- Email: [email protected]
Laryngoscopy in thyroid surgery—essential standard or unnecessary routine?
Laryngoscopy in thyroid surgery— essential standard or unnecessary routine? Katja Schlosser, MD,a Mike Zeuner, MD,b Maria Wagner, MD,a Emily P. Slater, PhD,a Emilio Domínguez Fernández, MD,a Matthias Rothmund, MD,a and Katja Maschuw, MD,a Marburg and Frankfurt/Main, Germany
Background. Preoperative and postoperative laryngoscopy has been recommended for diagnostic and forensic reasons as a standard procedure in all patients who undergo thyroid surgery. The aim of this study was to find a more selective approach by defining patients at risk of developing vocal fold palsy (VFP). Methods. The history of neck explorations, results of laryngoscopy, and histology were registered in all patients who underwent thyroid surgery at our institution between 1995 and 1999. Patients with pathologic findings at postoperative laryngoscopy underwent reassessment of voice and vocal fold (VF) mobility 6 months later. Results. Unilateral VFP was detected preoperatively in 13 of 695 patients (1.9%). Of the 13 patients, only 1 patient was asymptomatic, had no history of neck surgery, and had no suspected malignancy. Postoperative laryngoscopy revealed a new development of VFP in 68 of 695 patients (9.8%). All patients with a permanent VFP had symptoms immediately after operation. Asymptomatic VFPs always recovered. Conclusions. Preoperative laryngoscopy is justified in symptomatic patients who undergo reoperation or in patients when malignancy is suspected. The necessity of a preoperative laryngoscopy in all other patients must be questioned. Postoperative laryngoscopy and additional diagnostic testing should be reserved for symptomatic patients. (Surgery 2007;142:858-64.) From the Department of Visceral, Thoracic and Vascular Surgery, Philipps-University, Marburg, Germany,a and the Department of Trauma and Orthopedic Surgery, Berufsgenossenschaftliche Unfallklinik, Frankfurt/Main, Germanyb
BACKGROUND Preoperative and postoperative laryngoscopy is considered by many authors to be a standard preoperative assessment in all patients who undergo thyroid surgery.1-3 Preoperative laryngoscopy should confirm normal vocal fold (VF) mobility and detect other pathologies that may be amenable to treatment before thyroidectomy. Postoperative laryngoscopy is recommended mainly for diagnostic and medico-legal reasons. Moreover, postoperative laryngoscopy is advocated to assess the
Accepted for publication September 6, 2007. Reprint requests: K. Schlosser, MD, Department of Visceral, Thoracic and Vascular Surgery, Philipps-University, Marburg, Baldingerstrasse, Marburg, Germany. E-mail: [email protected]. 0039-6060/$ - see front matter © 2007 Mosby, Inc. All rights reserved. doi:10.1016/j.surg.2007.09.008
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rate of recurrent laryngeal nerve (RLN) palsies as one of the main criteria for surgical quality.4 Different endocrine and operative guidelines range widely in their recommendations regarding the importance of the use of preoperative and postoperative laryngoscopy in patients who undergo thyroid surgery. In current American endocrine guidelines, preoperative laryngoscopy is recommended in patients with malignant disease.5 The British Association of Thyroid & Endocrine Surgeons suggest laryngoscopic investigation in patients with vocal changes, with previous neck explorations, or if operation is to be performed in patients with a suspected or proven thyroid malignancy.6 The German Society of Surgeons advocates the routine use of a preoperative and postoperative laryngoscopy in all patients who undergo thyroid surgery.7 Preoperative and postoperative voice changes can be considered to be clinical signs of VF palsy (VFP); however, a unilateral VFP can be detected in asymptomatic patients as well,4 Therefore,
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voice changes cannot serve as the only indication to perform a laryngoscopy. The aim of this retrospective study was to determine whether the routine use of a preoperative and postoperative laryngoscopy in all patients who underwent thyroid surgery is really necessary or whether a more selective approach would be more feasible in patients at risk of developing a VFP. PATIENTS AND METHODS All patients who underwent thyroid surgery at our institution between January 1, 1995 and December 31, 1999 were considered for reevaluation. An otorhinolaryngologist the day before and 2 or 3 days after surgery performed a routine preoperative and postoperative laryngoscopy. Because of medico-legal reasons, the attending surgeon(s) did not perform the laryngoscopy. Findings at laryngoscopy were defined as normal, unilateral vocal fold palsy (VFP), or bilateral VFP. Before operation, history of previous neck explorations, symptoms suggestive of an impairment of VF mobility, such as hoarseness or dyspnea, the results of preoperative laryngoscopy, the suspected pathology of the thyroid disease (benign or malignant), and the results of the routinely performed examination where the surgical indication was verified, were recorded. Operation was performed according to local standards based on the recommendations of the German Society of Surgeons.2 Identification of the RLN was mandatory and was attempted in all patients except for enucleations of ventral nodules in the isthmus of the thyroid. Intraoperative neuromonitoring was not performed on a regular basis. The results of histopathology, the findings during postoperative laryngoscopy, and the incidence of need for tracheostoma after bilateral VFP were registered. Symptomatic patients with a pathologic postoperative laryngoscopy were advised to attend a logopedic examination, which included a complete phoniatric and neuro-laryngeal evaluation and, if necessary, a consecutive speech therapy. Patients with pathologic findings at postoperative laryngoscopy underwent a follow-up examination 6 months after operation, which included an assessment of voice quality and additional laryngoscopy. Patients with an inconspicuous postoperative laryngoscopy were not scheduled for follow-up. A VFP that persisted for more than 6 months after thyroid surgery, which was confirmed by repeated laryngoscopies, was defined as permanent. Postoperative VFP was assumed to be permanent in all patients who died without evidence of recovery of VF mobility before follow-up.
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Data presentation and statistical analysis. Data are presented as mean ⫾ SEM. Categories were analyzed by performing the Fisher exact test. Probable differences between independent categories were assessed by the Mann-Whitney U test. Data analysis was carried out on a computerized basis using the statistic program SPSS, version 10.0.5 (SPSS Corporation, Chicago, Ill). Significance was assumed if P values were less than .05. RESULTS From January 1, 1995 until December 31, 1999, 763 patients underwent thyroid surgery at our institution. Of those patients, 695 were included in the retrospective analysis. Sixty-four patients were excluded because of incomplete data, and 4 patients were excluded because of lack of follow-up. The mean age of the patients was 50 ⫾ 15 years (range, 11-95 years). In all, 197 patients were men and 498 patients were women; the sex ratio was 1:2.5. Preoperative laryngoscopy. Symptomatic versus asymptomatic patients: Of 695 patients, 601 patients (86.5%) were asymptomatic based on clinical signs suggestive for VFP, such as voice changes or dyspnea. Preoperative laryngoscopy revealed unilateral VFP in 5 patients (0.8% of all asymptomatic patients). Of 695 patients, 94 patients (13.5%) complained of symptoms that suggested VFP. Preoperative laryngoscopy confirmed the suspected nerve lesion in only 8 of all symptomatic patients (8.5%). Initial versus reoperative thyroid surgery: Of the 695 patients, 630 patients underwent initial thyroid surgery. Preoperative laryngoscopy revealed a unilateral VFP in 7 patients (1.1%). Of these patients, 65 underwent reoperative thyroid surgery. Preoperative laryngoscopy revealed a unilateral VF palsy in 6 patients (9.2%). The incidence of pathologic findings at preoperative laryngoscopy was greater in patients who underwent reoperative surgery than in those who underwent initial operation (P ⬍ .01). Suspected benign versus suspected malignant thyroid disease: Overall, 516 of the 695 patients underwent operation for a suspected benign disease. Preoperative laryngoscopy revealed a unilateral VFP in 6 patients (1.2%, 3 patients who underwent initial and 3 patients who underwent reoperative surgery). The VFP in the 3 patients who underwent reoperative surgery was acquired during previous neck explorations. The VFP in the 3 patients who underwent initial thyroid surgery for a suspected benign disease resulted most likely from a dysfunction of the recurrent laryngeal nerve because of pressure caused by
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Table I. Data of patients with unilateral VFP detected at preoperative laryngoscopy* Initial TS/ Reop. TS
Preop. symptoms
1 6
Initial Initial
Yes Yes
Proven malignancy Suspected malignancy
TTx TTx
3
Initial
Yes
Suspected malignancy
Hemitx
4 2 5 7 8
Initial Initial Initial Initial Reop
Yes Yes Yes No No
9
Reop
No
10
Reop
Yes
11
Reop
Yes
12
Reop.
No
13
Reop.
