Diagnostic Laryngeal Electromyography: The Wake Forest Experience 1995–1999

BACKGROUND:

Laryngeal electromyography (LEMG) is a valuable diagnostic/prognostic test for patients with suspected laryngeal neuromuscular disorders.

OBJECTIVE:

To report our experience with diagnostic LEMG at the Center for voice Disorders of Wake Forest University and to evaluate the impact of LEMG on clinical management.

METHODS:

Retrospective chart review of 415 patients who underwent diagnostic LEMG over a 5-year period (1995–1999).

RESULTS:

Of 415 studies, 83% (346 of 415) were abnormal, indicating a neuropathic process. LEMG results altered the diagnostic evaluation (eg, the type of radiographic imaging) in 11% (46 of 415) of the patients. Unexpected LEMG findings (eg, contralateral neuropathy) were found in 26% (107 of 415) of the patients, and LEMG results differentiated vocal fold paralysis from fixation in 12% (49 of 415). Finally, LEMG results altered the clinical management (eg, changed the timing and/or type of surgical procedure) in 40% (166 of 415) of the patients.

CONCLUSIONS:

LEMG is a valuable diagnostic test that aids the clinician in the diagnosis and management of laryngeal neuromuscular disorders.

Pulsed Dye Laser Treatment of Laryngeal Granulomas

Laryngeal granulomas are effectively treated with antireflux therapy and speech therapy. Failure to respond leads to treatment with Botox or surgical excision. We report on the use of the pulsed dye laser for treating chronic granulomas that do not respond to standard therapy. We performed a retrospective review from September 2002 to September 2003. Patients identified with chronic granulomas that were not responding to standard therapy were treated in our office with the pulsed dye laser. Ten patients were identified; the mean age was 58 years. Two patients underwent more than one pulsed dye laser treatment. Five of the 10 had resolution of their lesions, and 3 had a partial response. Two were unchanged. The average follow-up was 6 months, and there were no complications. We conclude that in-office use of the pulsed dye laser is a relatively safe and effective method for treating laryngeal granulomas that do not respond to antireflux therapy and speech therapy.

Intraobserver and Interobserver Reliability in Laryngopharyngeal Sensory Discrimination Thresholds: A Pilot Study

Objectives:

Laryngopharyngeal sensory discrimination threshold (LPSDT) testing is a method used to detect sensory deficits in patients in whom swallowing disorders are suspected. LPSDTs have been used to stratify patient risk status with regard to aspiration and to guide dietary management. The aim of this pilot study was to evaluate the intraobserver and interobserver reliability of LPSDT testing among a group of examiners with differing levels of testing experience.

Methods:

Twenty-seven healthy volunteers were enrolled in the study to elicit LPSDTs for intraobserver and interobserver reliability measurements. The examiners represented 3 levels of testing experience: An attending laryngologist, a laryngology fellow, and an otolaryngology resident. With the examiners blinded to test results, each subject was examined twice by one examiner and once by a different examiner in an alternating fashion.

Results:

Six subjects were unable to tolerate the examinations because of coughing and gagging. Spearman rank correlations revealed strong intraobserver reliability for the experienced endoscopists (ie, attending and fellow) but poor reliability for the novice endoscopist (ie, resident). Poor interobserver reliability regardless of endoscopy experience was found. Eighteen percent of the participants demonstrated LPSDTs of more than 4.0 mm Hg (above normal).

Conclusions:

1) Intraobserver reliability was good for experienced endoscopists. 2) Interobserver LPSDT agreement between endoscopists was poor. 3) Eighteen percent of the subjects demonstrated elevated LPSDT thresholds of more than 4 mm Hg.

Hands-on Training Methods for Vocal Fold Injection Education

Objectives:

Vocal fold injection (VFI) in the office setting and in the operating room is becoming increasingly popular. Most training programs fail to educate residents in performing these injections. In this report, we describe novel and effective teaching tools that provide real-life simulation of VFI for the education of residents and otolaryngologists in practice.

