surgery. Other common etiologies were trauma (n = 7, 8.3%), six of which were induced by intubation; others had medical or inflammatory causes ( n = 3, 3.6%). There were two cases (2.4%) attributed to central causes. There were nine cases of idiopathic paralysis (10.7%). In many of the cases ( n = 48,57.1%) the cause was apparent at the time of diagnosis (for example, postsurgical, or metastasis from a known primary cancer). In the remaining 36 cases (42.9%), an evaluation was necessary. A diagnosis was achieved in 27 (75%) of these 36 instances. Among these 27 cases in which a diagnosis was achieved, neoplasm was responsible in 23 patients (85.2%), and 13 of these neoplasms were
Post-Surgical Trauma Medical/lnflammatory
0
Central Idiopathic
Fig.1. Frequency of etiologies of unilateral vocal cord paralysis in 84 Datients at Stanford.
Table 1. Yield (percentage of tests ordered that achieved a diagnosis) of various tests were computed, drawn from the group of patients in which a workup was required (N = 36)
Diagnostic test ~~~~
No. of tests ordered ~
MRI scan Chest x-ray CT scan Endoscopy Barium swallow TFTs Skull series Thyroid scan TFTs, Thyroid function tests
Downloaded from oto.sagepub.com at LAURENTIAN UNIV LIBRARY on April 19, 2016
No. of diagnoses achieved
Yield
1%)
~
5 24 20 5 10 2 2 1
3 13 7 1 0 0 0 0
60 54 2
35 20 0 0
0 0
OtolaryngologyHead and Neck Surgery
86 TERRIS et a1
Correlation of Experience with Expense of Evaluation 4000
r
h
Kl -
3000 v
Q)
cn
c
g
2000
X
w c 0 .c. Kl
Kl > w
1000
3
0 0
5
15
10
20
25
30
35
40
45
50
Otolaryngology Experience (Years) Fig. 2. Evaluation expense (dollars) compared with the experience (years] of the otolaryngologists (N= 31).
Evaluation Expense:
4 versus >25 Years of Experience 3000 ;=$2270.91f1047.92
h
v)
z -
8
2000
a, v)
S
a,
2 .-5 W
1000
c
N=5 ?=$306.99+147.39
(II
3 (d
>
W
0
25
Otolaryngology Experience (Years) Fig. 3. The expense of workup of 14 younger otolaryngologists was compared with that of 5 more experienced otolaryngologists,and found to have a significant difference ( p < 0.001).
was detected. When the ability of a specific test to lung cancers. A chest roentgenogram was the most useful test in this group of patients, yielding the diagnosis achieve a diagnosis was considered, the yield (number of diagnoses divided by the number of tests ordered) in 13 cases (48.1%); this was followed by CT scanning of the tests ranged from 60% for MRI, to 0% for barium (seven cases, 25.9%). Sixteen endoscopies were perDownloaded from oto.sagepub.com at LAURENTIAN UNIV LIBRARY on April 19, 2016 swallow, thyroid function tests, thyroid scan, and skull formed, and one previously undiagnosed lung cancer
Volume 107 Number 1 July 1992
Contemporary evaluation of unilateral vocal cord paralysis 87
Table 2. Tabulation of frequency of causes of unilateral vocal cord paralysis in eight published series, including our own Total no.
Neoplasms
Of
(lung
Author(s),year
patients
cancer]
Parnell and Brandenburg, 1970 Maisel and Ogura, 1974
100
2
17
7
10
181
33
19
14
36
Titche, 1976
134
15
30
21
3
Kearsley, 1981
100
0
13
6
15
Barondess et al.. 1985
121
0
14
6
22
Willatt and Stell, 1989
155
3
18
0
42
Ojawa et al., 1990
144
1
21
5
9
Terris et al., 1991 (present study) TOTALS
Surgical (thyroidectomy) Trauma
84
-
14)
1019
365
(7) 25 1
SurgicalIinflammatory
Central Idiopathic
7
3
2
61
-
61
135
9
146
these 2 1 , five were magnetic resonance imaging (MRI) and 16 were CT scans. Seven otolaryngologists (23%) recommended panendoscopy. Other tests recommended included serum glucose level (n = 8, 26%), erythrocyte sedimentation rate ( n = 8, 26%), complete blood count ( n = 7, 23%), chemistry panel (n = 5, 16%), thyroid function tests ( n = 5 , 16%), barium swallow Physician Interviews (n = 4 , 13%), thyroid scan ( n = 3, lo%), and then isolated recommendations of skull x-rays, Epstein-Barr Thirty-one of thirty-one otolaryngologists contacted virus titers, and an audiogram. The cost of the studies participated in the survey. Fourteen of the otolarynthat were mentioned among the interviewed otolaryngologists trained at Stanford. Of the remaining 17 phygologists (excluding panendoscopy) ranged from sicians, six trained on the West Coast, six trained on $16.08 for an FTA-ABS to $2815 for a CT from base the East Coast, four trained in the Midwest, and there of skull to mediastinum. was one Singapore-trained otolaryngologist. There The cost for the evaluations recommended (excluding were 26 men, and 5 women. The mean length of otopanendoscopy) ranged from $1 12.56 to $3672.63, with laryngology experience was 15.7 years, with a range a mean of $1706.18 k $1137.82 (see Fig. 2). The of 4 to 44 years. Fourteen had completed their training expense of panendoscopy varies from approximately within the past 5 years, 19 within the last 10 years. $2500 to $3500, including surgeon's fees, anaesthesia Five had completed their training more than 25 years fees, and hospital costs, assuming discharge on the day before the interview. of surgery. There was a wide range in the breadth of evaluation When the group of physicians who finished their recommended, from simply a chest roentgenogram training in the past 5 years was compared to those who (n = 3) to one physician's advocacy of a lengthy infinished more than 25 years ago, 12 of the 14 younger vestigation comprising chest roentgenogram, computphysicians (86%) desired advanced imaging studies erized tomography from base of skull to mediastium, compared with none (0 of 5) of the more experienced lumbar puncture, glucose tolerance test, complete blood otolaryngologists. The difference in mean cost of evalcount, VDRL, erythrocyte sedimentation rate, urinaluation between the 14 younger and five older physicians ysis, and thyroid scan. The most commonly ordered was highly statistically significant: $2270.91 ? study was a chest roentgenogram ( n = 25, 81%). The 1047.92 vs. $306.99 +- 147.39, respectively; p < second most commonly ordered examination was an Downloaded from oto.sagepub.com at LAURENTIAN UNIV LIBRARY on April 19, 2016 0.001 (see Fig. 3). advanced imaging examination ( n = 2 1 , 68%). Of series. Chest x-ray, CT, and endoscopy had intermediate yields of 54.2%, 35%, and 20% respectively. These data are summarized in Table 1. Overall, a diagnosis was achieved in 75 of 84 cases (89.3%), whereas nine of 84 (10.7%) remained idiopathic.
