Esophageal diverticulum: A clinical framework for patient-tailored endoscopic management

Abstract

The management of esophageal diverticula is undergoing a paradigm shift from traditional surgery to minimally invasive endoscopic approaches. However, achieving precise treatment based on individual patient characteristics remains a significant challenge. This paper aims to establish a comprehensive clinical decision-making framework for esophageal diverticulum, encompassing diagnosis, preoperative evaluation, method selection, specific therapeutic techniques, and postoperative assessment, with the goal of facilitating precision treatment. In the preoperative evaluation section, we conduct a detailed analysis of endoscopic approach selection based on diverticulum size, anatomical location, septum length, and patient surgical history, and further discussed recent advances in endoscopic techniques. Additionally, we provide an in-depth comparison of the advantages and disadvantages of different energy modalities, devices, and therapeutic strategies, emphasizing the need for postoperative assessment to account for both technical and clinical success. Lastly, we suggest that the integration of endoscopic techniques with artificial intelligence may represent a future direction for development.

Key Words: Esophageal diverticulum; Endoscopy; Endoscopic laser diverticulotomy; Endoscopic stapler-assisted diverticulotomy; Peroral endoscopic myotomy

Core Tip: This review establishes a comprehensive decision-making framework for the endoscopic treatment of esophageal diverticula, encompassing the multi-dimensional preoperative assessment of patients, precise selection of techniques and devices, and dual evaluation of postoperative outcomes. The core perspective lies in emphasizing the formulation of individualized strategies based on diverticulum characteristics and patient conditions, assisting in achieving precision medicine in clinical practice.

INTRODUCTION

Esophageal diverticulum (ED) is a rare condition that can occur at any level of the esophagus. The exact incidence remains unclear, primarily because of the difficulty of statistical tracking, as most cases are asymptomatic[1]. Approximately 65% of patients are asymptomatic and are often discovered incidentally during examinations such as endoscopy[2]. Moreover, most cases are identified only upon the onset of symptoms, which may manifest as dysphagia, reflux, and respiratory aspiration, and may even lead to severe malnutrition[3]. This condition is predominantly an acquired lesion, primarily observed in the elderly population, with a notably higher prevalence in males aged 60-70 years. Congenital esophageal diverticula are extremely rare, occasionally seen in infants and young children, and may present as feeding difficulties or stridor[4].

A more systematic classification of esophageal diverticula can be achieved by considering multiple dimensions, including anatomical location, pathophysiological mechanisms, and histological characteristics. Based on their histological structure, they can be divided into true diverticula, which contain all layers of the esophageal wall, and false diverticula, which protrude only through the mucosa and submucosa, lacking the muscular layer[4]. Based on anatomical location, they are primarily categorized into three major types: Pharyngoesophageal, mid-esophageal, and epiphrenic diverticula[5]. Pharyngoesophageal diverticula, located near the upper esophageal sphincter (UES), are the most common type and are typically false diverticula[6]. They mainly include Zenker’s diverticulum, Killian-Jamieson diverticulum (KJD), and the rare Laimer diverticulum. Mid-esophageal diverticula are situated in the mid-esophagus, posterior to the tracheal bifurcation, and are also known as parabronchial diverticula. Epiphrenic diverticula are located in the distal esophagus above the lower esophageal sphincter (LES). Although less common, they often attract more attention because they are frequently associated with esophageal motility disorders (EMDs), which can readily lead to symptoms[7]. Based on pathophysiological mechanisms, esophageal diverticula can be classified as pulsion diverticula and traction diverticula. The majority are pulsion-type, caused by an abnormal elevation of intraluminal pressure due to motility disorders such as achalasia or Jackhammer esophagus, which forces the mucosal layer to herniate outward. A minority are traction-type, formed by pulling of the entire esophageal wall due to chronic inflammation or scar tissue in the surrounding tissues[3].

