Severe Dysphagia in a Patient with Wallenberg Syndrome and Killian Jamieson Diverticulum: A Case Report

Lateral medullary syndrome (Wallenberg syndrome) and Killian Jamieson diverticulum are both conditions known to cause dysphagia. Here, we present the first reported case of severe dysphagia due to Wallenberg syndrome and a Killian Jamieson diverticulum discovered incidentally during videofluoroscopic swallowing study. A 66-year-old male previously diagnosed with Wallenberg syndrome was referred to our hospital due to severe dysphagia. Pre-operative work-up revealed decreased left-sided pharyngeal contraction, left vocal fold paralysis, impaired laryngeal elevation, and poor upper esophageal sphincter relaxation during swallowing. Furthermore, on videofluoroscopic swallowing study, an incidental finding of a contrast-filled outpouching of the esophagus on the left, below the level of the cricopharyngeus, indicated the presence of a pharyngoesophageal diverticulum. The patient underwent bilateral cricopharyngeal myotomy with diverticulectomy, laryngeal suspension surgery, and tracheostoma revision. The diagnosis of a Killian Jamieson diverticulum was confirmed based on intra-operative findings, as the diverticular pouch was indeed seen to be located below the cricopharyngeal muscle. For patients with severe dysphagia that does not improve with swallowing rehabilitation, swallowing improvement surgery is an option. It aims to improve pre-operatively identified dysfunctional sites in the swallowing mechanism. It is important to always consider pharyngoesophageal diverticula as a possible cause of dysphagia so as not to miss the diagnosis. In this patient’s case, diverticulectomy was necessary to ensure the best possible outcomes in terms of improving his dysphagia.


Introduction
Lateral medullary syndrome (Wallenberg syndrome) and Killian Jamieson diverticulum are both conditions known to cause dysphagia.Here we present the rst reported case of severe dysphagia due to Wallenberg syndrome and a Killian Jamieson diverticulum discovered incidentally during video uoroscopic swallowing study.

Case Presentation
A 66-year-old male previously diagnosed with Wallenberg syndrome was referred to our hospital due to severe dysphagia.Pre-operative work-up revealed decreased left-sided pharyngeal contraction, left vocal fold paralysis, impaired laryngeal elevation, and poor upper esophageal sphincter relaxation during swallowing.Furthermore, on video uoroscopic swallowing study, an incidental nding of a contrast-lled outpouching of the esophagus on the left, below the level of the cricopharyngeus, indicated the presence of a pharyngoesophageal diverticulum.The patient underwent bilateral cricopharyngeal myotomy with diverticulectomy, laryngeal suspension surgery, and tracheostoma revision.The diagnosis of a Killian Jamieson diverticulum was con rmed based on intra-operative ndings, as the diverticular pouch was indeed seen to be located below the cricopharyngeal muscle.

Introduction
Lateral Medullary Syndrome, also known as Wallenberg Syndrome (WS), occurs due to occlusion of the posterior inferior cerebellar artery or vertebral artery [1,2].It manifests with a wide array of symptoms, including dysphagia, due to involvement of the nucleus ambiguus and glossopharyngeal and vagus nerves [3].
Killian-Jamieson diverticulum (KJD) is a rare type of pharyngoesophageal diverticulum that arises inferior to the cricopharyngeal (CP) muscle and lateral to the longitudinal muscle of the esophagus -an area known as the Killian-Jamieson space.It is more often diagnosed in women at a mean age of 58 years old and more commonly found on the left [4].Its pathogenesis still remains unclear, but a dyscoordination of pharyngeal and esophageal muscles together with a weakening in the musculature of the esophagus seem to play a role [4,5].Interestingly, many patients who are asymptomatic have KJD diagnosed as an incidental nding during work-up for a thyroid nodule, often seen during ultrasound [6].Compared to other types of pharyngoesophageal diverticula, KJD is four times less prevalent than Zenker's diverticula (ZD) but more common than Laimer diverticula (LD) [5].
This paper aims to present the rst report of a patient with both conditions and discuss how it was managed.

