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Innovative technique for lingual tonsillectomy and midline posterior glossectomy for obstructive sleep apnea
Operative Techniques in Otolaryngology (2007) 18, 20-28
Innovative technique for lingual tonsillectomy and midline posterior glossectomy for obstructive sleep apnea B. Tucker Woodson, MD, FACS From the Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin. KEYWORDS Obstructive sleep apnea; Surgery; Lingual tonsil; Tongue; Glossectomy; Local anesthesia; Low morbidity; Endoscope; Plasma; Coblation
Hypopharyngeal airway obstruction may result from abnormal or disproportionate tongue base anatomy or lingual tonsil hypertrophy. Partial glossectomy and lingual tonsillectomy may be difficult and excessively morbid procedures in the sleep apnea population. Techniques are described using plasma surgery tools, combined with endoscopy, that allow for improved visualization and more complete removal of lingual tonsils and low morbidity mucosal sparing excisional glossectomy. © 2007 Elsevier Inc. All rights reserved.
Obstructive sleep apnea syndrome (OSAS) results from a complex scenario initiated with a structurally small upper airway followed by airway collapse and obstruction, loss of compensatory wake and sleep reflexes, increased ventilatory effort, arousal, hypoventilation, and asphyxia during sleep. The etiology of the small upper airway in adults may include an abnormal craniofacial structure, excessive soft tissue for the available space, and obesity. Enlarging or removing the obstruction from the airway may prevent the cascade into sleep apnea and snoring. Multiple structural abnormalities contribute to airway obstruction. Otolaryngologists historically have used uvulopalatopharyngoplasty (UPPP) to treat patients with OSAS, but this treatment fails to address other airway abnormalities that are not limited to the upper pharynx. Both primary and secondary sites of obstruction occur in the lower airway.1 Hypopharyngeal obstruction may involve the tongue base, lateral hypopharynygeal walls, lingual tonAddress reprint requests and correspondence: B. Tucker Woodson, MD, FACS, Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, 9200 W. Wisconsin Avenue, Milwaukee, WI 53226. E-mail address: [email protected]. 1043-1810/$ -see front matter © 2007 Elsevier Inc. All rights reserved. doi:10.1016/j.otot.2007.03.004
sils, and supraglottic larynx. The use of multiple procedures to treat these sites have met with varying effectiveness and morbidity. In this work, 2 innovative procedures to treat the lower pharynx, lingual tonsillectomy and transoral submucosal endoscopic assisted glossectomy, are described. Both have the advantage of lower patient morbidity compared with previously described techniques.
Lingual tonsillectomy Hypertrophic lingual tonsils may partially or completely obstruct the retrolingual airway. Removing these tissues enlarges the airway and improves breathing, swallowing, and sleeping. Although conceptually straightforward, removing lingual tonsils may be difficult, particularly in the sleep apnea patient who exhibits mandibular and maxillary hypoplasia and or macroglossia. Transoral exposure and access are difficult. Additionally, patients with OSAS are at greater risk of airway complications resulting from the use of anesthesia. Traditional methods have included cautery, cryotherapy, and laser, among others. Laser by means of the carbon dioxide or KTP-Yag lasers commonly have been
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used. This method, however, restricts visualization to a straight line and the exposure is worsened by even small amounts of bleeding and char. Because of the difficulty in adequately performing the procedure, the author’s experience was to limit lingual tonsillectomy only to the more severe cases of lingual tonsil hypertrophy. Recently, a new tool and improved methods of visualization have reduced these difficulties.2 This new technique uses a bipolar radiofrequency plasma surgery tool called “coblation” (Arthrocare Corp, ENTec division, Sunnyvale, CA). This device creates a low-temperature plasma field. The corona of activated ions disassociates tissues, which are removed in a saline irrigation field. Removal of lymphoid tissue and muscle is relatively bloodless and without char. This tool minimizes tissue trauma, intraoperative bleeding, char formation, and postoperative pain. Its ease of use, malleable probe, and ability to work outside the lumen of the laryngoscope and with rigid fiberoptic scopes allows removal of tissue that would typically be extremely difficult using laser or other techniques.
Lingual tonsillectomy evaluation Evaluation routinely includes flexible nasopharyngoscopy/laryngoscopy. Candidates who will likely benefit have a bulk of lingual tonsils that obscure visualization of the root of the epiglottis/valleculae on supine awake examination. In some cases, a magnetic resonance scan (MRI) can discriminate muscle, fat, and lymphoid tissue and define the actual volume of hypertrophic tonsils (Figure 1). Before surgery, medical treatment of lingual tonsil hypertrophy may include addressing infection, allergy, and gastroesphageal reflux disease. Limited data exist on the effectiveness of these medical therapies. Risks of neoplastic disease in the adult warrant further evaluation, especially with recent changes in size or symptoms or if other lymphadenopathy exists.
Lingual tonsillectomy method The procedure is performed with the patient under general nasotracheal anesthesia. Nasotracheal intubation allows displacement of the endotracheal tube away from the base of the tongue. Exposure of the valleculae in the OSAS patient usually requires a suspension rigid laryngoscope (such as a Weerda bi-valved laryngoscope). Tissue is removed using a plasma surgery device (Evac 70 tonsil and adenoid coblation wand) with a coblator II generator (setting 7-9, Arthrocare Corp, ENTec division). Optimum dissection can be obtained by bending the malleable wand approximately 30° and inserting the probe between the corner of the mouth and outside of the laryngoscope, with the tip of the probe being visualized in the operative field beyond the tip of the laryngoscope (Figure 2). Counter pressure over the hyoid region may further augment exposure. After removal of the bulk of lingual tonsils, a 70° angled telescope may allow better inspection of the hypopharynx and precise removal of additional tissue. In selected cases, it markedly improves visualization after lingual tonsils have
Figure 1 Midsagittal (A) and coronal (B) magnetic resonance imaging demonstrating enlarged lingual tonsils filling the vallecular space and tipping the epiglottis posteriorly and contrast-enhanced axial magnetic resonance imaging depicting highlighted region of lingual tonsils obstructing the airway.
been debulked. Steps of this method include a bite block to open the mouth, a lower tooth guard to protect the ventral surface of the tongue, a posteriorly placed traction suture on the dorsum of the tongue, and vigorous traction on the tongue. Using an irrigation system further improves visualization of the valleculae, hypopharynx, and larynx. The angled scope may identify lingual tonsil tissue lateral to the midline that has often been difficult to identify and safely remove. In some adults (in contrast to experience in children), the anatomy does not allow visualization using rigid telescopes without the concomitant use of a rigid scope and
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Operative Techniques in Otolaryngology, Vol 18, No 1, March 2007 (average of 3) on a visual analog scale from 0 to 10. No primary bleeding has occurred, and secondary bleeding has been less than 5%. Blood loss during the procedures is minimal and has ranged from approximately 0 mL to 50 mL, with an average of 20 mL. Patients do not require tracheostomy tube placement under normal conditions. No significant airway edema of the hypopharynx or larynx has been observed postoperatively. Even in cases of mild mucosal injury to the epiglottis by the plasma wand, edema has been mild. Risks of the procedure include airway obstruction, bleeding, dysphagia, change in taste, and persistence of sleep disordered breathing. Before the combined use of the angled 70° fiberoptic scope, residual lateral lymphoid tissue was not uncommon and is less with the improved exposure provided by the scope.
