Introduction
Over the last two decades, there has been significant advancement in digital endoscopes, with the use of office-based, unsedated transnasal oesophagoscopy becoming more prevalent.Reference Wellenstein, Schutte, Marres, Honings, Belafsky and Postma1,Reference Roof and Amin2 The diagnostic value of transnasal oesophagoscopy has been shown to be comparable to traditional practice using rigid endoscopes but without requiring an operating theatre or needing general anaesthetic or sedation. Rigid endoscopes can pose an issue for patients who have an unexpected anatomical variant, resulting in difficult airway access, or in those unfit for anaesthesia.Reference Price, Sharma, Snelling, Bennett, Qayyum and Bradnam3
Evidence has shown that transnasal oesophagoscopy is well tolerated in head and neck patients, with a completion rate of more than 96 per cent compared with 79 per cent for endoscopic procedures performed via the transoral route. The instrument ports integrated into the scope have allowed a variety of procedures beyond diagnostic capabilities including tissue biopsy, tracheoesophageal puncture placements and oesophageal balloon dilatation. A couple of studies looking at such applications have demonstrated the enhanced role of transnasal oesophagoscopy for patient safety and have found it to be cost-effective while being well tolerated by patients.Reference Wellenstein, Schutte, Marres, Honings, Belafsky and Postma1,Reference Roof and Amin2
This study aimed to review the existing literature to investigate the extended roles of transnasal oesophagoscopy within otolaryngology, from both a diagnostic and therapeutic perspective.
Materials and methods
This review was undertaken in line with Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (‘PRISMA-P’) 2015 guidelines. A literature search was performed on Embase, Cinahl and Medline® databases using the medical subject headings (‘MeSH’) of ‘transnasal oesophagoscopy’ and ‘TNO’ as well as free text words. A generic set of keywords was agreed amongst the authors to try and broaden the search as much as possible.
The initial search, conducted in January 2018, returned 445 articles, which were narrowed down to 411 articles after duplicates were removed. Two authors (LJ and AV) screened the titles independently and selected 404 abstracts that focused on transnasal oesophagoscopy performed by ENT surgeons.
A further search was conducted in January 2019 because of the time lapse between the initial search and the writing of this review, and 20 further articles were found. A further 4 articles were added from a manual search of the references. The same two authors subsequently screened the 424 abstracts independently and then went on to review 40 full papers to assess eligibility. All disagreements were resolved by discussion amongst the authors, and 16 full text articles that were relevant to our aims were selected.
The excluded papers included case reports, conference proceedings, papers that focused solely on the diagnostic application of transnasal oesophagoscopy and articles focusing on transnasal oesophagoduodenoscopy, which is performed by gastroenterologists and general surgeons. Studies containing duplicated data from previously published work were also excluded, as were review articles, editorials and letters. No restrictions were placed on study design or study population (Figure 1).
Fig. 1. Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (‘PRISMA-P’) diagram showing the search strategy for this study.
All titles, abstracts, full text articles and referencing were handled using Mendeley Desktop v1.17 (Elsevier, Amsterdam, the Netherlands) 2008–2017 reference manager. Our selection process is outlined in our Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (‘PRISMA-P’) diagram in Figure 1.
Results
Indications for transnasal oesophagoscopy
Best et al.Reference Best, Halum and Parker4 evaluated the current indications for transnasal oesophagoscopy. An online survey was sent to all 251 members of the American Broncho-Esophagological Association, and 60 members replied. Results showed that transnasal oesophagoscopy is currently used mainly for diagnostic purposes, with 28 respondents using it in the investigation of dysphagia, 17 using it for biopsy, 16 using it for laryngopharyngeal reflux (usually for persistent disease after a trial of medication), and 15 using it for the investigation of gastroesophageal reflux disease, cough and cancer screening. Respondents also noted that transnasal oesophagoscopy was used for the therapeutic procedures of foreign body removal (11 respondents) and balloon dilatation (10 respondents) in an ENT setting.