OtolaryngologyHead and Neck Surgery
88 TERRIS et 01
Etiology of UVCP: Combined ExDerience (N=l019) 14.3%
35.8%
comprising 55.4% of these. Six percent were central, 13.3% resulted from inflammatory or medical causes, and 6% resulted from trauma. The idiopathic group comprised 14.3%. When compared with the literature, our series showed a slightly higher incidence of neoplasm as the cause of UVCP, and surgical trauma was also somewhat more common. The medical and inflammatory causes were significantly less common, and the remainder of the categories had comparable representation. DISCUSSION
13
24.6%
Neoplasm Post-Su rgical Trauma MedicaVlnflammatory
0
Central Idiopathic
Fig. 4. Frequency of etiologies of unilateral vocal cord paralysis in 1019 patients reviewed from the literature (1970 to 1991)’ and from the Stanford experience.
Review of the literature
Review of the literature yielded seven manuscripts from 1970 to 1991 in which the causes of vocal cord paralysis were sufficiently delineated for evaluation. I-’ These were adapted to the categories discussed earlier and are shown in Table 2, which includes our own experience. These data are summarized in Fig. 4. There was a total of 1019 patients. More than one third of the cases of vocal cord paralysis (35.8%) resulted from neoplasm, underscoring the need for careful evaluation. Of these, 54.8% were lung cancer. One fourth (24.6%) were post-surgical, with thyroid surgery
The patient with unilateral vocal cord paralysis continues to commonly present a diagnostic dilemma to the contemporary otolaryngologist. As discussed earlier, there are many potential etiologies. I-’ In evaluating the cause of UVCP of unknown origin, underlying disease processes or malignant conditions must be ruled out. With the advent of advanced imaging studies of the head an neck (CT and MRI), it is now possible to image the entire course of the laryngeal nerves. When these imaging methods are available, they obviate the need for such tests as thyroid scans, thyroid function tests, plain films of the base of skull, and esophagrams. Elimination of such studies not only saves expense, but time and potential morbidity to the patient as well. As demonstrated by Ward et al.,’ it is sometimes possible to distinguish RLN paralysis from high vagus nerve paralysis with a videolaryngeal examination. This localization allows the diagnostician to direct his efforts toward either the skull base (in the case of proximal lesions), or the neck and chest (for lesions distal to the nodose ganglion). Consideration of the side of the paralysis is also important because left-sided lesions require careful examination of the mediastinum. We have listed the causes of vocal cord paralysis that were encountered in 84 Stanford patients (Fig. 1). These data are comparable to those found in the literature (Table 2 and Fig. 4). The most common cause of unilateral paralysis according to most reports is neoplasm, especially lung cancer. This is followed closely by surgical trauma, particularly thyroidectomy. Idiopathic paralysis continues to be a common finding. With the knowledge of the common causes of VCP, a logical approach to diagnosis can be made. A thorough history and physical examination, including flexible office endoscopy, are a prerequisite to any diagnostic studies. The nasopharyngoscope not only allows careful, comfortable inspection of the vocal cords, but also enables palpation of the supraglottic larynx, to assess the integrity of the superior laryngeal nerves.