No
Suspected malignancy Huge goiter with nodules Huge goiter with nodules Huge goiter with nodules Goiter with nodules ⫹ secondary HPT Thyroid enlarged with nodules ⫹ primary HPT Huge goiter with nodules ⫹ primary HPT Suspected malignancy (medullary TC) Suspected malignancy (medullary TC) Proven malignancy
Indication for surgery
Surgery
Histology
Postoperative laryngoscopy Identical Identical
Hemitx Hemitx Hemitx Bilat. subtotal Tx Residual Hemitx
Papillary TC Squamous cell carcinoma Hürthle cell neoplasm Benign nodules Benign nodules Benign nodules Benign nodules Benign nodules
Residual TTx
Benign nodules
Identical
Residual Hemitx
Benign nodules
Identical
Residual TTx
Medullary TC
Residual TTx
C-cell hyperplasia
Patient refused reexamination Identical
Residual TTx
Anaplastic TC
Identical
Identical Normal Identical Identical Identical Identical
TS, thyroid surgery; reop., reoperation; preop., preoperative; TTx, total thyroidectomy; hemitx, hemithyroidectomy; Tx, thyroidectomy; bilat., bilateral; TC, thyroid cancer; HPT, hyperparathyroidism; identical, no additional pathology detectable when compared with preoperative laryngoscopy. *Preoperative and postoperative symptoms and results of laryngoscopy in 13 of the 695 patients with unilateral vocal fold palsy detected at preoperative laryngoscopy.
the enlarged thyroid glands. These 3 patients underwent thyroidectomy for huge goiters. The weight of the resected specimen was 140 g and 120 g, respectively, in the 2 patients who underwent hemithyroidectomy and 250 g in the patient who underwent a bilateral subtotal thyroidectomy. The results are displayed in Table I. Malignancy was suspected or proven in 179 of the 695 patients. Preoperative laryngoscopy revealed a unilateral VFP in 7 patients (3.9%). Thus, the incidence of pathologic findings at preoperative laryngoscopy was greater in patients with a suspected or proven thyroid malignancy than in those with a suspected benign disease (P ⬍ .02). Summation of the results of preoperative laryngoscopy: Preoperative laryngoscopy revealed a unilateral VFP in 13 of the 695 patients (1.9%). Of these patients, 12 underwent either reoperative surgery, had symptoms suggestive for a VFP, or underwent thyroidectomy for a suspected or already proven thyroid malignancy. Preoperative laryngoscopy detected a VFP in only 1 of the 420 patients (0.2%) with no symptoms that suggested of VFP, no former neck explorations, and no suspected or proven thyroid malignancy. The preoperative knowledge of a VFP facilitated dissection on the affected side and led to an extremely careful
dissection on the side of the nonparalyzed vocal fold. No additional palsy was detectable at postoperative laryngoscopy in these patients. The detection of a preoperative unilateral VFP altered neither the indication for operation nor the extent of surgical resection. Data from these 13 patients are displayed in Table I. Postoperative laryngoscopy. Results of postoperative laryngoscopy are displayed in Table II. Sixty-eight patients (9.8%) developed a new onset VFP. Of these 68 patients, 13 were asymptomatic, whereas 55 complained about symptoms that suggested a VFP immediately after operation. None of the 13 asymptomatic patients underwent logopedic counseling; 24 of the 55 symptomatic patients underwent logopedic examination with a phoniatric and neuro-larnygeal examination and subsequent speech therapy, which resulted in a recovery of voice and VF mobility in 17 of them. None of our patients required vocal fold medialization by injection or thyroplasty. Five patients died within 6 months of operation and before follow-up. One patient died during the hospital stay as a result of mediastinitis and consecutive sepsis, 3 patients died from progression of malignant disease, and 1 patient died from cardiac insufficiency; the latter patient who suffered from
0/25 0/25 n.r. 0 VFM, vocal fold motion; postop., postoperative; n.r., not recorded; d, patients died before follow-up with persistent bilateral RLN palsy. *Preoperative and postoperative symptoms and results of laryngoscopy in 630 of the 695 patients who underwent initial thyroid surgery. †No additional pathology detectable when compared with preoperative laryngoscopy.
1/1 1/1 0/1 0 1/10 5/10 0/10 0 13/39 36/39 7/39 [2d/7] 6† 57/544 n.r. n.r. 1
0/4 4/4 3/4 [2d/3] 0
623 25 1 10
bilateral palsy required tracheotomy within the postoperative setting. VFP was considered permanent in these patients. Postoperative new development of VFP was permanent in 12 of the 695 patients (1.8%). All patients had obvious symptoms that suggested VFP immediately after operation. Postoperative new onset of VFP was transient in 56 of the 695 patients (8.1%). Follow-up revealed a transient VFP in all asymptomatic patients. The correlation between postoperative voice changes and permanent VF palsies proved to be significant (P ⬍ .001). Initial versus reoperative thyroid surgery: VFP was permanent in 10 of the 630 patients who underwent initial thyroid surgery (1.6%), whereas VF mobility recovered in 44 of the 630 patients (7.0%) (Table III). VFP was permanent in 2 of the 65 patients who underwent reoperative thyroid surgery (3.1%), whereas VF mobility recovered in 12 of the 65 patients (18.5%) (Table IV). The postoperative rate of transient as well as permanent VFPs was greater in patients who underwent reoperative surgery (P ⬍ .01). Benign versus malignant histopathology: Histopathology revealed benign disease in 644 of the 695 patients. Postoperative laryngoscopy demonstrated a new onset of VFP in 57 of the 644 patients (8.9%), which was permanent in 8 patients (1.2%). Malignancy was verified by histology in 51 of the 695 patients. Postoperative laryngoscopy demonstrated new onset VFP in 11 of the 51 of these patients (21.6%), which was permanent in 4 of them (7.8%). The incidence of pathologic findings at postoperative laryngoscopy, as well as the incidence of permanent VFPs, was greater in patients with malignant disorders than in those with benign disorders (P ⬍ .01).
Table III. Preoperative and postoperative laryngoscopy in patients who underwent initial thyroid surgery*
VFM, vocal fold motion.
4
86.2%
39
589
544
7.0% 1.6% 0.9% 0.4% 3.7%
Preoperative normal laryngoscopy (n ⫽ 623) Preoperative symptoms Postoperative symptoms Permanent VFP at follow-up Preoperative laryngoscopy pathologic (n ⫽ 7)
48 11 6 3 25
Postop. laryngoscopy Postop. laryngoscopy unilateral decreased bilateral decreased No postop. VFM VFM laryngoscopy
Percentage
Postop. normal Postop. laryngoscopy Postop. laryngoscopy laryngoscopy unilateral VFP bilateral VFP
Unilateral VFP Reduced unilateral VFM Bilateral VFP Bilateral reduced VFM Refusing examination because of no symptoms suggestive for VFP Normal
Number of patients
Summary
Table II. Results of postoperative laryngoscopy in patients with a normal examination before operation
10 permanent VFP 7
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2 permanent VFP 7 1 0/2 0/2 0/2 0 postop., postoperative; n.r., not recorded; d, patients died before follow-up with persistent bilateral RLN palsy. *Preoperative and postoperative symptoms and results of laryngoscopy in 65 patients who underwent reoperation. †No additional pathology detectable when compared with preoperative laryngoscopy.
0/1 0/1 0/1 0 4/9 9/9 1/9 5† 14/45 n.r. n.r.
