eMedicine Specialties > Otolaryngology and Facial Plastic Surgery > Laryngology

Vocal Fold Paralysis, Unilateral

Thomas L Carroll, MD, Assistant Professor, Department of Otolaryngology-Head and Neck Surgery, Tufts Medical Center, Tufts University School of Medicine
Clark A Rosen, MD, Director, University of Pittsburgh Voice Center; Associate Professor, Department of Otolaryngology and Communication Science and Disorders, University of Pittsburgh School of Medicine; Ryan J Soose, MD, Assistant Professor, Department of Otolaryngology, University of Pittsburgh Medical Center

Updated: Nov 6, 2008

Introduction

Unilateral vocal fold paralysis (UVFP) occurs from a dysfunction of the recurrent laryngeal or vagus nerve innervating the larynx. It causes a characteristic breathy voice often accompanied by swallowing disabilty, a weak cough, and the sensation of shortness of breath. This is a common cause of neurogenic hoarseness. When this paralysis is properly evaluated and treated, normal speaking voice is typically restored.

History of the Procedure

Unilateral vocal fold paralysis (UVFP) most commonly occurs following a surgical iatrogenic injury to the vagus or recurrent laryngeal nerve. Thus, a history of head and neck, skull base, brainstem or chest surgery should be obtained. Specifically, thyroidectomy, carotid endarterectomy, anterior cervical spine surgery, thoracic, or mediastinal surgery most often result in a presentation of unilateral vocal fold paralysis (UVFP).

The differential diagnosis for an acute unilateral vocal fold paralysis (UVFP) should always include recent upper respiratory tract or viral infection and recent intubation for any surgical procedure. Procedures aimed at restoring glottic competence include permanent and temporary vocal fold injections, as well as laryngeal framework surgery, including medialization laryngoplasty (type 1 thyroplasty) and arytenoid adduction or arytenopexy.

Problem

Normal vocal fold function is reliant on vocal fold glottal closure that results from bilateral adduction of the vocal folds. Normally, this vocal fold adduction behavior, in combination with subglottic airflow, induces vocal fold vibration. Unilateral vocal fold paralysis (UVFP) results in glottal incompetence, either partial or complete, resulting in a weak or absent vocal fold vibration that leads to dysphonia. Significant muscle tension is often seen in the larynx as a compensatory mechanism for the glottal gap. Patients with unilateral vocal fold paralysis (UVFP) often describe pain in the throat or neck after voice use, which is likely due to the excessive muscle tension. 

Etiology

• Surgical iatrogenic injuries resulting in vocal fold paralysis include thyroid surgery, anterior cervical disc surgery, carotid surgery, or chest surgery.
• Malignant invasion of either the vagus or recurrent laryngeal nerve can occur with skull base tumors, thyroid cancer, lung cancer, esophageal cancer, and metastases to the mediastinum (often observed with lung cancer primaries).
• Blunt trauma to the neck or chest.
• When a clear-cut etiology for the unilateral vocal fold paralysis (UVFP) is not found, it is classified as idiopathic. These cases can be attributed to a viral or inflammatory process, but this is usually a presumptive diagnosis.

Pathophysiology

Presentation

Patients with unilateral vocal fold paralysis (UVFP) typically present with a fairly sudden onset of breathy, weak, low-pitched dysphonia. In some cases, however, the dysphonia can be high-pitched because of a compensated lengthening of the vocal folds to achieve better glottic closure. Often, unilateral vocal fold paralysis (UVFP) is associated with dysphagia, specifically with liquids, because the resultant glottal incompetence can lead to aspiration. This is especially true if the unilateral vocal fold paralysis (UVFP) is due to a high vagal lesion that results in both a recurrent laryngeal nerve and superior laryngeal nerve palsy. The latter results in significant anesthesia of the pharynx, contributing to the patient's dysphagia and increased risk for aspiration.