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Volume 107 Number 1 July 1992
Contemporary evaluation of unilateral vocal cord paralysis 89
The most important objective in evaluation of a patient with vocal cord paralysis is exclusion of the existence of a treatable, potentially life-threatening primary cause of the condition. A chest x-ray film remains a useful screening study; however, its limitations must be recognized. Glazer et al.'" demonstrated that of 18 mediastinal masses seen on CT scan, only five were seen on plain film. Advanced imaging studies such as the CT scan and MRI are now available at a moderate cost. The CT scan is a very sensitive study for lesions in the neck and upper chest and is accessible in most communities. The MRI offers improved resolution, especially in the brainstem and skull base, and requires no exposure to ionizing radiation. " Although controversy persists, the current radiologic literature suggests that when MRI is available, it is more suitable for diagnosing pulmonary and mediastinal lesions that are likely to be associated with VCP,'2-'4and it is gaining increasing acceptance in the diagnosis of lesions of the head and neck." There appears to be no need for obtaining such studies as an erythrocyte sedimentation rate, VDRL, glucose level, complete blood count, urinalysis, chemistry profile, or thyroid function studies. The total cost of these simple laboratory tests at Stanford Medical Center in 1990 was $387.76. The diseases revealed by these tests are very rarely responsible for VCP, and usually the diagnosis is already known at the time of development of VCP. When CT or MRI are used, the need for a thyroid scan ($495) and barium swallow ($292) is also obviated. Endoscopy remains a valuable diagnostic tool, both for elimination of the possibility of an occult cancer and for establishment of cricoarytenoid (CA) joint mobility. Alternatively, CA joint fixation can be inferred if electromyography demonstrates action potentials despite lack of vocal cord movement. l 6 Our investigation shows that there is a large amount of variability in the diagnostic practices of otolaryngologists, even those grouped in a relatively small geographic area and from largely similar training backgrounds. It was interesting to note the trend toward use of advanced imaging studies among the younger physicians and also the broader workup in this group. Otolaryngologists should adopt a uniform approach to UVCP. A chest roentgenogram remains a very useful study; it should be followed by MR imaging of the neck if the paralysis occurs on the right side, and MR imaging of the neck down to the arch of the aorta if the paralysis is on the left side. CT scanning remains an excellent alternative. If these tests are unrevealing, endoscopy
(including bronchoscopy, esophagoscopy, and direct laryngoscopy) should be performed. CONCLUSIONS 1. There continues to be much variability among the
diagnostic practices of otolaryngologists who evaluate patients with VCP of unknown origin. Younger physicians tend to expend more resources in the course of their evaluation than physicians with greater experience. 2 The advent of advanced imaging tests (MRI and CT) allows a comprehensive search for occult causes of VCP; these tests are readily obtainable, relatively inexpensive, and produce little morbidity to the patient. 3 A cost-effective, medically sound approach to the patient with UVCP of unknown origin includes a chest roentgenogram followed by an MRI or CT. The areas to be scanned depend on the side of the paralysis: for left UVCP, scan the neck to the aorta; for right UVCP, scan the neck. If these tests are unrevealing, panendoscopy should be performed. 4. There is little yield from ordering screening laboratory tests such as complete blood count, chemistry panel, urinalysis, VDRL, or FTA-ABS, thyroid function tests, or erythrocyte sedimentation rate. These tests should not routinely be ordered. Additionally, when either CT or MRI imaging is used, thyroid scans and barium swallows are unnecessary. We would like to thank Martha K. Terris, MD, for her careful editorial assistance with this manuscript. REFERENCES
I . Parnell FW, Brandenburg JH. Vocal cord paralysis: a review of 100 cases. Laryngoscope 1970;XO: 1036-45. 2. Maisel RH, Ogura JH. Evaluation and treatment of vocal cord paralysis. Laryngoscope 1974;84:302-16. 3. Titche LL. Causes of recurrent laryngeal nerve paralysis. Arch Otolaryngol 1976;102:259-61. 4. Kearsley JH. Vocal cord paralysis-an etiologic review of 100 cases over 20 years. Aust N Z J Med 1981;11:663-6. 5. Barondess JA, Pompei P, Schley WS. A study of vocal cord palsy. Trans Am Clin Climatol Assoc 1985;97:141-8. 6. Willatt DJ, Stell PM. The prognosis and management of idiopathic vocal cord paralysis. Clin Otolaryngol 1989;14:247-50. 7. Ojawa Y, Takashi M , Hiroshi M. Recurrent laryngeal nerve paralysis. In: Sacristan T. Alvarez-Vicent JJ, Bartual J, et al., eds. Otorhinolaryngol Head Neck Surg. Amsterdam: Kugler & Ghedini Publications, I990:202 1-4. 8. Bevan K, Griffiths MV. Morgan MH. Cricothyroid muscle paralysis: its recognition and diagnosis. J Laryngol Otol 1989;103:I9 1-5.
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90 TERRIS et ol
9. Ward PH, Berci G. Observations on so-called idiopathic vocal cord paralysis. Ann Otol Rhino1 Laryngol 1982;91:558-63. 10. Glazer HS, Aronberg DJ, Lee JKT, Sagel SS. Extralaryngeal causes of vocal cord paralysis: CT evaluation. AJR 1983;141:527-31. 11. Jacobs CJ, Harnsberger HR, Lutkin RB, Osborn AG, Smoker WR, Parkin JL. Vagal neuropathy: evaluation with CT and MR imaging. Radiology 1987;164:97-102, 12. Webb WR, Jensen BG, Sollitto R, et al. Bronchogenic carcinoma: staging with MR compared with staging with CT and surgery. Radiology 1985;156:117-24.
13. Epstein DM, Kressel H, Gefter W, et al. MR imaging of the mediastinum: a retrospective comparison with computed tomography. J Comp Assist Tomogr 1984;8:670-6. 14. Heelan RT, Martini N. Westcott JW, et al. Carcinomatour involvement of the hilum and mediastinum: computed tomographic and magnetic resonance evaluation. Radiology 1985;156:111-5. 15. Lufkin RB, Hanafee W. Magnetic resonance imaging of head and neck tumors. Cancer Metastasis Rev 1988;7: 19-38. 16. Miller RH, Rosenfield DB. The role of electromyography in clinical laryngology. OTOLARYNGOL HEADNECK SURC1984; 92:287-91.
AVAILABLE NOW! The FIVE-YEAR (1986-1990) CUMULATIVE INDEX TO OTOLARYNGOLOGY -HEAD AND NECK SURGERY can be purchased from the Publisher for $44.00. This comprehensive 104-page reference guide is a current presentation of all topics included in the Journal from January 1986 through December 1990 (volumes 94103)-the past 10 volumes. It incorporates complete references to more than 640 original articles, abstracts, case reports, letters, and editorials. It features 1668 Subject Headings, under which there are 3247 references. Each subject entry lists the complete article title, author(s), volume, page(s), and year of publication. In addition, it includes 3190 Author Entries, which list contributors, along with their respective titles, author-to-author referral, volume, page, and publication. To purchase, call or write: Mosby-Year Book, Inc., 11830 Westline Industrial Dr., St. Louis, Missouri 63146-3318, or telephone FREE 1-800-325-4177, extension 4351, Journal Fulfillment (in Missouri, call collect at 3 14-872-8370, extension 435 I , Journal Fulfillment). PREPAYMENT REQUIRED. Make checks payable to Mosby-Year Book, Inc.; (all payments must be in U.S. funds drawn on a U.S. bank). Price: $44.00 in the U.S.; $50.50 in Canada; and $48.50 in other countries (price includes mailing charges).