1/2 2/2 1d/2 0
9 45
2
1
2
0
59
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Preoperative normal laryngoscopy (n ⫽ 59) Preoperative symptoms Postoperative symptoms Permanent VFP at follow up Preoperative laryngoscopy pathologic (n ⫽ 6)
Postop. laryngoscopy bilateral decreased VFM Postop. laryngoscopy unilateral decreased VFM Postop. laryngoscopy bilateral VFP Postop. laryngoscopy unilateral VFP Postop. normal laryngoscopy
Table IV. Preoperative and postoperative laryngoscopy in patients who underwent reoperative thyroid surgery*
No postop. laryngoscopy
Summary
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DISCUSSION The preoperative knowledge of a VFP enables appropriate counseling, which can outline a plan for the extent of operation and, furthermore, will facilitate dissection on the affected side and will enhance careful dissection on the opposite side.1,4,8,9 Especially in patients with a suspected or proven thyroid malignancy, the preoperative detection of a VFP will lead to additional diagnostic testing to evaluate an infiltration of adjacent structures. The results of the current study demonstrate that a preoperative laryngoscopy is justified in all patients who undergo reoperative surgery, those who have a suspected or proven malignant disease, as well as those who have symptoms that suggest a VFP. The routine use of preoperative laryngoscopy in all other patients seems to be of limited value. Of our 695 patients, 420 patients had no symptoms that suggested a VFP, no former neck explorations, and no suspected or proven malignancy. Preoperative laryngoscopy detected a VFP in only 1 patient (0.2%). If we had been unaware of the preoperative VFP in this patient, we would have performed a careful dissection on either side as usual and thus would have preserved the nonparalyzed RLN in all likelihood. These results suggest that a more selected approach to the use of preoperative laryngoscopy is feasible and acceptable. Patients who lack symptoms that suggest VFP, no former neck explorations, and no suspected or proven malignancy should not undergo routine preoperative laryngoscopy. Postoperative laryngoscopy was normal in 627 patients (90.2%). Unfortunately, we do not know how many of these patients had voice changes because only patients with a pathologic postoperative laryngoscopy underwent voice assessment and repeated laryngoscopy thereafter. Although an injury to the RLN is considered to be the main cause of voice change or breathing difficulties after thyroid surgery,10,11 these symptoms may also result from damage to the external branch of the superior laryngeal nerve (EBSLN)12,13 or not be related to the impaired RLN function at all.14-22 Indirect laryngoscopy often fails to detect other larynx pathologies except for VFPs, and an extensive logopedic and phoniatric evaluation is advocated. With respect to the findings of Musholt et al1 and Lombardi et al,24 we agree that voice changes and postoperative VF mobility must be considered as 2 separate entities. Additional investigation is mandatory, especially when postoperative indirect laryngoscopy is normal in symptomatic patients.1,3,23
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Unfortunately, a reliable assessment of voice changes after thyroid surgery is lacking.1,23,24 Netto et al23 suggested the use of routine videolaryngoscopy, voice analysis, and a vocal self-assessment questionnaire. This approach must be validated in the future. In the current study, of 55 symptomatic patients with a postoperative VFP, only 24 patients underwent logopedic examination and speech therapy. Moreover, none of the asymptomatic patients underwent logopedic examination and speech therapy immediately after surgery, and follow-up revealed recovery of voice and VF mobility in all patients. Asymptomatic patients do not require additional therapy. Most voice alterations that occur after thyroid and parathyroid surgery are self-limiting and of short duration.15-18 Whenever the laryngeal nerve and especially the RLN is visualized and is preserved intact on the affected side, which is preferably confirmed by intraoperative neuromonitoring, the patient should be reassured that a transient VFP is the most likely explanation, and that an increased likelihood of recovery exists. In patients with minor symptoms, laryngoscopy can even be deferred for some weeks or months and be performed if symptoms persist. In patients with major postoperative symptoms that suggest a VFP, such as severe hoarseness, dyspnea, or aspiration, postoperative laryngoscopy should be the first examination to identify individuals who need phoniatric or surgical therapy. In contrast, the patient’s desire to improve voice quality and thus improve his or her voice-related quality of life should be an indication for additional examination, with a consecutive conservative (speech therapy) or surgical therapy (medialization of a vocal fold) when VFP proves to be permanent.25,26 The routine use of postoperative laryngoscopy in all patients regardless of symptoms must be scrutinized. Routine postoperative laryngoscopy is often justified because of medico-legal concerns.1 In our opinion, obtaining informed consent of a patient who undergoes thyroid surgery, describing the dissection of the RLN in detail and (if available) the results of intraoperative neuromonitoring on either side within the operation record, and initiating a phoniatric examination in symptomatic patients is essential and will help to protect the surgeon from subsequent litigation. CONCLUSIONS First, although simple and quick, routine laryngoscopy seems to be inadequate as an instrument for
quality control by means of documenting the intact laryngeal function thoroughly. An objective, evidencebased approach to assess postoperative voice changes has yet to be validated on a wide population. Second, the incidence of VFPs in asymptomatic patients with a suspected benign disease and no previous neck surgery was extremely low and did not alter the extent of operation. Routine preoperative laryngoscopy in this subgroup of patients seems to be of limited value. Third, postoperative VFP was transient in all asymptomatic patients, and no patients underwent phoniatric/logopedic therapy. Because it is impossible to improve on the well-being of an asymptomatic patient, one may question the necessity of performing routine laryngoscopy in patients with no obvious or perceptible symptoms. Fourth, we should pay closer attention to complaints of voice changes, especially when these symptoms do not translate into objective findings at postoperative laryngoscopy. EBSLN palsy must be excluded, and thus, additional assessment is warranted. REFERENCES 1. Musholt TJ, Musholt PB, Garm J, Napiontek U, Keilmann A. Changes of the speaking and singing voice after thyroid or parathyroid surgery. Surgery 2006;140:978-88. 2. AWMF-Leitlinien-Register Nr.003/002. Guideline for the therapy of benign thyroid diseases; Grundlagen der Chirurgie G 80, Beilage zu: Mitteilungen der Dt. Ges. f. Chirurgie, 27. Jg., Nr. 3, Stuttgart, July 1998. 3. Steurer M, Passler C, Denk DM, Schneider B, Niederle B, Bigenzahn W. Advantages of recurrent laryngeal nerve identification in thyroidectomy and parathyroidectomy and the importance of preoperative and postoperative laryngoscopic examination in more than 1000 nerves at risk. Laryngoscope 2002;112:124-33. 4. Farrag TY, Samlan RA, Lin FR, Tufano RP. The utility of evaluating true vocal fold motion before thyroid surgery. Laryngoscope 2006;116:235-8. 5. AACE/AME Taskforce on Thyroid Nodules. American Association of Clinical Endocrinologists and Associazione Medici Endocrinologi medical guidelines for clinical practice for the diagnosis and management of thyroid nodules. Endocr Pract 2006;12:63-102. 6. British Association of Thyroid & Endocrine Surgeons. Surgical treatment of diseases of the thyroid gland. Available from: http://www.baes.info. 7. German Society of Surgery. [Guideline for the therapy of benign thyroid diseases]. Mitteilung der Deutschen Gesellschaft für Chirurgie 1998;27:G80. 8. Randolph GW, Kamani D. The importance of preoperative laryngoscopy in patients undergoing thyroidectomy: voice, vocal cord function, and the preoperative detection of invasive thyroid malignancy. Surgery 2006;139:357-62. 9. Erbil Y, Barbaros U, Issever H, Borucu I, Salmaslıog˘lu A, Mete Ö, et al. Predictive factors for recurrent laryngeal nerve palsy and hypoparathyroidism after thyroid surgery. Clin Otolaryngol 2007;32:32-7. 10. Dralle H, Kruse E, Hamelmann WH, Grond S, Neumann HJ, Sekulla C, et al. [Not all vocal cord failure following
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11.
12.
13. 14.
15.
16.
17.
18.
thyroid surgery is recurrent paresis due to damage during operation. Statement of the German Interdisciplinary Study Group on Intraoperative Neuromonitoring of Thyroid Surgery concerning recurring paresis due to intubation]. Chirurg 2004;75:810-22. Sinagra DL, Montesinos MR, Tacchi VA, Moreno JC, Falco JE, Mezzadri NA, et al. Voice changes after thyroidectomy without recurrent laryngeal nerve injury. J Am Coll Surg 2004;199:556-60. Cernea CR, Ferraz AR, Furlani J, Monteiro S, Nishio S, Hojaij FC, et al. Identification of the external branch of the superior laryngeal nerve during thyroidectomy. Am J Surg 1992;164:634-9. Teitelbaum BJ, Wenig BL. Superior laryngeal nerve injury from thyroid surgery. Head Neck 1995;17:36-40. Yeung P, Erskine C, Mathews P, Crowe PJ. Voice changes and thyroid surgery: is pre-operative indirect laryngoscopy necessary? Aust N Z J Surg 1999;69:632-4. Hong KH, Kim YK. Phonatory characteristics of patients undergoing thyroidectomy without laryngeal nerve injury. Otolaryngol Head Neck Surg 1997;117:399-404. Debruyne F, Ostyn F, Delaere P, Wellens W. Acoustic analysis of the speaking voice after thyroidectomy. J Voice 1997; 11:479-82. McIvor NP, Flint DJ, Gillibrand J, Morton RP. Thyroid surgery and voice-related outcomes. Aust N Z J Surg 2000; 70:179-83. Stojadinovic A, Shaha AR, Orlikoff RF, Nissan A, Kornak MF, Singh B, et al. Prospective functional voice assessment
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19.
20.
21.
22.
23.
24.
