Indirect laryngeal surgery in the clinical voice laboratory: The renewal of a lost art.

Abstract

Since the advent of precision instruments and safe techniques for direct laryngoscopic surgery under general anesthesia, indirect laryngeal surgery has become very uncommon. A review of the recent literature finds that few authors advocate indirect surgery under topical anesthesia, and many otolaryngologists dismiss this technique as being either of only historical interest or an idiosyncratic method practiced only by a handful of clinicians. The societal mandate for cost-effective healthcare and the availability of relatively low-cost, high-quality endoscopes and video equipment warrant a renewed and broader interest in this type of surgery. In this article, we review a series of 27 indirect surgical procedures performed under topical anesthesia in the clinical voice laboratory. We discuss the indications, outcomes, advantages, and disadvantages of this surgery, and we present a brief analysis of its cost-effectiveness. We conclude that indirect laryngeal surgery in the clinical voice laboratory is an effect ive, safe, efficient, and less costly alternative to some procedures routinely performed under general anesthesia.

Introduction

The two options for evaluating laryngeal pathology are an indirect mirror examination and an examination by endoscopy. Flexible fiberoptic endoscopes are routinely used in the outpatient clinic setting, and the use of rigid laryngeal endoscopes with angled lenses is becoming more commonplace. Direct laryngoscopy under general anesthesia in the operating room is routine in most cases when a detailed examination, biopsy, injection, or excision of a laryngeal lesion is undertaken.

The history of laryngology, and in particular laryngoscopy, is a colorful one. A review of the early attempts to develop reliable instrumentation and techniques for visualization of the larynx reveals that there have been several creative pioneers. In the first half of the 19th century, Bozzini, Babbington, Desmormeaux, and others experimented with a variety of devices for laryngeal examination. [1] In 1854, voice teacher Manuel Garcia viewed the glottis by reflecting light off a dental mirror, and this led others to begin applying the laryngeal mirror in clinical examinations. Morell MacKenzie further broadened the horizons of laryngology when he developed instruments for indirect laryngeal surgery.

As a result, interest in laryngology rapidly expanded, and during the latter part of the 19th century, rigid instruments for direct laryngoscopy were introduced and refined by such renowned endoscopists as Chevalier Jackson. Improvements in instrument design and the development of safe techniques for general anesthesia eventually led to the point where direct laryngeal surgery in large part supplanted indirect laryngeal surgery.

Both technological advances and societal priorities warrant a renewed interest in indirect laryngeal procedures. Chief among these factors are the availability of high-quality and relatively affordable endoscopes and video equipment, and the quest for cost-efficient healthcare. There are also inherent advantages to performing certain laryngeal procedures when the patient is upright and awake, such as the ability to assess voice when performing injection laryngoplasty and to observe vocal fold mobility when staging a tumor.

Researchers at a small number of centers have recognized the intrinsic advantages of this approach and have recently published series of reports on indirect laryngeal and pharyngeal examinations and procedures. [2-5] These reports have helped document the safety and efficiency of these techniques. Even so, utilization remains limited, and these techniques are not routinely taught in residency training programs. Further study will be necessary before these techniques can become established in the standard surgical armamentarium of the otolaryngologist-head and neck surgeon, rather than being considered nothing more than idiosyncratic methods employed by few practitioners.

The purpose of our report is to review a series of indirect procedures and help further define appropriate roles for these operations. We review the indications, outcomes, and complications of indirect surgery, and we present a brief cost-comparison analysis.

Materials and methods

Patients. We retrospectively reviewed the records of all patients who had undergone indirect procedures in the clinical voice laboratory at the University of Michigan from August 1995 through January 1999. In each case, we noted the indications, outcomes, and complications. We based our cost comparison on the experiences of two patients who had undergone an indirect biopsy shortly after a direct laryngoscopy and biopsy under general anesthesia. All patients had signed a standard operative permit, and this review was undertaken with the approval of the University of Michigan's Institutional Review Board.