Postma et al. carried out a large study detailing the indications for transnasal oesophagoscopy in 711 patients. They noted that the most frequent indication was for patients with a diagnosis of reflux, globus or dysphagia (n = 490), for biopsy (n = 42), and for cancer surveillance (n = 45). The only therapeutic procedure that transnasal oesophagoscopy was used for in this study was removal of foreign body (n = 12).Reference Postma, Cohen, Belafsky, Halum, Gupta and Bach5
Foreign bodies
Our literature search identified two papers, a non-randomised comparative study by Shih et al. and a small case series by Bennett et al., which discussed the experience of using transnasal oesophagoscopy in the management of pharyngeal and oesophageal foreign bodies.Reference Shih, Hao, Wang and Hao6,Reference Bennett, Sharma, Price and Montgomery7 Both studies showed relatively good outcomes for foreign body identification and removal.
Foreign body identification
In the study carried out by Shih et al., foreign bodies were found in 72.1 per cent of those undergoing rigid oesophagoscopy (43 individuals). Of the 320 patients who underwent transnasal oesophagoscopy, foreign bodies were identified in 17.2 per cent (52) of individuals.Reference Shih, Hao, Wang and Hao6 Foreign bodies were identified in 5 out of 6 individuals in the Bennett et al. study. This study did not have a control group.Reference Bennett, Sharma, Price and Montgomery7
Foreign body removal
Out of the 52 foreign bodies found in the study by Shih et al., 36 were successfully removed via transnasal oesophagoscopy. The remaining 16 patients underwent rigid oesophagoscopy because of suspected oesophageal perforation or because the large size and sharp nature of the foreign bodies rendered them irremovable via transnasal oesophagoscopy.Reference Shih, Hao, Wang and Hao6 All foreign bodies were successfully removed in the group undergoing rigid oesophagoscopy as a primary procedure. Bennett et al. stated that one patient underwent direct pharyngoscopy under general anaesthetic for reasons not addressed by authors.Reference Bennett, Sharma, Price and Montgomery7
Complication rates
Neither study reported any major complication with transnasal oesophagoscopy removal of foreign bodies, or with rigid methods (rigid oesophagoscopy or direct pharyngoscopy).Reference Shih, Hao, Wang and Hao6,Reference Bennett, Sharma, Price and Montgomery7
Transoesophageal puncture
Bach et al. described one of the earliest transnasal oesophagoscopy-guided tracheoesophageal puncture procedures with the advances of fibre-optic endoscopes, whereby no complications were reported, and the procedure was completed in under 10 minutes.Reference Bach, Postma and Koufman8
Successful placement
Morrison et al. studied 13 patients who underwent transnasal oesophagoscopy-guided tracheoesophageal puncture after failed attempts using rigid oesophagoscopy and in those unfit for a general anaesthetic. Successful placement was achieved in all 13 patients.Reference Morrison, Chheda and Postma9 These results were echoed by a study by LeBert et al. which detailed 39 patients who underwent transnasal oesophagoscopy-guided secondary tracheoesophageal puncture over two years. Of the 39 patients, 25 underwent a total laryngectomy, 8 underwent a total laryngectomy with partial pharyngectomy and 14 underwent a microvascular flap reconstruction.Reference LeBert, McWhorter, Kunduk, Walvekar, Lewin and Hutcheson10 Transnasal oesophagoscopy-guided tracheoesophageal puncture was successful in 38 cases, with the remaining patient undergoing a successful flexible oesophagoscopy-guided tracheoesophageal puncture. The authors state that the sole failure was most likely a result of surgeon inexperience.Reference LeBert, McWhorter, Kunduk, Walvekar, Lewin and Hutcheson10 Difficulties with placement were a result of scar formation in four patients, nasopharyngeal stenosis in one patient and aberrant course of the oesophagus in one patient. In a retrospective study, Britt et al. reviewed 83 patients who underwent in-office transnasal oesophagoscopy-guided secondary tracheoesophageal puncture over 7 years. A successful puncture was achieved in all cases.Reference Britt, Lippert, Kammer, Ford, Dailey and McCulloch11
Voice quality after placement
LeBert et al. found that most patients (64 per cent) undergoing transnasal oesophagoscopy-guided tracheoesophageal puncture achieved very good voice quality, measured using the Performance Status Scale for Head and Neck Cancer. The authors found no correlation between individuals who had undergone radiotherapy or cricopharyngeal myotomy and the success of transnasal oesophagoscopy-guided tracheoesophageal puncture (p > 0.05).Reference LeBert, McWhorter, Kunduk, Walvekar, Lewin and Hutcheson10 A similar outcome was described by Britt et al. In their study, conversational speech was achieved in 69.9 per cent of individuals with failure of this in only 3.6 per cent as a result of anatomical defects from previous surgery.Reference Britt, Lippert, Kammer, Ford, Dailey and McCulloch11