In the past, surgery was considered the preferred method for treating ED. Diverticulectomy was performed through minimally invasive thoracoscopy or open thoracotomy[2,8]. Laparoscopic surgery is also a minimally invasive and less extensive surgical option for patients with ED[9]. In recent years, non-surgical treatments such as endoscopic therapy have gradually become mainstream. The European Society of Gastrointestinal Endoscopy recommends flexible endoscopic treatment as the first-line treatment for symptomatic Zenker’s diverticulum patients of any size, rather than open surgical treatment[10]. With the rise of this trend, advanced endoscopic technologies such as endoscopic LASER diverticulotomy (ELD), endoscopic stapler-assisted diverticulotomy (ESAD), and peroral endoscopic myotomy (POEM) have emerged.

PATIENT SELECTION AND COMPREHENSIVE CONSIDERATIONS FOR PREOPERATIVE EVALUATION OF ENDOSCOPIC SURGERY

Definitive diagnosis of ED

An accurate treatment plan begins with a definitive diagnosis. Both barium meal radiography and esophagogastroduodenoscopy (EGD) can be used for the diagnosis of esophageal diverticula[5]. Among these, EGD is especially suitable for patients with complex conditions. For example, a 60-year-old patient was diagnosed not only with a large ED during gastroscopy but also with cardia relaxation, hiatal hernia, antral protrusion, and duodenal ulcer (Figure 1). Recently, studies have shown that F-fluorocholine positron emission tomography/computed tomography may also become a sensitive diagnostic method for esophageal diverticula[11].

Figure 1 The endoscopic image of patient. A: A large diverticulum of 6 cm in diameter was seen at the esophagus (30 cm from the incisors), with a large amount of food retention; B: Two polypoid-like bulges in the proximal dentate line, about 0.4-0.8 cm in size; C: The mucosa was smooth and the hernia sac was visible; D: The 0.4 cm shallow ulcer was seen on the anterior wall of the duodenal bulb.

Furthermore, high-resolution manometry (HRM), as the next step after a routine endoscopy, is particularly useful for detecting conditions that may be missed by endoscopy[12]. It plays an especially important role in differentiating epiphrenic diverticula. For example, according to the Chicago Classification (CC v3.0), the diagnosis of diffuse esophageal spasm (DES) requires ≥ 20% premature contractions with normal LES relaxation. In contrast, type III achalasia is characterized by elevated LES relaxation pressure. These two conditions are primarily and accurately distinguished through HRM[13]. This differentiation directly guides the design of the tunnel length and direction in POEM. Patients who undergo surgery with a strategy specifically tailored based on HRM findings demonstrate more significant postoperative symptomatic improvement[14]. Therefore, HRM is crucial for ensuring surgical success and preventing recurrence and should be adopted as a routine preoperative assessment for epiphrenic diverticula.

Selection of surgical approach based on characteristics of diverticula

Selection of surgical approach based on diverticulum size: Asymptomatic or small diverticula (< 1 cm) typically do not require intervention, and regular follow-up observation is recommended. For patients with symptoms or diverticula with a diameter ≥ 3 cm, active intervention is necessary due to the potential for severe complications such as reflux, recurrent aspiration pneumonia, and even malignant transformation[15]. The management of medium-sized diverticula (1-3 cm) requires comprehensive judgment based on a synthesis of symptoms and location[16]. It must be emphasized that after a definitive diagnosis of ED, individualized treatment is paramount. This necessitates a careful consideration of multiple factors, including diverticulum characteristics, symptom severity, comorbidities, the patient’s surgical history, spinal condition, and surgical tolerance.