Techniques. The techniques used for indirect laryngeal examination and surgery have been previously described. [2,5] The main features of these indirect techniques included the topical anesthetization of the oropharynx with 10% lidocaine spray, which was followed by an examination of the larynx and hypopharynx with a 70[degrees] rigid magnifying laryngoscope (Kay Elemetrics; Lincoln Park, NJ) or a 90[degrees] instrument (Richard Wolf Medical Instruments; Vernon Hills, Ill.), attached to a computer-integrated video-stroboscopy system (Kay Elemetrics). With the patient seated directly opposite the examiner, the larynx, hypopharynx, and trachea were anesthetized with a topical application of 4% lidocaine solution (figure 1). As appropriate for the particular procedure, a standard flexible laryngoscope could then be used for further examination around bulky lesions or into the pyriform sinuses or postcricoid region. When necessary, light intravenous sedation with small aliquots (0.5-mg increments) of midazolam t itrated to effect was administered to further suppress an active gag reflex during the anesthetization process.

Once topical anesthesia was sufficient and the initial examination was complete, the appropriate procedure was performed with the rigid magnifying laryngoscope and the videoendoscopy system. Biopsy specimens were taken with a curved laryngeal biopsy forceps. Scar division/excision was performed with the biopsy forceps, with or without an attached scalpel blade. Injection laryn-goplasties employed a Bruening's pressure syringe with a curved injection needle, and an orotracheal injection device was used for steroid injections of granulomata and for collagen injections. Figures 2A through 2C show the view through a 70[degrees] rigid endoscope during instillation of lidocaine, laryngeal biopsy, and injection laryngoplasty. Vital signs were monitored in patients who received light IV sedation. Patients were instructed not to eat or drink until normal sensation had returned to the larynx and pharynx.

Results

From August 1995 through January 1999, 27 indirect procedures were performed in the clinical voice laboratory on 24 patients. Twenty-six procedures were on the larynx and one on an adjacent hypopharyngeal lesion. They included 13 biopsies, eight injection laryngoplasties, three steroid injections, and three scar divisions/ excisions.

The 13 biopsies were of lesions suspicious for squamous cell carcinoma (table 1). The eight injection laryngoplasties were performed for the treatment of dysphonia secondary to unilateral vocal fold paralysis or vocal fold scarring; these eight cases included five Gelfoam injections, two Teflon injections, and one autologous collagen injection. Three granulomata were injected with steroid, and the three remaining procedures were performed to divide or excise posterior glottic scarring caused by long-term intubation. In one case, scar treatment was performed as an adjunct to a recently completed procedure under general anesthesia. Three patients required light IV sedation.

Sixteen procedures were performed in the voice laboratory rather than under general anesthesia solely because of the authors' preference for the efficiency and voice monitoring advantages of operating in the outpatient clinic on an awake and upright patient. The other 11 patients had been referred to the principal author by colleagues because these patients had a variety of reasons to avoid general anesthesia: Six patients had significant medical comorbidities; three patients had persistent suspicious lesions despite recent inconclusive biopsies via direct laryngoscopy; one patient had undergone a previous, unsuccessful attempt at direct laryngoscopy and biopsy of an anterior glottic lesion (which was unsuccessful because of the inability to visualize the anterior larynx under general anesthesia); and a remaining private-pay patient was concerned about cost.

Biopsies. All 13 indirect biopsies yielded adequate tissue for pathologic analysis. The diagnoses included six invasive squamous cell carcinomas, one carcinoma in situ, and one cellular atypia without frank carcinoma; five biopsies were negative (benign infectious or inflammatory lesions). The patient with cellular atypia was eventually found to have carcinoma in situ after undergoing a subsequent biopsy under general anesthesia. Prior to the indirect biopsy, this patient had already undergone an earlier biopsy under general anesthesia that was interpreted as carcinoma in situ despite the gross appearance of invasive squamous cell carcinoma.

Injection laryngoplasties. Seven of the eight injection laryngoplasties yielded satisfactory results. The remaining patient was scheduled for a repeat injection of Teflon because of a decline in voice strength in the months following the initial injection. It should be noted that laryngeal framework surgery and nerve transfer operations are the preferred methods of surgical rehabilitation of unilateral vocal fold paralysis at our institution.