Discussion
Figure 2 Placement of the coblation wand (A) to the side of the laryngoscope (B) leaves the lumen unobstructed and allows better visualization and easier dissection of the lingual tonsils and base of tongue region.
a rigid scope combined with an endoscope or the operating microscope may be needed. Other technical points also can help. Irrigation is improved using a pressure bag applied to the irrigation bag to deliver a continuous stream of fluid onto the operative field against gravity (especially when the tip of the probe is directed upward). Dissection is initiated at the base of the valleculae, and the laryngoscope is slowly withdrawn until the foramen cecum is identified. This is the anterior midline limit of dissection. The device hemostatically excises lymphoid tissue; bleeding vessels may indicate muscle and can be controlled using the device coagulation mode. Major bleeding vessels may suggest a deeper dissection beyond the tonsil bed or beyond the intended surgical field into the supraglottis. Suction electrocautery also may be used. In some individuals with OSA even the most experienced endoscopist cannot expose the surgical field. In these cases, exposure may be achieved by a midline posterior glossectomy. Recuperation has been similar between individuals undergoing lingual tonsillectomy alone and combined with partial glossectomy. Lingual tonsillectomy using this method has been used for both modest and massive hypertrophy. Operative time varies from 10 to 30 minutes for modest hypertrophy to several hours with massive hypertrophy. Care should be taken in prolonged cases to intermittently release compression on the tongue; this is done at least once every hour. Immediately after the procedure, patient pain appears to be mild to moderate, with pain scores ranging from 0 to 7
A variety of techniques have been described in the literature for lingual tonsillectomy, including sharp dissection, laser, suction diathermy, cryotherapy, and the use of an ultrasonic coagulating dissector.3-6 The use of laser techniques carry a small risk of airway fire and require more equipment, setup, and specialized endotracheal tubes. In addition, dissection is slower compared with the coblation technique. Suction diathermy chars tissue, and cryotherapy yields unpredictable results. Traditionally, lingual tonsil removal has been extremely difficult. Classical approaches using a tonsillectomy gag do not expose the valleculae in sleep apnea patients. Laryngoscopic visualization allows exposure, but the procedure is difficult. The current technique with a malleable curved instrument is more versatile and allows for precise and rapid removal. The lack of char, excellent hemostasis, minimal thermal trauma and edema, and lower pain levels reduce morbidity of the procedure and expand the potential indications for lingual tonsillectomy.
Transoral submucosal endoscopic-assisted glossectomy Glossectomy treats lower pharyngeal by modifying the shape and size of the soft tissue tongue base, hypopharynx, and supraglottic tissues.7-9 Airway space is increased by reducing the bulk of soft tissue. Although conceptually simple, using traditional methods, morbidity of the procedure may be high and exposure difficult. Risks of airway obstruction, bleeding, infection, and dysphagia have been reported as many as 25% of patients. Glossectomy morbidity and complications have been associated with the aggressiveness of resection and the nature of the surgical tools used. The more tissue was removed or damaged, the worse the perioperative recovery (pain, edema, dysphagia, bleeding, infection). The relatively high rate of morbidity has restricted the procedure to a limited population of patients who were not candidates for other therapies or procedures. Alternatively, radiofrequency tissue ablation has been used to reduce tongue volume.10,11 The rate of patient morbidity when this tool is used is lower, and evidence-based medi-
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Figure 3 Moore Tongue base classification is depicted. Assessment is performed endoscopically with subjective rating of hypopharyngeal obstruction pattern. Three general patterns are described based on the levels (low tongue base, proximal tongue base, combined) of perceived narrowing and obstruction. Type A describes isolated upper tongue base obstruction. A common etiology for this is lingual tonsil hypertrophy. Type C describes lower tongue base obstruction (retro-hyoid/retro-epiglottic). Type B is combined.
cine shows a definite clinical effect. The therapy requires multiple sessions, and volume reduction often is inadequate to result in the desired clinical outcome. An alternative excisional procedure that preserves mucosa and with less morbidity than conventional glossectomy has been described.12 Postoperative seroma and untreated wound deadspace caused persistent swelling. Concerns about these risks, as well as infection, nerve, and vessel injury, prompted the development of the current method. The innovative technique described differs from previous techniques in allowing graded tissue excision (single or staged), preservation of tongue mucosa and taste buds, reduced tissue trauma pain and edema, and low complication rates. The procedure is performed under local or general anesthesia. Glossectomy removing significant bulk of the posterior tongue can be performed under local anesthesia and assisted with sedation. Excision is performed transorally via a midline incision. Tissue is removed submucosally, with the surgeon taking care to preserve taste buds and minimizing pain. The use of ultrasound identifies the lingual vessels as anatomic landmarks to avoid damage to important structures. Exposure to the midline tongue muscles is obtained with 3 traction sutures. A plasma knife excises tissue progressively posteriorly and laterally. Disintegrated tissue is removed by a continuous flow of saline. Surgery is performed using endoscopic visualization. Patients may resume an oral diet rapidly after the procedure.
Glossectomy evaluation Hypopharyngeal airway obstruction due to relative macroglossia is the primary indications for glossectomy. Structural assessment of obstructive tongue base anatomy may be performed using several methods, including a modified Malampatti 3 or 4, Fujita Type II or type III, and Moore Class A and B. All describe soft-tissue abnormalities to the tongue base. The Moore classification defines abnormal
hypopharyngeal anatomy into 3 basic types, that is, A, B, and C (Figure 3). Type A demonstrates high tongue base obstruction, type B demonstrates obstruction in both the high and low tongue base and retro-epiglottic obstruction, and type C demonstrates retro-epiglottic obstruction alone. Because the current procedure demonstrates lower morbidity and patient acceptance (and is more similar to ablational radiofrequency), the population that are potential candidates is broader in contrast to procedures that result in greater morbidity, which are most appropriately applied in patients who suffer severe disease and in whom alternative procedures are not appropriate. Contraindications to glossectomy (for the treatment of sleep apnea) may include patients with swallowing or speech problems or with a lingual thyroid. Previous techniques of glossectomy may affect the circumvallate papillae and taste buds to a greater degree, and minor (and often transient) changes in taste have been observed. However, in certain professions and individuals, even minor changes in taste would cause potential disability. The current technique attempts to preserve mucosa and taste buds and has not been observed to alter taste. Patients with poor pulmonary reserve (who would be at severe risk if swallowing difficulties developed), patients with superior laryngeal or hypoglossal nerve abnormalities, and patients with severe untreated gastroesophageal reflux (which would likely impair healing and recuperation) are relatively contraindicated with aggressive glossectomy for benign disease because postoperative dysphagia and edema, which are common. The current technique demonstrates low morbidity and gives the surgeon the ability to perform less-aggressive staged procedures, which reduces concerns about dysphagia in this population. Enlarged tongue size has been associated with obesity. In the severely obese, medical or surgical weight loss should be considered and discussed as an alternative when appropriate.13 Risks of the procedures must be weighed against the alternative treatments and procedural benefits.
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Figure 4 Anatomy of the internal neurovascular structures of the tongue is shown in a midsaggital dissection of a cadaver tongue. Mandible (1), oblique segment of lingual artery (2), profunda linguae (3), anterior segment of lingual artery (4), hypoglossal nerve (hgn), and hyoid (H) are shown in (A). Coronal view of tongue imaged with ultrasound and Doppler identifies the point of medial deviation of lingual artery (arrows) and allows identification of the profunda linguae (B).
