You are in: eMedicine Specialties > Otolaryngology and Facial Plastic Surgery > NASAL AND SINUS DISEASES Nasopharyngeal StenosisArticle Last Updated: Jan 29, 2007AUTHOR AND EDITOR INFORMATIONSection 1 of 11
  Author: Gauri Mankekar, MBBS, MS, DNB, PhD, Consulting Surgeon, Department of Otolaryngology, PD Hinduja National Hospital, Mumbai Coauthor(s): Simione Lew-Gor, MBChB, MRCS(Ed), DLO, Honorary Senior House Officer, Department of Ear, Nose and Throat, Great Ormond Street Hospital For Children, London Editors: Lanny Garth Close, MD, Chair, Professor, Department of Otolaryngology-Head and Neck Surgery, Columbia University College of Physicians and Surgeons; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Gregory C Allen, MD, Assistant Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine; Christopher L Slack, MD, Otolaryngology-Facial Plastic Surgery, Private Practice, Associated Coastal ENT; Medical Director, Treasure Coast Sleep Disorders; Arlen D Meyers, MD, MBA, Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine Author and Editor Disclosure Synonyms and related keywords: nasopharyngeal stenosis, nasopharynx, NPS, steroid injections, scar lysis, skin grafts, Z-plasty repair, mucosal flaps, laterally based pharyngeal flap, bivalved palatal transposition flap, stents, silastic grommets, CO2 laser, plasma hook, mitomycin C tonsillectomy, adenoidectomy, velopharyngeal surgery, syphilis, rhinoscleroma, lupus, diphtheria, scarlet fever, bullous pemphigoid, tuberculosis, acid burns INTRODUCTIONSection 2 of 11
  The nasopharynx is defined as the superior portion of the pharynx that lies between the choanae of the nasal cavity and the oropharynx (ie, the level of the posterior limit of the soft palate). Stenoses of this area are rare. They are classified according to their etiology, which may be primary (ie, due to a disease process) or secondary (ie, iatrogenic). However, most current cases are understood to be postoperative complications of tonsillectomy, adenoidectomy, or uvulopalatoplasty. Because of a high incidence of recurrence, the treatment of this condition is challenging. Even with optimal planning and surgical technique, many patients require repeat operations to obtain a satisfactory result. Therefore, many treatment modalities are being tried to cure this problem. Nasopharyngeal stenosis (NPS) should not be confused with choanal atresia. Choanal atresia is a congenital deformity that causes a narrow or completely obstructed airway at the choanae that often extends into the nasal cavity. Generally, choanal atresia includes a bony component. Conversely, NPS, by definition, is outside of the nasal cavity, is not congenital, and is caused by scar tissue secondary to a disease process or traumatic insult. History of the ProcedureHistorically, many procedures have been used in an attempt to correct NPS.
FrequencyNPS is relatively rare. The true incidence of this rare condition is difficult to assess. In 1944, in a 10-year review of 100,000 tonsillectomies and adenoidectomies at the Manhattan Eye, Ear, and Throat Hospital, Imperatori found only 3 cases.1 This condition has no sex predilection. EtiologyMost cases of NPS are caused by inexpert surgery and postsurgical scarring. Overly enthusiastic adenoidectomies or uvulopalatoplasties are the usual operations that lead to NPS. However, tonsillectomies, surgery of the soft palate, and pharyngeal surgeries to treat velopharyngeal incompetence can also cause NPS. The literature prior to 1929 reports that most cases were due to the gumma of tertiary syphilis of the mouth, pharynx, and palate and the treatment of these lesions with caustic chemicals. Other rare causes in the literature include rhinoscleroma, lupus, diphtheria, scarlet fever, bullous pemphigoid, tuberculosis, and acid burns. PathophysiologyNPS may appear months to years after adenoidectomy or uvuloplasty. It results from excess mucosal removal during surgery followed by scar contracture and maturation. The degree and extent of the stenosis may vary from patient to patient. The scar tissue may cause a circumferential narrowing, a web, or bands. A discrete circumferential web or a long stenosed segment that forms a narrow tunnel several centimeters long may be present. ClinicalThe severity of symptoms is related to the degree of NPS. The history includes a traumatic insult (iatrogenic, traumatic, or infective) to the nasopharynx. Symptoms include mouth breathing, snoring, rhinorrhea, hyponasality, dysphagia, otalgia, loss of hearing (otitis media), and anosmia. If these symptoms develop following a surgical procedure in the nasopharynx, NPS should be considered. Upon examination, the mucosa of the nasal airway may be blue and boggy, as is seen with nasal obstruction. Airflow through the nostrils may be reduced or eliminated. Scar tissue that involves the soft palate and tonsil pillars may be visible. A postnasal mirror or a rigid or flexible nasendoscope aids in making the stenosis visible. Krespi and Kacker proposed a scale to grade the severity of NPS: NPS type I (mild NPS), NPS type II (moderate NPS), and NPS type III (severe NPS), wherein the entire palate fuses with the posterior and lateral palatal wall, leaving a residual nasopharynx opening with a diameter of less than 1 cm. INDICATIONSSection 3 of 11