Patients with unilateral vocal fold paralysis (UVFP) often report shortness of breath or a feeling of running out of air. Very little negative physiological impact upon pulmonary function actually occurs in patients with unilateral vocal fold paralysis (UVFP); however, because of the glottal incompetence, they experience significant air wasting and, thus, experience the sensation of shortness of breath and running out of air during speech. In addition, glottal closure is required for individuals to create positive end expiratory pressure (PEEP). Thus, some patients with an immediate postoperative unilateral vocal fold paralysis (UVFP) can experience decreased pulmonary function because of loss of the natural PEEP that occurs with glottal closure. The glottic closure that allows a forceful cough is also compromised and thus a weak, unsuccessful cough is often reported by patients.

Indications

The indications for treatment of unilateral vocal fold paralysis (UVFP) are usually the resultant dysphonia or an ineffective cough in a patient at risk for aspiration or pulmonary compromise. Treatment may be more imperative if severe dysphagia is present. If patients experience dysphagia, then they are at risk for aspiration pneumonia and treatment should be implemented immediately.

For dysphonia related to unilateral vocal fold paralysis (UVFP), treatment should be determined based on the patient's functional needs and demands. Some patients do not notice any significant functional limitation related to their unilateral vocal fold paralysis (UVFP). This minimal functional limitation results because of the person's minimal voice demands or comorbidities that occur during postoperative recovery. A temporary injection is often given to allow for an immediate return of glottic competence while the nerve potentially recovers. Electromyelography (EMG) can be used to determine the prognosis of RLN recovery, even if a temporary injection has occurred. If motion does not return and serial laryngeal electromyography shows no chance for meaningful recovery of vocal fold motion, then a permanent injection of fat, a semipermanent injection of calcium hydroxylapatite, or a medialization laryngoplasty can be offered.

In addition to patient history regarding functional aspects of voice use and voice demands, a standardized voice-related outcome measure can be used to assess the patient's vocal limitations and disability. The voice handicap index has been shown to be a reliable and useful patient-based survey instrument, quantifying the patient's voice handicap due to their voice disorder.

Note that the indications for treatment are related to the patient's function and limitations. Nonsurgical treatment can be offered to patients with unilateral vocal fold paralysis (UVFP), especially those who are unwilling or unable to proceed with surgical treatment.

Relevant Anatomy

The anatomy of the vagus/recurrent laryngeal nerve has been outlined above (see Pathophysiology), and its understanding is crucial to the evaluation of the potential etiology for patients who present with unilateral vocal fold paralysis (UVFP).

An understanding of both the internal and external laryngeal anatomy is important for the surgical treatment of unilateral vocal fold paralysis (UVFP). For patients who receive a vocal fold injection, an appreciation and thorough understanding of the anatomy of the membranous vocal fold, vocal process of the arytenoid cartilage, and paraglottic space is crucial for successful treatment.

Laryngeal framework surgery for the treatment of unilateral vocal fold paralysis (UVFP) requires an understanding of the relationship and anatomy of the thyroid cartilage and cricoid cartilage. This is especially true regarding the relationship of the membranous vocal fold and paraglottic space to the external landmarks of the thyroid cartilage. For the more advanced laryngeal framework surgery techniques (eg, arytenoid adduction, cricothyroid subluxation), thorough knowledge of the anatomy of the cricothyroid joint and cricoarytenoid joint are required to be successful.

Contraindications

No contraindications exist for the nonsurgical treatment of unilateral vocal fold paralysis (UVFP) other than the patient not indicating or realizing the need for treatment. Contraindications for the surgical treatment of unilateral vocal fold paralysis (UVFP) can include medical problems, such as severe cardiac or pulmonary limitations, or anticoagulation therapy. Although more risky and not ideal, injection of an anticoagulated patient has been routinely performed successfully in our practice. Performing injections on a patient via a transoral or transcutaneous route under local or MAC anesthesia can also be done routinely in the riskier patient.  

A careful and detailed medical history and evaluation are required prior to deciding on surgical treatment for unilateral vocal fold paralysis (UVFP). Often, the most complete history is obtained in conjunction with an internal medicine physician and an anesthesiologist. A poorly abducting contralateral vocal fold is a relative contraindication for surgical treatment of unilateral vocal fold paralysis (UVFP) because of the airway reduction that occurs with surgical medialization of the paralyzed vocal fold.