Selection of surgical approach based on diverticulum location: (1) Pharyngoesophageal Diverticula: Diverticula in this region must be clearly distinguished between Zenker’s diverticulum and KJD, as their treatment strategies differ significantly. Zenker’s diverticulum is located in the Killian’s triangle and is closely associated with dysfunction of the UES. The preferred treatment is endoscopic diverticulotomy (e.g., Z-POEM) to relieve UES obstruction[17]. However, although Z-POEM is a safe and effective treatment for Zenker’s diverticulum, approximately 20% of patients may still require reintervention in the short term due to symptom recurrence[18]. For cases requiring reintervention, flexible endoscopic diverticulotomy is more suitable[5]. In contrast, KJD is situated below the cricopharyngeus muscle on the left lateral wall of the esophagus, an anatomical location adjacent to the recurrent laryngeal nerve. Management typically involves diverticulectomy alone, without myotomy of the cricopharyngeus or esophageal muscle layers, as performed for Zenker’s diverticulum, to avoid nerve injury[19]. Therefore, an accurate diagnosis that distinguishes Zenker’s diverticulum from KJD is crucial. For KJD, preoperative endoscopic observation of the palisade vessels at the pharyngoesophageal junction can aid in more precise localization, while intraoperative endoscopic guidance can effectively enhance procedural safety[20]; (2) Mid-esophageal diverticula: Mid-esophageal diverticula are relatively rare in clinical practice. Thus, the therapeutic strategy should be determined based on a comprehensive evaluation of the diverticulum size, the presence of motility disorders, and complications (e.g., bronchoesophageal fistula). Generally, myotomy should not be performed in the absence of a motility disorder. If a motility disorder is present, an extended myotomy including the LES should be performed[21]; and (3) Epiphrenic diverticula: Since epiphrenic diverticula are frequently associated with LES dysfunction, the core principle of treatment is relieving distal obstruction, which often necessitates myotomy. Consequently, the decision regarding diverticulectomy and the specific approach to myotomy should be individualized based on the diverticulum’s location and associated conditions. For instance, for a diverticulum located on the ventral side, care must be taken to preserve a bridge of muscle tissue between the longitudinal incision line of the diverticulectomy and the myotomy site[22]. Among minimally invasive alternatives, POEM can be performed alone to alleviate symptoms of the motility disorder without direct resection of the diverticulum[23]. If the diverticulum enlarges after POEM or in cases of severe symptoms, diverticulectomy can be performed as a salvage procedure[24].

The impact of septum length on the successful implementation of endoscopic diverticulectomy: The length of the septum directly affects the complexity of the surgical procedure and the technical success rate. For example, in the case of Zenker’s diverticulum, when the average septum length is 33.7 ± 11.04 mm, the technical success rate can reach 100%[25]. However, if the septum is too long, additional endoscopic septotomy may be required to alleviate symptoms fully, and this may increase the risk of residual postoperative symptoms. For long septa, the complete division of the septum is crucial for clinical success, and diverticula with a septum length > 4 cm may require multiple endoscopic interventions[26].

Selection of surgical approach based on EMDs

Since the reported correlation between EMDs and formation of pulsion diverticula, EMDs include Zenker’s diverticulum (closely associated with UES dysfunction), achalasia, and other functional conditions[27]. Not only do they directly affect the severity of a patient’s symptoms, such as dysphagia, but they also play a key role in the success and efficacy of endoscopic procedures. Thus, understanding the characteristics of motility disorders is fundamental to developing surgical strategies.

For patients with coexisting achalasia, POEM has become the preferred surgical approach[28], with type II achalasia showing the best therapeutic outcomes[29]. Studies have also shown that POEM significantly alleviates dysphagia (with a notable reduction in Eckardt scores)[30]. However, when used in the treatment of EMDs, it is associated with a relatively higher incidence of postoperative reflux[31].

For spastic disorders of the esophageal body (such as DES), if LES function is normal, LES-sparing POEM is applicable. This approach effectively relieves symptoms while significantly reducing the risk of postoperative reflux[32]. Therefore, the type and severity of motility disorders diagnosed preoperatively directly determine the site and extent of myotomy, the selection of endoscopic techniques, and predict both the symptomatic relief rate and the risk of postoperative reflux.