The severity of the symptoms must be balanced against the difficulty of surgical repair and the possibility of recurrence and multiple operations. Many patients are young and have to live with potentially progressive symptoms for many years. Symptoms are usually severe at presentation, and surgical intervention is usually required. RELEVANT ANATOMYSection 4 of 11
The nasopharynx can be thought of as an essentially cuboidal space. The roof is formed by the base of the skull and the sphenoid sinus, anteriorly bounded by the choanae and posterior portion of the vomer. The floor consists of the superior surface of the soft palate and uvula. Incorporated into the lateral walls are the eustachian tube orifices and the Rosenmüller fossae. The posterior wall is the superior extension of the posterior pharyngeal wall. The mucosa of the nasopharynx is the respiratory type. The midline usually contains a large deposit of lymphoid tissue that often extends into the Rosenmüller fossae. The shape of the nasopharynx changes with respiration and deglutition. During respiration, the soft palate is drawn away from the posterior pharyngeal wall to open an airway. During deglutition, the palate elevates and contacts the nasopharynx so that food and fluid do not pass into the nose. CONTRAINDICATIONSSection 5 of 11
Surgical correction of nasopharyngeal stenosis (NPS) may be contraindicated in the presence of the patient's comorbidities and inability to tolerate anesthesia or surgery, but the symptoms, which are usually severe at presentation, usually require surgical intervention. WORKUPSection 6 of 11
Imaging Studies
TREATMENTSection 7 of 11
Medical therapyNasopharyngeal stenoses (NPS) are typically challenging to correct, and often recur. Prevention is the best form of treatment. Careful operative technique, judicious use of electrocautery, and adequate preoperative evaluation for adenoidectomy or uvulopalatoplasty during the primary surgery are essential to prevent NPS. In cases of mild scarring, McLaughlin et al found some success with triamcinolone acetonide injections, but the only curative treatments for acquired NPS are surgical.2 Surgical therapyA thorough preoperative assessment of the lesion is needed to ensure that the best surgical option for the individual lesion is used. Current surgical options include steroid injections, scar lysis with CO2 laser or plasma hook, skin grafts, Z-plasty repair, various local mucosal flaps, insertion of prosthetic stents, silastic grommets, nasopharyngeal obturators, and topical application of mitomycin C. Two methods of mucosal flap repair are described below. Bivalved palatal transposition flap Described by Toh et al in 2000, this procedure is performed with the patient under general anesthesia with orotracheal intubation.3 The patient is supine with the neck extended. A mouth gag is used to expose the oropharynx. Local anesthetic (1% lidocaine) with adrenaline (1:100,000) is infiltrated into the operative site. A transverse and slightly curvilinear incision is marked out on either side of the stenosis. This incision is extended inferolaterally to the expected position of the base of the posterior tonsillar pillars. The stenosis is then bivalved by elevating mucosal flaps on a submucosal plane off the oral and nasopharyngeal surfaces of the soft palate. The superiorly based flap represents the nasopharyngeal surface of the soft palate, and the inferiorly based flap from the oropharyngeal side is attached to the posterior pharyngeal wall. The posterior half of the bivalved palate is then transposed anteriorly and sutured to the incision on the oral side of the soft palate. The inferiorly based mucosal flap is transposed superiorly and sutured to the denuded portion of the posterior pharyngeal wall. Laterally based pharyngeal flap For this procedure, as described by Cotton in 1985, the patient is anesthetized and local anesthetic and adrenaline are infiltrated, as in the bivalved palatal transposition flap.4 A lateral incision is made through the scar tissue into the lateral pharyngeal wall. The incision is deepened as far as possible without damaging important structures in the parapharyngeal space. The mucosa is now elevated to allow a considerable amount of scar tissue removal. The entire posterior pharyngeal wall is elevated as a laterally based pharyngeal flap (thus, only one side of the NPS is dissected). Smith has used sternocleidomastoid myocutaneous flap reconstruction for NPS.13 CO2 laser Krespi and Kacker have reported on the largest number of patients who have undergone successful NPS correction with a CO2 laser.5 After scar tissue was excised with the laser, patients with moderate-to-severe stenosis received a nasopharyngeal obturator to be worn at night for 2-6 months to prevent restenosis. The CO2 laser was reported to cause less thermal damage to adjacent tissue and minimal mucosal de-epithelialization, and it offered better hemostasis. Jones et al used a CO2 laser under general anesthesia to create an opening in the nasopharynx.6 The patients were then fitted with removable and adjustable palatal obturators to keep the nasopharynx open. A daytime insert piece with a small obturator hole for diminished velopharyngeal insufficiency and a night-time piece without an insert to maximize recumbent airflow were also used. The obturators were removed after 6 months, and a topical application of mitomycin C was used as a fibroblast inhibitor. These authors monitored their patients with polysomnography and have reported satisfactory results. Plasma hook Madgy