25. 26.
in patients undergoing thyroid surgery. Ann Surg 2002; 236:823-32. Jansson S, Tisell LE, Hagne I, Sanner E, Stenborg R, Svensson P. Partial superior laryngeal nerve (SLN) lesions before and after thyroid surgery. World J Surg 1988;12:522-7. Prim MP, de Diego JI, Hardisson D, Madero R, Gavilan J. Factors related to nerve injury and hypocalcemia in thyroid gland surgery. Otolaryngol Head Neck Surg 2001;124:111-4. Pereira JA, Girvent M, Sancho JJ, Parada C, Sitges-Serra A. Prevalence of long-term upper aerodigestive symptoms after uncomplicated bilateral thyroidectomy. Surgery 2003;133: 318-22. Kark AE, Kissin MW, Auerbach R, Meikle M. Voice changes after thyroidectomy: role of the external laryngeal nerve. Br Med J (Clin Res Ed) 1984;289:1412-5. de Pedro Netto I, Fae A, Vartanian JG, Barros AP, Correia LM, Toledo RN, et al. Voice and vocal self-assessment after thyroidectomy. Head Neck 2006;28:1106-14. Lombardi CP, Raffaelli M, D’alatri L, Marchese MR, Rigante M, Paludetti G, et al. Voice and swallowing changes after thyroidectomy in patients without inferior laryngeal nerve injuries. Surgery 2006;140:1026-32. Schulte KM, Roher HD. [Medico-legal aspects of thyroid surgery]. Chirurg 1999;70:1131-8. Hartl DM, Travagli JP, Leboulleux S, Baudin E, Brasnu DF, Schlumberger M. Clinical review: current concepts in the management of unilateral recurrent laryngeal nerve paralysis after thyroid surgery. J Clin Endocrinol Metab 2005 May;90(5):3084-8.
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DISCUSSION Dr Keith S. Heller (Lake Success, New York): I would like to congratulate you for finally providing real data on which to make recommendations. Because for so long we have been hearing absolutes that “you must” and “you should” and “you should never,” which was never based on data. So it is a wonderful study. A question: In the group that did have, not the asymptomatic group post op because clearly if you hadn’t looked you wouldn’t have known and nobody would be the wiser, but in the group who were symptomatic, and particularly in the group with permanent vocal paralysis post op, can you correlate that with surgical findings? Did you know at the time of surgery that this nerve was in jeopardy? And can you then sort out the cases in which postoperative laryngoscopy really came as a surprise to you? But thank you for this great study. Dr K. Schlosser (Marburg, Germany): It was in approximately 50 to 60% of cases that we suspected a vocal fold palsy. As you could see, we did surgery on a large population who also underwent surgery for a malignant thyroid. And in some of these cases, I don’t know the exact number, the recurrent laryngeal nerve had to be resected because of invasion. So in these cases, it was already clear that they will have symptoms and that they will have to undergo logopedic therapy. In cases where intraoperative neuromonitoring was performed and we achieved no signal, well, we suspected nerve damage. However, we usually visualize the nerve in its whole entity, so we never cut it by just not seeing it. Dr John S. Kukora (Abington, Pennsylvania): I very much appreciate the effort and diligence with which you did this study. I have for most of my career since I have been in the Philadelphia area used preoperative laryngoscopy to document the lay of the land before I have operated. I would say that I have found it useful because a lot of people come with symptoms that are in fact referrable to atrophy of their vocal cords from age, from gastroesophageal reflux that creates voice changes. And knowing that the cords move, I can direct these people sometimes to otolaryngologists rather than feeling obligated to take out perhaps a small and clearly benign thyroid nodule for which they are referred. So I think there is some value in the assessment of some patients’ symptoms irrespective of just the issue of the thyroid surgery. On the other hand, I have only found one asymptomatic patient in 20 years who had a paralyzed vocal cord. Given the fact that this man was an attorney who had a papillary thyroid cancer, I really
Schlosser et al 864.e1
did appreciate finding it, because I knew that in my environment I would have had a friendly comment from an attorney that I probably caused that at the time of surgery. I would say that there is an easy way to do this, and it is using a flexible laryngoscope and instead of putting it through the nose just have the patient hold their tongue and slide it over the back of the tongue and have them say “E” and “A” a couple of times. And you can do this as quick as you can listen to their heart sounds. But again I don’t know that it is necessarily cost effective if this is going to have a charge associated with it. And I think depending on your landscape you may or may not want to do this. But I do appreciate your comments. I would ask you, though, what is your definition of symptomatic either pre op or post op by which you decided to apply this technology? Dr K. Schlosser (Marburg, Germany): What we really miss is a manual to assess what a symptomatic patient is. And in the last meeting of this AAES, Dr. Musholt was here and presented a great work concerning exactly this point. And I think we should ask the patients to make a vocal self assessment test and also try to find out if they have hoarseness, even though they say they are asymptomatic. We also have to conduct a manual how to define an asymptomatic patient. In this study, we conducted the patient to be symptomatic when he says “My voice changed” or if hoarseness was obvious or if the patient claims that he developed dyspnea within the last month, or such things. But it was not on a regular manual. Dr Samuel K. Snyder (Temple, Texas): Thank you for presenting this very large and important study. I am interested in that, also, in trying to evaluate this from a nerve monitoring point of view. I heard you indicate that you used it in some of the patients. And that was one of my questions, how often did you use nerve monitoring? Did you find that useful not only in predicting which nerves were injured but, on the flip side, which nerves are normal? Because from my experience in hundreds of these patients, if the nerve monitor is completely normal, those are the ones that have the normal post op laryngoscopy. And that is another measure, I think, that we can use to maybe avoid having to do postoperative laryngoscopy. Dr K. Schlosser (Marburg, Germany): As you can see, the study data is a little older. We are currently actualizing our database. But it goes up to December 1999. And by that time, between 1995 and 1999, we didn’t perform regular intraoperative
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nerve monitoring. Now we do. Since 2001, we do it in every patient. And our results are as you said. Dr William B. Inabnet, III (New York, New York): Given Dr Kukora’s comments, maybe we should add one of the indications to laryngoscopy is being an attorney. Maybe that should be on the list of indications. A couple of questions. Could you please clarify how you define asymptomatic? Because up to 30 or 40% of patients will have some sort of voice change, they may not have hoarseness but they may have a change in pitch, et cetera. Secondly, it looks like you did six month laryngoscopy in all of these patients. Did you see evidence of external branch laryngeal nerve injury? And what you see on laryngoscopy is a tilt towards the contralateral side of the nerve that was injured. And it is very difficult to diagnose in laryngoscopy. But were you able to appreciate that on your six month study? Dr K. Schlosser (Marburg, Germany): I totally agree with you that simple laryngoscopy, and by that time it was indirect laryngoscopy in all of these patients, is not the tool for quality control to be chosen. In patients complaining about voice changes you have to perform a flexible laryngoscopy and in a patient who has a normal result within this study, but symptoms you need to perform a distinct further logopedic examination for this. And you can’t perform this as a surgeon. It is not our field, especially when not the surgeon who had performed the surgery. Well, you would say laryngoscopy was normal and that is it, it will normalize. Well, it will in most of the cases. But there are patients who will have an external branch of the superior laryngeal nerve injury and you might miss this by laryngoscopy. And if the patient is symptomatic, that means decrease in pitch and all the other signs that makes a patient symptomatic, this will not be found by a simple laryngoscopy, right? Then you have to go and and send the patient to an otolaryngologist. Dr Thierry Defechereux (Liege, Belgium): Maybe I missed that point in your presentation. But did you mention in your data the number of patients who had a symptomatic voice after we do surgery and then proceed identifying new preoperative exams? Did you detect nerve palsies after previous surgery in an asymptomatic patient? This might influence your redo-surgery, of course. And I would like to know if you got this data.
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Dr K. Schlosser (Marburg, Germany): You mean within preoperative laryngoscopy? Right. There were 13 patients who had a vocal cord palsy prior to surgery and six of them who had a previous surgery ahead of this. And out of these six patients, there were three symptomatic and another three that were asymptomatic. But that was mainly because these three patients had underwent logopedic therapy after their initial surgery where they developed their vocal cord palsy. Dr Jeffrey A. Van Lier Ribbink (Scottsdale, Arizona): Clearly the more compulsive, I think, we are at looking for voice changes after thyroid and parathyroid surgery, and clearly the more sophisticated techniques we look at that, we are finding that a higher incidence of patients do have voice changes. When I read the literature, almost every study I read states that whatever group is looking at their experience has a less than 1% risk of hoarseness. Should we even accept this anymore in these studies? It seems like perhaps their only method of determining their less than 1% chance of hoarseness is talking to the patient and seeing how they sound. Dr K. Schlosser (Marburg, Germany): On one hand, true. On the other, no. First I want to say that I don’t appreciate if the surgeon who did perform the surgery performs the laryngoscopy examination. Because I don’t know if everybody can free oneself for the opinion and look inside and you might see a slight movement and then claim “well, this is not a complete vocal cord palsy”. If you want to do such an examination as a quality tool, then it has to be done by somebody independent of this surgery group first. Second, if there is a patient who is asymptomatic, that means with really no hoarseness, really no dyspnea, what can you do? You cannot make an asymptomatic patient better. So I think there is no need to further examine these patients. Dr Collin J. Weber (Atlanta, Georgia): I agree wholeheartedly with what Dr Schlosser just said. My take on this in my personal practice is I do not do the laryngoscopy myself because I think it is self serving. I work very closely with two or three of our ENT folks who do this for me on a day’s notice. It is an independent evaluation. I know a lot of you may disagree with that, but that is how I do it.