Surgical procedure Glossectomy may be performed at a single setting or as a staged multistep procedure. Procedures may be done using local anesthesia with sedation or general anesthesia using nasotracheal intubation. No additional airway support is usually required. Surgeons must always assess the need for possible tracheotomy or prolonged intubation in a patient with a difficult airway. Glossectomy alone may not be a single definitive treatment and it is part of a comprehensive treatment of the upper airway. Postoperative care and treatment should account for the persistence of disease. The amount of tissue removal required is ill-defined. A general rule associates more aggressive resection with a greater complication rate and risks. To reduce these risks, conservative resection is recommended, and staged additional procedure be performed as needed. Steps include (1) anesthesia/preparation, (2) anatomy and landmarks, (3) exposure and mucosal incision, (4) tissue removal, (5) exposure valleculae, and (6) closure and postoperative care.
Anatomic landmarks The location of the lingual artery is the key landmark to identify the location of the neurovascular pedicle of the tongue. The artery has 3 segments within the body of the tongue. These include the oblique, profunda lingua, and anterior segments (Figure 4). Knowledge of this anatomy is critical. Damage to the neurovascular bundle is a risk of the procedure. To reduce this risk, ultrasound is used to map and mark the location of the anterior segment of the lingual artery. The position of the neurovascular bundle varies between individuals and changes with traction and movement of the tongue. Posteriorly, the lingual artery enters the lateral and ventral tongue running obliquely in a direction roughly parallel to the inferior border of the mandible. The artery courses medial to the hyoglossus muscle and the hypoglossal nerve. Approximately, 2 cm from the posterior border of the tongue, the artery changes direction and courses vertically (profunda lingua segment). The profunda lingua segment is approximately 2 cm from the midline but, along this segment, moves more to the midline. The artery
moves closer to the midline such that the anterior segment lying just lateral to the genioglossus muscle is 1 cm from the midline. Overall, the course of the vessel is somewhat sigmoid shaped in the tongue. The hypoglossal nerve runs lateral to the vessel in the oblique segment and anterior and inferior of the profunda and anterior segments. The anterior segment begins a surface landmark which approximates 1 to 1.5 cm from the frenulum. Published cadaver studies show the artery is located an estimated 2.7 cm inferior and 1.6 cm lateral to the foramen cecum.14 Caution must be used with any static measures since the tongue is mobile. Mapping of the tongue is performed with a transoral ultrasound before or at the beginning of the procedure. Ultrasound identifies the medial position of the anterior segment, and it is marked on the dorsum of the tongue. The location of the vessels is then mapped posteriorly. At the level of where the vessels diverge laterally, the profunda segment is located. Posterior to this is the oblique segment, which is more laterally located in the tongue. Transoral ultrasound does not usually identify this segment (transcervical can visualize). The profunda is marked on the surface of the tongue. A wide “safe area” for resection in the posterior tongue between the oblique portion of the neurovascular pedicle is identified.
Anesthesia/preparation When performed under local anesthesia, a semirecumbent position with the head of bed elevated 30° is used. Conscious sedation using anesthesia guidance is recommended, with careful instructions about the depth of sedation. Patients need to be relaxed but be able to follow commands and handle oral secretions. A rapidly adjustable agent allows titration to effect. During periods of greater stimulation, sedation may be briefly augmented and then rapidly reduced. A combination of preoperative midazolam, ketamine infusion, and supplemental short-acting narcotics has been used with success. A small shoulder roll (or intravenous bag of saline) may be used. The patient’s mandibular lower teeth are covered with a tooth guard to protect the undersurface of the tongue with aggressive traction. A bite block assists the patient in holding his or her mouth open.
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Figure 5 Glossectomy steps are depicted. The primary area to be excised is posterior oral and hypopharyngeal tongue (A). Local anesthesia is facilitated by bending the injection needle (B). Midline retraction suture should be placed as far posteriorly as possible (C). After the midline incision is created, 2 lateral traction sutures are placed, and a plasma wand is used to progressively excise tissue (D).
Preoperative oral antisepsis is important using chlorhexidine gluconate 0.12% for at least 60 seconds. Prophylactic antibiotics consisting of both a broad-spectrum cephalosporin (cephalexin) and anaerobic coverage (metronidazole) are administered. Dexamethasone 10 mg is administered for one dose and prednisone 20 mg is administered for 3 or 4 days postoperatively to reduce secondary hyperinflammation and pain. Sites of the midline traction suture and the midline incision are marked; topical benzocaine applied,
and local anesthetic (1% lidocaine with 1/100,000 epinephrine) and sodium bicarbonate (4 mg/mL; ie, 1 mL of a 40 mg/mL diluted in 10 mL of solution) is infiltrated into the sites of the midline traction suture, the midline incision, and in the tongue muscle lateral to the incision and posterior to the circumvallate papillae (Figure 5A and B). Using general anesthesia, intubation is nasotracheal. Exposure and visualization may be worse with general anesthesia, and the surgeon is unable to monitor tongue mobil-
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ity. As a result, excision is more conservative with more care anteriorly and posterolaterally under general anesthesia.
Exposure and mucosal incision Exposure of the tongue dorsum is obtained using 3 traction sutures (1 midline and 2 lateral). Placement of the midline suture should be as far posteriorly as it can be placed (Figure 5C). Gauze is used to gently pull the tongue forward and then a large silk retention stitch is placed. The tongue can now be aggressively pulled forward. An incision using electrocautery is made in the midline beginning anterior to the circumvallate papillae. Electrocautery reduces the clogging of the suction port of the coblation wand with the friable lingual mucosa. The incision is as posterior as visualization allows. The coblation wand (Evac 70 tonsil and adenoid wand, Arthrocare, Sunnyvale, CA) using a medium-to-low saline flow at an energy setting of 6 (maximal 9) is then used to deepen the midline trench. Brief pulsed applications of energy avoid excess saline flow to enter the hypopharynx. The plasma current may “leak” from the anesthetized field if energy setting is too high and the setting is kept as low as possible (Coblator II setting of 6). This “leak” is usually associated with a sensation of gag and not acute pain. In severe cases, a glossopharyngeal nerve block may be considered but has never been performed in the author’s experience. During dissection, attention must be taken to maintain a midline orientation. This is done by frequently rechecking the orientation and position of the procedure. After initial incision and “trenching,” 2 traction sutures are placed in laterally on each edge of the incision (Figure 5D). Using anterior and lateral traction, the surgeon and assistant may now expose the posterior midline tongue muscle. “Hands-free” traction may be performed by using a small elastic drain looped through a hemostat and clipped to the drape to provide a gentle pull.
Tissue removal Using a 30° angled rigid fiberoptic scope held by the assistant or surgeon, the surgical field is visualized. While the surgeon views the monitor, he or she excises the midline tongue. Under local anesthesia, a tunnel is created, leaving a posterior rim of mucosa intact between the glossectomy cavity and the valleculae (Figure 6B), which allows any excess saline to collect in the glossectomy cavity and not spill into the hypopharynx or larynx. Lateral tongue tissue is excised. Additional local anesthesia is infiltrated using a bent 22-gauge spinal needle.
served with this procedure but the potential of a bleeding vessel in this location should be kept in mind. After removal of the midline segment, prolapse of tongue tissues generally obliterates the space created. The wound is inspected for hemostasis, and 1 or 2 absorbable sutures are placed anteriorly. These sutures decrease dead space and reduce the formation of an excessive furrow in the midline of the tongue. If an excessive furrow forms, this can be eliminated by excising the mucosal lining with reclosure. The wound is left open posteriorly to allow drainage of any fluids and to reduce the possibility of a closed space abscess which could be life-threatening (Figure 6D).