Methods:

Equipment was developed to allow the use of excised fresh cadaver larynges to simulate peroral VFI in a life-sized model of the human head and neck. A separate setup was also developed for use of a laryngoscope holder and cadaver larynges to simulate microlaryngoscopy VFI. Each of these VFI training setups allows the student to perform and practice VFI in a simulated setting with physical and anatomic constraints and laryngeal anatomy similar to those of real-life VFI. The use of fresh cadaver larynges allows the user to have a realistic feel of actual injection. A visual analog scale was used to measure the participants' comfort levels with the peroral and microlaryngoscopic injection techniques before and after the workshop.

Results:

Pre-workshop and post-workshop surveys were collected from 22 of the VFI course participants. The mean comfort levels for VFI prior to the workshop were 22 for peroral VFI and 69 for microlaryngoscopy VFI (0 = not comfortable at all and 100 = very comfortable). The post-workshop comfort levels were 52 for peroral VFI and 85 for microlaryngoscopy VFI. The differences in the pre- and post-workshop comfort level scores for each VFI technique were significant (microlaryngoscopy, p = .001; peroral, p <0001).

Conclusions:

The use of VFI simulations appears to improve surgeon comfort level with injection techniques. The described training simulations may be useful for allowing residents and practicing otolaryngologists to learn VFI before attempting these techniques on actual patients.

Cost Savings of Unsedated Office-Based Laser Surgery for Laryngeal Papillomas

Objectives:

Unsedated office-based laryngeal laser surgery (UOLS) is now an effective alternative to traditional operating room-based suspension microdirect laryngoscopy under general anesthesia. This procedure includes pulsed dye laser (PDL) treatment of recurrent respiratory papillomas, granulomas, leukoplakia, and polypoid degeneration. The objective of this study was to determine the magnitude of the cost savings derived by moving these types of procedures from the operating room to the office setting.

Methods:

Retrospective cost-identification analysis was performed by comparing the billing records of patients who underwent surgical laser treatment for recurrent respiratory papillomatosis in the operating room to the costs and charges for patients who underwent similar procedures with the in-office PDL.

Results:

In performing surgery with the PDL in the office, the average cost savings was more than $5,000 per case. Current reimbursement rates do not cover the cost of performing UOLS.

Conclusions:

The potential cost savings of UOLS are tremendous; however, at present significant financial disincentives prevent proliferation of this technology.

Patient Tolerance of In-Office Pulsed Dye Laser Treatments to the Upper Aerodigestive Tract

INTRODUCTION: Recent advances in technology have facilitated a movement toward unsedated in-office treatment of laryngeal, tracheal, and esophageal lesions. The objective of this study was to determine patient tolerance of inoffice pulsed-dye laser (PDL) treatment of upper aerodigestive tract pathoses via the transnasal esophagoscope.

METHODS: Three hundred twenty-eight unsedated in-office PDL cases were performed at a university-based tertiary referral center in 131 patients. These procedures were performed for various upper aerodigestive pathoses, including recurrent respiratory papillomatosis, chronic granulomas, and recurrent leukoplakia. Eighty-nine subjects completed a phone survey concerning their discomfort level after the PDL procedure. They were also asked specific questions about recovery time, pain medication, and preference of operating room versus inoffice procedures.

RESULTS: The average comfort score was 7.4 (10 being minimal discomfort). Eighty-four percent did not use any pain medication; 87% stated that, if possible, they would prefer to undergo unsedated inoffice procedures rather than surgeries under general anesthesia for further treatment of their upper aerodigestive tract pathosis.

CONCLUSIONS: Unsedated transnasal treatment of upper aerodigestive tract pathoses is readily accepted and well-tolerated by otolaryngology patients. Patients overwhelmingly prefer the inoffice PDL over surgeries under general anesthesia.

Revision Gore-Tex Medialization Laryngoplasty

OBJECTIVE: To evaluate the indications, results, and safety of revision Gore-Tex medialization laryngoplasty (GML).

METHODS: A retrospective chart review of 156 patients that underwent GML procedures between the years 1998–2002. Study population consisted of those patients who required revision surgery for any reason.

RESULTS: Sixteen patients required 22 revision procedures. Indications for revision were divided into 2 groups, complications and glottal closure problems. Complications included extruded or displaced implants (n = 4). The most common glottal closure problem was undercorrection (n = 9). Others included anterior overcorrection (n = 1) and persistent posterior glottal gap (n = 2). Revision procedures included GML (n = 9), injection augmentation (n = 9), endoscopic implant removal (n = 2), and arytenoid adduction (n = 2). In patients with glottal closure problems, the GCI improved in all 10 and the voice rating scale improved in 9.