Workup

Imaging Studies

• Although rarely obtained today for the workup of unilateral vocal fold paralysis (UVFP), chest radiography can be the first screening evaluation for a patient with unilateral vocal fold paralysis (UVFP) of unknown etiology. This may reveal a chest malignancy as the cause of the unilateral vocal fold paralysis (UVFP). A Pancoast tumor, mediastinal mass, or even massive cardiomegaly may be found. The latter has rarely been shown to be a cause of unilateral vocal fold paralysis (UVFP) when enlargement of the left atrium that causes a stretch injury to the left recurrent laryngeal nerve is present.
• CT scanning or MRI of the path of the vagus/recurrent laryngeal nerve  
  • CT scanning or MRI should be performed as part of a workup for a unilateral vocal fold paralysis (UVFP) of unknown etiology. The imaging should include the entire path of the vagus/recurrent laryngeal nerve involved. A left unilateral vocal fold paralysis (UVFP) involves imaging from the base of skull to the mid chest (arch of the aorta). The right unilateral vocal fold paralysis (UVFP) evaluation should extend from the base of the skull to the clavicle.
  • Although CT is usually the test of choice, the decision between CT scanning and MRI is personal and can be decided by the otolaryngologist and radiologist.

Other Tests

• Voice evaluation: Voice evaluation by a speech-language pathologist is often helpful to determine the degree of maladaptive compensatory behavior present. In addition, voice recording provides documentation of the baseline voice quality and ability. This is important because treatment for the vocal fold paralysis usually begins shortly after evaluation. Often, this voice evaluation includes an objective analysis of the voice quality of the patient, including acoustic and aerodynamic analysis (air flow and laryngeal efficiency) of speech production.
• Laryngeal electromyography (LEMG)
  • LEMG is an electrophysiologic evaluation of the muscles of the larynx. This test is performed using an EMG needle percutaneously under local or no anesthesia. The LEMG most often involves an evaluation of the thyroarytenoid/lateral cricoarytenoid muscle complex, which is reflective of the recurrent laryngeal nerve innervation and the cricothyroid muscle, which is indicative of the superior laryngeal nerve status/function.
  • LEMG findings can be diagnostic and prognostic and can therefore be a useful tool to guide therapy. LEMG can be used to differentiate between vocal fold immobility caused by cricoarytenoid joint pathology and that caused by vocal fold paralysis. The timing of LEMG is crucial in accurately determining the prognosis of spontaneous recovery of the paralyzed vocal fold. LEMG is most predictive of outcome if performed 6 weeks to 6 months after the onset of symptoms. LEMG can shorten the time until permanent treatment is implemented, subsequently reducing the time of the patient's dysphonia and the number of temporary treatments required.

Treatment

Medical Therapy

• Medical therapy: Medical therapy plays a very small role in the treatment of patients with unilateral vocal fold paralysis (UVFP). When concomitant gastroesophageal reflux disease and/or sinonasal allergic disease are present, medical therapy for these disorders is indicated.
• Voice therapy
  • Voice therapy can play a role in the treatment of unilateral vocal fold paralysis (UVFP). Voice therapy can be used as sole treatment or as part of combined treatment with surgical medialization of the paralyzed vocal fold. Voice therapy is the primary treatment in patients who have a favorable (ie, median) position of their vocal fold paralysis and fairly equal tonicity between vocal folds or those who are unwilling or unable to undergo surgery because of psychological or medical limitations.
  • In the setting of vocal fold paralysis, voice therapy is generally not a long-term treatment modality; substantive results are usually obtained in 2-3 sessions. Postoperative voice therapy used in combination with surgery is often used; however, 1-2 sessions of voice therapy prior to surgical treatment of unilateral vocal fold paralysis (UVFP) can often be efficacious. This type of preoperative voice therapy focuses on vocal hygiene and establishes the principles of voice therapy that will be solidified during the postoperative period.
  • The most commonly used voice therapy techniques for unilateral vocal fold paralysis (UVFP) include vocal hygiene and modification of voice use and the voice use environment. In addition, direct voice therapy techniques (eg, flow phonation, resonant voice and proper use of the respiratory support for phonation, phrase, and word timing) are often used. Preoperative voice therapy can decrease the secondary muscle tension dysphonia (MTD), while postoperative voice therapy can improve muscle strength, agility, and coordination.