Postoperative care Postoperative close monitoring of blood pressure reduces the risk of postoperative hemorrhage. Aggressive prophylactic antibiotic treatment (antistreptoccocal) is continued for 1 week. A gastroesophageal reflux treatment protocol is given to all patients. To decrease antibacterial load, chlorhexadine rinses and or mycelex trouche are used for 1 week postoperatively. Benzocaine lozenges, ice, and narcotics control pain. Patients can be started on a liquid or pureed diet on day one. Aspiration is a risk until local anesthesia has worn off. Tongue swelling, edema, and pain often are minor in the acute postoperative period, which is in marked contrast to prior more traumatic glossectomy techniques. No special swallowing instructions are necessary. More severe dysphagia and pain occur on postoperative days 2 to 4 and are thought to be secondary to hyperinflammation from a wound in a contaminated cavity.
Case report 30-year-old male presented with symptoms of severe snoring (loudness of a 7 on 10-point visual analog scale [VAS] scale), sleepiness (rated 7 on a 10-point VAS scale), fatigue, and obstructive sleep apnea. Polysomnography demonstrated residual Apnea Hypopnea Index of 45 events per hour after septoplasty and tonsillectomy. Treatment with nasal continuous positive airway pressure was intolerable despite trials of different masks, humidification, and habituation. Under local anesthesia with sedation, a multilevel airway reconstruction was performed on the patient and included intranasal piriform apeturotomy, proximal palatoplasty, lateral pharyngoplasty, and partial glossectomy. Follow-up at 7 months demonstrated residual AHI less than 10 events per hour, with VAS snoring and sleepiness rated at 0 and 1 (on a 10-point scale), respectively. The patient’s weight is unchanged, and he desires no further treatment.
Exposure valleculae and closure When the majority of the glossectomy has been performed, the posterior mucosa and muscle are incised exposing the valleculae and epiglottis (Figure 6C). Historically, on reaching the area of the valleculae, a hyoid branch of the lingual artery was often encountered with bleeding controlled with suction electrocautery. This has not been ob-
Discussion Various studies have evaluated glossectomy for OSAS. Few controlled or randomized trials have been performed. The authors of several case series that described using CO2 laser, electrocautery, radiofrequency, and traditional surgery have reviewed glossectomy outcomes. The initial description by
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Figure 6 Dorsal view of glossectomy is shown. Traction suture and midline incision (A); retraction, initial exposure, and excision (B); completed excision and exposure of proximal valleculae (C); and closure of anterior wound leaving posterior wound open (D).
Fujita et al6 of a posterior midline glossectomy (MLG) for sleep apnea reduced the Respiratory Distress Index score by 50% in 42% of patients. Mickelson and Rosenthal,8 performing MLG in a small number of morbidly obese patients with a different technique, demonstrated a 25% success rate. In a cohort study combining UPPP and MLG, individuals retrospectively classified as Friedman stage 3 (with an expected success rate of 5% to 10% with UPPP alone) demonstrated a success rate of 60%. Woodson and Fujita,9 using a technique described as lingualplasty in a group of patients who previously underwent a failed uvulopalatopharyngoplasty, demonstrated a 67% intermediate-term clinical success rate, reducing Respiratory Distress Index score to fewer than 20 events per hour. Multiple studies have reported midline glossectomy or tongue reduction procedures combined with uvulopalatopharyngoplast.15,16
Tongue volume reduction with ablational radiofrequency has been studied using both case series, cohort, and randomized evidence.17,18 Long-term results show improvement 2 years or longer from the start of treatment. A transcutaneous transhyoid cervical approach to reduce tongue base size (average tongue base reduction of 24 cm3) and reposition the hyolingual complex has a reported success rates of 80%. Complications rates vary on the aggressiveness of the procedure and include bleeding, tongue edema, and prolonged dysphagia and range from 5% to 25%. In summary, partial glossectomy has been extensively described as part of the treatment of OSAS. The current technique of excision using a plasma wand device reduces significant volume with less morbidity than previous excisional techniques. Volumetric reduction compared with radiofrequency is immediate and of greater magnitude similar
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to aggressive techniques that have previously demonstrated high success rates. Further evaluation is needed to better define the role and population best to treat with this technique.
References 1. Morrison DL, Launois SH, Isono S, et al: Pharyngeal narrowing and closing pressures in patients with obstructive sleep apnea. Am Rev Respir Dis 148:606-611, 1993 2. Robinson S, Ettema SL, Brusky L, et al: Lingual tonsillectomy using bipolar radiofrequency plasma excision. Otolaryngol Head Neck Surg 134:328-330, 2006 3. Krespi YP, Har-El G, Levine TM, et al: Laser Lingual Tonsillectomy. Laryngoscope 99:131-135, 1989 4. Wouters B, van Overbeek JJM, Buiter CT, et al: Laser surgery in lingual tonsil hyperplasia. Clin Otolaryngol 14:291-296, 1989 5. Yoskovitch A, Samaha M, Sweet R: Suction cautery use in lingual tonsillectomy. J Otolaryngol 29:117-118, 2000 6. Fujita S, Woodson BT, Clark JL, et al: Laser midline glossectomy as a treatment for obstructive sleep apnea. Laryngoscope 101:805-809, 1991 7. Jacobs I, Gray R, Todd NW: Upper airway Obstruction in Children With Down Syndrome. Arch Otolaryngol Head Neck Surg 122:945950, 1996 8. Mickelson S, Rosenthal L: Midline glossectomy and epiglottidectomy for obstructive sleep apnea syndrome. Larynogoscope 107:614-619, 1997
9. Woodson BT, Fujita S: Clinical experience with lingualplasty as part of the treatment of severe obstructive sleep apnea. Otolaryngology 107:40-48, 1992 10. Powell NB, Riley RW, Guilleminault C: Radiofrequency tongue base reduction in sleep-disordered breathing: A pilot study. Otolaryngol Head Neck Surg 120:656-664, 1999 11. Woodson BT, Steward DL, Weaver EM, et al: A randomized trial of temperature-controlled radiofrequency, continuous positive airway pressure, and placebo for obstructive sleep apnea syndrome. Otolaryngol Head Neck Surg 128:848-861, 2003 12. Robinson S, Lewis R, Norton A, et al: Ultrasound-guided radiofrequency submucosal tongue-base excision for sleep apnoea: A preliminary report. Clin Otolaryngol 28:341-345, 2003 13. Do K, Ferreyra H, Healy J, et al: Does tongue size differ between patients with and without sleep-disordered breathing? Larynogoscope 110:1552-1555, 2000 14. Lauretano AM, Li KK, Caradonna DS, et al: Anatomic location of the tongue base neurovascular bundle. Laryngoscope 107:1057-1059, 1997 15. Andsberg U, Jessen M: Eight years of follow-up, uvuloplatopharygoplasty combined with midline glossectomy as a treatment of obstructive sleep apnoea syndrome. Acta Otolaryngol Suppl 542:175-178, 2000 16. Elasfour A, Miyazaki S, Itasaka Y, et al: Evaluation of uvulopalatopharyngoplasty in treatment of obstructive sleep apnea syndrome. Acta Otolaryngol 537:52-56, 1998 17. Chabolle F, Wagner I, Blumen M, et al: Tongue base reduction with hyoepiglottoplasty: A treatment for severe obstructive sleep apnea”. Larynogoscope 109:1273-1279, 1999 18. Moore KE, Phillips C: practical method for describing patterns of tongue-base narrowing (modification of Fujita) in awake adult patients with obstructive sleep apnea. J Oral Maxillofac surg 60:252-260, 2002
Innovative technique for lingual tonsillectomy and midline posterior glossectomy for obstructive sleep apnea B. Tucker Woodson, MD, FACS From the Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin. KEYWORDS Obstructive sleep apnea; Surgery; Lingual tonsil; Tongue; Glossectomy; Local anesthesia; Low morbidity; Endoscope; Plasma; Coblation
Hypopharyngeal airway obstruction may result from abnormal or disproportionate tongue base anatomy or lingual tonsil hypertrophy. Partial glossectomy and lingual tonsillectomy may be difficult and excessively morbid procedures in the sleep apnea population. Techniques are described using plasma surgery tools, combined with endoscopy, that allow for improved visualization and more complete removal of lingual tonsils and low morbidity mucosal sparing excisional glossectomy. © 2007 Elsevier Inc. All rights reserved.