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310
Otolaryngology Head and Neck Surgery March 1993
News and Announcements
held July 26-30, 1993, at the Tamarron Resort in Durango, Colorado. This 28 hour review and update will encompass all the clinically important areas of MR imaging. Important new concepts and pathological/imaging correlations in the body, musculoskeletal system, ENT, head and neck, brain, and spine will be explored. Daily case presentations will supplement these lectures and will serve to test the registrants' diagnostic abilities in MR imaging. This complete review of MR imaging will be presented by nationally recognized leaders in magnetic resonance imaging. As a result of this comprehensive review, registrants will become familiar with current applications of MR imaging and will be able to integrate many of these applications directly into their practice. Program chairmen for this presentation will be Robert Quencer, MD (University of Miami), Victor Haughton, MD (Medical College of Wisconsin). Twenty-eight credits of Category I will be available. For further information, please contact Marti Carter, CME, Inc., 11011 West Nort Ave., Milwaukee, Wisconsin 53226, or call (414) 771-9520. Ear, Nose, and Throat Diseases: 1993 Update
Children's Hospital of Pittsburgh will hold its 18th Annual Symposium, "Ear, Nose, and Throat Diseases in Children: A 1993 Update." This symposium will be held July 30-31, 1993. CME credits will be awarded.
For further information, please contact the Department of Pediatric Otolaryngology, Children's Hospital of Pittsburgh, 3705 Fifth Avenue at DeSoto St., Pittsburgh, Pennsylvania 15213, or call (412) 692-8577. Twenty-fifth Annual Meeting - Head and Neck Oncologists
The Association of Head and Neck Oncologists of Great Britain will sponsor the Twenty-fifth Annual Meeting of Head and Neck Oncology, to be held in Edinburgh, Scotland, United Kingdom, on August 23-26, 1993. International and local faculty will present extensive social and family programs. For further information, please contact Mr. P. J. Bradley, Honorary Secretary, Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital, Queens Medical Centre, Nottingham, NG7 2UH, England, or phone 0602421421. Sixth International Congress on Interventlonal Ultrasound
The Sixth International Congress on Interventional Ultrasound will be held in Copenhagen, Denmark, on September 7-10, 1993. For further information, please contact Christian Nolsoe, Congress Secretary, Department of Ultrasound, Herlev Hospital, University of Copenhagen, DK-2730 HerlevDenmark, or call + 45/ 44 53 53 00 ext. 3240.
CORRECTION
The Supplement to the December 1992 issue of the JOURNAL (Volume 107, Number 6, Part 2), incorrectly listed Dr. Bruce R. Gordon as Chief of Otolaryngology at the Massachusetts Eye and Ear Institute. Dr. Joseph Nadol is Chief of Otolaryngology at the Massachusetts Eye and Ear Infirmary. Dr. Gordon is Chief of Otolaryngology at Cape Cod Hospital.
Unilateral vocal cord paralysis is a common finding in the practice of otolaryngology. Multiple etiologies have been described and have not changed appreciably in the last century. We attempted to characterize the contemporary evaluation of unilateral vocal cord paralysis, with consideration given to cost-effectiveness.Thirty-one boardcertified otolaryngologists were interviewed to determine their typical evaluation protocol. The average cost of an evaluation totaled $1706.18, with a range of $112.56 to $3439.52. Otolaryngologists with more years of experience tended to pursue briefer and less expensive evaluations. The charts of 187 patients with a diagnosis of vocal paralysis from 1983 to 1991 were reviewed, of which 113 were evaluable. Eighty-fourof these 113 (74%) were unilateral. In 48 of 84 cases (57%), the cause was apparent at the time of diagnosis. In 36 of 84 cases (43%), an evaluation was necessary. A diagnosis was achieved in 27 of these 36 instances (75%), with the most useful test being a chest roentgenogram (n = 13, 48%). The most common cause of unilateral vocal cord paralysis in our series was neoplasm (n = 34, 40%), followed by surgical trauma (n = 29, 35%). In no instance was a malignancy discovered subsequent to the initial evaluation. The most cost-efficient, inclusive diagnostic evaluation of unilateral vocal cord paralysis involves a stepwise progression through the tests that are most likely to yield a diagnosis, with endoscopy reserved for those cases in which simpler, less invasive tests have not indicated a Cause. (OTOIARYNGOL HEAD NECK SURG 1992;107:84,)
Unilateral vocal cord paralysis (UVCP) is a common problem encountered by the otolaryngologist. There are many reports describing its potential etiologies. I-' Because of the circuitous course of the vagus nerve, especially the recurrent laryngeal nerve (RLN) branch, there are many anatomic areas of vulnerability and numerous diseases that can result in temporary or permanent impairment of vocal cord mobility. Additionally, manifestations differ depending on the level at which the nerve is i n v o l ~ e d . ~ , ~ The most important objective in the evaluation of a patient with UVCP is the determination of the underlying cause. The secondary goal is restoration of vocal cord function, either by reinnervation or medialization.
Despite the increasing societal pressures to control costs and limit medical expenditures, there are no reports in the literature addressing the issue of cost-effectiveness in the evaluation of UVCP. The need exists for an algorithm that guides the otolaryngologist in making sound, comprehensive, yet cost-effective decisions regarding diagnostic tests. Consideration should be given to the yield of these tests, as well as the consequences of delayed diagnosis. We reviewed the hospital medical records of 187 patients with a diagnosis of vocal cord paralysis (VCP) to evaluate the most common etiologies and methods of diagnosis. We then interviewed thirty-one boardcertified otolaryngologists to determine their workup of patients with UVCP of occult origin. We combined these data with a review of the literature to achieve a logical approach for determining the cause of UVCP.