Background. Preoperative and postoperative laryngoscopy has been recommended for diagnostic and forensic reasons as a standard procedure in all patients who undergo thyroid surgery. The aim of this study was to find a more selective approach by defining patients at risk of developing vocal fold palsy (VFP). Methods. The history of neck explorations, results of laryngoscopy, and histology were registered in all patients who underwent thyroid surgery at our institution between 1995 and 1999. Patients with pathologic findings at postoperative laryngoscopy underwent reassessment of voice and vocal fold (VF) mobility 6 months later. Results. Unilateral VFP was detected preoperatively in 13 of 695 patients (1.9%). Of the 13 patients, only 1 patient was asymptomatic, had no history of neck surgery, and had no suspected malignancy. Postoperative laryngoscopy revealed a new development of VFP in 68 of 695 patients (9.8%). All patients with a permanent VFP had symptoms immediately after operation. Asymptomatic VFPs always recovered. Conclusions. Preoperative laryngoscopy is justified in symptomatic patients who undergo reoperation or in patients when malignancy is suspected. The necessity of a preoperative laryngoscopy in all other patients must be questioned. Postoperative laryngoscopy and additional diagnostic testing should be reserved for symptomatic patients. (Surgery 2007;142:858-64.) From the Department of Visceral, Thoracic and Vascular Surgery, Philipps-University, Marburg, Germany,a and the Department of Trauma and Orthopedic Surgery, Berufsgenossenschaftliche Unfallklinik, Frankfurt/Main, Germanyb
BACKGROUND Preoperative and postoperative laryngoscopy is considered by many authors to be a standard preoperative assessment in all patients who undergo thyroid surgery.1-3 Preoperative laryngoscopy should confirm normal vocal fold (VF) mobility and detect other pathologies that may be amenable to treatment before thyroidectomy. Postoperative laryngoscopy is recommended mainly for diagnostic and medico-legal reasons. Moreover, postoperative laryngoscopy is advocated to assess the
Accepted for publication September 6, 2007. Reprint requests: K. Schlosser, MD, Department of Visceral, Thoracic and Vascular Surgery, Philipps-University, Marburg, Baldingerstrasse, Marburg, Germany. E-mail: [email protected]. 0039-6060/$ - see front matter © 2007 Mosby, Inc. All rights reserved. doi:10.1016/j.surg.2007.09.008
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rate of recurrent laryngeal nerve (RLN) palsies as one of the main criteria for surgical quality.4 Different endocrine and operative guidelines range widely in their recommendations regarding the importance of the use of preoperative and postoperative laryngoscopy in patients who undergo thyroid surgery. In current American endocrine guidelines, preoperative laryngoscopy is recommended in patients with malignant disease.5 The British Association of Thyroid & Endocrine Surgeons suggest laryngoscopic investigation in patients with vocal changes, with previous neck explorations, or if operation is to be performed in patients with a suspected or proven thyroid malignancy.6 The German Society of Surgeons advocates the routine use of a preoperative and postoperative laryngoscopy in all patients who undergo thyroid surgery.7 Preoperative and postoperative voice changes can be considered to be clinical signs of VF palsy (VFP); however, a unilateral VFP can be detected in asymptomatic patients as well,4 Therefore,
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voice changes cannot serve as the only indication to perform a laryngoscopy. The aim of this retrospective study was to determine whether the routine use of a preoperative and postoperative laryngoscopy in all patients who underwent thyroid surgery is really necessary or whether a more selective approach would be more feasible in patients at risk of developing a VFP. PATIENTS AND METHODS All patients who underwent thyroid surgery at our institution between January 1, 1995 and December 31, 1999 were considered for reevaluation. An otorhinolaryngologist the day before and 2 or 3 days after surgery performed a routine preoperative and postoperative laryngoscopy. Because of medico-legal reasons, the attending surgeon(s) did not perform the laryngoscopy. Findings at laryngoscopy were defined as normal, unilateral vocal fold palsy (VFP), or bilateral VFP. Before operation, history of previous neck explorations, symptoms suggestive of an impairment of VF mobility, such as hoarseness or dyspnea, the results of preoperative laryngoscopy, the suspected pathology of the thyroid disease (benign or malignant), and the results of the routinely performed examination where the surgical indication was verified, were recorded. Operation was performed according to local standards based on the recommendations of the German Society of Surgeons.2 Identification of the RLN was mandatory and was attempted in all patients except for enucleations of ventral nodules in the isthmus of the thyroid. Intraoperative neuromonitoring was not performed on a regular basis. The results of histopathology, the findings during postoperative laryngoscopy, and the incidence of need for tracheostoma after bilateral VFP were registered. Symptomatic patients with a pathologic postoperative laryngoscopy were advised to attend a logopedic examination, which included a complete phoniatric and neuro-laryngeal evaluation and, if necessary, a consecutive speech therapy. Patients with pathologic findings at postoperative laryngoscopy underwent a follow-up examination 6 months after operation, which included an assessment of voice quality and additional laryngoscopy. Patients with an inconspicuous postoperative laryngoscopy were not scheduled for follow-up. A VFP that persisted for more than 6 months after thyroid surgery, which was confirmed by repeated laryngoscopies, was defined as permanent. Postoperative VFP was assumed to be permanent in all patients who died without evidence of recovery of VF mobility before follow-up.
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Data presentation and statistical analysis. Data are presented as mean ⫾ SEM. Categories were analyzed by performing the Fisher exact test. Probable differences between independent categories were assessed by the Mann-Whitney U test. Data analysis was carried out on a computerized basis using the statistic program SPSS, version 10.0.5 (SPSS Corporation, Chicago, Ill). Significance was assumed if P values were less than .05. RESULTS From January 1, 1995 until December 31, 1999, 763 patients underwent thyroid surgery at our institution. Of those patients, 695 were included in the retrospective analysis. Sixty-four patients were excluded because of incomplete data, and 4 patients were excluded because of lack of follow-up. The mean age of the patients was 50 ⫾ 15 years (range, 11-95 years). In all, 197 patients were men and 498 patients were women; the sex ratio was 1:2.5. Preoperative laryngoscopy. Symptomatic versus asymptomatic patients: Of 695 patients, 601 patients (86.5%) were asymptomatic based on clinical signs suggestive for VFP, such as voice changes or dyspnea. Preoperative laryngoscopy revealed unilateral VFP in 5 patients (0.8% of all asymptomatic patients). Of 695 patients, 94 patients (13.5%) complained of symptoms that suggested VFP. Preoperative laryngoscopy confirmed the suspected nerve lesion in only 8 of all symptomatic patients (8.5%). Initial versus reoperative thyroid surgery: Of the 695 patients, 630 patients underwent initial thyroid surgery. Preoperative laryngoscopy revealed a unilateral VFP in 7 patients (1.1%). Of these patients, 65 underwent reoperative thyroid surgery. Preoperative laryngoscopy revealed a unilateral VF palsy in 6 patients (9.2%). The incidence of pathologic findings at preoperative laryngoscopy was greater in patients who underwent reoperative surgery than in those who underwent initial operation (P ⬍ .01). Suspected benign versus suspected malignant thyroid disease: Overall, 516 of the 695 patients underwent operation for a suspected benign disease. Preoperative laryngoscopy revealed a unilateral VFP in 6 patients (1.2%, 3 patients who underwent initial and 3 patients who underwent reoperative surgery). The VFP in the 3 patients who underwent reoperative surgery was acquired during previous neck explorations. The VFP in the 3 patients who underwent initial thyroid surgery for a suspected benign disease resulted most likely from a dysfunction of the recurrent laryngeal nerve because of pressure caused by
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Table I. Data of patients with unilateral VFP detected at preoperative laryngoscopy* Initial TS/ Reop. TS
Preop. symptoms
1 6
Initial Initial
Yes Yes
Proven malignancy Suspected malignancy
TTx TTx
3
Initial
Yes
Suspected malignancy
Hemitx
4 2 5 7 8
Initial Initial Initial Initial Reop
Yes Yes Yes No No
9
Reop
No
10
Reop
Yes
11
Reop
Yes
12
Reop.
No
13
Reop.