Surgical Therapy

Multiple surgeries are available for the treatment of unilateral vocal fold paralysis (UVFP), and they can be broadly categorized into temporary and permanent procedures. Temporary treatment involves endoscopic injection of a resorbable material into the affected vocal fold, lateral to the thyroarytenoid muscle in the paraglottic space. The resultant medialization of the paralyzed vocal fold improves vocal quality by restoring glottal competence and may improve swallowing function. Temporary vocal fold injection can be used when return of recurrent laryngeal nerve function is expected or when the prognosis for recovery is unknown during the first 6 months after onset of paralysis (especially when a favorable prognosis is found on LEMG).

Many temporary injection materials are available. Radiesse voice gel is composed of water, glycerin, and sodium carboxymethylcellulose (an organic polymer used as a carrier in other injectable pharmaceutical products and an additive in gelatinous foods). Radiesse voice gel effectively medializes the paralyzed vocal fold for 1-3 months and does not require extra time to harvest, prepare, or reconstitute, which is common with other injectable materials.¹

Hyaluronic acid is a polysaccharide ubiquitous in the extracellular matrix of most species and, therefore, is nonimmunogenic. Widely used as a filler by facial plastic surgeons, hyaluronic acid also can be used as a temporary injection material to medialize the paralyzed vocal fold, although it has a limited track record in laryngology.

Cymetra, a freeze-dried micronized acellular human cadaveric dermis, can also be used to augment the paralyzed vocal fold for 1-3 months. It has the slight disadvantage of requiring extra time for reconstituting and preparing the material for injection. Because this material is derived from humans, infectious disease is a risk, although insignificant.

Gelfoam is a bovine gelatin agent with a long history of safety, efficacy, and predictability, and, therefore, remains the most common injectable material today. Nevertheless, its disadvantages, such as a large (18 gauge) needle requirement and a short duration of effect (4-6 weeks), have prompted a shift toward newer, longer-lasting materials.

Cross-linked bovine collagen (Zyplast/Zyderm) is another effective injection material. The primary drawback is the need for allergy skin testing before use (14 days).

Permanent vocal fold surgical treatment can be divided into vocal fold injection and laryngeal framework surgery. Injection technique is similar to that with temporary materials: however, more permanent substances such as fat, fascia, or the semipermanent calcium hydroxylapatite (CaHA) are used.

Autologous fat is typically harvested from the patient's abdomen with liposuction technique. Variability in resorption somewhat limits the predictability of long-term voice outcomes and repeat lipoinjection may be necessary to achieve the desired results.

CaHA consists of calcium phosphorus in the form of microspheres in a gel carrier. The gel carrier resorbs, so slight overinjection (10-15%) is necessary; however, the microspheres have shown resorption over approximately 2 years since it has been used clinically.

Teflon is acceptable only in patients with unilateral vocal fold paralysis (UVFP) due to a terminal disease because of the significant long-term complication rate of Teflon granuloma formation. The incidence of Teflon granuloma formation is estimated to be over 50% with long-term follow-up, and the treatment of this complication usually requires surgery (often several) and permanent diminution in vocal function.  With other options available, Teflon is rarely used today.

Both temporary and permanent vocal fold injections are performed more frequently in an office-based outpatient setting. Newer injection materials with fine-gauge needles and chip-tip flexible endoscopes have facilitated this transition from the operating room to the office. The patient is seated in the sniffing position and the airway is topically anesthetized. Under endoscopic guidance, the paralyzed vocal fold can be injected via peroral or transcutaneous (thyrohyoid, transthyroid, or cricothyroid) routes. Advantages of office-based injections include patient convenience, cost savings, real-time monitoring of voice quality, and avoidance of general anesthesia.