From the Division of Otolaryngology-Head and Neck Surgery, Stanford University Medical Center. Presented at the Annual Meeting of the American Academy of Otolaryngology-Head and Neck Surgery, Kansas City, Mo., Sept. 2226, 1991. Received for publication Oct. 16, 1992; accepted Jan. 10, 1992. Reprint requests: David J. Tenis, MD, Division of OtolaryngologyHead and Neck Surgery ( ~ 1 3 5 ) Stanford . University Medical ten. ter, 300 Pasteur Dr., Stanford, CA 94305. 23 I 1I36344
METHODSAND MATERIALS Patient Analysis
a4
The charts of 187 patients that listed VCP as a diamosis were selected from the medical records at Stan" ford University Medical Center from 1983 to 1991;of these, 113 met the inclusion Criteria. The most common reason for exclusion was lack of adequate documentation of the VCP.
Downloaded from oto.sagepub.com at LAURENTIAN UNIV LIBRARY on April 19, 2016
Volume 107 Number 1 July 1992
Contemporaty evaluation of unilateral vocal cord paralysis
The records were analyzed for patient identification, including name, gender, age, medical record number, date of onset of VCP, method of establishing the existence of VCP, date of diagnosis of etiology (if any), types of diagnostic tests, date and type of treatment, and final outcome.
85
Etiology of UVCP: Stanford Experience (N=84) 10.7%
Physician Interviews
Thirty-one board-certified otolaryngologists were interviewed to determine their usual workup in the evaluation of patients manifesting unilateral vocal cord paralysis, no history of recent head and neck surgery, and no other obvious findings on physical examination. Personal data obtained included place of training, year of completion of training, and number of years of otolaryngology experience (including training). The 1990 costs of all studies requested in the physician poll were obtained from the Stanford Patient Services division. From these costs, the total expense of the usual evaluations for each physician interviewed was computed. Statistical analysis was performed using the Student r-test.
40.5%
RESULTS Patient Analysis
Neoplasm
There were 84 patients (74.3%) with UVCP and 29 patients (25.7%) with bilateral VCP. Only the data from the patients with UVCP were analyzed. Among this group, there were 45 men (53.6%) and 39 women (46.4%). The age at onset ranged from 20 to 91 years, with a mean of 58.0 years. The left cord was affected in 57 cases (67.9%), and the right cord in 27 cases (32.1%). The interval from time of diagnosis to time of treatment in the 34 patients who received treatment ranged from 1 month to 9 years, with a mean of 24.4 months. As seen in Fig. I. the most common etiologies for UVCP were neoplasm ( n = 34, 40.5%), which included 14 cases of lung cancer, and surgery ( n = 29, 34.5%), which included seven cases of thyroid surgery. Other common etiologies were trauma (n = 7, 8.3%), six of which were induced by intubation; others had medical or inflammatory causes ( n = 3, 3.6%). There were two cases (2.4%) attributed to central causes. There were nine cases of idiopathic paralysis (10.7%). In many of the cases ( n = 48,57.1%) the cause was apparent at the time of diagnosis (for example, postsurgical, or metastasis from a known primary cancer). In the remaining 36 cases (42.9%), an evaluation was necessary. A diagnosis was achieved in 27 (75%) of these 36 instances. Among these 27 cases in which a diagnosis was achieved, neoplasm was responsible in 23 patients (85.2%), and 13 of these neoplasms were
Post-Surgical Trauma Medical/lnflammatory
0
Central Idiopathic
Fig.1. Frequency of etiologies of unilateral vocal cord paralysis in 84 Datients at Stanford.
Table 1. Yield (percentage of tests ordered that achieved a diagnosis) of various tests were computed, drawn from the group of patients in which a workup was required (N = 36)
Diagnostic test ~~~~
No. of tests ordered ~
MRI scan Chest x-ray CT scan Endoscopy Barium swallow TFTs Skull series Thyroid scan TFTs, Thyroid function tests
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No. of diagnoses achieved
Yield
1%)
~
5 24 20 5 10 2 2 1
3 13 7 1 0 0 0 0
60 54 2
35 20 0 0
0 0
OtolaryngologyHead and Neck Surgery
86 TERRIS et a1
Correlation of Experience with Expense of Evaluation 4000
r
h
Kl -
3000 v
Q)
cn
c
g
2000
X
w c 0 .c. Kl
Kl > w
1000
3
0 0
5
15
10
20
25
30
35
40
45
50
Otolaryngology Experience (Years) Fig. 2. Evaluation expense (dollars) compared with the experience (years] of the otolaryngologists (N= 31).
Evaluation Expense:
4 versus >25 Years of Experience 3000 ;=$2270.91f1047.92
h
v)
z -
8
2000
a, v)
S
a,
2 .-5 W
1000
c
N=5 ?=$306.99+147.39
(II
3 (d
>
W
0
25
Otolaryngology Experience (Years) Fig. 3. The expense of workup of 14 younger otolaryngologists was compared with that of 5 more experienced otolaryngologists,and found to have a significant difference ( p < 0.001).
was detected. When the ability of a specific test to lung cancers. A chest roentgenogram was the most useful test in this group of patients, yielding the diagnosis achieve a diagnosis was considered, the yield (number of diagnoses divided by the number of tests ordered) in 13 cases (48.1%); this was followed by CT scanning of the tests ranged from 60% for MRI, to 0% for barium (seven cases, 25.9%). Sixteen endoscopies were perDownloaded from oto.sagepub.com at LAURENTIAN UNIV LIBRARY on April 19, 2016 swallow, thyroid function tests, thyroid scan, and skull formed, and one previously undiagnosed lung cancer
Volume 107 Number 1 July 1992
Contemporary evaluation of unilateral vocal cord paralysis 87
Table 2. Tabulation of frequency of causes of unilateral vocal cord paralysis in eight published series, including our own Total no.