CONCLUSION: Reasons for revision of GML are variable, the most common being undercorrection. A variety of safe, effective revision techniques are available with a high success rate.

Office-Based Laryngeal Laser Surgery: A Review of 443 Cases Using Three Wavelengths

BACKGROUND: Unsedated office-based laser surgery (UOLS) of the larynx and trachea has significantly improved the treatment options for patients with laryngotracheal pathology including recurrent respiratory papillomas, granulomas, leukoplakia, and polypoid degeneration. UOLS delivered by flexible endoscopes has dramatically impacted office-based surgery by reducing the time, costs, and morbidity of surgery.

OBJECTIVES: To review our experience with 443 laryngotracheal cases treated by UOLS.

METHODS: The laser logbooks at the Center for Voice and Swallowing Disorders were reviewed for UOLS, and the medical and laryngological histories were detailed, as were the treatment modalities, frequencies, and complications.

RESULTS: Of the 443 cases, 406 were performed with the pulsed-dye laser, 10 with the carbon-dioxide laser, and 27 with the thulium: yttrium-aluminum-garnet laser. There were no significant complications in this series. A review of indications and wavelength selection criteria is presented.

CONCLUSION: Unsedated, office-based, upper aerodigestive tract laser surgery appears to be a safe and effective treatment option for many patients with laryngotracheal pathology.

Mechanical Modeling of the Human Cricoid Cartilage Using Computer-Aided Design: Applications in Airway Balloon Dilation Research

OBJECTIVES

Balloon dilation is generally considered first-line treatment for airway stenosis. Some dilation systems utilize a compliant balloon that can conform around rigid structures. Others use a noncompliant balloon that does not conform, allowing for dilation of more rigid stenoses. We hypothesized that subglottic dilation with a noncompliant balloon increases the likelihood of fracture of the cricoid when compared to a compliant balloon.

METHODS

Three fresh human cricoid cartilages were placed in a universal testing system to determine the expansile force necessary for cricoid fracture. Using these data, a 3D printer was used to construct a synthetic cricoid model possessing near identical physical characteristics to the human cricoid. Simulated dilation was then performed on the model using a compliant and a noncompliant balloon.

RESULTS

Human cricoid fracture occurred at 97.25 N (SD = 8.34), and the synthetic cricoid model fractured at 100.10 N (SD = 7.32). Both balloons fractured the model in every replicate experiment. Mean balloon internal pressure at fracture was 7.67 ATM (SD = 1.21) for the compliant balloon and 11.34 ATM (SD = 1.29) for the noncompliant balloon.

CONCLUSIONS

These data show that fracture of the cricoid is a valid concern in balloon dilation procedures where the balloon spans the subglottis. Furthermore, the hypothesis was rejected in that the compliant balloon system was at least as likely to fracture the cricoid model as the noncompliant.

Tracheal Size Variability Is Associated With Sex

Purpose:

Whereas selection of endotracheal tube (ETT) size in pediatric patients benefits from predictive nomograms, adult ETT sizing is relatively arbitrary. We sought to determine associations between cervical tracheal cross-sectional area (CTCSA) and clinical variables.

Methods:

One hundred thirty-two consecutive patients undergoing noncontrasted chest computed tomography (CT) at a single tertiary care institution from January 2010 to June 2011 were reviewed. Patients with improper CT technique, endotracheal intubation, and pulmonary/tracheal pathology were excluded. Tracheal luminal diameters in anteroposterior (D1) and transverse (D2) were measured 2 cm inferior to the cricoid and used to determine CTCSA = π*D1*D2*¼. The demographic variables of age, height, weight, and body mass index (BMI) were tested for association with CTCSA by Spearman correlation. Wilcoxon rank-sum test was used to compare CTCSA by race and sex. Multivariate linear regression was performed including all clinical variables.

Results:

There were 91 patients who met inclusion criteria. There was no correlation between age, weight, or BMI and CTCSA. There was a significant positive correlation between patient height and CTCSA ( P = .001, R = 0.35); however, this was confounded by sex. Female patients had significantly smaller CTCSA (mean = 241 mm2) compared to male patients (mean = 349 mm2, P < .001). Multivariate linear regression stratified by sex revealed that height is correlated with CTCSA only in males ( P = .028). Males also had more variability in CTCSA (SD 118.6) compared to females (SD 65.5).

