46 Unilateral and Bilateral Vocal Fold Paralysis



Carol Nhan, Jean-Paul Marie, Karen B. Zur


Summary


This chapter will describe the evaluation, management, and surgical procedures used by the senior authors for the management of unilateral vocal fold immobility (Section 46.1) and bilateral vocal fold immobility (Section 46.2), highlighting non-selective and selective laryngeal nerve reinnervations, respectively.




46 Unilateral and Bilateral Vocal Fold Paralysis



46.1 Part 1 Unilateral Vocal Fold Paralysis



46.1.1 Introduction


Unilateral vocal fold paralysis (UVFP) presents with dysphonia (weak, breathy or hoarse voice, stridor in infants) and sometimes aspiration. The primary surgical options are injection medialization and recurrent laryngeal nerve reinnervation (RLN). Due to chance of recovery and concern for a child’s developing laryngeal structures, the authors do not advocate for laryngeal framework procedures or arytenoid adduction, which carry risks of scarring or disruption of the laryngeal mechanism as well as prosthesis migration, airway obstruction and granulation formation.



46.1.2 Preoperative Evaluation




  • If there is no clear etiology to explain the vocal fold immobility (history of thoracic or neck surgery, cardiopulmonary disease, etc.), an MRI or CT scan from the brainstem to the carina should be obtained to determine whether there is a lesion along the vagus or RLN.



  • The symptoms and their severity will determine the treatment indicated.


    The clinical significance of the vocal fold paralysis is measured by:




    • The severity of the voice disorder as assessed by several acoustic and quality-of-life parameters including:




      • Pediatric voice handicap index (pVHI).



      • Maximal phonation time (MPT).



      • Grade-Roughness-Breathiness-Aesthenia-Strain evaluation (GBRAS) or Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V).



    • Aspiration on fiberoptic endoscopic evaluation of swallowing (FEES) or videofluoroscopic swallowing study (VFSS).



    • History of pneumonia.



    • Laryngoscopy or stroboscopy. Note the configuration of the vocal folds and arytenoids on laryngoscopy (example: injection medialization laryngoplasty is not as effective for a large posterior glottic gap).



    • In patients with comorbidities or a history of prematurity, other factors such as breath support may be contributory. It is important to set realistic expectations regarding therapy and surgical outcomes in these patients.



  • Formal swallowing assessment by a speech language pathologist (SLP).



  • Medical clearance for anesthesia.



  • Microlaryngoscopy and bronchoscopy with palpation of the cricoarytenoid joint to distinguish vocal fold paralysis/palsy from vocal fold fixation and to ensure there is no defect relating to intubation injury.



  • Laryngeal electromyography (LEMG) to confirm chronic denervation of the affected vocal fold.



46.1.3 Surgical Options


When conservative management (voice therapy or thickening of feeds for those who aspirate) fails, surgical options are considered.



46.1.4 Injection Medialization Laryngoplasty



Introduction

Injection medialization is a temporary measure to improve glottic insufficiency and thus treat dysphonia or aspiration in vocal fold immobility. It is a good option even when there is a possibility for recovery of vocal fold function.



Preoperative Evaluation and Anesthesia



  • See section 46.1.2 preoperative evaluation.



  • Discussion regarding injection as a temporary treatment, and consideration of possible materials and their duration of effectiveness (short-term 2–3 months vs. long-term 1–2 years). Disclosure that injection material use in children is “off-label” use of an FDA-approved (United States Food and Drug Administration) procedure in adults.



  • Injection medialization may be of limited effectiveness when the problem is caused by a large posterior glottic gap.



  • Short-term injection with gel-type material often provides better voice outcomes and better plumping of the vocal fold in children compared to the longer-term more viscous injectates.



  • Spontaneous ventilation without endotracheal tube by anesthesia is recommended. Insufflation via an endotracheal tube placed in the hypopharynx may be helpful.



Surgical Technique



  • Vocal fold mobility is assessed before deepening anesthesia.



  • Suspension microlaryngoscopy or suspension with visualization of a telescope rod is used. Palpation to rule out cricoarytenoid fixation and other lesions causing immobility is performed.



  • The injection material is prepared and the needle primed. Some materials come pre-packaged with a long transoral needle. Otherwise, bruning syringe or a 25-gauge butterfly needle with cut flanges and grasped with a cupped or alligator forceps may be used.