Neoplasms
Of
(lung
Author(s),year
patients
cancer]
Parnell and Brandenburg, 1970 Maisel and Ogura, 1974
100
2
17
7
10
181
33
19
14
36
Titche, 1976
134
15
30
21
3
Kearsley, 1981
100
0
13
6
15
Barondess et al.. 1985
121
0
14
6
22
Willatt and Stell, 1989
155
3
18
0
42
Ojawa et al., 1990
144
1
21
5
9
Terris et al., 1991 (present study) TOTALS
Surgical (thyroidectomy) Trauma
84
-
14)
1019
365
(7) 25 1
SurgicalIinflammatory
Central Idiopathic
7
3
2
61
-
61
135
9
146
these 2 1 , five were magnetic resonance imaging (MRI) and 16 were CT scans. Seven otolaryngologists (23%) recommended panendoscopy. Other tests recommended included serum glucose level (n = 8, 26%), erythrocyte sedimentation rate ( n = 8, 26%), complete blood count ( n = 7, 23%), chemistry panel (n = 5, 16%), thyroid function tests ( n = 5 , 16%), barium swallow Physician Interviews (n = 4 , 13%), thyroid scan ( n = 3, lo%), and then isolated recommendations of skull x-rays, Epstein-Barr Thirty-one of thirty-one otolaryngologists contacted virus titers, and an audiogram. The cost of the studies participated in the survey. Fourteen of the otolarynthat were mentioned among the interviewed otolaryngologists trained at Stanford. Of the remaining 17 phygologists (excluding panendoscopy) ranged from sicians, six trained on the West Coast, six trained on $16.08 for an FTA-ABS to $2815 for a CT from base the East Coast, four trained in the Midwest, and there of skull to mediastinum. was one Singapore-trained otolaryngologist. There The cost for the evaluations recommended (excluding were 26 men, and 5 women. The mean length of otopanendoscopy) ranged from $1 12.56 to $3672.63, with laryngology experience was 15.7 years, with a range a mean of $1706.18 k $1137.82 (see Fig. 2). The of 4 to 44 years. Fourteen had completed their training expense of panendoscopy varies from approximately within the past 5 years, 19 within the last 10 years. $2500 to $3500, including surgeon's fees, anaesthesia Five had completed their training more than 25 years fees, and hospital costs, assuming discharge on the day before the interview. of surgery. There was a wide range in the breadth of evaluation When the group of physicians who finished their recommended, from simply a chest roentgenogram training in the past 5 years was compared to those who (n = 3) to one physician's advocacy of a lengthy infinished more than 25 years ago, 12 of the 14 younger vestigation comprising chest roentgenogram, computphysicians (86%) desired advanced imaging studies erized tomography from base of skull to mediastium, compared with none (0 of 5) of the more experienced lumbar puncture, glucose tolerance test, complete blood otolaryngologists. The difference in mean cost of evalcount, VDRL, erythrocyte sedimentation rate, urinaluation between the 14 younger and five older physicians ysis, and thyroid scan. The most commonly ordered was highly statistically significant: $2270.91 ? study was a chest roentgenogram ( n = 25, 81%). The 1047.92 vs. $306.99 +- 147.39, respectively; p < second most commonly ordered examination was an Downloaded from oto.sagepub.com at LAURENTIAN UNIV LIBRARY on April 19, 2016 0.001 (see Fig. 3). advanced imaging examination ( n = 2 1 , 68%). Of series. Chest x-ray, CT, and endoscopy had intermediate yields of 54.2%, 35%, and 20% respectively. These data are summarized in Table 1. Overall, a diagnosis was achieved in 75 of 84 cases (89.3%), whereas nine of 84 (10.7%) remained idiopathic.
OtolaryngologyHead and Neck Surgery
88 TERRIS et 01
Etiology of UVCP: Combined ExDerience (N=l019) 14.3%
35.8%
comprising 55.4% of these. Six percent were central, 13.3% resulted from inflammatory or medical causes, and 6% resulted from trauma. The idiopathic group comprised 14.3%. When compared with the literature, our series showed a slightly higher incidence of neoplasm as the cause of UVCP, and surgical trauma was also somewhat more common. The medical and inflammatory causes were significantly less common, and the remainder of the categories had comparable representation. DISCUSSION
13
24.6%
Neoplasm Post-Su rgical Trauma MedicaVlnflammatory
0
Central Idiopathic
Fig. 4. Frequency of etiologies of unilateral vocal cord paralysis in 1019 patients reviewed from the literature (1970 to 1991)’ and from the Stanford experience.