Despite the increasing popularity and availability of permanent injection materials, laryngeal framework surgery remains the criterion standard for long-term treatment of unilateral vocal fold paralysis (UVFP). Isshiki reintroduced laryngeal framework surgery for the treatment of unilateral vocal fold paralysis (UVFP) to the world in 1974 when he described a type I thyroplasty. This was a concept that Payr initially described. The concept of medialization laryngoplasty is to medialize the paralyzed vocal fold from an external approach and work through the thyroid cartilage. A small window is incised and removed from the thyroid cartilage, and an implant is placed through the window to medialize the paralyzed vocal fold.

The most common implant used is a silastic block that is either sized from a variety of prefabricated implants or custom carved to address the 3-dimensional nature of the patient's unilateral vocal fold paralysis (UVFP). Gore-Tex is another thyroplasty implant option and has been long regarded as a safe, well-tolerated implant in other parts of the body. Gore-Tex has dramatically increased in popularity in recent years because of its ability to be finely adjusted easily during surgery.

This operation has recently been widely accepted, and from a conceptual perspective, appears quite simple. A national survey found that complication rates with this procedure are higher in surgeons with inexperience or infrequent use of this operation. This most likely is related to the complex 3-dimensional anatomy of the vocal fold, paraglottic space, and implant design. Note that the implant design using medialization laryngoplasty must simultaneously address the treatment of the paralyzed vocal fold in the medial-lateral, superior-inferior, and anterior-posterior dimensions. Optimal voice results from medialization laryngoplasty involve appropriate consideration and treatment of the paralyzed vocal fold in all 3 of these dimensions with the implanted material.

More advanced and recent techniques for surgical treatment of unilateral vocal fold paralysis (UVFP) using laryngeal framework surgery have involved manipulation of the arytenoid cartilage, namely arytenoid adduction. Isshiki also pioneered arytenoid adduction, an operation that places the arytenoid cartilage in the most favorable position for rehabilitation of the paralyzed vocal fold. Isshiki described placing a suture through the muscular process of the arytenoid cartilage and drawing the suture anteriorly into the larynx (arytenoid adduction). Woodson and Zeitels have recently proposed modifications to the Isshiki procedure to enhance the arytenoid repositioning. The former suggests the placement of a second suture on the muscular process of the arytenoid and securing it to the lateral-inferior aspect of the cricoid to simulate the pull of the vertical belly of the posterior cricoarytenoid muscle.

Surgical treatment of the arytenoid cartilage for unilateral vocal fold paralysis (UVFP) is important to restore optimal length/tension of the paralyzed vocal fold and to medialize the posterior glottis. The latter has become an indication for patients with severe dysphagia, especially those patients who have been identified to have aspiration pneumonia due to incompetence of the posterior glottis.

These operations are more technically challenging than a medialization laryngoplasty and are not required for every patient with unilateral vocal fold paralysis (UVFP); however, combined surgical treatment of unilateral vocal fold paralysis (UVFP) with both an adduction procedure involving the arytenoid cartilage and medialization laryngoplasty has been found to yield maximal vocal rehabilitation by many leading surgeons. This is a reasonable conclusion because medialization laryngoplasty addresses the position and bulk of the membranous vocal fold while operations on the arytenoid address tension and length of the paralyzed vocal fold. Addressing all of the distinct and important features of the paralyzed vocal fold yields the best surgical result for this condition.

In 1999, Zeitels described a new laryngeal framework procedure for unilateral vocal fold paralysis (UVFP) called cricothyroid subluxation.² This procedure involves anteriorly displacing the ipsilateral inferior cornu of the thyroid cartilage. This is performed by placement of a suture that runs from the inferior cornu of the thyroid cartilage to the midline of the cricoid cartilage. This effectively rotates the thyroid cartilage on the cricoid cartilage, providing additional length to the paralyzed vocal fold.