  • Injection is performed anterior and lateral to the involved vocal process (▶ Fig. 46.1a). This is best done by using the side of the needle to slightly lateralize the false vocal fold on the affected side, aiming to inject lateral to the thyroarytenoid muscle (▶ Fig. 46.2). Make sure that the needle is not too deep that the material extrudes intraluminally on the undersurface of the vocal fold or too superficial such that it goes into the lamina propria causing a poor voice outcome by disrupting the mucosal wave. With gentle continuous pressure on the syringe plunger, plumping of the vocal fold and reduction of the glottis gap is achieved (▶ Fig. 46.1b and ▶ Video 46.1).

Fig. 46.1 (a) Insertion of transoral needle for an injection laryngoplasty. (b) Mild plumping noted after the injection is complete. Mild posterior subglottic stenosis is noted as well in this patient.
Fig. 46.2 Schematic representation of the placement of an injection material immediately lateral to the vocal fold, allowing medial displacement and plumping of the vocal fold to reduce a glottic gap. (Reproduced from Potsic, Cotton, Handler, and Zur. Surgical Pediatric Otolaryngology. 2nd ed. ©2016, Thieme Publishers, New York. Illustration by Susan Shapiro Brenman/Birck Cox/Eo Trueblood.)


Postoperative Treatment



  • No postoperative restrictions are necessary.



  • The family should be advised that the voice may be strained in the first 2 weeks.



46.1.5 Highlights




  1. Indications




    • Dysphonia or aspiration secondary to vocal fold immobility or paralysis with glottic insufficiency.



  2. Contraindications




    • Medical contraindication to general anesthesia.



  3. Complications




    • Inadequate or no improvement in dysphonia/dysphagia; foreign body reaction with certain injection materials; low risk of over-injection and airway compromise in infants.



  4. Special intraoperative considerations




    • Spontaneous ventilation with insufflation, deepened plane to anesthesia to prevent laryngospasm. While unlikely to impact laryngeal EMG (electromyography) recordings, the author does not routinely use 2% lidocaine topical spray for patients undergoing an EMG.



46.1.6 Unilateral Ansa Cervicalis to Recurrent Laryngeal Nerve Reinnervation



Introduction

Unilateral recurrent laryngeal nerve reinnervation allows for improving posterior glottic closure at the interarytenoid level and maintaining increased tone of the paralyzed vocal fold to improve voice and to manage aspiration. Most commonly, one of the ansa cervicalis nerve roots is used to anastomose and innervate the affected recurrent laryngeal nerve. Since this procedure requires transection of the recurrent laryngeal nerve (RLN), it is imperative that irreversible damage to the nerve is ascertained before proceeding. This is confirmed with an intraoperative laryngeal EMG (electromyography). Often, patients have already undergone an injection medialization laryngoplasty to confirm its effectiveness before deciding to undergo a more definitive surgery such as a unilateral recurrent laryngeal nerve reinnervation.



Preoperative Evaluation and Anesthesia



  • See above section 46.1.2 preoperative evaluation.



  • A laryngeal electromyography (LEMG) is obtained intraoperatively to confirm paralysis.



  • This procedure is generally performed in conjunction with a temporary vocal fold injection medializaton to allow for immediate improvement while reinnervation takes effect.



  • No paralysis to allow nerve stimulation.



Surgical Technique



  • A shoulder roll is placed and the head turned to the opposite side. Standard prepping and draping is performed.



  • Mark the point along the sternocleidomastoid (SCM) where the omohyoid muscle crosses the carotid sheath. This is the midpoint of your curvilinear incision (approx. 3 cm). Subplastysmal flaps are elevated.



  • The anterior border of the SCM is dissected to allow posterior retraction and the omohyoid muscle is dissected where it crosses under the SCM and is retracted medially and inferiorly (▶ Fig. 46.3).



  • The ansa cervicalis can be found overlying the internal jugular vein (IJV). Its inferior loop and its branches (to omohyoid, sternohyoid, and sternothyroid) are located (▶ Fig. 46.4a, b and ▶ Video 46.2). A nerve stimulator may be used to confirm the integrity of the ansa cervicalis donor nerve roots.



