Swallowing Outcomes in 7 Patients Following Endoscopic Cricopharyngeal Myotomy With Primary Closure

Patient Cohort

Patient’s with symptoms suggestive of CPS or pharyngeal pouch including high dysphagia, globus pharyngeus, regurgitation, and choking episodes were prospectively identified from the outpatient clinic. Patients with suspected CPS or early pharyngeal pouch underwent flexible laryngoscopy to screen for obvious malignant or structural abnormalities contributing to dysphagia and routine barium swallow. Videofluoroscopy and esophageal manometry were not routinely performed. Patients with evidence of a prominent cricopharyngeal bar, upper esophageal dysmotility or early pharyngeal pouch on barium swallow who desired surgical intervention were consented for endoscopic CPM after discussion of risks and alternative management. All operations were performed by the same surgeon with a specialist interest in swallowing disorders at Charing Cross hospital, London.

Preoperatively, patients were asked to complete the MD Anderson Dysphagia inventory (MDADI) and Dysphagia handicap index (DHI) questionnaires. MD Anderson Dysphagia inventory contains 20 swallow-related questions scored from 1 to 5 on a Likert scale. Total points are calculated into a score out of 100 across 4 domains; global, physical, emotional and functional, with lower scores suggesting poorer swallowing outcomes. Dysphagia handicap index contains 25 questions split into 3 domains (physical, functional, and emotional) with patients ranking their symptoms from 1 (best) to 7 (worst). Scores are then totaled for each domain, with lower scores indicating a better swallow function. Patients were reviewed in the outpatient clinic at 3 months post-discharge, and were given the same swallow questionnaires. Statistical analysis comparing the median pre- and postoperative scores was performed with a Mann-Whitney U test with a result of P < .05 thought to be significant. No functional swallowing assessments were utilized in this study.

Our series contained 7 female patients with a median age of 72 years (range 52-88). Preoperative investigations diagnosed grade 1 pharyngeal pouch (3 patients), CPS (2 patients), and recurrent grade 1 pouch and CPS (1 patient each). Pharyngeal pouches were graded according to the Morton & Bailey classification system (grade 1, <2 cm; grade 2, 2-4 cm; grade 3, >4 cm). All patients described distressing dysphagia symptoms and tolerated a soft food diet only, although no patients required supportive enteral feeding. The cohort all underwent laryngo-pharyngo-esophagoscopy, injection of botox to cricopharyngeus and CPM with sutured primary closure. One patient underwent CO₂ laser myotomy due to the presence of a cardiac pacemaker with the others undergoing division via monopolar diathermy. Two patients underwent concomitant balloon dilatation of the upper esophageal sphincter.

Surgical Technique

The patient is positioned supine under general anesthesia, with neck extension facilitated via a shoulder roll and the airway secured with a reinforced microlaryngoscopy endotracheal tube. A Dedo-Pilling Laryngoscope is used to identify the vocal cords and cricopharyngeus, to distinguish the posterior laryngeal commissure from the cricopharyngeal bar. The laryngoscope is put into suspension and 90 units (3 mL) of botulinum toxin type A is then injected into cricopharyngeus at 3 different points. Balloon dilatation can then be used to dilate from 15 to 18 mm.

A diverticuloscope is then put into suspension with blades either side of the cricopharyngeal bar. The microscope is deployed to more accurately visualize the cricopharyngeus and latterly aid placement of the endoscopic sutures. A 35-watt diathermy abbey needle with suction is then used to divide the cricopharyngeal mucosa. Underlying muscle fibers are subsequently identified and divided to the level of the prevertebral fascia. Haemostasis is then achieved with 1:1000 adrenaline soaked neuropatties.

A 5-0 polydioxanone suture on a cutting needle is then used to close the mucosa with interrupted sutures, without reapproximating muscle fibers. Sutures are placed with the aid of an endoscopic laryngeal needle holder and knots are secured with a Negus knot pusher. If using a pharyngoscope with a detachable inferior blade, this can be removed to allow for more space when placing sutures. Intraoperative photographs are shown in (Figure 1).

OPEN IN VIEWER

Figure 1.

Clinical photographs showing endoscopic view of prominent cricopharyngeal bar. A, Shows the muscles fibers before division. B, Demonstrates the cricopharyngeal bar after division and reapproximation with endoscopic sutures.

A fine bore nasogastric (NG) tube is inserted at the end of the procedure under direct vision to supplement or replace oral feeding postoperatively. Postoperatively, the patient is kept nil by mouth for 2 hours and observed closely for signs or symptoms of mediastinitis. The patient is progressed onto clear fluids for the next 12 hours and oral intake can be built up onto solids the following day.