Case Presentation and Discussion
A 66-year-old male was referred to our hospital for swallowing improvement surgery to address his severe dysphagia.He was diagnosed with WS, left 1 year and 6 months prior.The patient had tracheostomy tube and percutaneous endoscopic gastrostomy (PEG) tube placement, and since then, all his nutrition was given via the PEG tube due to persistence of his severe dysphagia.The patient denied any history of dysphagia prior to being diagnosed with WS.
On physical examination, the level of the patient's larynx was noted to be low with poor elevation during swallowing.Laryngeal endoscopy showed copious pooling of secretions at the hypopharynx, left vocal fold paralysis (paramedian position xation), and weak contraction of the left hypopharyngeal wall (Fig. 1-A).A video uoroscopic swallowing study (VFSS) showed impaired ow of contrast past the area of the CP muscle with concomitant aspiration, an incidental nding of a contrast-lled outpouching of the esophagus on the left, and decreased esophageal motility (Fig. 1-B, C).High resolution manometry (HRM) showed poor contraction at the hypopharynx and inadequate relaxation at the upper esophageal sphincter (UES) during swallowing (Fig. 1-D).Neck CT scan also showed an air-lled sac lateral to the esophagus on the left at a level immediately below the cricoid cartilage (Fig. 1-E).
The planned surgery for the patient was a CP myotomy bilaterally, thyromandibular suspension, and diverticulectomy via a transcervical approach with tracheostoma revision.First, suspension laryngoscopy was done, and the diverticulum was visualized as a left lateral outpouching at the esophagus, below the CP muscle (visualized as the cricopharyngeal bar) (Fig. 2-A), con rming that it was a KJD.Once it had been visualized, a gauze strip was inserted into the diverticulum to aid in identi cation later on.The patient's neck was then opened and a previously inserted balloon catheter in the esophageal lumen was in ated.CP myotomy was done rst on the right.Next, the diverticulum on the left was carefully dissected from the surrounding soft tissues and seen to be located below the CP muscle, again con rming that it was indeed a KJD (Fig. 2-B).At this point, CP myotomy on the left was done, followed by the diverticulectomy.The excised diverticulum was noted to measure 2.5 centimeters at its widest diameter.The defect was closed with sutures in two layers.Lastly, thyromandibular suspension (Fig. 2-C) followed by tracheostoma revision was done.
Post-operative examination showed improved passage of the bolus through the UES and no evidence of the previously visualized diverticulum on VFSS (Fig. 3-A).Laryngeal endoscopy showed that the bilateral arytenoid cartilages were pulled forward due to laryngeal elevation with improved opening of the UES and decreased pooling of secretions at the hypopharynx (Fig. 3-B).HRM showed signi cantly decreased pressure at the UES during swallowing (Fig. 3-C).Post-operative histopathology results showed no malignant ndings.Post-operative swallowing training included swallowing rehabilitation, including postural adjustment, adjustment of the amount of one mouthful, and adjustment of food properties.At six months after the surgery, the patient had improved to tolerate oral intake up to level 6 of the International Dysphagia Diet Standardisation Initiative (IDDSI) Framework, which means he was able to eat soft, bit-sized foods orally [7].
The management of this patient's case was complicated due to the need to consider two conditions that are both known to cause dysphagia.Due to impairment of the glossopharyngeal and vagus nerve functions, WS can cause impairment in more than one site of the swallowing mechanism.It is known to affect the pharyngeal phase of swallowing more and manifest with laryngopharyngeal paresis [1,2,8].
The dysphagia can often be improved with swallowing rehabilitation, including direct and indirect swallowing exercises and balloon training to expand the UES.However, if the dysphagia fails to improve after several months, then swallowing improvement surgery is an option [9].
Swallowing improvement surgery addresses dysfunctional sites in the swallowing mechanism to improve the passage of food to the esophagus.In this patient's case, due to the impaired passage of food through the UES, decreased hypopharyngeal contractility, and poor laryngeal elevation during swallowing, performing a CP myotomy bilaterally together with laryngeal suspension would address these dysfunctional sites.They would serve to improve the passage of the food bolus by decreasing the resistance of the UES and increasing the length of time that food may pass through the sphincter [10,11].The displacement of the larynx anteriorly and superiorly via suspension would also help to open up the area of the UES even further [12].
Distinguishing KJD from other pharyngoesophageal diverticula pre-operatively can be a challenge.The 3 types of diverticula are differentiated based on the locations from which they arise.ZD arise from an area above the CP muscle (Killian's dehiscence), KJD arise from an area below the CP muscle (Killian-Jamieson space), while LD arise posteriorly below the CP muscle at an area called the Laimer-Haeckerman triangle [5,13].In this patient's case, the diverticulum was con rmed to be KJD intraoperatively, as the diverticular pouch was seen both endoscopically and via the open approach to be located below the CP muscle.Many patients with KJD are asymptomatic and due to its rarity and the scarce data available, there is no clearly de ned indication for surgery.Most patients who consult because they are symptomatic often have larger diverticula (median size: 2.7cm) than asymptomatic patients (median size: 1.3cm) [6]; however, most recommend surgery for all patients that are symptomatic [5], regardless of size.Furthermore, surgery eliminates the possibility of malignancy, which has been seen in 0.7-1.1% of pharyngoesophageal diverticula [14].
Another point to consider is whether the patient's WS could have caused the formation of a KJD.As previously mentioned, the pathophysiology of KJD is still unclear.CP dysfunction has been implicated in the pathophysiology of ZD [4], and inadequate relaxation of the CP muscle during swallowing was seen in this patient.However, considering that a KJD is located below the CP muscle, it seems unlikely that it formed due to the CP dysfunction seen in WS.
Lastly, it is most likely that the patient's dysphagia can mostly be attributed to his WS.However, because CP myotomy was planned bilaterally, the patient would have been more susceptible to the re ux of food material from the diverticular pouch had it not been removed.The diverticulum may have also hampered the smooth passage of food through the esophagus if not removed, making the swallowing improvement surgery less effective.This highlights the importance of thorough diagnostic work-up for all patients with dysphagia.According to literature, pre-operative VFSS has a 46% sensitivity and 97% speci city in identifying KJD speci cally [13].Considering that KJD is quite rare and not a common differential diagnosis for patients complaining of dysphagia, clinicians may miss the diagnosis of a small KJD.

Conclusion
This is the rst known reported case of a patient with both Wallenberg syndrome and a Killian-Jamieson diverticulum.In treating patients with dysphagia, thorough pre-operative work-up is essential, and physicians must always consider the possibility of a pharyngoesophageal diverticulum in order to plan the appropriate management for the best post-operative outcomes.

Declarations
Fundings: None Con icts of interest / Competing interests: On behalf of all authors, the corresponding author states that there is no con ict of interest.
Ethics: This case report was approved by the Ethics Committee of the University of Tokyo (No. 2487, 2022179NI).
Consent to participate: Written informed consent was from the patient.
Written Consent for publication: Written informed consent was obtained from the patient.and reviewed manuscript.KK contributed to patient care and reviewed manuscript.All authors reviewed and approved the nal version of the manuscript to be published.

Figures Figure 1 Pre
Figures Figure 2