Selection of surgical approach based on prior surgical interventions

Anatomical changes: Patients who have undergone conventional surgery may have scarring or anatomical changes that make endoscopic procedures more difficult, such as a limited intraoperative visual field and an increased risk of perforation[33]. For example, in patients with Zenker’s diverticulum who have undergone prior open surgery, endoscopic procedures require more precise techniques for separation and incision. The use of endoscopic surgery in patients with prior surgical interventions has shown lower rates of recurrence and postoperative complications.

Surgical mapping and decision pathway: For patients with a history of surgery, the choice of endoscopic treatment should be tailored to their specific medical history. Specifically, a new surgical approach should be employed to bypass scar tissue according to the patients’ previous surgical history.

For instance, after a failed Heller myotomy, dense fibrosis and scarring in the original incision area necessitate the reconstruction of a tunnel on the anterior wall to safely complete the myotomy during POEM[34]. In cases of pseudoachalasia following gastric bypass surgery, a detour POEM can only be performed in the excluded gastric cavity to reach the new high-pressure zone[35]. For recurrent Zenker’s diverticulum following open surgery, due to extensive scarring in the posterior pharyngeal wall, myotomy is no longer performed. Instead, flexible endoscopic septal division is used to directly cut the diverticular septum, thereby relieving the obstruction[35].

Overall, those with prior surgical interventions who undergo endoscopic surgery often tend to choose endoscopic treatment[36]. However, this requires a clear understanding of the prior surgical approach during preoperative planning to accurately determine the entry point, direction, and scope of the procedure.

Selection of surgical technique based on spinal conditions

Preoperative examinations should accurately identify spinal abnormalities, such as scoliosis. This is particularly critical in endoscopic procedures involving the cervical region (e.g., endoscopic diverticulotomy for Zenker’s diverticulum). Such abnormalities may complicate the access route during endoscopic diverticulotomy and increase the risk of esophageal perforation, residual diverticulum, or recurrence[37,38]. Therefore, preoperative assessments, including patient-specific 3D-printed models for surgical simulation, should be employed to rule out or confirm relevant spinal issues. This aids in deciding whether alternative approaches or additional preventive measures are necessary.

OVERVIEW OF ENDOSCOPIC TREATMENT TECHNIQUES

ELD and ESAD

ELD uses a laser to cut the tissue around the diverticulum, reducing the size of the diverticulum[39]. Importantly, a laser can precisely cut tissue, reducing the risk of bleeding and damage to surrounding healthy tissue. ESAD uses endoscopy and a special stapler to remove the tissue around the diverticulum and close the incision with staples. This method may also be quicker and more direct compared to ELD. Both ELD and ESAD are safe techniques, with intraoperative adverse events mainly including esophageal or diverticular perforation, mediastinitis, and cervical emphysema[40]. Both are commonly used for Zenker’s diverticulum[41,42], among which ESAD may apply to ED complicated with superficial esophageal cancer[43]. A meta-analysis suggests[44] that the two methods seem similar in terms of adverse events and efficacy, and the preferences and experience of the surgeon can guide the choice of procedure. Generally, the early systemic inflammatory response after ESAD is significantly lower than after ELD[45], but with a higher risk of recurrence; ELD has slightly higher risks but lower short-term recurrence rates, making it very suitable for most revision cases[46].

As devices and technology continue to advance, there have been varying degrees of progress in ELD and ESAD. ELD commonly uses carbon dioxide laser assistance, but recent reports[47] have suggested the potential use of a pulsed Holmium laser (PHL). Compared to carbon dioxide lasers, PHL offers the advantage of a shorter wavelength, resulting in shorter tissue penetration time and cleaner incisions[48]. The use of PHL also appears to reduce the incidence of intraoperative adverse events and the recurrence rate[47]. Additionally, a potassium titanyl phosphate laser is a more cost-effective alternative to carbon dioxide lasers[49]. Research by Koch et al[50] indicates that using collagen fiber-sealing material patches to cover the base wound after ELD surgery can enhance ELD safety without affecting its success rate.

