Computed tomographic scan of the nasopharynx showing nasopharyngeal soft tissue and inflammatory changes of the right maxillary and ethmoid sinuses.
Total choanal stenosis secondary to adenoidectomy performed with a laser.
Postoperative result of the patient shown in Figure 2 three months after repair using a transpalatal and endoscopic technique showing a small but patent choanae. This child is without significant nasal obstruction.
Giannoni C, Sulek M, Friedman EM, Duncan NO. Acquired Nasopharyngeal StenosisA Warning and Review. Arch Otolaryngol Head Neck Surg. 1998;124(2):163-167. doi:10.1001/archotol.124.2.163
Copyright 1998 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.1998
To present and discuss the clinical presentation and treatment planning in children with acquired nasopharyngeal stenosis (NPS) following tonsillectomy and adenoidectomy.
Tertiary care center.
Patients and Other Participants
Nine children identified over 2 years (1995-1996) with newly diagnosed NPS were evaluated. Seven of these children underwent adenoidectomy using a potassium titanyl phosphate laser technique at a neighboring facility. These children were aged 15.6 to 62.1 months at the time of original surgery, and all presented with nasal obstruction and mouth breathing beginning within 10 weeks after surgery. In addition, 5 had newly documented obstructive sleep apnea.
Of the 9 children, 1 required a tracheotomy. After undergoing an adenoidectomy, chronic rhinosinusitis developed and aggressive medical treatment failed in 4 children. Time from symptom onset to diagnosis of NPS ranged from 2 to 34 months. The diagnosis of NPS depends on obtaining a thorough medical history and conducting a physical examination that includes nasopharyngoscopy. Most children underwent a computed tomographic scan prior to repair. The scarring encountered in these patients involved the soft palate and the posterior pharyngeal wall and/or choanae bilaterally. Five children had no identifiable eustachian tube opening into the nasopharynx, and all 5 children had chronic otitis media with effusion or persistent otorrhea.
Nasopharyngeal stenosis following adenoidectomy and/or tonsillectomy is difficult to correct. Multiple surgeries may be required to relieve the obstruction. Standard operative techniques using the lateral pharyngeal flap and transpalatal or endoscopic intranasal approaches were adapted to the clinical situation. Prolonged use of nasal stents is mandatory to produce a nasopharyngeal opening. Adjunctive treatment may include pressure equilization tubes. However, the best treatment remains prevention.
THE COMMONLY reported complications of tonsillectomy and adenoidectomy in children include postoperative hemorrhage, nausea, fever, and velopharyngeal insufficiency.1,2 Nasopharyngeal stenosis (NPS) is a rare and serious complication of tonsillectomy and adenoidectomy. The incidence has not been reported. Previously, NPS occurred most commonly as a result of the treatment of pharyngeal syphilis.3 Today, NPS most commonly results as a complication of palatopharyngoplasty, tonsillectomy, and/or adenoidectomy.4- 6 Cotton6 reported 7 cases presenting during a 7-year period. Nine cases in a 2-year period is unexpected. Of 8 of these cases, 7 were associated with the use of the potassium titanyl phosphate (KTP) laser in the nasopharynx. We present these cases, discuss the etiologic factors in development of NPS, and report endoscopic and transpalatal repair techniques.
Nine children with symptoms of nasal obstruction, who were later diagnosed as having NPS, were referred to the pediatric otolaryngology service at Texas Children's Hospital, Houston, over a 2-year period (1995-1996). The children's primary procedure was performed by 2 community otolaryngologists (Table 1). The children were aged 15.6 to 62.1 months (average, 27.6 months). Five underwent adenoidectomy, and 4 underwent tonsillectomy and adenoidectomy. Patients' symptoms began an average of 3.1 weeks postoperatively (range, immediately to 10 weeks). The delay in diagnosis averaged longer than 1 year (range, 2-34.9 months; average, 13.4 months). All 5 patients who underwent adenoidectomy and 2 of the patients who underwent tonsillectomy and adenoidectomy had their procedure performed with the KTP laser. The settings were 26 to 30 W at continuous power,with the beam setting in the defocused mode. Following surgery these children presented with loud snoring and mouth breathing. Five patients underwent sleep studies and were documented as having obstructive sleep apnea. One child had severe obstructive apnea requiring tracheotomy.