Conclusion:

Our data suggest that selection of ETT size in male patients should include height as a predictive factor. For female patients, it may be appropriate to select a uniformly smaller diameter ETT size.

Biomechanical changes from long-term freezer storage and cellular reduction of tracheal scaffoldings

OBJECTIVES/HYPOTHESIS

To determine structural biomechanical changes in tracheal scaffolds resulting from cellular reduction and storage at -80(o) C.

STUDY DESIGN

Laboratory-based study.

METHODS

Forty-four rabbit tracheal segments were separated into four treatment groups: untreated (group A, control), cellular-reduced (group B), storage at -80(o) C followed by cellular reduction (group C), and cellular-reduced followed by storage at -80(o) C (group D). Tracheal segments were subjected to uniaxial tension (n = 21) or compression (n = 23) using a universal testing machine to determine sutured tensile yield load and radial compressive strengths at 50% lumen occlusion. Mean differences among groups for tension and compression were compared by analysis of variance with post-hoc Tukey-Kramer test.

RESULTS

The untreated trachea (group A) demonstrated mean yield strength of 5.93 (± 1.65) N and compressive strength of 2.10 (± 0.51) N. Following treatment/storage, the tensile yield strength was not impaired (group B = 6.79 [± 1.58] N, C = 6.21 [± 1.40] N, D = 6.26 [± 1.18]; P > 0.10 each). Following cellular reduction, there was a significant reduction in compressive strength (group B = 0.44 N [± 0.13], P < 0.0001), but no further reduction due to storage (group C = 0.39 N [± 0.10]; P = 0.97 compared to group B).

CONCLUSION

The data suggest cellular reduction leads to loss of compressive strength. Freezing at -80°C (either before, or subsequent to cellular reduction) may be a viable storage method for tracheal grafts.

Thyroid ala perichondrial flaps for subglottic reconstruction

OBJECTIVES/HYPOTHESIS

Techniques available for reconstruction of the cricotracheal region in adults are currently suboptimal. We sought to 1) understand the anatomic basis for the thyroid ala perichondrial flap, 2) describe the technique of harvesting and intraluminal placement, and 3) learn the limitations of defects for which it can be used.

STUDY DESIGN

Cadaveric anatomical study.

METHODS

In fresh cadaveric specimens, the perichondrium of the outer layer of the thyroid cartilage was elevated by tracing the superior, medial, and lateral borders of each thyroid cartilage ala. The inferiorly based flap was then placed into the airway through the cricothyroid membrane. The extent of coverage was measured.

RESULTS

A total of 10 flaps were performed (6 male and 4 female). The average length of thyroid perichondrial flaps obtained was 1.67 cm. All flaps were able to completely cover the cricoid cartilage and extended to but did not cover the first tracheal ring. Once placed intraluminally, the flaps extended 2.4 cm below the vocal cords. Using both flaps enabled coverage of the entire anterior 180 degrees of the airway lumen in all specimens. There were no significant differences in male/female or right-sided/left-sided flaps.

CONCLUSIONS

The thyroid ala perichondrial flap is technically feasible and can provide coverage of anterior airway defects up to approximately 2.4 cm below the true vocal cords. This flap could enable transfer of vascularized tissue to aid in cricotracheal reconstruction.

Defining the biomechanical properties of the rabbit trachea

OBJECTIVES/HYPOTHESIS

Surgical advancements rely heavily on validated animal models. The New Zealand White (NZW) rabbit is a widely used model for airway research, including regenerative medicine applications. Currently, the biomechanical properties of the normal rabbit trachea are not known. Our objective was to define these properties to assist in the standardization and understanding of future airway research using this model.

STUDY DESIGN

Laboratory-based study.

METHODS

Fresh tracheas from four adult NZW rabbits were dissected into 20 segments. To examine the biomechanical properties, segments were subjected to uniaxial tension (n = 9) and compression (n = 11) testing. Yield and maximum load (tension) and force at 50% displacement (compression) were recorded, and differences between segments were examined using analysis of covariance.

