Oropharyngeal stenosis is caused by adhesion of the anterior pillars and inferior tonsillar fossa to the tongue base. Symptoms may include dyspnea on exertion, dysphagia, poor weight gain, and obstructive sleep apnea. Some patients may be asymptomatic . Before 1940, most cases were due to infection, mainly pharyngeal syphilis . After 1940, the most common etiology of OPS has been reported to be surgical trauma associated with adeno-tonsillectomy . Risk factors for developing OPS after adeno-tonsillectomy include excessive cautery, postoperative bleeding and infection, and keloid tendency , but the prevalence has been reported to be very small . This case was thought to be a rare case of OPS caused by adeno-tonsillectomy. Other causes include airway burn and systemic inflammatory diseases such as sarcoidosis  and Behçet’s syndrome .
However, recent studies report higher prevalence of postoperative OPS among the patients who underwent more complicated upper-airway surgery such as pharyngoplasty for obstructive sleep apnea (OSA) [6, 7]. Prager et al. indicated the prevalence of postoperative OPS to be 8.2 % in their retrospective chart review of 104 pediatric patients who underwent multilevel upper airway surgery including lingual tonsillectomy . Cohen et al. reviewed their 65 adult patients who underwent surgery for OSA. Among the patients who underwent UPPP (uvulopalatopharyngoplasty) or TORS (trans-oral robotic surgery) including tongue-base resection, the prevalence of postoperative OPS was 7.8 % . In both reports, the authors indicate a single-stage procedure including tongue-base resection as a risk factor, along with the aforementioned risk factors of postoperative OPS [8, 9].
Several case series of post-surgical OPS are written by otolaryngologists [2, 3, 8, 9]. One of them briefly commented on unexpected difficult airway during the induction of general anesthesia , but most of them did not. Although there is a case report of unanticipated difficult intubation due to an undiagnosed pharyngeal stenosis , this complication is still not widely recognized by anesthesiologists.
Our case raises two issues into discussion; the lack of preoperative interview and the awareness of postoperative OPS can cause unexpected difficult airway. For this particular case, there was a serious communication problem. Due to the language barrier, we were unable to obtain the information about the patient’s history of adeno-tonsillectomy and subsequent dysphagia, because the patient considered it as a trivial problem. Ideally, medical interpreters should always be available, but this was not the case for our facility, as well as for many others. With the increase of patients unable to speak Japanese, this issue is becoming more common. In addition, even if we had no language issues and were aware of her surgical history, we could have overlooked her OPS because it is a very rare complication of adeno-tonsillectomy. However, considering that we may have more chance to encounter postsurgical OPS in the future with the development of complicated upper-airway surgery, we should be able to recognize and anticipate this complication. In our pre-operative interview, we should specifically ask patients about their history of upper-airway surgery. If the patient has had surgery, an evaluation through detailed interview and close observation should be performed. We should also consult an otolaryngologist if we suspect a complication. Laryngofiberscopy will provide us with useful information for planning how to secure the patient’s airway.