We used the Teflon in two patients because one patient had metastatic lung carcinoma and a very limited life expectancy, and the other had extensive neck scarring from previous surgery and irradiation that precluded other options. Results of the Gelfoam injections were considered satisfactory if the patient experienced an increase in voice strength for at least 6 weeks afterward. After 6 weeks, a decline in strength is expected as the material is resorbed. The patient who was injected with autologous collagen experienced a sustained improvement in perceptual voice quality and voice-related quality of life (VRQOL), as determined by the V-RQOL measure, [6] at 14 months postinjection.

Steroid injections. Steroid injections were accomplished satisfactorily in all three patients, although one of the treated granulomata persisted despite antireflux measures and voice therapy.

Scar division/incision. Two of the three cases of posterior glottic scarring featured mature interarytenoid adhesion bands with obvious mucosally lined tracts posteriorly. These bands were easily divided, and the scar remnants were removed with cup forceps. Both patients had an improved airway and required no additional procedures.

The third patient had more extensive posterior commissure and interaryrenoid scarring. Examination in the clinic had demonstrated that this woman had bilateral vocal fold motion impairment caused by scarring, but it was unclear from that examination whether a mucosally lined tract existed posteriorly. She was taken to the operating room for a microlaryngoscopy 1 week prior to the indirect procedure, and examination under general anesthesia demonstrated scarring that had a mucosally lined tract posteriorly for most but not all of the inferior-to-superior length of the scar. Based on these findings, we felt that division of the scar in the midline wit a [CO.sub.2] laser was a reasonable initial attempt at treatment, and this did improve her passive arytenoid mobility intraoperatively. At the 1-week followup appointment, we observed that the patient had developed adhesions in the area of the scar division, and these adhesions were divided wit an angled forceps and the indirect technique. The woman experienced a subjective and visible improvement in her glottic airway from the combined treatment, and she was able to have her perioperative tracheotomy decannulated once the posterior glottis was completely healed.

All 27 procedures were generally well tolerated. Coughing was routinely encountered during the initial instillation of topical anesthetic, and sometimes during the latter stages of a procedure. No patient suffered laryngospasm. Patients were generally tolerant of the small amounts of blood-tinged sputum following most procedures and the pulling sensations experienced during some biopsies.

There was one significant complication, which occurred in a man who had undergone a biopsy of a large supraglottic mass. Approximately 24 hours following this procedure, he began to bleed from the biopsy site. In light of the bleeding and the large size of his supraglottic tumor, he underwent an urgent tracheotomy for airway management. The bleeding itself did not require further intervention, and the patient's subsequent definitive oncologic treatment outcome was not affected by the episode.

Cost comparison. Two patients in this series were biopsied in the voice laboratory shortly after they had undergone unsatisfactory biopsy procedures via direct laryngoscopy under general anesthesia. These two cases allowed us to make a cost comparison of the two modalities (table 2). As expected, the indirect procedures were considerably less expensive because there were no anesthesiologist, operating room, or recovery room costs.

Discussion

Historically, indirect laryngeal surgery was pioneered long before the development of adequate instrumentation and safe techniques for direct laryngoscopy and general anesthesia. Some modem practitioners might feel that the indirect techniques are only of historical interest. To the contrary, we consider them to be a lost art. Familiarity and facility with indirect laryngeal procedures can be a very valuable asset for the contemporary otolaryngologist--head and neck surgeon. This article provides evidence of the safety and versatility of these techniques, and it touches on the potentially large cost savings compared with similar direct laryngoscopic procedures.

The utility of these techniques for the individual surgeon will differ according to practice patterns, training, availability of instrumentation, and individual preferences regarding the roles for such operations. This series reflects the diversity in their utility, in that although the principal author performed all the procedures, our patients came from the practices of several different physicians, both inside and outside our institution.

Various contraindications to general anesthesia were the basis for employing the indirect procedure for all but one of the 11 patients who had been referred by other surgeons. In the other 16 cases, indirect procedures were performed on patients in the author's own practice, and this was done solely because of the recognized advantages that they have over direct procedures.

The most obvious advantage to using indirect techniques is the relative efficiency in expediting a diagnosis and, in some cases, treatment. Avoidance of general anesthesia and its associated risks is another good reason to consider an indirect approach. This is true for any patient, but in particular for those who have relative or absolute contraindications to general anesthesia.