RESULTS

Normative data for native rabbit trachea show mean maximum load = 6.44 newtons (N), yield load = 5.93 N, and compressive strength = 2.10 N. In addition to establishing the baseline measurements, statistically significant differences in tensile measures based on location along the trachea and diameter were identified. Proximal segments had significantly higher maximum load (P = .0029) and yield load (P = .0062) than distal segments. Association between diameter and both maximum load (P = .0139) and yield load (P = .0082) was observed.

CONCLUSIONS

The adult NZW rabbit trachea is intrinsically less able to withstand tensile and compressive forces, compared to other airway models such as sheep or cadaveric human. Establishment of normative values will enable future research into changes in tracheal biomechanical properties during regenerative medicine manipulation and processing.

Laryngeal Inflammation: Diagnosis and Treatment Challenges

Program Description:

Using an interactive format, panelists will discuss epidemiology, symptomatology, and co-morbid conditions contributing to laryngopharyngeal inflammation; diagnosis/differential diagnosis; challenges in diagnosing causative factors; addressing diagnostic challenges to define a treatment plan; current evidence; treatment challenges and impact of co-morbid conditions; and future research and management implications. The panel will consider “real world” patient management algorithms. The audience will help answer the following questions: What are the typical ‘challenges’ in diagnosing laryngopharyngeal inflammation? What diagnostic testing options should be employed? Which after first treatment failure? What are the common treatment pathways? What differential data should be considered? What healthcare costs impact options? When is referral recommended?

Educational Objectives:

1) Describe current practice trends on the diagnosis and management of laryngopharyngeal inflammation. 2) Recognize the common challenges in diagnosing laryngeal inflammation to define appropriate treatment strategies. 3) Evaluate current evidence-based literature supporting current diagnosis and treatment paradigms.

Practical Approach to Swallowing Problems

Program Description:

This miniseminar will present a practical approach to the evaluation of swallowing problems, one of the most common problems seen in otolaryngology practices. A combination of didactic teaching and case presentations will be used to illustrate appropriate workup of swallowing problems, including history, examination, and diagnostic tests. The use of swallowing evaluations, such as fluoroscopy, endoscopy, and manometry, will be discussed. Non-surgical and surgical approaches to managing swallowing problems, along with risks and benefits, will be presented.

Educational Objectives:

1) Identify a practical algorithm for the evaluation of swallowing problems. 2) Discuss the benefits of diagnostic tests for swallowing problems, including fluoroscopy, endoscopy, and manometry. 3) Apply the appropriate approach to non-surgical and surgical therapeutics for swallowing problems.

Microdebrider Complications in Laryngologic and Tracheal Surgery

Objectives:

There is no formal body of literature focusing on complications in laryngologic and airway surgery performed with microdebriders. Attendees can expect to: 1) Describe potential complications that may occur with microdebrider use during laryngologic and airway surgery. 2) Recognize which clinical situations are better suited to the use of the microdebrider. 3) Implement changes in clinical practice to improve operative safety when using the microdebrider in laryngologic and airway surgery.

Methods:

A literature review of microdebrider complications in otolaryngologic surgery was performed. A series of exemplary and illustrative cases seen by various surgeons in selected high volume laryngologic centers was confidentially solicited and is described.

Results:

Significant microdebrider complications are described, including severe hemorrhage, extensive tissue loss, and airway perforation, as well as ways to prevent and treat these complications.

Conclusions:

A thorough understanding of the microdebrider and its potential complications will improve surgical outcomes. Implications for Practice: Awareness of the risks and knowing when to use the microdebrider will allow the surgeon to successfully use this device in a safe and efficient manner.

Transnasal esophagoscopy

Since the mid 1900s, esophagoscopy has been performed under sedation or general anesthesia. With transnasal esophagoscopy (TNE), there has been a return to awake, in-office esophagoscopy. Technologic advances have allowed the advent of a ultrathin, flexible esophagoscope that is introduced transnasally, allowing esophagoscopy to be performed in unsedated patients. TNE correlates with conventional esophagoscopy (sedated, flexible esophagoscopy) in diagnostic capacity. Over time, as the benefits of TNE have become elucidated, the procedure has gained wider acceptance and continues to have its role in patient care defined.