Review of the literature
Review of the literature yielded seven manuscripts from 1970 to 1991 in which the causes of vocal cord paralysis were sufficiently delineated for evaluation. I-’ These were adapted to the categories discussed earlier and are shown in Table 2, which includes our own experience. These data are summarized in Fig. 4. There was a total of 1019 patients. More than one third of the cases of vocal cord paralysis (35.8%) resulted from neoplasm, underscoring the need for careful evaluation. Of these, 54.8% were lung cancer. One fourth (24.6%) were post-surgical, with thyroid surgery
The patient with unilateral vocal cord paralysis continues to commonly present a diagnostic dilemma to the contemporary otolaryngologist. As discussed earlier, there are many potential etiologies. I-’ In evaluating the cause of UVCP of unknown origin, underlying disease processes or malignant conditions must be ruled out. With the advent of advanced imaging studies of the head an neck (CT and MRI), it is now possible to image the entire course of the laryngeal nerves. When these imaging methods are available, they obviate the need for such tests as thyroid scans, thyroid function tests, plain films of the base of skull, and esophagrams. Elimination of such studies not only saves expense, but time and potential morbidity to the patient as well. As demonstrated by Ward et al.,’ it is sometimes possible to distinguish RLN paralysis from high vagus nerve paralysis with a videolaryngeal examination. This localization allows the diagnostician to direct his efforts toward either the skull base (in the case of proximal lesions), or the neck and chest (for lesions distal to the nodose ganglion). Consideration of the side of the paralysis is also important because left-sided lesions require careful examination of the mediastinum. We have listed the causes of vocal cord paralysis that were encountered in 84 Stanford patients (Fig. 1). These data are comparable to those found in the literature (Table 2 and Fig. 4). The most common cause of unilateral paralysis according to most reports is neoplasm, especially lung cancer. This is followed closely by surgical trauma, particularly thyroidectomy. Idiopathic paralysis continues to be a common finding. With the knowledge of the common causes of VCP, a logical approach to diagnosis can be made. A thorough history and physical examination, including flexible office endoscopy, are a prerequisite to any diagnostic studies. The nasopharyngoscope not only allows careful, comfortable inspection of the vocal cords, but also enables palpation of the supraglottic larynx, to assess the integrity of the superior laryngeal nerves.
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Volume 107 Number 1 July 1992
Contemporary evaluation of unilateral vocal cord paralysis 89
The most important objective in evaluation of a patient with vocal cord paralysis is exclusion of the existence of a treatable, potentially life-threatening primary cause of the condition. A chest x-ray film remains a useful screening study; however, its limitations must be recognized. Glazer et al.'" demonstrated that of 18 mediastinal masses seen on CT scan, only five were seen on plain film. Advanced imaging studies such as the CT scan and MRI are now available at a moderate cost. The CT scan is a very sensitive study for lesions in the neck and upper chest and is accessible in most communities. The MRI offers improved resolution, especially in the brainstem and skull base, and requires no exposure to ionizing radiation. " Although controversy persists, the current radiologic literature suggests that when MRI is available, it is more suitable for diagnosing pulmonary and mediastinal lesions that are likely to be associated with VCP,'2-'4and it is gaining increasing acceptance in the diagnosis of lesions of the head and neck." There appears to be no need for obtaining such studies as an erythrocyte sedimentation rate, VDRL, glucose level, complete blood count, urinalysis, chemistry profile, or thyroid function studies. The total cost of these simple laboratory tests at Stanford Medical Center in 1990 was $387.76. The diseases revealed by these tests are very rarely responsible for VCP, and usually the diagnosis is already known at the time of development of VCP. When CT or MRI are used, the need for a thyroid scan ($495) and barium swallow ($292) is also obviated. Endoscopy remains a valuable diagnostic tool, both for elimination of the possibility of an occult cancer and for establishment of cricoarytenoid (CA) joint mobility. Alternatively, CA joint fixation can be inferred if electromyography demonstrates action potentials despite lack of vocal cord movement. l 6 Our investigation shows that there is a large amount of variability in the diagnostic practices of otolaryngologists, even those grouped in a relatively small geographic area and from largely similar training backgrounds. It was interesting to note the trend toward use of advanced imaging studies among the younger physicians and also the broader workup in this group. Otolaryngologists should adopt a uniform approach to UVCP. A chest roentgenogram remains a very useful study; it should be followed by MR imaging of the neck if the paralysis occurs on the right side, and MR imaging of the neck down to the arch of the aorta if the paralysis is on the left side. CT scanning remains an excellent alternative. If these tests are unrevealing, endoscopy
(including bronchoscopy, esophagoscopy, and direct laryngoscopy) should be performed. CONCLUSIONS 1. There continues to be much variability among the
diagnostic practices of otolaryngologists who evaluate patients with VCP of unknown origin. Younger physicians tend to expend more resources in the course of their evaluation than physicians with greater experience. 2 The advent of advanced imaging tests (MRI and CT) allows a comprehensive search for occult causes of VCP; these tests are readily obtainable, relatively inexpensive, and produce little morbidity to the patient. 3 A cost-effective, medically sound approach to the patient with UVCP of unknown origin includes a chest roentgenogram followed by an MRI or CT. The areas to be scanned depend on the side of the paralysis: for left UVCP, scan the neck to the aorta; for right UVCP, scan the neck. If these tests are unrevealing, panendoscopy should be performed. 4. There is little yield from ordering screening laboratory tests such as complete blood count, chemistry panel, urinalysis, VDRL, or FTA-ABS, thyroid function tests, or erythrocyte sedimentation rate. These tests should not routinely be ordered. Additionally, when either CT or MRI imaging is used, thyroid scans and barium swallows are unnecessary. We would like to thank Martha K. Terris, MD, for her careful editorial assistance with this manuscript. REFERENCES
I . Parnell FW, Brandenburg JH. Vocal cord paralysis: a review of 100 cases. Laryngoscope 1970;XO: 1036-45. 2. Maisel RH, Ogura JH. Evaluation and treatment of vocal cord paralysis. Laryngoscope 1974;84:302-16. 3. Titche LL. Causes of recurrent laryngeal nerve paralysis. Arch Otolaryngol 1976;102:259-61. 4. Kearsley JH. Vocal cord paralysis-an etiologic review of 100 cases over 20 years. Aust N Z J Med 1981;11:663-6. 5. Barondess JA, Pompei P, Schley WS. A study of vocal cord palsy. Trans Am Clin Climatol Assoc 1985;97:141-8. 6. Willatt DJ, Stell PM. The prognosis and management of idiopathic vocal cord paralysis. Clin Otolaryngol 1989;14:247-50. 7. Ojawa Y, Takashi M , Hiroshi M. Recurrent laryngeal nerve paralysis. In: Sacristan T. Alvarez-Vicent JJ, Bartual J, et al., eds. Otorhinolaryngol Head Neck Surg. Amsterdam: Kugler & Ghedini Publications, I990:202 1-4. 8. Bevan K, Griffiths MV. Morgan MH. Cricothyroid muscle paralysis: its recognition and diagnosis. J Laryngol Otol 1989;103:I9 1-5.