Preoperative Details

See use of LEMG in Other Tests for diagnosis and prognosis.

Intraoperative Details

During both in-office vocal fold injections and laryngeal framework surgery (thyroplasty and arytenoid adduction), voice is monitored. Voice quality is observed both perceptually and with laryngeal examination via flexible fiberoptic nasolaryngoscopy. This allows the surgeon to control or adjust the surgery to optimize the voice quality at the end of the procedure. This is an essential to high-quality phonosurgery and is the reason these procedures in general should not be conducted under general anesthesia. Today, vocal fold injections are commonly performed as office-based outpatient procedures with topical anesthesia.

Postoperative Details

After lipoinjection, patients are placed on voice rest to enhance the survival of the transplanted fat. This is typically for 5-7 days in duration. One or 2 days of voice rest are usually sufficient for other injectable materials, particularly those that use small (25- or 27-gauge) needles. No rest or minimal voice rest is necessary after laryngeal framework procedures.

Follow-up

A voice evaluation is indicated following surgical treatment of a unilateral vocal fold paralysis (UVFP). This evaluation should include a patient-based assessment of the voice function and head and neck examination, including indirect laryngoscopy and voice evaluation by a speech pathologist. The latter is important to assist in deciding whether the patient would be best served with postoperative voice therapy.

Complications

Complications of surgical treatment for unilateral vocal fold paralysis (UVFP) include poor voice outcome, airway difficulties, and migration of the medialization implant. Given that surgical treatment for unilateral vocal fold paralysis (UVFP) involves manipulation of the airway, factors such as swelling or a hematoma from either laryngeal framework surgery or vocal fold injection can cause airway difficulties. Prevention of this complication involves meticulous and precise surgical technique and the use of preoperative and postoperative steroids. A greater risk exists for airway compromise and difficulties when a bilateral procedure is performed, such as bilateral medialization laryngoplasty or bilateral vocal fold injection (for unilateral vocal fold paralysis [UVFP] or contralateral vocal fold atrophy).

Unless the surgery is performed strictly for dysphagia, most surgical procedures for unilateral vocal fold paralysis (UVFP) are elective in nature and are aimed at improving voice quality; if voice quality does not improve, this should be considered a complication of the procedure. Often, poor voice quality or the inability to improve the voice following laryngeal framework surgery can be rectified with revision medialization laryngoplasty, with or without an arytenoid adduction procedure.

The most common reason for poor voice quality following medialization laryngoplasty is improper placement of the thyroplasty implant in a too anterior and/or too superior direction. In addition, the implant size can be either too large or too small. Often, the implant is made too small because of a false sense of adequate medialization that occurs intraoperatively as a result of perioperative edema prior to implant placement of the thyroplasty implant. This can be prevented by the use of preoperative steroids, as well as expedient surgery, to minimize paraglottic edema prior to placement and sizing of the thyroplasty implant.

Thyroplasty implant migration can occur postoperatively, either medially into the airway or laterally into the neck. The former obviously is of great concern but appears to be rare. A single case report exists of complication of medialization laryngoplasty (silastic) caused by a delayed allergic response to the silastic implant.

Outcome and Prognosis

Expected voice outcome following the treatment for unilateral vocal fold paralysis (UVFP) is excellent. Most patients resume normal speaking activities and functions and are able to meet all normal voice demands. Singing is a higher demand than speaking and may not be restored to its premorbid condition. The ability to project one's voice over a large area in a loud manner is also often never fully restored despite optimal medical, behavioral, and surgical treatment. Most patients should have a normal or near-normal speaking voice ability with minimal to no functional limitations of their everyday voice use following successful treatment.

Future and Controversies

Understand that present surgical treatments only provide static improvement to the vocal fold and cannot provide the dynamic activity of the vocal fold to voice production that was present in the premorbid state. 