Obstructive sleep apnea syndrome (OSAS) results from a complex scenario initiated with a structurally small upper airway followed by airway collapse and obstruction, loss of compensatory wake and sleep reflexes, increased ventilatory effort, arousal, hypoventilation, and asphyxia during sleep. The etiology of the small upper airway in adults may include an abnormal craniofacial structure, excessive soft tissue for the available space, and obesity. Enlarging or removing the obstruction from the airway may prevent the cascade into sleep apnea and snoring. Multiple structural abnormalities contribute to airway obstruction. Otolaryngologists historically have used uvulopalatopharyngoplasty (UPPP) to treat patients with OSAS, but this treatment fails to address other airway abnormalities that are not limited to the upper pharynx. Both primary and secondary sites of obstruction occur in the lower airway.1 Hypopharyngeal obstruction may involve the tongue base, lateral hypopharynygeal walls, lingual tonAddress reprint requests and correspondence: B. Tucker Woodson, MD, FACS, Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, 9200 W. Wisconsin Avenue, Milwaukee, WI 53226. E-mail address: [email protected]. 1043-1810/$ -see front matter © 2007 Elsevier Inc. All rights reserved. doi:10.1016/j.otot.2007.03.004
sils, and supraglottic larynx. The use of multiple procedures to treat these sites have met with varying effectiveness and morbidity. In this work, 2 innovative procedures to treat the lower pharynx, lingual tonsillectomy and transoral submucosal endoscopic assisted glossectomy, are described. Both have the advantage of lower patient morbidity compared with previously described techniques.
Lingual tonsillectomy Hypertrophic lingual tonsils may partially or completely obstruct the retrolingual airway. Removing these tissues enlarges the airway and improves breathing, swallowing, and sleeping. Although conceptually straightforward, removing lingual tonsils may be difficult, particularly in the sleep apnea patient who exhibits mandibular and maxillary hypoplasia and or macroglossia. Transoral exposure and access are difficult. Additionally, patients with OSAS are at greater risk of airway complications resulting from the use of anesthesia. Traditional methods have included cautery, cryotherapy, and laser, among others. Laser by means of the carbon dioxide or KTP-Yag lasers commonly have been
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used. This method, however, restricts visualization to a straight line and the exposure is worsened by even small amounts of bleeding and char. Because of the difficulty in adequately performing the procedure, the author’s experience was to limit lingual tonsillectomy only to the more severe cases of lingual tonsil hypertrophy. Recently, a new tool and improved methods of visualization have reduced these difficulties.2 This new technique uses a bipolar radiofrequency plasma surgery tool called “coblation” (Arthrocare Corp, ENTec division, Sunnyvale, CA). This device creates a low-temperature plasma field. The corona of activated ions disassociates tissues, which are removed in a saline irrigation field. Removal of lymphoid tissue and muscle is relatively bloodless and without char. This tool minimizes tissue trauma, intraoperative bleeding, char formation, and postoperative pain. Its ease of use, malleable probe, and ability to work outside the lumen of the laryngoscope and with rigid fiberoptic scopes allows removal of tissue that would typically be extremely difficult using laser or other techniques.
Lingual tonsillectomy evaluation Evaluation routinely includes flexible nasopharyngoscopy/laryngoscopy. Candidates who will likely benefit have a bulk of lingual tonsils that obscure visualization of the root of the epiglottis/valleculae on supine awake examination. In some cases, a magnetic resonance scan (MRI) can discriminate muscle, fat, and lymphoid tissue and define the actual volume of hypertrophic tonsils (Figure 1). Before surgery, medical treatment of lingual tonsil hypertrophy may include addressing infection, allergy, and gastroesphageal reflux disease. Limited data exist on the effectiveness of these medical therapies. Risks of neoplastic disease in the adult warrant further evaluation, especially with recent changes in size or symptoms or if other lymphadenopathy exists.
Lingual tonsillectomy method The procedure is performed with the patient under general nasotracheal anesthesia. Nasotracheal intubation allows displacement of the endotracheal tube away from the base of the tongue. Exposure of the valleculae in the OSAS patient usually requires a suspension rigid laryngoscope (such as a Weerda bi-valved laryngoscope). Tissue is removed using a plasma surgery device (Evac 70 tonsil and adenoid coblation wand) with a coblator II generator (setting 7-9, Arthrocare Corp, ENTec division). Optimum dissection can be obtained by bending the malleable wand approximately 30° and inserting the probe between the corner of the mouth and outside of the laryngoscope, with the tip of the probe being visualized in the operative field beyond the tip of the laryngoscope (Figure 2). Counter pressure over the hyoid region may further augment exposure. After removal of the bulk of lingual tonsils, a 70° angled telescope may allow better inspection of the hypopharynx and precise removal of additional tissue. In selected cases, it markedly improves visualization after lingual tonsils have
Figure 1 Midsagittal (A) and coronal (B) magnetic resonance imaging demonstrating enlarged lingual tonsils filling the vallecular space and tipping the epiglottis posteriorly and contrast-enhanced axial magnetic resonance imaging depicting highlighted region of lingual tonsils obstructing the airway.
been debulked. Steps of this method include a bite block to open the mouth, a lower tooth guard to protect the ventral surface of the tongue, a posteriorly placed traction suture on the dorsum of the tongue, and vigorous traction on the tongue. Using an irrigation system further improves visualization of the valleculae, hypopharynx, and larynx. The angled scope may identify lingual tonsil tissue lateral to the midline that has often been difficult to identify and safely remove. In some adults (in contrast to experience in children), the anatomy does not allow visualization using rigid telescopes without the concomitant use of a rigid scope and
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Operative Techniques in Otolaryngology, Vol 18, No 1, March 2007 (average of 3) on a visual analog scale from 0 to 10. No primary bleeding has occurred, and secondary bleeding has been less than 5%. Blood loss during the procedures is minimal and has ranged from approximately 0 mL to 50 mL, with an average of 20 mL. Patients do not require tracheostomy tube placement under normal conditions. No significant airway edema of the hypopharynx or larynx has been observed postoperatively. Even in cases of mild mucosal injury to the epiglottis by the plasma wand, edema has been mild. Risks of the procedure include airway obstruction, bleeding, dysphagia, change in taste, and persistence of sleep disordered breathing. Before the combined use of the angled 70° fiberoptic scope, residual lateral lymphoid tissue was not uncommon and is less with the improved exposure provided by the scope.