No
Suspected malignancy Huge goiter with nodules Huge goiter with nodules Huge goiter with nodules Goiter with nodules ⫹ secondary HPT Thyroid enlarged with nodules ⫹ primary HPT Huge goiter with nodules ⫹ primary HPT Suspected malignancy (medullary TC) Suspected malignancy (medullary TC) Proven malignancy
Indication for surgery
Surgery
Histology
Postoperative laryngoscopy Identical Identical
Hemitx Hemitx Hemitx Bilat. subtotal Tx Residual Hemitx
Papillary TC Squamous cell carcinoma Hürthle cell neoplasm Benign nodules Benign nodules Benign nodules Benign nodules Benign nodules
Residual TTx
Benign nodules
Identical
Residual Hemitx
Benign nodules
Identical
Residual TTx
Medullary TC
Residual TTx
C-cell hyperplasia
Patient refused reexamination Identical
Residual TTx
Anaplastic TC
Identical
Identical Normal Identical Identical Identical Identical
TS, thyroid surgery; reop., reoperation; preop., preoperative; TTx, total thyroidectomy; hemitx, hemithyroidectomy; Tx, thyroidectomy; bilat., bilateral; TC, thyroid cancer; HPT, hyperparathyroidism; identical, no additional pathology detectable when compared with preoperative laryngoscopy. *Preoperative and postoperative symptoms and results of laryngoscopy in 13 of the 695 patients with unilateral vocal fold palsy detected at preoperative laryngoscopy.
the enlarged thyroid glands. These 3 patients underwent thyroidectomy for huge goiters. The weight of the resected specimen was 140 g and 120 g, respectively, in the 2 patients who underwent hemithyroidectomy and 250 g in the patient who underwent a bilateral subtotal thyroidectomy. The results are displayed in Table I. Malignancy was suspected or proven in 179 of the 695 patients. Preoperative laryngoscopy revealed a unilateral VFP in 7 patients (3.9%). Thus, the incidence of pathologic findings at preoperative laryngoscopy was greater in patients with a suspected or proven thyroid malignancy than in those with a suspected benign disease (P ⬍ .02). Summation of the results of preoperative laryngoscopy: Preoperative laryngoscopy revealed a unilateral VFP in 13 of the 695 patients (1.9%). Of these patients, 12 underwent either reoperative surgery, had symptoms suggestive for a VFP, or underwent thyroidectomy for a suspected or already proven thyroid malignancy. Preoperative laryngoscopy detected a VFP in only 1 of the 420 patients (0.2%) with no symptoms that suggested of VFP, no former neck explorations, and no suspected or proven thyroid malignancy. The preoperative knowledge of a VFP facilitated dissection on the affected side and led to an extremely careful
dissection on the side of the nonparalyzed vocal fold. No additional palsy was detectable at postoperative laryngoscopy in these patients. The detection of a preoperative unilateral VFP altered neither the indication for operation nor the extent of surgical resection. Data from these 13 patients are displayed in Table I. Postoperative laryngoscopy. Results of postoperative laryngoscopy are displayed in Table II. Sixty-eight patients (9.8%) developed a new onset VFP. Of these 68 patients, 13 were asymptomatic, whereas 55 complained about symptoms that suggested a VFP immediately after operation. None of the 13 asymptomatic patients underwent logopedic counseling; 24 of the 55 symptomatic patients underwent logopedic examination with a phoniatric and neuro-larnygeal examination and subsequent speech therapy, which resulted in a recovery of voice and VF mobility in 17 of them. None of our patients required vocal fold medialization by injection or thyroplasty. Five patients died within 6 months of operation and before follow-up. One patient died during the hospital stay as a result of mediastinitis and consecutive sepsis, 3 patients died from progression of malignant disease, and 1 patient died from cardiac insufficiency; the latter patient who suffered from
0/25 0/25 n.r. 0 VFM, vocal fold motion; postop., postoperative; n.r., not recorded; d, patients died before follow-up with persistent bilateral RLN palsy. *Preoperative and postoperative symptoms and results of laryngoscopy in 630 of the 695 patients who underwent initial thyroid surgery. †No additional pathology detectable when compared with preoperative laryngoscopy.
1/1 1/1 0/1 0 1/10 5/10 0/10 0 13/39 36/39 7/39 [2d/7] 6† 57/544 n.r. n.r. 1
0/4 4/4 3/4 [2d/3] 0
623 25 1 10
bilateral palsy required tracheotomy within the postoperative setting. VFP was considered permanent in these patients. Postoperative new development of VFP was permanent in 12 of the 695 patients (1.8%). All patients had obvious symptoms that suggested VFP immediately after operation. Postoperative new onset of VFP was transient in 56 of the 695 patients (8.1%). Follow-up revealed a transient VFP in all asymptomatic patients. The correlation between postoperative voice changes and permanent VF palsies proved to be significant (P ⬍ .001). Initial versus reoperative thyroid surgery: VFP was permanent in 10 of the 630 patients who underwent initial thyroid surgery (1.6%), whereas VF mobility recovered in 44 of the 630 patients (7.0%) (Table III). VFP was permanent in 2 of the 65 patients who underwent reoperative thyroid surgery (3.1%), whereas VF mobility recovered in 12 of the 65 patients (18.5%) (Table IV). The postoperative rate of transient as well as permanent VFPs was greater in patients who underwent reoperative surgery (P ⬍ .01). Benign versus malignant histopathology: Histopathology revealed benign disease in 644 of the 695 patients. Postoperative laryngoscopy demonstrated a new onset of VFP in 57 of the 644 patients (8.9%), which was permanent in 8 patients (1.2%). Malignancy was verified by histology in 51 of the 695 patients. Postoperative laryngoscopy demonstrated new onset VFP in 11 of the 51 of these patients (21.6%), which was permanent in 4 of them (7.8%). The incidence of pathologic findings at postoperative laryngoscopy, as well as the incidence of permanent VFPs, was greater in patients with malignant disorders than in those with benign disorders (P ⬍ .01).
Table III. Preoperative and postoperative laryngoscopy in patients who underwent initial thyroid surgery*
VFM, vocal fold motion.
4
86.2%
39
589
544
7.0% 1.6% 0.9% 0.4% 3.7%
Preoperative normal laryngoscopy (n ⫽ 623) Preoperative symptoms Postoperative symptoms Permanent VFP at follow-up Preoperative laryngoscopy pathologic (n ⫽ 7)
48 11 6 3 25
Postop. laryngoscopy Postop. laryngoscopy unilateral decreased bilateral decreased No postop. VFM VFM laryngoscopy
Percentage
Postop. normal Postop. laryngoscopy Postop. laryngoscopy laryngoscopy unilateral VFP bilateral VFP
Unilateral VFP Reduced unilateral VFM Bilateral VFP Bilateral reduced VFM Refusing examination because of no symptoms suggestive for VFP Normal
Number of patients
Summary
Table II. Results of postoperative laryngoscopy in patients with a normal examination before operation
10 permanent VFP 7
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2 permanent VFP 7 1 0/2 0/2 0/2 0 postop., postoperative; n.r., not recorded; d, patients died before follow-up with persistent bilateral RLN palsy. *Preoperative and postoperative symptoms and results of laryngoscopy in 65 patients who underwent reoperation. †No additional pathology detectable when compared with preoperative laryngoscopy.
0/1 0/1 0/1 0 4/9 9/9 1/9 5† 14/45 n.r. n.r.