POEM

POEM involves inserting an endoscope through the mouth and advancing it between the mucosal and muscular layers of the esophagus to alleviate symptoms caused by esophageal muscle spasms or other diseases. Yang et al[51] conducted a retrospective study to explore the application of POEM technology in treating esophageal disorders and provided specific endoscopic images during the treatment. The surgical outcomes indicated that POEM did not pose any technical difficulties in clinical practice. POEM is a relatively safe technique, with intraoperative adverse events mainly including mucosal perforation, pneumothorax, pneumoperitoneum, mediastinal emphysema, subcutaneous emphysema, pleural effusion, and pneumonia[52]. Regarding the mid- to long-term outcomes of POEM, Ren et al[53] conducted a multicenter cohort study with a minimum follow-up of 3 years. The average Eckardt score preoperatively was 8.59, which significantly improved to 2.21 at 36 months postoperatively, with clinical success in 30 of 34 cases and no long-term adverse events. POEM demonstrates good therapeutic effects for various sizes of Zenker’s diverticulum[54]. Ward et al[55] conducted a retrospective multicenter study and found that POEM treatment is also highly effective for elderly individuals.

SELECTION AND COMPARISON OF ENDOSCOPIC SURGICAL INSTRUMENTS AND ENERGY SOURCES

Comparison of flexible vs rigid endoscopes

Recent research on flexible endoscopy has been very active across ELD, ESAD, and POEM. Flexible endoscopic septum division (FESD) involves using a flexible endoscope to perform septal myotomy. The goal of treatment is to reduce the size of the diverticulum and improve pharyngeal motor function, thereby improving the symptoms of dysphagia and regurgitation[56]. Rigid endoscopic treatment methods require general anesthesia. However, flexible endoscopic treatment can be performed without anesthesia[57]. Moreover, retrospective cohort studies have demonstrated that flexible endoscopy is associated with the shortest operative time, which is more favorable for the repair of Zenker’s diverticulum and reduces the probability of adverse events[58]. Although the recurrence rate of flexible endoscopy (29%) is slightly higher than that of rigid endoscopy (26%), there is no significant difference[59]. Therefore, reducing the surgical recurrence rate is crucial for promoting the adoption of both endoscopic approaches.

It is difficult to determine the boundaries of the upper esophageal muscle, and excessive cutting can lead to complications, leading doctors to retain part of the septum to avoid risks. However, Costamagna et al[60] found that the success of flexible endoscopic treatment is related to the length of septal incision. Therefore, Wilmsen et al[61] used a 5 mm fully rotatable surgical stapler (MicroCutter 30 Xchange, Cardica Inc.) inserted next to the ultra-thin flexible endoscope to treat Zenker’s diverticulum, which can completely dissect the septum and also accommodate the closure of the tip.

Comparison of endoscopic vs laparoscopic/robotic interventions

Clarifying the respective indications for endoscopic and minimally invasive surgical procedures is crucial for optimizing treatment decisions for esophageal diverticula.

Efficacy vs results: POEM significantly improves dysphagia symptoms, and long-term efficacy is comparable to laparoscopic Heller myotomy[62]. Endoscopic techniques are associated with a short hospital stay and quick postoperative recovery, making them the first choice for frail or elderly patients.

Laparoscopic surgery is indicated for patients with larger diverticula or those requiring complex anatomical reconstruction[63,64]. Moreover, robotic surgery offers greater operational precision, but it is expensive and has a slightly longer recovery period.

Complication analysis: Common endoscopic surgery complications include perforation, pneumothorax, and subcutaneous emphysema, but the incidence is low (< 5%)[65].

Postoperative complications of laparoscopic and robotic surgeries include infections and fistula formation. There is also an objectively higher likelihood of developing GERD[66], indicating relatively elevated risks, particularly in complex procedures.

Risk/benefit analysis: Endoscopic surgery is less invasive and less costly, making it more suitable for patients with mild to moderate disease or for treating a single diverticulum.