Thus, the future goal of laryngology research is to create a method of dynamic rehabilitation of the paralyzed vocal fold. This goal has been present for decades, and much work has been devoted to the concept of reinnervation of the vocal fold. In humans, the optimal result from reinnervation is a static vocal fold but one that has tone. Often, laryngeal reinnervation is performed simultaneously or sequentially with medialization laryngoplasty. The future of laryngeal reinnervation is unknown but serves as a vast area for research and progress.

Multimedia

Media file 1: Preoperatively, the arrow demonstrates the paralyzed vocal fold, which is characteristically foreshortened, lateralized, and flaccid.

Media file 2: Postoperatively, the image shows the same vocal fold from Image 1 following laryngeal framework surgery (arytenoids adduction and medialization laryngoplasty). The left vocal fold is now midline and has improved length.

Media file 3: Vocal fold paralysis, presurgery.

Video available at http://img.medscape.com/pi/emed/ckb/otolaryngology/834279-863537-863779-1565058.flv.

Media file 4: Vocal fold paralysis, postsurgery.

Video available at http://img.medscape.com/pi/emed/ckb/otolaryngology/834279-863537-863779-1565062.flv.

References

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Keywords

unilateral vocal fold paralysis, UVFP, vocal cord paralysis, neurogenic hoarseness, vocal cord paralysis, larynx, neurogenic hoarseness

Contributor Information and Disclosures

Author

Thomas L Carroll, MD, Assistant Professor, Department of Otolaryngology-Head and Neck Surgery, Tufts Medical Center, Tufts University School of Medicine
Thomas L Carroll, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Otolaryngology-Head and Neck Surgery, and American Medical Association
Disclosure: Nothing to disclose.

Coauthor(s)

Clark A Rosen, MD, Director, University of Pittsburgh Voice Center; Associate Professor, Department of Otolaryngology and Communication Science and Disorders, University of Pittsburgh School of Medicine
Clark A Rosen, MD is a member of the following medical societies: American Academy of Facial Plastic and Reconstructive Surgery, American Academy of Otolaryngology-Head and Neck Surgery, American College of Surgeons, American Medical Association, and Pennsylvania Medical Society
Disclosure: Bioform Medical  Consulting fee Consulting

Ryan J Soose, MD, Assistant Professor, Department of Otolaryngology, University of Pittsburgh Medical Center
Ryan J Soose, MD is a member of the following medical societies: Alpha Omega Alpha and Phi Beta Kappa
Disclosure: Nothing to disclose.

Medical Editor

John Schweinfurth, MD, Associate Professor, Department of Otolaryngology, University of Mississippi Medical Center
John Schweinfurth, MD is a member of the following medical societies: American Academy of Otolaryngic Allergy, American Academy of Otolaryngology-Head and Neck Surgery, and American Medical Association
Disclosure: Nothing to disclose.

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Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: eMedicine Salary Employment

Managing Editor

Robert M Kellman, MD, Professor and Chair, Department of Otolaryngology and Communication Sciences, State University of New York, Upstate Medical University
Robert M Kellman, MD is a member of the following medical societies: American Academy of Facial Plastic and Reconstructive Surgery, American Academy of Otolaryngology-Head and Neck Surgery, American College of Surgeons, American Medical Association, American Neurotology Society, American Rhinologic Society, American Society for Head and Neck Surgery, Medical Society of the State of New York, and Triological Society
Disclosure: GE Healthcare Honoraria Review panel membership

CME Editor

Christopher L Slack, MD, Otolaryngology-Facial Plastic Surgery, Private Practice, Associated Coastal ENT; Medical Director, Treasure Coast Sleep Disorders
Christopher L Slack, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Facial Plastic and Reconstructive Surgery, American Academy of Otolaryngology-Head and Neck Surgery, and American Medical Association
Disclosure: Nothing to disclose.

Chief Editor

Arlen D Meyers, MD, MBA, Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine
Arlen D Meyers, MD, MBA is a member of the following medical societies: American Academy of Facial Plastic and Reconstructive Surgery, American Academy of Otolaryngology-Head and Neck Surgery, and American Head and Neck Society
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