A small study by Noel et al. followed four patients who underwent a secondary tracheoesophageal puncture using transnasal oesophagoscopy in gastric pull-up reconstruction after total laryngo-pharyngo-oesophagectomy. Although three patients had received previous radiotherapy, all four patients gained a functional voice with intelligible speech.Reference Noel, Fink, Kunduk, Schexnaildre, DiLeo and McWhorter12
Complication rates
All papers report low complication rates, with Morrison et al. reporting two minor incidents (one patient with suspected false passage and one patient who developed post-operative cellulitis, which required a course of antibiotics.Reference Morrison, Chheda and Postma9 Britt et al. reported no complications in 97.6 per cent of cases with the remaining cases experiencing bleeding from the puncture site and closure of puncture site after dislodgement of the prosthesis.Reference Britt, Lippert, Kammer, Ford, Dailey and McCulloch11 No adverse outcomes were reported in the study by LeBert et al.Reference LeBert, McWhorter, Kunduk, Walvekar, Lewin and Hutcheson10
Laser
Successful treatment of lesions
Price et al. detailed transnasal oesophagoscopy-guided vocal cord surgery using a neodymium-doped yttrium-aluminium-garnet (YAG) laser. The procedure was performed on one patient, who had two benign papillomatous lesions on his vocal cords, under local anaesthetic. The patient had undergone a previous microlaryngoscopy under general anaesthetic, which had failed due to large dentition and tongue base.Reference Price, Sharma, Snelling, Bennett, Qayyum and Bradnam3 Local anaesthetic was introduced via the transnasal flexible laryngo-oesophagoscopy, and the laser was delivered via the instrument port. There were no signs of papilloma at six weeks post-procedure.Reference Price, Sharma, Snelling, Bennett, Qayyum and Bradnam3
Halum and Moberly looked at pulsed dye and carbon dioxide (CO2) laser surgery in 10 individuals. Of these, five patients had recurrent respiratory papillomatosis and five had other benign lesions including amyloidosis (n = 1), granuloma (n = 1), varies (n = 1) and leukoplakia (n = 2). Disease reoccurred in three of the recurrent respiratory papillomatosis patients, and residual disease remained in the patients with amyloid and leukoplakia.Reference Halum and Moberly13
Koufman et al. reviewed 443 cases of laser laryngeal surgery (170 patients) for benign laryngeal lesions, including recurrent respiratory papillomas, granulomas, leukoplakia and polypoid degeneration. Three different lasers were used in the surgical procedures: 406 procedures for 151 patients were performed with the pulsed-dye laser, 10 procedures for 2 patients were performed with the CO2 laser and 27 procedures for 17 patients were performed with the thulium YAG laser.Reference Koufman, Rees, Frazier, Kilpatrick, Wright and Halum14 Transnasal oesophagoscopy using the pulsed dye laser was effective for small lesions; however, 15 per cent of patients treated for recurrent respiratory papillomatosis (9 of 59) had to have further treatment in the operating theatre because of bulky disease.Reference Koufman, Rees, Frazier, Kilpatrick, Wright and Halum14 Of the other conditions that were studied, the number of patients requiring further operative treatment varied: 20 per cent of leukoplakia patients (20 of 25) and 31 per cent of granuloma patients (6 of 19) required further treatment; however, all individuals with Reinke's oedema (12) were treated successfully. Two patients with recurrent respiratory papillomatosis underwent a CO2 laser procedure in conjunction with the pulsed dye laser and thulium YAG laser, although the aim in these cases was to control the disease rather than cure it. Disease burden was improved in both cases.Reference Koufman, Rees, Frazier, Kilpatrick, Wright and Halum14 Seventeen patients underwent a thulium YAG laser procedure to treat recurrent respiratory papillomatosis, granuloma, amyloid, vocal cord lesion, glottic web and dystonia; however, the outcomes were not stated.Reference Koufman, Rees, Frazier, Kilpatrick, Wright and Halum14
Patient satisfaction and pain scores
Of the 13 individuals studied by Mohammed et al., patient satisfaction and tolerability was high, with only 5 individuals reporting little to moderate distress during anaesthetic and 8 reporting a small degree of pain during the procedure.Reference Mohammed, Masterson and Nassif15 Halum and Moberly reported high tolerance and satisfaction of both pulsed dye and CO2 lasers in 10 individuals. Pain scores were low for both lasers, with mean pain and burning scores of 2.0 and 2.3, measured using a visual analogue scale.Reference Halum and Moberly13
Complications
No complications from the procedures were reported across all four studies.Reference Price, Sharma, Snelling, Bennett, Qayyum and Bradnam3,Reference Halum and Moberly13–Reference Mohammed, Masterson and Nassif15
Oesophageal dilatation
Oesophageal stricture is a common complication in those who have received radiotherapy as part of their head and neck cancer treatment.