Discussion
Figure 2 Placement of the coblation wand (A) to the side of the laryngoscope (B) leaves the lumen unobstructed and allows better visualization and easier dissection of the lingual tonsils and base of tongue region.
a rigid scope combined with an endoscope or the operating microscope may be needed. Other technical points also can help. Irrigation is improved using a pressure bag applied to the irrigation bag to deliver a continuous stream of fluid onto the operative field against gravity (especially when the tip of the probe is directed upward). Dissection is initiated at the base of the valleculae, and the laryngoscope is slowly withdrawn until the foramen cecum is identified. This is the anterior midline limit of dissection. The device hemostatically excises lymphoid tissue; bleeding vessels may indicate muscle and can be controlled using the device coagulation mode. Major bleeding vessels may suggest a deeper dissection beyond the tonsil bed or beyond the intended surgical field into the supraglottis. Suction electrocautery also may be used. In some individuals with OSA even the most experienced endoscopist cannot expose the surgical field. In these cases, exposure may be achieved by a midline posterior glossectomy. Recuperation has been similar between individuals undergoing lingual tonsillectomy alone and combined with partial glossectomy. Lingual tonsillectomy using this method has been used for both modest and massive hypertrophy. Operative time varies from 10 to 30 minutes for modest hypertrophy to several hours with massive hypertrophy. Care should be taken in prolonged cases to intermittently release compression on the tongue; this is done at least once every hour. Immediately after the procedure, patient pain appears to be mild to moderate, with pain scores ranging from 0 to 7
A variety of techniques have been described in the literature for lingual tonsillectomy, including sharp dissection, laser, suction diathermy, cryotherapy, and the use of an ultrasonic coagulating dissector.3-6 The use of laser techniques carry a small risk of airway fire and require more equipment, setup, and specialized endotracheal tubes. In addition, dissection is slower compared with the coblation technique. Suction diathermy chars tissue, and cryotherapy yields unpredictable results. Traditionally, lingual tonsil removal has been extremely difficult. Classical approaches using a tonsillectomy gag do not expose the valleculae in sleep apnea patients. Laryngoscopic visualization allows exposure, but the procedure is difficult. The current technique with a malleable curved instrument is more versatile and allows for precise and rapid removal. The lack of char, excellent hemostasis, minimal thermal trauma and edema, and lower pain levels reduce morbidity of the procedure and expand the potential indications for lingual tonsillectomy.
Transoral submucosal endoscopic-assisted glossectomy Glossectomy treats lower pharyngeal by modifying the shape and size of the soft tissue tongue base, hypopharynx, and supraglottic tissues.7-9 Airway space is increased by reducing the bulk of soft tissue. Although conceptually simple, using traditional methods, morbidity of the procedure may be high and exposure difficult. Risks of airway obstruction, bleeding, infection, and dysphagia have been reported as many as 25% of patients. Glossectomy morbidity and complications have been associated with the aggressiveness of resection and the nature of the surgical tools used. The more tissue was removed or damaged, the worse the perioperative recovery (pain, edema, dysphagia, bleeding, infection). The relatively high rate of morbidity has restricted the procedure to a limited population of patients who were not candidates for other therapies or procedures. Alternatively, radiofrequency tissue ablation has been used to reduce tongue volume.10,11 The rate of patient morbidity when this tool is used is lower, and evidence-based medi-
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Figure 3 Moore Tongue base classification is depicted. Assessment is performed endoscopically with subjective rating of hypopharyngeal obstruction pattern. Three general patterns are described based on the levels (low tongue base, proximal tongue base, combined) of perceived narrowing and obstruction. Type A describes isolated upper tongue base obstruction. A common etiology for this is lingual tonsil hypertrophy. Type C describes lower tongue base obstruction (retro-hyoid/retro-epiglottic). Type B is combined.
cine shows a definite clinical effect. The therapy requires multiple sessions, and volume reduction often is inadequate to result in the desired clinical outcome. An alternative excisional procedure that preserves mucosa and with less morbidity than conventional glossectomy has been described.12 Postoperative seroma and untreated wound deadspace caused persistent swelling. Concerns about these risks, as well as infection, nerve, and vessel injury, prompted the development of the current method. The innovative technique described differs from previous techniques in allowing graded tissue excision (single or staged), preservation of tongue mucosa and taste buds, reduced tissue trauma pain and edema, and low complication rates. The procedure is performed under local or general anesthesia. Glossectomy removing significant bulk of the posterior tongue can be performed under local anesthesia and assisted with sedation. Excision is performed transorally via a midline incision. Tissue is removed submucosally, with the surgeon taking care to preserve taste buds and minimizing pain. The use of ultrasound identifies the lingual vessels as anatomic landmarks to avoid damage to important structures. Exposure to the midline tongue muscles is obtained with 3 traction sutures. A plasma knife excises tissue progressively posteriorly and laterally. Disintegrated tissue is removed by a continuous flow of saline. Surgery is performed using endoscopic visualization. Patients may resume an oral diet rapidly after the procedure.
Glossectomy evaluation Hypopharyngeal airway obstruction due to relative macroglossia is the primary indications for glossectomy. Structural assessment of obstructive tongue base anatomy may be performed using several methods, including a modified Malampatti 3 or 4, Fujita Type II or type III, and Moore Class A and B. All describe soft-tissue abnormalities to the tongue base. The Moore classification defines abnormal
hypopharyngeal anatomy into 3 basic types, that is, A, B, and C (Figure 3). Type A demonstrates high tongue base obstruction, type B demonstrates obstruction in both the high and low tongue base and retro-epiglottic obstruction, and type C demonstrates retro-epiglottic obstruction alone. Because the current procedure demonstrates lower morbidity and patient acceptance (and is more similar to ablational radiofrequency), the population that are potential candidates is broader in contrast to procedures that result in greater morbidity, which are most appropriately applied in patients who suffer severe disease and in whom alternative procedures are not appropriate. Contraindications to glossectomy (for the treatment of sleep apnea) may include patients with swallowing or speech problems or with a lingual thyroid. Previous techniques of glossectomy may affect the circumvallate papillae and taste buds to a greater degree, and minor (and often transient) changes in taste have been observed. However, in certain professions and individuals, even minor changes in taste would cause potential disability. The current technique attempts to preserve mucosa and taste buds and has not been observed to alter taste. Patients with poor pulmonary reserve (who would be at severe risk if swallowing difficulties developed), patients with superior laryngeal or hypoglossal nerve abnormalities, and patients with severe untreated gastroesophageal reflux (which would likely impair healing and recuperation) are relatively contraindicated with aggressive glossectomy for benign disease because postoperative dysphagia and edema, which are common. The current technique demonstrates low morbidity and gives the surgeon the ability to perform less-aggressive staged procedures, which reduces concerns about dysphagia in this population. Enlarged tongue size has been associated with obesity. In the severely obese, medical or surgical weight loss should be considered and discussed as an alternative when appropriate.13 Risks of the procedures must be weighed against the alternative treatments and procedural benefits.
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Figure 4 Anatomy of the internal neurovascular structures of the tongue is shown in a midsaggital dissection of a cadaver tongue. Mandible (1), oblique segment of lingual artery (2), profunda linguae (3), anterior segment of lingual artery (4), hypoglossal nerve (hgn), and hyoid (H) are shown in (A). Coronal view of tongue imaged with ultrasound and Doppler identifies the point of medial deviation of lingual artery (arrows) and allows identification of the profunda linguae (B).