There was only one significant complication in our series-delayed postoperative bleeding--but it was not considered to be directly related to the technique. For injection laryngoplasty, there is no doubt that the ability to actively assess the voice while the patient is upright and awake holds inherent advantages over the same procedure in a patient who is asleep and supine. Finally, although comparison data were available for only two patients, the potential cost savings are compelling.

Indirect laryngeal procedures do have their limitations, although they will likely be defined differently by each practitioner. We do not feel that excision of true vocal fold lesions or biopsy of suspicious sessile true vocal fold lesions should be approached in the indirect manner because the depth of the excision and the protection of adjacent mucosa are not adequately controlled. Microdirect laryngoscopy is preferred for such procedures. Also, although excellent tumor staging can be accomplished in most patients with a rigid or flexible endoscope under adequate topical anesthesia, [3] the inferior extent of some lesions in the hypopharynx can be difficult to assess in the voice laboratory. Evaluation of the esophagus is also deferred to the radiology suite or to the onset of a later surgical procedure for definitive lesion management. Other limitations include the fact that (1) there is a learning curve associated with becoming proficient at voice laboratory procedures, (2) proper instrumentation is not always available, and (3) some patients will simply prefer general anesthesia.

In conclusion, we believe that indirect laryngeal procedures in the clinical voice laboratory are an effective, safe, efficient, and less costly alternative to some procedures routinely performed via direct laryngoscopy under general anesthesia. Although the utility of these techniques will vary by surgeon, the ability to perform indirect procedures would be a valuable component of the surgical armamentarium of every contemporary otolaryngologist-- head and neck surgeon.

Acknowledgment

The authors thank Robert W. Bastian, MD, for introducing us to this lost art.

From the Department of Otolaryngology--Head and Neck Surgery, University of Michigan Medical Center, Ann Arbor.

Reprint requests: Norman D. Hogikyan, MD, Department of Otolaryngology, University of Michigan Medical Center, 1904 Taubman Center, 1500 E. Medical Center Dr., Ann Arbor, MI 48109-0312. Phone: [phone]; fax: [phone]; e-mail: [e-mail]

References

(1.) Karmody CS. The history of laryngology. In: Fried MP, ed. The Larynx: A Multidisciplinary Approach. Boston: Little, Brown, 1988:3-8.

(2.) Bastian RW, Delsupehe KG. Indirect larynx and pharynx surgery: A replacement for direct laryngoscopy. Laryngoscope 1996;106:1280-6.

(3.) Bastian RW, Collins SL, Kaniff T, Matz GJ. Indirect videolaryngoscopy versus direct endoscopy for larynx and pharynx cancer staging. Toward elimination of preliminary direct laryngoscopy. Ann Otol Rhinol Laryngol 1989;98:693-8.

(4.) Ford CN, Roy N, Sandage M, Bless DM. Rigid endoscopy for monitoring indirect vocal fold injection. Laryngoscope 1998;108:1584-6.

(5.) Hogikyan ND. Transnasal endoscopic examination of the subglottis and trachea using topical anesthesia in the otolaryngology clinic. Laryngoscope 1999;109:l170-3.

(6.) Hogikyan ND, Sethuraman G. Validation of an instrument to measure voice-related quality of life (V-RQOL). J Voice 1999;13:557-69.

                  Indirect surgical procedures performed
                     in the clinical voice laboratory
Procedure               No. patients
Biopsy                       13
Injection laryngoplasty       8
Steroid injection             3
Scar division/excision        3
                 Comparison of costs between indirect and
                  direct laryngeal examination and biopsy
                    in two patients who underwent both
                                procedures
                 Patient 1           Patient 2
                 Indirect     Direct Indirect     Direct
Laryngoscopy      $628.00    $628.00  $628.00    $628.00
Esophagoscopy       N/A       520.00    N/A       520.00
Surgeon's charge   628.00   1,148.00  628.00    1,148.00
Anesthesia/OR       N/A     2,926.59    N/A     2,644.19
Total             $628.00  $4,074.59  $628.00  $3,792.19