Successful dilatation
The study by Howell et al. analysed 47 dilatations in 22 patients who had all undergone radiotherapy and had successful outcomes.Reference Howell, Schopper, Giliberto, Collar and Khosla16 In a study by Rees et al., describing their experience using transnasal oesophagoscopy balloon dilatation, 54 balloon dilatations were recorded in 38 patients with two procedures abandoned due to laryngospasm and gagging.Reference Rees, Fordham and Belafsky17
Complications
Although the Howell et al. study reported no major complications, minor complications including superficial lacerations to the oesophagus in three patients and self-limiting epistaxis in two patients were noted.Reference Howell, Schopper, Giliberto, Collar and Khosla16 The study by Rees et al. reported no major complications. Patient follow-up was not reported in this study.Reference Rees, Fordham and Belafsky17
Vocal cord medialisation
There was only one case study, by Montgomery et al.,Reference Montgomery, Sharma, Qayyum and Mierzwa18 reporting the use of transnasal oesophagoscopy in vocal cord medialisation using collagen. The nose and throat were anaesthetised, and the endoscope was passed transnasally until the vocal cords were viewed. Zyplast® collagen was passed down the instrument channel, where it was delivered directly into the vocal cord. The patient was then asked to phonate to determine how much collagen was needed. No complications were reported.
Discussion
Our literature review identified 16 papers describing extended roles for transnasal oesophagoscopy. The majority of the studies were small local case outcome studies. No randomised controlled trials or meta-analyses were found. All studies support the excellent safety profile of transnasal oesophagoscopy with no studies reporting major complications across all procedures.
The quality of evidence presented by each paper has been analysed in accordance with the levels of evidence system as detailed by the Oxford Centre for Evidence-based Medicine (Table 1). In addition to its safety profile, transnasal oesophagoscopy has been proven to be efficient and economical.Reference Roof and Amin2 Wellenstein et al. recorded cost savings of between €94.43 and €831.31 depending on the diagnostic procedure.Reference Wellenstein, Honings, Schutte, Herruer, van den Hoogan and Marres19 Howell et al. found that the cost savings of oesophageal dilatation via transnasal oesophagoscopy was $15 000 less compared to the same procedure in the operating theatre.Reference Howell, Schopper, Giliberto, Collar and Khosla16 With such significant benefits to the patient, surgeon and healthcare system, our aim was to determine what therapeutic procedures transnasal oesophagoscopy is currently being used for within otolaryngology and what the evidence is behind these roles.