Surgical procedure Glossectomy may be performed at a single setting or as a staged multistep procedure. Procedures may be done using local anesthesia with sedation or general anesthesia using nasotracheal intubation. No additional airway support is usually required. Surgeons must always assess the need for possible tracheotomy or prolonged intubation in a patient with a difficult airway. Glossectomy alone may not be a single definitive treatment and it is part of a comprehensive treatment of the upper airway. Postoperative care and treatment should account for the persistence of disease. The amount of tissue removal required is ill-defined. A general rule associates more aggressive resection with a greater complication rate and risks. To reduce these risks, conservative resection is recommended, and staged additional procedure be performed as needed. Steps include (1) anesthesia/preparation, (2) anatomy and landmarks, (3) exposure and mucosal incision, (4) tissue removal, (5) exposure valleculae, and (6) closure and postoperative care.
Anatomic landmarks The location of the lingual artery is the key landmark to identify the location of the neurovascular pedicle of the tongue. The artery has 3 segments within the body of the tongue. These include the oblique, profunda lingua, and anterior segments (Figure 4). Knowledge of this anatomy is critical. Damage to the neurovascular bundle is a risk of the procedure. To reduce this risk, ultrasound is used to map and mark the location of the anterior segment of the lingual artery. The position of the neurovascular bundle varies between individuals and changes with traction and movement of the tongue. Posteriorly, the lingual artery enters the lateral and ventral tongue running obliquely in a direction roughly parallel to the inferior border of the mandible. The artery courses medial to the hyoglossus muscle and the hypoglossal nerve. Approximately, 2 cm from the posterior border of the tongue, the artery changes direction and courses vertically (profunda lingua segment). The profunda lingua segment is approximately 2 cm from the midline but, along this segment, moves more to the midline. The artery
moves closer to the midline such that the anterior segment lying just lateral to the genioglossus muscle is 1 cm from the midline. Overall, the course of the vessel is somewhat sigmoid shaped in the tongue. The hypoglossal nerve runs lateral to the vessel in the oblique segment and anterior and inferior of the profunda and anterior segments. The anterior segment begins a surface landmark which approximates 1 to 1.5 cm from the frenulum. Published cadaver studies show the artery is located an estimated 2.7 cm inferior and 1.6 cm lateral to the foramen cecum.14 Caution must be used with any static measures since the tongue is mobile. Mapping of the tongue is performed with a transoral ultrasound before or at the beginning of the procedure. Ultrasound identifies the medial position of the anterior segment, and it is marked on the dorsum of the tongue. The location of the vessels is then mapped posteriorly. At the level of where the vessels diverge laterally, the profunda segment is located. Posterior to this is the oblique segment, which is more laterally located in the tongue. Transoral ultrasound does not usually identify this segment (transcervical can visualize). The profunda is marked on the surface of the tongue. A wide “safe area” for resection in the posterior tongue between the oblique portion of the neurovascular pedicle is identified.
Anesthesia/preparation When performed under local anesthesia, a semirecumbent position with the head of bed elevated 30° is used. Conscious sedation using anesthesia guidance is recommended, with careful instructions about the depth of sedation. Patients need to be relaxed but be able to follow commands and handle oral secretions. A rapidly adjustable agent allows titration to effect. During periods of greater stimulation, sedation may be briefly augmented and then rapidly reduced. A combination of preoperative midazolam, ketamine infusion, and supplemental short-acting narcotics has been used with success. A small shoulder roll (or intravenous bag of saline) may be used. The patient’s mandibular lower teeth are covered with a tooth guard to protect the undersurface of the tongue with aggressive traction. A bite block assists the patient in holding his or her mouth open.
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Figure 5 Glossectomy steps are depicted. The primary area to be excised is posterior oral and hypopharyngeal tongue (A). Local anesthesia is facilitated by bending the injection needle (B). Midline retraction suture should be placed as far posteriorly as possible (C). After the midline incision is created, 2 lateral traction sutures are placed, and a plasma wand is used to progressively excise tissue (D).
Preoperative oral antisepsis is important using chlorhexidine gluconate 0.12% for at least 60 seconds. Prophylactic antibiotics consisting of both a broad-spectrum cephalosporin (cephalexin) and anaerobic coverage (metronidazole) are administered. Dexamethasone 10 mg is administered for one dose and prednisone 20 mg is administered for 3 or 4 days postoperatively to reduce secondary hyperinflammation and pain. Sites of the midline traction suture and the midline incision are marked; topical benzocaine applied,
and local anesthetic (1% lidocaine with 1/100,000 epinephrine) and sodium bicarbonate (4 mg/mL; ie, 1 mL of a 40 mg/mL diluted in 10 mL of solution) is infiltrated into the sites of the midline traction suture, the midline incision, and in the tongue muscle lateral to the incision and posterior to the circumvallate papillae (Figure 5A and B). Using general anesthesia, intubation is nasotracheal. Exposure and visualization may be worse with general anesthesia, and the surgeon is unable to monitor tongue mobil-
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ity. As a result, excision is more conservative with more care anteriorly and posterolaterally under general anesthesia.
Exposure and mucosal incision Exposure of the tongue dorsum is obtained using 3 traction sutures (1 midline and 2 lateral). Placement of the midline suture should be as far posteriorly as it can be placed (Figure 5C). Gauze is used to gently pull the tongue forward and then a large silk retention stitch is placed. The tongue can now be aggressively pulled forward. An incision using electrocautery is made in the midline beginning anterior to the circumvallate papillae. Electrocautery reduces the clogging of the suction port of the coblation wand with the friable lingual mucosa. The incision is as posterior as visualization allows. The coblation wand (Evac 70 tonsil and adenoid wand, Arthrocare, Sunnyvale, CA) using a medium-to-low saline flow at an energy setting of 6 (maximal 9) is then used to deepen the midline trench. Brief pulsed applications of energy avoid excess saline flow to enter the hypopharynx. The plasma current may “leak” from the anesthetized field if energy setting is too high and the setting is kept as low as possible (Coblator II setting of 6). This “leak” is usually associated with a sensation of gag and not acute pain. In severe cases, a glossopharyngeal nerve block may be considered but has never been performed in the author’s experience. During dissection, attention must be taken to maintain a midline orientation. This is done by frequently rechecking the orientation and position of the procedure. After initial incision and “trenching,” 2 traction sutures are placed in laterally on each edge of the incision (Figure 5D). Using anterior and lateral traction, the surgeon and assistant may now expose the posterior midline tongue muscle. “Hands-free” traction may be performed by using a small elastic drain looped through a hemostat and clipped to the drape to provide a gentle pull.
Tissue removal Using a 30° angled rigid fiberoptic scope held by the assistant or surgeon, the surgical field is visualized. While the surgeon views the monitor, he or she excises the midline tongue. Under local anesthesia, a tunnel is created, leaving a posterior rim of mucosa intact between the glossectomy cavity and the valleculae (Figure 6B), which allows any excess saline to collect in the glossectomy cavity and not spill into the hypopharynx or larynx. Lateral tongue tissue is excised. Additional local anesthesia is infiltrated using a bent 22-gauge spinal needle.
served with this procedure but the potential of a bleeding vessel in this location should be kept in mind. After removal of the midline segment, prolapse of tongue tissues generally obliterates the space created. The wound is inspected for hemostasis, and 1 or 2 absorbable sutures are placed anteriorly. These sutures decrease dead space and reduce the formation of an excessive furrow in the midline of the tongue. If an excessive furrow forms, this can be eliminated by excising the mucosal lining with reclosure. The wound is left open posteriorly to allow drainage of any fluids and to reduce the possibility of a closed space abscess which could be life-threatening (Figure 6D).