Complete evaluation included nasopharyngoscopy and, in most patients, computed tomographic scanning (Figure 1). Nasopharyngeal stenosis occurred at 2 levels in these patients (Table 2). Of the 9 children, 8 had stenosis of the choanae, total or near total in most cases (Figure 2). Four children had stenosis at the level of the inferior edge of the soft palate, the most usual site. No protection of the palate with ointment or moistened gauze was found in the operative notes. These 4 cases include 3 patients in whom the scarring began at the choanae and solidly extended posteriorly and inferiorly to the inferior edge of the soft palate. In 5 children, the torus tubarius could not be identified.
Five patients were treated initially using an intranasal approach. In 1 patient, dilation was performed, and in the 4 others, an endoscopic removal of scar tissue was performed. Pharyngeal mucosa was preserved whenever possible. In 3 patients (2 initial and 1 revision), a transpalatal approach was used. The posterior portion of the vomer was removed. In the patients who underwent endoscopy, the scar tissue was débrided in an effort to preserve pharyngeal mucosa. Two patients were treated using a lateral pharyngeal flap.
Of the 8 patients with choanal involvement, 7 were treated with nasal stenting, as in the repair of a congenital choanal atresia. In the patients in whom the soft palate was involved as well, polymeric silicone tubular stents were fashioned to extend beyond the corrected area (extending into the oropharynx). A second endoscopy was performed 6 weeks after surgery when the stents were removed, and a third endoscopy was performed using anesthesia several months later. In 2 patients, minor revisions consisting of removal of localized granulation tissue were performed at the third endoscopy. These 2 patients were both reevaluated 6 weeks later and found to be patent (Figure 3).
Of the 9 children, 7 are without significant symptoms of nasal obstruction. Patients 2 and 4 had minor revisions and are now doing well. Patient 7 has moderate symptoms. This child has patent choanae but a thin scar band at the palatal level. A recommendation of a revision has been made. In patient 8, a lateral pharyngeal flap failed, and revision was performed using a transpalatal approach. Reevaluation of this child prior to revision revealed severe choanal stenosis and obliteration of tonsil pillars with scarring that extended from the posterior and inferior aspects of the choanae to the midoropharynx. This child required a tracheotomy for severe obstructive sleep apnea. A 6-month delay after the revision is planned before decannulation is attempted for adequate healing to occur and to avoid the viral respiratory season. Patient 9, although without nasal obstruction, has significant hypomobility of the palate secondary to scarring that has resulted in velopharyngeal insufficiency.
The diagnosis of NPS depends on an alert, inquisitive physician. Two patients had seen otolaryngologists, other than their primary surgeon, prior to their presentation at Texas Children's Hospital. The symptoms of obstructive sleep apnea, nasal obstruction, mouth breathing, and persistent rhinosinusitis in a child following adenoidectomy should raise suspicion of this rare, but clinically significant, abnormality. A complete examination that includes nasopharyngoscopy is paramount to obtaining the diagnosis. In young children, an examination using anesthesia may be required.
Stevenson3 gives a thorough, chronological history of the repairs used for NPS beginning with the first recorded procedure by Nichols in 1896 and ending with his own experience in 1968. Today, the laterally based pharyngeal flap is one method of repair when the NPS consists of stenosis at the level of the soft palate.6 However, it is not always successful and depends on the presence of healthy pharyngeal tissue to rotate onto the stenosed surface. Other authors7,8 have reported alternative repair options. Van Duyne and Coleman7 had success treating NPS after palatopharyngoplasty by using an outpatient, staged, carbon dioxide laser release. Microvascular procedures, such as the radial forearm free flap, have been suggested but are not practical in young children.8
An overview of surgical lasers and wound healing is important in understanding the origin of this complication. The acronym laser stands for light amplification by the stimulated emission of radiation. Lasers result in vaporization or coagulation of tissue when light energy is absorbed. The absorption of energy by a tissue is wavelength dependent. Power density is a measure of the concentration of laser energy: watts per square centimeter. Power density varies linearly by power output and varies logarithmically by spot size (smaller spot size has more concentrated energy). The beam may also be used with a focused or defocused beam, in other words, the laser interacts with the tissue at the laser focal length or not at the focal length. A defocused beam will cover a larger tissue area than the focused beam. The laser causes different thermal effects at different levels in the tissue. The most superficial to deeper levels of tissue effects are, respectively, vaporization, necrosis, thermal conductivity, and normal tissue.9
Many lasers are used in otolaryngologic surgery: carbon dioxide, argon, argon tunable dye, flash lamp pulsed dye, KTP, and neodymium:YAG. The children in this series had procedures performed using the KTP laser. The KTP laser has a wavelength of 532 nm and a depth of penetration and thermocoagulation similar to that of the argon laser and is strongly absorbed by hemoglobin. When used in a defocused mode, as in our patients, the depth of thermocoagulation extends to 1 to 2 mm.10 Wound healing from laser procedures is delayed by several weeks compared with scalpel techniques due to the depth of injury. To protect against beam penetration of normal tissues, one might use a moistened gauze pad or apply antibiotic ointment to protect normal tissues.