Table 1. Summary of papers reviewed alongside the corresponding level of evidence
*The Oxford Centre for Evidence-based Medicine system was used to categorise the level of evidence.20 TNO = transnasal oesophagoscopy
Two studies examining the use of transnasal oesophagoscopy for the removal of pharyngeal or oesophageal foreign bodies, although both small sample studies, concluded that transnasal oesophagoscopy removal of foreign bodies was well tolerated, safe and effective, with the majority of foreign bodies removed or clearly excluded.Reference Shih, Hao, Wang and Hao6,Reference Bennett, Sharma, Price and Montgomery7 Traditionally patients presenting with suspected pharyngeal or oesophageal foreign bodies would receive a lateral neck and chest X-ray, and if a foreign body is identified or highly suspected, individuals would most commonly undergo a direct pharyngo-oesopharyngoscopy under a general anaesthetic.Reference Shih, Hao, Wang and Hao6 Where there is significant possibility that individuals would undergo an operation with the inherent complication risks and costs but with potential normal findings, removal under endoscopic guidance could prove advantageous.Reference Bennett, Sharma, Price and Montgomery7 Of the 52 individuals in the study by Shih et al., 16 had to proceed to rigid oesophagoscopy because of the risk of perforation, which is important to note when selecting individuals who would benefit from transnasal oesophagoscopy.Reference Shih, Hao, Wang and Hao6 No large cohort trial has been carried out looking at outcomes for transnasal oesophagoscopy versus rigid oesophagoscopy.
One of the earliest therapeutic procedures carried out via transnasal oesophagoscopy was transoesophageal puncture. Transoesophageal puncture is used for voice restoration after laryngectomy and is traditionally sited using rigid oesophagoscopy. Transnasal oesophagoscopy-guided tracheoesophageal puncture placement was first described in 2003.Reference Morrison, Chheda and Postma9 Morrison et al.Reference Morrison, Chheda and Postma9 reported that that tracheoesophageal puncture was achieved in all individuals studied who had all previously failed under rigid oesophagoscopy. This was again mirrored by the study by LeBert et al., where 38 out of 39 transnasal oesophagoscopy-guided tracheoesophageal puncture procedures were successful.Reference LeBert, McWhorter, Kunduk, Walvekar, Lewin and Hutcheson10 Although rigid oesophagoscopy is an effective method for tracheoesophageal puncture placement, exposure can be difficult in some individuals due to radiation damage or dentition. Due to the flexibility that transnasal oesophagoscopy affords, the oesophagus can be visualised during the entire procedure. In addition, transnasal oesophagoscopy has the added benefit of only requiring local anaesthesia and is therefore safe in individuals unable to undergo general anaesthesia.Reference Bach, Postma and Koufman8–Reference LeBert, McWhorter, Kunduk, Walvekar, Lewin and Hutcheson10
There have been a number of studies looking at outcomes in patients who have undergone laser surgery using transnasal oesophagoscopy, which has the advantage of increased mobility over traditional microlaryngoscopy. Transnasal oesophagoscopy-guided laser surgery was well tolerated with a favourable pain profile.Reference Halum and Moberly13,Reference Koufman, Rees, Frazier, Kilpatrick, Wright and Halum14 Although in the majority of individuals, disease can be successfully treated or controlled using transnasal oesophagoscopy-guided laser surgery, up to 30 per cent may require further treatment in the operating theatre.Reference Mohammed, Masterson and Nassif15
Oesophageal stricture can arise as a complication of head and neck surgery or can be idiopathic. The studies we reviewed where transnasal oesophagoscopy-guided dilatation was used reported a good degree of success with no major complications. However, one study reported that laryngospasm and gagging complicated the procedure resulting in the procedure being abandoned.Reference Howell, Schopper, Giliberto, Collar and Khosla16,Reference Rees, Fordham and Belafsky17 There was very little evidence on the use of transnasal oesophagoscopy during vocal cord medialisation, although, based on the authors' experience, this is possibly because of the nature of vocal cord palsy and patient compliance.
Conclusion
Endoscopes have advanced significantly in the last two decades, enabling procedures that would traditionally be carried out in the operating theatre under general anaesthesia to be done in an out-patient setting under local anaesthesia or sedation. Our review has found a lack of strong evidence for the extended role of transnasal oesophagoscopy beyond its diagnostic capabilities, particularly in guiding therapeutic procedures. However, the reported case series and the authors’ own experiences suggest that many of these interventional procedures are possible, safe and effective with minimal side effects. Hence, transnasal oesophagoscopy offers a reasonable alternative to patients who are unable to tolerate a general anaesthetic.
Competing interests
None declared