Postoperative care Postoperative close monitoring of blood pressure reduces the risk of postoperative hemorrhage. Aggressive prophylactic antibiotic treatment (antistreptoccocal) is continued for 1 week. A gastroesophageal reflux treatment protocol is given to all patients. To decrease antibacterial load, chlorhexadine rinses and or mycelex trouche are used for 1 week postoperatively. Benzocaine lozenges, ice, and narcotics control pain. Patients can be started on a liquid or pureed diet on day one. Aspiration is a risk until local anesthesia has worn off. Tongue swelling, edema, and pain often are minor in the acute postoperative period, which is in marked contrast to prior more traumatic glossectomy techniques. No special swallowing instructions are necessary. More severe dysphagia and pain occur on postoperative days 2 to 4 and are thought to be secondary to hyperinflammation from a wound in a contaminated cavity.
Case report 30-year-old male presented with symptoms of severe snoring (loudness of a 7 on 10-point visual analog scale [VAS] scale), sleepiness (rated 7 on a 10-point VAS scale), fatigue, and obstructive sleep apnea. Polysomnography demonstrated residual Apnea Hypopnea Index of 45 events per hour after septoplasty and tonsillectomy. Treatment with nasal continuous positive airway pressure was intolerable despite trials of different masks, humidification, and habituation. Under local anesthesia with sedation, a multilevel airway reconstruction was performed on the patient and included intranasal piriform apeturotomy, proximal palatoplasty, lateral pharyngoplasty, and partial glossectomy. Follow-up at 7 months demonstrated residual AHI less than 10 events per hour, with VAS snoring and sleepiness rated at 0 and 1 (on a 10-point scale), respectively. The patient’s weight is unchanged, and he desires no further treatment.
Exposure valleculae and closure When the majority of the glossectomy has been performed, the posterior mucosa and muscle are incised exposing the valleculae and epiglottis (Figure 6C). Historically, on reaching the area of the valleculae, a hyoid branch of the lingual artery was often encountered with bleeding controlled with suction electrocautery. This has not been ob-
Discussion Various studies have evaluated glossectomy for OSAS. Few controlled or randomized trials have been performed. The authors of several case series that described using CO2 laser, electrocautery, radiofrequency, and traditional surgery have reviewed glossectomy outcomes. The initial description by
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Figure 6 Dorsal view of glossectomy is shown. Traction suture and midline incision (A); retraction, initial exposure, and excision (B); completed excision and exposure of proximal valleculae (C); and closure of anterior wound leaving posterior wound open (D).
Fujita et al6 of a posterior midline glossectomy (MLG) for sleep apnea reduced the Respiratory Distress Index score by 50% in 42% of patients. Mickelson and Rosenthal,8 performing MLG in a small number of morbidly obese patients with a different technique, demonstrated a 25% success rate. In a cohort study combining UPPP and MLG, individuals retrospectively classified as Friedman stage 3 (with an expected success rate of 5% to 10% with UPPP alone) demonstrated a success rate of 60%. Woodson and Fujita,9 using a technique described as lingualplasty in a group of patients who previously underwent a failed uvulopalatopharyngoplasty, demonstrated a 67% intermediate-term clinical success rate, reducing Respiratory Distress Index score to fewer than 20 events per hour. Multiple studies have reported midline glossectomy or tongue reduction procedures combined with uvulopalatopharyngoplast.15,16
Tongue volume reduction with ablational radiofrequency has been studied using both case series, cohort, and randomized evidence.17,18 Long-term results show improvement 2 years or longer from the start of treatment. A transcutaneous transhyoid cervical approach to reduce tongue base size (average tongue base reduction of 24 cm3) and reposition the hyolingual complex has a reported success rates of 80%. Complications rates vary on the aggressiveness of the procedure and include bleeding, tongue edema, and prolonged dysphagia and range from 5% to 25%. In summary, partial glossectomy has been extensively described as part of the treatment of OSAS. The current technique of excision using a plasma wand device reduces significant volume with less morbidity than previous excisional techniques. Volumetric reduction compared with radiofrequency is immediate and of greater magnitude similar
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to aggressive techniques that have previously demonstrated high success rates. Further evaluation is needed to better define the role and population best to treat with this technique.
References 1. Morrison DL, Launois SH, Isono S, et al: Pharyngeal narrowing and closing pressures in patients with obstructive sleep apnea. Am Rev Respir Dis 148:606-611, 1993 2. Robinson S, Ettema SL, Brusky L, et al: Lingual tonsillectomy using bipolar radiofrequency plasma excision. Otolaryngol Head Neck Surg 134:328-330, 2006 3. Krespi YP, Har-El G, Levine TM, et al: Laser Lingual Tonsillectomy. Laryngoscope 99:131-135, 1989 4. Wouters B, van Overbeek JJM, Buiter CT, et al: Laser surgery in lingual tonsil hyperplasia. Clin Otolaryngol 14:291-296, 1989 5. Yoskovitch A, Samaha M, Sweet R: Suction cautery use in lingual tonsillectomy. J Otolaryngol 29:117-118, 2000 6. Fujita S, Woodson BT, Clark JL, et al: Laser midline glossectomy as a treatment for obstructive sleep apnea. Laryngoscope 101:805-809, 1991 7. Jacobs I, Gray R, Todd NW: Upper airway Obstruction in Children With Down Syndrome. Arch Otolaryngol Head Neck Surg 122:945950, 1996 8. Mickelson S, Rosenthal L: Midline glossectomy and epiglottidectomy for obstructive sleep apnea syndrome. Larynogoscope 107:614-619, 1997
9. Woodson BT, Fujita S: Clinical experience with lingualplasty as part of the treatment of severe obstructive sleep apnea. Otolaryngology 107:40-48, 1992 10. Powell NB, Riley RW, Guilleminault C: Radiofrequency tongue base reduction in sleep-disordered breathing: A pilot study. Otolaryngol Head Neck Surg 120:656-664, 1999 11. Woodson BT, Steward DL, Weaver EM, et al: A randomized trial of temperature-controlled radiofrequency, continuous positive airway pressure, and placebo for obstructive sleep apnea syndrome. Otolaryngol Head Neck Surg 128:848-861, 2003 12. Robinson S, Lewis R, Norton A, et al: Ultrasound-guided radiofrequency submucosal tongue-base excision for sleep apnoea: A preliminary report. Clin Otolaryngol 28:341-345, 2003 13. Do K, Ferreyra H, Healy J, et al: Does tongue size differ between patients with and without sleep-disordered breathing? Larynogoscope 110:1552-1555, 2000 14. Lauretano AM, Li KK, Caradonna DS, et al: Anatomic location of the tongue base neurovascular bundle. Laryngoscope 107:1057-1059, 1997 15. Andsberg U, Jessen M: Eight years of follow-up, uvuloplatopharygoplasty combined with midline glossectomy as a treatment of obstructive sleep apnoea syndrome. Acta Otolaryngol Suppl 542:175-178, 2000 16. Elasfour A, Miyazaki S, Itasaka Y, et al: Evaluation of uvulopalatopharyngoplasty in treatment of obstructive sleep apnea syndrome. Acta Otolaryngol 537:52-56, 1998 17. Chabolle F, Wagner I, Blumen M, et al: Tongue base reduction with hyoepiglottoplasty: A treatment for severe obstructive sleep apnea”. Larynogoscope 109:1273-1279, 1999 18. Moore KE, Phillips C: practical method for describing patterns of tongue-base narrowing (modification of Fujita) in awake adult patients with obstructive sleep apnea. J Oral Maxillofac surg 60:252-260, 2002