1/2 2/2 1d/2 0
9 45
2
1
2
0
59
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Preoperative normal laryngoscopy (n ⫽ 59) Preoperative symptoms Postoperative symptoms Permanent VFP at follow up Preoperative laryngoscopy pathologic (n ⫽ 6)
Postop. laryngoscopy bilateral decreased VFM Postop. laryngoscopy unilateral decreased VFM Postop. laryngoscopy bilateral VFP Postop. laryngoscopy unilateral VFP Postop. normal laryngoscopy
Table IV. Preoperative and postoperative laryngoscopy in patients who underwent reoperative thyroid surgery*
No postop. laryngoscopy
Summary
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DISCUSSION The preoperative knowledge of a VFP enables appropriate counseling, which can outline a plan for the extent of operation and, furthermore, will facilitate dissection on the affected side and will enhance careful dissection on the opposite side.1,4,8,9 Especially in patients with a suspected or proven thyroid malignancy, the preoperative detection of a VFP will lead to additional diagnostic testing to evaluate an infiltration of adjacent structures. The results of the current study demonstrate that a preoperative laryngoscopy is justified in all patients who undergo reoperative surgery, those who have a suspected or proven malignant disease, as well as those who have symptoms that suggest a VFP. The routine use of preoperative laryngoscopy in all other patients seems to be of limited value. Of our 695 patients, 420 patients had no symptoms that suggested a VFP, no former neck explorations, and no suspected or proven malignancy. Preoperative laryngoscopy detected a VFP in only 1 patient (0.2%). If we had been unaware of the preoperative VFP in this patient, we would have performed a careful dissection on either side as usual and thus would have preserved the nonparalyzed RLN in all likelihood. These results suggest that a more selected approach to the use of preoperative laryngoscopy is feasible and acceptable. Patients who lack symptoms that suggest VFP, no former neck explorations, and no suspected or proven malignancy should not undergo routine preoperative laryngoscopy. Postoperative laryngoscopy was normal in 627 patients (90.2%). Unfortunately, we do not know how many of these patients had voice changes because only patients with a pathologic postoperative laryngoscopy underwent voice assessment and repeated laryngoscopy thereafter. Although an injury to the RLN is considered to be the main cause of voice change or breathing difficulties after thyroid surgery,10,11 these symptoms may also result from damage to the external branch of the superior laryngeal nerve (EBSLN)12,13 or not be related to the impaired RLN function at all.14-22 Indirect laryngoscopy often fails to detect other larynx pathologies except for VFPs, and an extensive logopedic and phoniatric evaluation is advocated. With respect to the findings of Musholt et al1 and Lombardi et al,24 we agree that voice changes and postoperative VF mobility must be considered as 2 separate entities. Additional investigation is mandatory, especially when postoperative indirect laryngoscopy is normal in symptomatic patients.1,3,23
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Unfortunately, a reliable assessment of voice changes after thyroid surgery is lacking.1,23,24 Netto et al23 suggested the use of routine videolaryngoscopy, voice analysis, and a vocal self-assessment questionnaire. This approach must be validated in the future. In the current study, of 55 symptomatic patients with a postoperative VFP, only 24 patients underwent logopedic examination and speech therapy. Moreover, none of the asymptomatic patients underwent logopedic examination and speech therapy immediately after surgery, and follow-up revealed recovery of voice and VF mobility in all patients. Asymptomatic patients do not require additional therapy. Most voice alterations that occur after thyroid and parathyroid surgery are self-limiting and of short duration.15-18 Whenever the laryngeal nerve and especially the RLN is visualized and is preserved intact on the affected side, which is preferably confirmed by intraoperative neuromonitoring, the patient should be reassured that a transient VFP is the most likely explanation, and that an increased likelihood of recovery exists. In patients with minor symptoms, laryngoscopy can even be deferred for some weeks or months and be performed if symptoms persist. In patients with major postoperative symptoms that suggest a VFP, such as severe hoarseness, dyspnea, or aspiration, postoperative laryngoscopy should be the first examination to identify individuals who need phoniatric or surgical therapy. In contrast, the patient’s desire to improve voice quality and thus improve his or her voice-related quality of life should be an indication for additional examination, with a consecutive conservative (speech therapy) or surgical therapy (medialization of a vocal fold) when VFP proves to be permanent.25,26 The routine use of postoperative laryngoscopy in all patients regardless of symptoms must be scrutinized. Routine postoperative laryngoscopy is often justified because of medico-legal concerns.1 In our opinion, obtaining informed consent of a patient who undergoes thyroid surgery, describing the dissection of the RLN in detail and (if available) the results of intraoperative neuromonitoring on either side within the operation record, and initiating a phoniatric examination in symptomatic patients is essential and will help to protect the surgeon from subsequent litigation. CONCLUSIONS First, although simple and quick, routine laryngoscopy seems to be inadequate as an instrument for
quality control by means of documenting the intact laryngeal function thoroughly. An objective, evidencebased approach to assess postoperative voice changes has yet to be validated on a wide population. Second, the incidence of VFPs in asymptomatic patients with a suspected benign disease and no previous neck surgery was extremely low and did not alter the extent of operation. Routine preoperative laryngoscopy in this subgroup of patients seems to be of limited value. Third, postoperative VFP was transient in all asymptomatic patients, and no patients underwent phoniatric/logopedic therapy. Because it is impossible to improve on the well-being of an asymptomatic patient, one may question the necessity of performing routine laryngoscopy in patients with no obvious or perceptible symptoms. Fourth, we should pay closer attention to complaints of voice changes, especially when these symptoms do not translate into objective findings at postoperative laryngoscopy. EBSLN palsy must be excluded, and thus, additional assessment is warranted. REFERENCES 1. Musholt TJ, Musholt PB, Garm J, Napiontek U, Keilmann A. Changes of the speaking and singing voice after thyroid or parathyroid surgery. Surgery 2006;140:978-88. 2. AWMF-Leitlinien-Register Nr.003/002. Guideline for the therapy of benign thyroid diseases; Grundlagen der Chirurgie G 80, Beilage zu: Mitteilungen der Dt. Ges. f. Chirurgie, 27. Jg., Nr. 3, Stuttgart, July 1998. 3. Steurer M, Passler C, Denk DM, Schneider B, Niederle B, Bigenzahn W. Advantages of recurrent laryngeal nerve identification in thyroidectomy and parathyroidectomy and the importance of preoperative and postoperative laryngoscopic examination in more than 1000 nerves at risk. Laryngoscope 2002;112:124-33. 4. Farrag TY, Samlan RA, Lin FR, Tufano RP. The utility of evaluating true vocal fold motion before thyroid surgery. Laryngoscope 2006;116:235-8. 5. AACE/AME Taskforce on Thyroid Nodules. American Association of Clinical Endocrinologists and Associazione Medici Endocrinologi medical guidelines for clinical practice for the diagnosis and management of thyroid nodules. Endocr Pract 2006;12:63-102. 6. British Association of Thyroid & Endocrine Surgeons. Surgical treatment of diseases of the thyroid gland. Available from: http://www.baes.info. 7. German Society of Surgery. [Guideline for the therapy of benign thyroid diseases]. Mitteilung der Deutschen Gesellschaft für Chirurgie 1998;27:G80. 8. Randolph GW, Kamani D. The importance of preoperative laryngoscopy in patients undergoing thyroidectomy: voice, vocal cord function, and the preoperative detection of invasive thyroid malignancy. Surgery 2006;139:357-62. 9. Erbil Y, Barbaros U, Issever H, Borucu I, Salmaslıog˘lu A, Mete Ö, et al. Predictive factors for recurrent laryngeal nerve palsy and hypoparathyroidism after thyroid surgery. Clin Otolaryngol 2007;32:32-7. 10. Dralle H, Kruse E, Hamelmann WH, Grond S, Neumann HJ, Sekulla C, et al. [Not all vocal cord failure following
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11.
12.
13. 14.
15.
16.
17.
18.
thyroid surgery is recurrent paresis due to damage during operation. Statement of the German Interdisciplinary Study Group on Intraoperative Neuromonitoring of Thyroid Surgery concerning recurring paresis due to intubation]. Chirurg 2004;75:810-22. Sinagra DL, Montesinos MR, Tacchi VA, Moreno JC, Falco JE, Mezzadri NA, et al. Voice changes after thyroidectomy without recurrent laryngeal nerve injury. J Am Coll Surg 2004;199:556-60. Cernea CR, Ferraz AR, Furlani J, Monteiro S, Nishio S, Hojaij FC, et al. Identification of the external branch of the superior laryngeal nerve during thyroidectomy. Am J Surg 1992;164:634-9. Teitelbaum BJ, Wenig BL. Superior laryngeal nerve injury from thyroid surgery. Head Neck 1995;17:36-40. Yeung P, Erskine C, Mathews P, Crowe PJ. Voice changes and thyroid surgery: is pre-operative indirect laryngoscopy necessary? Aust N Z J Surg 1999;69:632-4. Hong KH, Kim YK. Phonatory characteristics of patients undergoing thyroidectomy without laryngeal nerve injury. Otolaryngol Head Neck Surg 1997;117:399-404. Debruyne F, Ostyn F, Delaere P, Wellens W. Acoustic analysis of the speaking voice after thyroidectomy. J Voice 1997; 11:479-82. McIvor NP, Flint DJ, Gillibrand J, Morton RP. Thyroid surgery and voice-related outcomes. Aust N Z J Surg 2000; 70:179-83. Stojadinovic A, Shaha AR, Orlikoff RF, Nissan A, Kornak MF, Singh B, et al. Prospective functional voice assessment
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19.
20.
21.
22.
23.
24.