et al treated 3 cases of severe NPS with plasma radiofrequency–based coblation.7 A crescent of scar tissue was excised with the plasma hook. The crescent extended approximately 5 mm laterally to each side and approximately 5 mm posteriorly to the pharyngeal wall. In one case, they applied mitomycin C to the raw edges to reduce scarring and recurrence. They reported that the plasma hook excision incurs less epithelial damage and produces a smaller area of collagen denaturation than conventional electrocautery. In addition, the procedure itself is easy to perform and offers satisfactory results. Eppley et al compared the use of (1) preoperatively fabricated stents made from a clasped palatal appliance onto which hollow acrylic conduits were extended through surgically re-created pharyngeal ports with (2) intraoperatively fashioned silastic grommets.8 They found that the palatal stents were less tolerated than the silastic grommets. In addition, the grommet stent obviates the need for extensive preoperative preparation and is easy to insert and remove; also, during the stenting, an exchange of air occurs. Patient tolerance was found to be better with the grommet stents, which could, therefore, be retained longer with better results. Intraoperative detailsTwo methods of mucosal flap repair are described below. Bivalved palatal transposition flap Described by Toh et al in 2000, this procedure is performed with the patient under general anesthesia with orotracheal intubation. The patient is supine with the neck extended.3 A mouth gag is used to expose the oropharynx. Local anesthetic (1% lidocaine) with adrenaline (1:100,000) is infiltrated into the operative site. A transverse and slightly curvilinear incision is marked out on either side of the stenosis. This incision is extended inferolaterally to the expected position of the base of the posterior tonsillar pillars. The stenosis is then bivalved by elevating mucosal flaps on a submucosal plane off the oral and nasopharyngeal surfaces of the soft palate. The superiorly based flap represents the nasopharyngeal surface of the soft palate, and the inferiorly based flap from the oropharyngeal side is attached to the posterior pharyngeal wall. The posterior half of the bivalved palate is then transposed anteriorly and sutured to the incision on the oral side of the soft palate. The inferiorly based mucosal flap is transposed superiorly and sutured to the denuded portion of the posterior pharyngeal wall. Laterally based pharyngeal flap For this procedure, as described by Cotton in 1985, the patient is anesthetized and local anesthetic and adrenaline are infiltrated as for the bivalved palatal transposition flap.4 A lateral incision is made through the scar tissue into the lateral pharyngeal wall. The incision is deepened as far as possible without damaging important structures in the parapharyngeal space. The mucosa is now elevated to allow a considerable amount of scar tissue removal. The entire posterior pharyngeal wall is elevated as a laterally based pharyngeal flap (thus, only one side of the NPS is dissected). The laterally based pharyngeal flap is elevated as a mucomuscular flap at the plane of the prevertebral fascia. The inferior limit of the flap is dissected as far back as possible. A back-cut is now performed inferiorly to mobilize the pharyngeal flap. This mucomuscular flap is mobilized and sewn into position, covering the denuded area of the lateral walls of the nasopharynx and oropharynx. Postoperative detailsA nasopharyngeal tube is left in for 24-48 hours to allow the flap to settle, to maintain an airway, and to help with suctioning. The patient is maintained on clear fluids for up to a week. Postoperative antibiotics are used. Follow-upMonitor the patient to check that the surgery is successful and the patient has no complications. In the long-term, polysomnography helps to monitor for restenosis. COMPLICATIONSSection 8 of 11
Postoperative airway problems and hemorrhage have not been reported. Velopharyngeal reflux has been reported but is transient and gradually resolves. The main complication is restenosis. This condition is common, and the literature suggests that a repeat operation is performed in 10-20% of patients. OUTCOME AND PROGNOSISSection 9 of 11
Even with optimal planning and surgical technique, many patients require repeat operations to obtain a satisfactory result. Giannoni et al showed that acquired nasopharyngeal stenosis (NPS) symptoms had an average onset time of 3.1 weeks postsurgery. Stepnick reported recurrent scarring and stenosis within 6 weeks of treating NPS with the placement of a free flap. FUTURE AND CONTROVERSIESSection 10 of 11
Since the discovery and widespread use of antibiotics, the incidence of nasopharyngeal stenosis (NPS) has declined. The main etiologies in current practice include tonsillectomy, adenoidectomy, and velopharyngeal surgery. Thus, a rare condition has become even rarer. The nature of the stenosis renders it difficult to treat successfully. This, coupled with its rarity, leaves most surgeons with limited experience in the condition and little to read about it in the published literature. Mucosal flaps of the palate and pharynx seem to be the most successful technique for repair. However, the use of many different types of flaps is reported in the literature. REFERENCESSection 11 of 11
Nasopharyngeal Stenosis excerpt Article Last Updated: Jan 29, 2007 |