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9. Ward PH, Berci G. Observations on so-called idiopathic vocal cord paralysis. Ann Otol Rhino1 Laryngol 1982;91:558-63. 10. Glazer HS, Aronberg DJ, Lee JKT, Sagel SS. Extralaryngeal causes of vocal cord paralysis: CT evaluation. AJR 1983;141:527-31. 11. Jacobs CJ, Harnsberger HR, Lutkin RB, Osborn AG, Smoker WR, Parkin JL. Vagal neuropathy: evaluation with CT and MR imaging. Radiology 1987;164:97-102, 12. Webb WR, Jensen BG, Sollitto R, et al. Bronchogenic carcinoma: staging with MR compared with staging with CT and surgery. Radiology 1985;156:117-24.
13. Epstein DM, Kressel H, Gefter W, et al. MR imaging of the mediastinum: a retrospective comparison with computed tomography. J Comp Assist Tomogr 1984;8:670-6. 14. Heelan RT, Martini N. Westcott JW, et al. Carcinomatour involvement of the hilum and mediastinum: computed tomographic and magnetic resonance evaluation. Radiology 1985;156:111-5. 15. Lufkin RB, Hanafee W. Magnetic resonance imaging of head and neck tumors. Cancer Metastasis Rev 1988;7: 19-38. 16. Miller RH, Rosenfield DB. The role of electromyography in clinical laryngology. OTOLARYNGOL HEADNECK SURC1984; 92:287-91.
AVAILABLE NOW! The FIVE-YEAR (1986-1990) CUMULATIVE INDEX TO OTOLARYNGOLOGY -HEAD AND NECK SURGERY can be purchased from the Publisher for $44.00. This comprehensive 104-page reference guide is a current presentation of all topics included in the Journal from January 1986 through December 1990 (volumes 94103)-the past 10 volumes. It incorporates complete references to more than 640 original articles, abstracts, case reports, letters, and editorials. It features 1668 Subject Headings, under which there are 3247 references. Each subject entry lists the complete article title, author(s), volume, page(s), and year of publication. In addition, it includes 3190 Author Entries, which list contributors, along with their respective titles, author-to-author referral, volume, page, and publication. To purchase, call or write: Mosby-Year Book, Inc., 11830 Westline Industrial Dr., St. Louis, Missouri 63146-3318, or telephone FREE 1-800-325-4177, extension 4351, Journal Fulfillment (in Missouri, call collect at 3 14-872-8370, extension 435 I , Journal Fulfillment). PREPAYMENT REQUIRED. Make checks payable to Mosby-Year Book, Inc.; (all payments must be in U.S. funds drawn on a U.S. bank). Price: $44.00 in the U.S.; $50.50 in Canada; and $48.50 in other countries (price includes mailing charges).
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310
Otolaryngology Head and Neck Surgery March 1993
News and Announcements
held July 26-30, 1993, at the Tamarron Resort in Durango, Colorado. This 28 hour review and update will encompass all the clinically important areas of MR imaging. Important new concepts and pathological/imaging correlations in the body, musculoskeletal system, ENT, head and neck, brain, and spine will be explored. Daily case presentations will supplement these lectures and will serve to test the registrants' diagnostic abilities in MR imaging. This complete review of MR imaging will be presented by nationally recognized leaders in magnetic resonance imaging. As a result of this comprehensive review, registrants will become familiar with current applications of MR imaging and will be able to integrate many of these applications directly into their practice. Program chairmen for this presentation will be Robert Quencer, MD (University of Miami), Victor Haughton, MD (Medical College of Wisconsin). Twenty-eight credits of Category I will be available. For further information, please contact Marti Carter, CME, Inc., 11011 West Nort Ave., Milwaukee, Wisconsin 53226, or call (414) 771-9520. Ear, Nose, and Throat Diseases: 1993 Update
Children's Hospital of Pittsburgh will hold its 18th Annual Symposium, "Ear, Nose, and Throat Diseases in Children: A 1993 Update." This symposium will be held July 30-31, 1993. CME credits will be awarded.
For further information, please contact the Department of Pediatric Otolaryngology, Children's Hospital of Pittsburgh, 3705 Fifth Avenue at DeSoto St., Pittsburgh, Pennsylvania 15213, or call (412) 692-8577. Twenty-fifth Annual Meeting - Head and Neck Oncologists
The Association of Head and Neck Oncologists of Great Britain will sponsor the Twenty-fifth Annual Meeting of Head and Neck Oncology, to be held in Edinburgh, Scotland, United Kingdom, on August 23-26, 1993. International and local faculty will present extensive social and family programs. For further information, please contact Mr. P. J. Bradley, Honorary Secretary, Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital, Queens Medical Centre, Nottingham, NG7 2UH, England, or phone 0602421421. Sixth International Congress on Interventlonal Ultrasound
The Sixth International Congress on Interventional Ultrasound will be held in Copenhagen, Denmark, on September 7-10, 1993. For further information, please contact Christian Nolsoe, Congress Secretary, Department of Ultrasound, Herlev Hospital, University of Copenhagen, DK-2730 HerlevDenmark, or call + 45/ 44 53 53 00 ext. 3240.
CORRECTION
The Supplement to the December 1992 issue of the JOURNAL (Volume 107, Number 6, Part 2), incorrectly listed Dr. Bruce R. Gordon as Chief of Otolaryngology at the Massachusetts Eye and Ear Institute. Dr. Joseph Nadol is Chief of Otolaryngology at the Massachusetts Eye and Ear Infirmary. Dr. Gordon is Chief of Otolaryngology at Cape Cod Hospital.