Cricopharyngeal Spasm and Myotomy

Cricopharyngeal spasm presents in elderly, comorbid patients with a spectrum of dysphagia severity. There is no agreed protocol for preoperative investigations and therefore the decision to operate is often determined by the impact quality of life, patient comorbidities, and surgeon and patient preference. Cricopharyngeal myotomy offers the only permanent improvement to dysphagia secondary to CPS and early pharyngeal pouch too small for endoscopic stapling, with video fluoroscopic studies demonstrating improved swallow through widening of the upper esophageal sphincter and reduction in the size of the pharyngeal diverticulum. ¹

Certain series comparing CPM techniques have found the endoscopic approach to be at least as effective as open surgery, and may be the favored practice due to the reduced risk of complications such as pharyngocutaneous fistula, mediastinitis, and damage to the superior laryngeal nerve.^2,5,6 However, an endoscopic approach does not entirely obviate these risks, as seen in a study of 38 open and 41 endoscopic CPM with primary closure which noted better functional outcomes in endoscopic patients, but found that significant complications including pharyngeal tear and fistula still occurred in both groups. ⁶ In a systematic review, Kocdor et al found a mean complication rate of 2% for endoscopic and 8% in open procedures across 15 studies. ² Moreover, mean success rate was higher in the endoscopic group (83% vs 68%), implying it may be a safer and more effective treatment for CPS.

Dilatation and injection of botox confer a number of advantages over myotomy, as they can be repeated if effective, and can be performed under sedation or percutaneously for those unsuitable for general anesthetic. ² However, both procedures only offer temporary improvements lasting between 0 and 24 months.^2,7 Kocdor et al noted a success rate of 78% for CPM, which was statistically significant compared to botox injection (69%) but not against dilatation (73%). However, this review is hampered by combining open and endoscopic myotomy cohorts, heterogeneous outcome measures between studies, and containing few series on dilatation, making it difficult to draw satisfactory conclusions on the various treatment’s efficacy. Nevertheless, some authors advocate a 2 stage process; wherein frailer patients are offered a dilatation as a first-line therapy in order to avoid the morbidity of a myotomy, before offering definitive surgery in those who do not benefit from conservative measures. ⁸

Primary mucosal closure has been theorized to result in improved swallowing outcomes with reduced postoperative complications by sealing the retropharyngeal defect. This is evidenced by our cohort, which has shown an improvement across all swallowing domains with no major complications occurring. Ho et al reported a significant improvement in MDADI and functional outcome swallowing scales in 7 patients undergoing primary suture closure following endoscopic CPM, ⁹ however the authors performed a more limited myotomy compared to our technique, staying within buccopharyngeal fascia and not extending to the prevertebral space. Comparable improvements following primary mucosal closure were seen by Dale et al and Lawson et al, with no case series reporting any severe complications.^10,11 This contrasts with Takes et al, who felt inflammation and scarring following CPM would close retropharyngeal defects, yet they reported free air on X-rays in 4/10 patients and surgical emphysema in 1 patient. ¹² There are notable differences in the materials used for primary closure across studies with barbed knotless ⁶ and polyglactin sutures, ⁹ u-clips, ¹⁰ and fibrin glue ¹¹ all being described with good functional outcomes and minimal complications.

There are a number of limitations to this series, with a small number of patients, short follow-up, variance in underlying pathology and surgical technique, and no comparison between patients with and without primary mucosal closure. A number of patients in this series were initially limited by pain necessitating NG feeding and several developed postoperative chest infections. Nevertheless, this may be reflective of an elderly and comorbid cohort, where a single definitive procedure may be preferable to a traumatic open operation or repeat anesthetics for temporary procedures. Finally, endoscopic placement of mucosal sutures presents a slight technical challenge, which may be heightened by anatomical issues that impede insertion of the pharyngoscope such as c-spine fixation and neck habitus.

Advantages of Surgical Technique

The modified technique described confers a significant advantage as it allows complete division of the cricopharyngeus muscle down to the level of the prevertebral fascia, without risking injury to the recurrent laryngeal nerve and inferior thyroid vessels necessary in transcervical dissections. Closure of the mucosa seals access to the retropharyngeal space, thus restoring the integrity of the pharyngeal wall and reducing the risk of surgical emphysema, deep neck space abscess, and mediastinal infections.

Although pain was a limiting factor in several of our patients, it has been hypothesized that primary closure can improve postoperative pain and therefore reduce hospital stay and reliance on NG feeding. ¹¹ Additionally, an endoscopic approach may be better tolerated in frail and elderly patients, with reduced anesthetic time and a more rapid postoperative recovery significantly reducing the risk of perioperative complications.