25. 26.
in patients undergoing thyroid surgery. Ann Surg 2002; 236:823-32. Jansson S, Tisell LE, Hagne I, Sanner E, Stenborg R, Svensson P. Partial superior laryngeal nerve (SLN) lesions before and after thyroid surgery. World J Surg 1988;12:522-7. Prim MP, de Diego JI, Hardisson D, Madero R, Gavilan J. Factors related to nerve injury and hypocalcemia in thyroid gland surgery. Otolaryngol Head Neck Surg 2001;124:111-4. Pereira JA, Girvent M, Sancho JJ, Parada C, Sitges-Serra A. Prevalence of long-term upper aerodigestive symptoms after uncomplicated bilateral thyroidectomy. Surgery 2003;133: 318-22. Kark AE, Kissin MW, Auerbach R, Meikle M. Voice changes after thyroidectomy: role of the external laryngeal nerve. Br Med J (Clin Res Ed) 1984;289:1412-5. de Pedro Netto I, Fae A, Vartanian JG, Barros AP, Correia LM, Toledo RN, et al. Voice and vocal self-assessment after thyroidectomy. Head Neck 2006;28:1106-14. Lombardi CP, Raffaelli M, D’alatri L, Marchese MR, Rigante M, Paludetti G, et al. Voice and swallowing changes after thyroidectomy in patients without inferior laryngeal nerve injuries. Surgery 2006;140:1026-32. Schulte KM, Roher HD. [Medico-legal aspects of thyroid surgery]. Chirurg 1999;70:1131-8. Hartl DM, Travagli JP, Leboulleux S, Baudin E, Brasnu DF, Schlumberger M. Clinical review: current concepts in the management of unilateral recurrent laryngeal nerve paralysis after thyroid surgery. J Clin Endocrinol Metab 2005 May;90(5):3084-8.
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DISCUSSION Dr Keith S. Heller (Lake Success, New York): I would like to congratulate you for finally providing real data on which to make recommendations. Because for so long we have been hearing absolutes that “you must” and “you should” and “you should never,” which was never based on data. So it is a wonderful study. A question: In the group that did have, not the asymptomatic group post op because clearly if you hadn’t looked you wouldn’t have known and nobody would be the wiser, but in the group who were symptomatic, and particularly in the group with permanent vocal paralysis post op, can you correlate that with surgical findings? Did you know at the time of surgery that this nerve was in jeopardy? And can you then sort out the cases in which postoperative laryngoscopy really came as a surprise to you? But thank you for this great study. Dr K. Schlosser (Marburg, Germany): It was in approximately 50 to 60% of cases that we suspected a vocal fold palsy. As you could see, we did surgery on a large population who also underwent surgery for a malignant thyroid. And in some of these cases, I don’t know the exact number, the recurrent laryngeal nerve had to be resected because of invasion. So in these cases, it was already clear that they will have symptoms and that they will have to undergo logopedic therapy. In cases where intraoperative neuromonitoring was performed and we achieved no signal, well, we suspected nerve damage. However, we usually visualize the nerve in its whole entity, so we never cut it by just not seeing it. Dr John S. Kukora (Abington, Pennsylvania): I very much appreciate the effort and diligence with which you did this study. I have for most of my career since I have been in the Philadelphia area used preoperative laryngoscopy to document the lay of the land before I have operated. I would say that I have found it useful because a lot of people come with symptoms that are in fact referrable to atrophy of their vocal cords from age, from gastroesophageal reflux that creates voice changes. And knowing that the cords move, I can direct these people sometimes to otolaryngologists rather than feeling obligated to take out perhaps a small and clearly benign thyroid nodule for which they are referred. So I think there is some value in the assessment of some patients’ symptoms irrespective of just the issue of the thyroid surgery. On the other hand, I have only found one asymptomatic patient in 20 years who had a paralyzed vocal cord. Given the fact that this man was an attorney who had a papillary thyroid cancer, I really
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did appreciate finding it, because I knew that in my environment I would have had a friendly comment from an attorney that I probably caused that at the time of surgery. I would say that there is an easy way to do this, and it is using a flexible laryngoscope and instead of putting it through the nose just have the patient hold their tongue and slide it over the back of the tongue and have them say “E” and “A” a couple of times. And you can do this as quick as you can listen to their heart sounds. But again I don’t know that it is necessarily cost effective if this is going to have a charge associated with it. And I think depending on your landscape you may or may not want to do this. But I do appreciate your comments. I would ask you, though, what is your definition of symptomatic either pre op or post op by which you decided to apply this technology? Dr K. Schlosser (Marburg, Germany): What we really miss is a manual to assess what a symptomatic patient is. And in the last meeting of this AAES, Dr. Musholt was here and presented a great work concerning exactly this point. And I think we should ask the patients to make a vocal self assessment test and also try to find out if they have hoarseness, even though they say they are asymptomatic. We also have to conduct a manual how to define an asymptomatic patient. In this study, we conducted the patient to be symptomatic when he says “My voice changed” or if hoarseness was obvious or if the patient claims that he developed dyspnea within the last month, or such things. But it was not on a regular manual. Dr Samuel K. Snyder (Temple, Texas): Thank you for presenting this very large and important study. I am interested in that, also, in trying to evaluate this from a nerve monitoring point of view. I heard you indicate that you used it in some of the patients. And that was one of my questions, how often did you use nerve monitoring? Did you find that useful not only in predicting which nerves were injured but, on the flip side, which nerves are normal? Because from my experience in hundreds of these patients, if the nerve monitor is completely normal, those are the ones that have the normal post op laryngoscopy. And that is another measure, I think, that we can use to maybe avoid having to do postoperative laryngoscopy. Dr K. Schlosser (Marburg, Germany): As you can see, the study data is a little older. We are currently actualizing our database. But it goes up to December 1999. And by that time, between 1995 and 1999, we didn’t perform regular intraoperative
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nerve monitoring. Now we do. Since 2001, we do it in every patient. And our results are as you said. Dr William B. Inabnet, III (New York, New York): Given Dr Kukora’s comments, maybe we should add one of the indications to laryngoscopy is being an attorney. Maybe that should be on the list of indications. A couple of questions. Could you please clarify how you define asymptomatic? Because up to 30 or 40% of patients will have some sort of voice change, they may not have hoarseness but they may have a change in pitch, et cetera. Secondly, it looks like you did six month laryngoscopy in all of these patients. Did you see evidence of external branch laryngeal nerve injury? And what you see on laryngoscopy is a tilt towards the contralateral side of the nerve that was injured. And it is very difficult to diagnose in laryngoscopy. But were you able to appreciate that on your six month study? Dr K. Schlosser (Marburg, Germany): I totally agree with you that simple laryngoscopy, and by that time it was indirect laryngoscopy in all of these patients, is not the tool for quality control to be chosen. In patients complaining about voice changes you have to perform a flexible laryngoscopy and in a patient who has a normal result within this study, but symptoms you need to perform a distinct further logopedic examination for this. And you can’t perform this as a surgeon. It is not our field, especially when not the surgeon who had performed the surgery. Well, you would say laryngoscopy was normal and that is it, it will normalize. Well, it will in most of the cases. But there are patients who will have an external branch of the superior laryngeal nerve injury and you might miss this by laryngoscopy. And if the patient is symptomatic, that means decrease in pitch and all the other signs that makes a patient symptomatic, this will not be found by a simple laryngoscopy, right? Then you have to go and and send the patient to an otolaryngologist. Dr Thierry Defechereux (Liege, Belgium): Maybe I missed that point in your presentation. But did you mention in your data the number of patients who had a symptomatic voice after we do surgery and then proceed identifying new preoperative exams? Did you detect nerve palsies after previous surgery in an asymptomatic patient? This might influence your redo-surgery, of course. And I would like to know if you got this data.
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Dr K. Schlosser (Marburg, Germany): You mean within preoperative laryngoscopy? Right. There were 13 patients who had a vocal cord palsy prior to surgery and six of them who had a previous surgery ahead of this. And out of these six patients, there were three symptomatic and another three that were asymptomatic. But that was mainly because these three patients had underwent logopedic therapy after their initial surgery where they developed their vocal cord palsy. Dr Jeffrey A. Van Lier Ribbink (Scottsdale, Arizona): Clearly the more compulsive, I think, we are at looking for voice changes after thyroid and parathyroid surgery, and clearly the more sophisticated techniques we look at that, we are finding that a higher incidence of patients do have voice changes. When I read the literature, almost every study I read states that whatever group is looking at their experience has a less than 1% risk of hoarseness. Should we even accept this anymore in these studies? It seems like perhaps their only method of determining their less than 1% chance of hoarseness is talking to the patient and seeing how they sound. Dr K. Schlosser (Marburg, Germany): On one hand, true. On the other, no. First I want to say that I don’t appreciate if the surgeon who did perform the surgery performs the laryngoscopy examination. Because I don’t know if everybody can free oneself for the opinion and look inside and you might see a slight movement and then claim “well, this is not a complete vocal cord palsy”. If you want to do such an examination as a quality tool, then it has to be done by somebody independent of this surgery group first. Second, if there is a patient who is asymptomatic, that means with really no hoarseness, really no dyspnea, what can you do? You cannot make an asymptomatic patient better. So I think there is no need to further examine these patients. Dr Collin J. Weber (Atlanta, Georgia): I agree wholeheartedly with what Dr Schlosser just said. My take on this in my personal practice is I do not do the laryngoscopy myself because I think it is self serving. I work very closely with two or three of our ENT folks who do this for me on a day’s notice. It is an independent evaluation. I know a lot of you may disagree with that, but that is how I do it.