These patients were significant for the presence of deep scar tissue with the absence of identifiable muscle tissue in the nasopharynx, palate, and tonsil pillars. Also significant was the presence of scarring at 2 levels of the nasopharynx. First, there was stenosis of the choanae, usually with complete obliteration of the nasopharynx. Second, there was also scarring of the naso-oropharynx at the level of the soft palate and tonsil pillars with scarring to the posterior walls of the oropharynx. The goal was to treat these 2 levels.
Choanal stenosis was complete or near total in most patients and was approached as in cases of congenital choanal atresia. Endoscopic techniques were used in 5 patients initially and 2 patients undergoing revisions. Pharyngeal mucosa was preserved when possible by débriding scar tissue under an incision site but leaving the overlying mucosa intact. The mucosa was then held in place by absorbable sutures or the stents. In 3 patients, a transpalatal approach was used because of the lack of landmarks and extreme density of the scarring. The transpalatal approach assisted in the repair in 2 regards: It gave access to the choanae when landmarks were absent and facilitated opening of the associated scarring of the soft palate to the posterior nasopharyngeal wall. Pharyngeal mucosa was carefully spared whenever possible.
Nasal stenting plays an important role in the success of these procedures.11 Removal of the stents was performed using anesthesia 6 weeks after surgery, and a third examination was performed at a later time if the children could not be examined thoroughly in the office. The lateral pharyngeal flap did not achieve significantly superior results in our series. The condition of one child was improved, but this child had a persistently hypomobile palate, and another child had near-total restenosis and required a major revision.
Of the 9 children, 7 are doing well and 2 are improved. Revisions were required in 3 children and recommended in another. It should be noted that these children have increased problems with upper respiratory tract infections and all are being observed regularly and treated aggressively when viral upper respiratory tract infections or rhinosinusitis symptoms develop. Myringotomy and tube placement were performed in the 5 children with chronic otitis media.
This series is presented as the potential problems associated with laser adenoidectomy. The symptoms of obstructive sleep apnea, nasal obstruction, mouth breathing, and rhinosinusitis in a child following adenoidectomy should alert the otolaryngologist to evaluate the child for this rare, but clinically significant, abnormality. These cases are unusual because of the severity and depth of the scarring and the presence of choanal stenosis in the majority of cases. Standard operative techniques were adapted to the clinical situation. While lateral pharyngeal flap closure is ideal, this was not possible in most of these patients because of the depth and extent of scarring. In our patients, a successful outcome as measured by relief of symptoms was obtained in the majority of cases by evaluating each case independently and using endoscopic, transpalatal, and pharyngeal flap procedures as required. The choanal and palatal openings were never completely normal in size but were functionally adequate in 7 of 9 patients. The status of the patient who underwent a tracheotomy has been downgraded, and decannulation is planned at the end of the season of viral upper respiratory tract infections. Adjunctive treatment would include pressure equalization tubes, especially in those patients with obliterated torus tubarius, and aggressive treatment of rhinitis. The best treatment for NPS, however, remains prevention.
Accepted for publication August 7, 1997.
Presented at the combined otolaryngology spring meetings in Scottsdale, Ariz, May 15, 1997.
Reprints: Marcelle Sulek, MD, Department of Pediatric Otolaryngology, Texas Children's Hospital, 1102 Bates St, Suite 340, Houston, TX 77030.