  • Next, the RLN is identified in the tracheoesophageal groove by elevating the straps from the thyroid gland (from a lateral approach), and dissecting caudal to the inferior pole of the ipsilateral thyroid lobe (▶ Fig. 46.5 and ▶ Video 46.3). In cases where the nerve is not easily found, you may need to identify it at its insertion into larynx by the cricothyroid joint after reflecting the superior thyroid pole inferiorly and medially and performing retrograde dissection to achieve a nerve segment that is 1 to 2 cm to ensure tension-free anastomosis. Care should be taken to avoid injury to the parathyroid glands.



  • A tunnel is created under the strap muscles to allow anastomosis between the ansa cervicalis and RLN (▶ Fig. 46.6 and ▶ Video 46.4). A ¼-inch penrose may be used to retract the straps medially so that the anastomosis can be performed with good exposure of both nerves.



  • A sterile-draped microscope and microinstruments are used to perform the anastomosis (▶ Fig. 46.7 a, b and ▶ Video 46.5).



  • Determine which ansa cervicalis branch has the best caliber match to the RLN, verifying that it can be mobilized to create a tension-free anastomosis. Transect it distally.



  • Transect the RLN with a 1- to 2-cm stump to allow rotation toward the lateral neck.



  • The author tags both nerves with a micro-ligature clip so that the nerve does not retract, making it difficult to find. Once ready for the actual microneurography, the ligature is cut and the nerve edge freshened.



  • Use a BV 100–4, 9–0 monofilament nylon suture to approximate the epineuria of the proximal ansa cervicalis nerve end to the distal RLN nerve end. Depending on the nerve caliber, one suture or two sutures placed at two points approximately 180 degrees apart can be used. Tissue glue may be placed around the anastomosis.



  • Remove the penrose drain retractor and lay the strap muscles back over the anastomosis.



  • The straps, platysma and skin are closed. No drain is needed.

Fig. 46.3 Surgical exposure of the anterior border of the sternocleidomastoid (SCM) muscle and the omohyoid muscle. (Reproduced from Potsic, Cotton, Handler, and Zur. Surgical Pediatric Otolaryngology. 2nd ed. ©2016, Thieme Publishers, New York. Illustration by Susan Shapiro Brenman/Birck Cox/Eo Trueblood.)
Fig. 46.4 (a) Schematic representation of the ansa cervicalis branches and the tunnel created by dissection of the strap muscles. (Reproduced from Potsic, Cotton, Handler, and Zur. Surgical Pediatric Otolaryngology. 2nd ed. ©2016, Thieme Publishers, New York. Illustration by Susan Shapiro Brenman/Birck Cox/Eo Trueblood.) (b) Surgical exposure of the ansa cervicalis branches, and retraction of the strap muscles using a penrose drain.
Fig. 46.5 Schematic representation of the exposure of the recurrent laryngeal nerve after retraction of the strap muscles off of the inferior thyroid gland. (Reproduced from Potsic, Cotton, Handler, and Zur. Surgical Pediatric Otolaryngology. 2nd ed. ©2016, Thieme Publishers, New York. Illustration by Susan Shapiro Brenman/Birck Cox/Eo Trueblood.)
Fig. 46.6 Schematic representation of the arc of rotation of the cut donor ansa cervicalis branch and the cut recurrent laryngeal nerve. (Reproduced from Potsic, Cotton, Handler, and Zur. Surgical Pediatric Otolaryngology. 2nd ed. ©2016, Thieme Publishers, New York. Illustration by Susan Shapiro Brenman/Birck Cox/Eo Trueblood.)
Fig. 46.7 (a) Schematic representation of the anastomosis of the recurrent laryngeal nerve and ansa cervicalis. (Reproduced from Potsic, Cotton, Handler, and Zur. Surgical Pediatric Otolaryngology. 2nd ed. ©2016, Thieme Publishers, New York. Illustration by Susan Shapiro Brenman/Birck Cox/Eo Trueblood.) (b) Surgical depiction of the anastomosis. Arrow end shows the recurrent laryngeal nerve, the arrow shows the ansa cervicalis branch.

Only gold members can continue reading. Log In or Register to continue

Feb 8, 2021 | Posted by in HEAD AND NECK SURGERY | Comments Off on 46 Unilateral and Bilateral Vocal Fold Paralysis
Premium Wordpress Themes by UFO Themes