Laparoscopic and robotic surgeries are preferred for complex cases. Among these, in the research on minimally invasive esophagectomy for esophageal cancer, robotic surgery is associated with fewer postoperative complications but higher costs. The choice of surgical approach thus involves a trade-off between increased expense and higher risks[67].

Comparison of CO₂ laser vs PHL

In the endoscopic treatment of esophageal diverticula and motility disorders, CO₂ lasers and PHLs exhibit similar yet slightly distinct physical properties, resulting in marginally different clinical outcomes. However, studies directly comparing these two modalities remain extremely limited. The CO₂ laser is highly absorbed by intracellular water[68], enabling extremely precise cutting with predictable penetration depth[69], which is particularly suitable for anatomical regions requiring utmost precision.

The PHL also uses water as its primary absorber[70] and operates in a pulsed mode[47]. Its cutting mechanism combines thermal and mechanical cavitation effects and also has a high coefficient of absorption in water, leading to great tissue ablation efficacy and cutting ability[71].

In endoscopic applications, laser technologies such as CO₂ lasers and PHLs have demonstrated excellent safety profiles. The CO₂ laser, with its high cutting precision and minimal thermal damage, has become the preferred choice for treating conditions such as Zenker’s diverticulum[72]. In recent years, the PHL also has been a safe and effective treatment for Zenker’s diverticulum[47]. This is attributed to its excellent hemostatic capability and ability to manage larger diverticula[73,74], as well as its shorter wavelength, which enables more precise, cleaner cutting than the carbon dioxide laser[47]. Overall, the combination of laser technology and endoscopic surgery not only reduces postoperative recurrence rates, particularly in complex cases, but also significantly decreases intraoperative blood loss and minimizes damage to adjacent healthy tissues, thereby further enhancing patient safety and intraoperative comfort[47,72]. Furthermore, for those seeking to balance high precision and strong coagulation ability, the 445 nm blue laser can be considered. It is a promising alternative in endoscopic surgery for Zenker’s diverticulum, though further long-term studies in other segmental diverticula are still needed[75].

Comparison of laser technology vs stapler resection

Clinical efficacy: (1) Reduction in diverticulum size: The CO₂ laser group demonstrated a significantly greater reduction in Zenker’s diverticula size than the stapler group. However, there were no statistically significant differences in symptom scores (EAT-10) or swallowing function (PAS/PCR) between the two groups[76]; and (2) Recurrence rate: The clinical long-term recurrence rate was higher in the laser group (51%) than in the stapler group (37%). But the difference did not reach statistical significance[77]. Similarly, no statistically significant difference was observed in the risk of requiring reoperation[44].

Safety: (1) Visualization quality: Laser technology provides a clearer surgical field during endoscopic procedures by avoiding visual obstruction, thereby facilitating maneuverability. It minimizes thermal conduction damage, thereby collectively reducing the risk of injury to deeper fascial layers[75]; (2) Complications: No significant differences were observed between the two groups in terms of esophageal perforation, postoperative dysphagia, or major complications such as bleeding and infection[44]; and (3) Quality of life: Patients in the laser group reported higher subjective scores for symptom improvement and better postoperative quality of life[78].

The technical points, indications, advantages and disadvantages of endoscopic treatment for ED have been summarized (Table 1).

Table 1 Endoscopic techniques for esophageal diverticulum: Technical essentials, indications, advantages and drawbacks.

Technique name	Core technology	Best indications	Advantages	Limitations/common complications
FESD	Uses flexible endoscope and electrocautery or laser to cut the diverticular septum	Zenker's diverticulum and Killian-Jamieson diverticulum, especially for relieving symptoms requiring repeated surgery and recurrent Zenker's diverticulum after open surgery	No need for anesthesia, minimal trauma	Relatively high recurrence rate compared to open surgery
POEM	Establishes a submucosal tunnel and cuts the muscle layer	Zenker's diverticulum (Z-POEM), especially in patients with esophageal motility disorders	Significant relief of dysphagia symptoms, short hospital stay, quick postoperative recovery, preferred method for elderly and frail patients	High incidence of postoperative reflux esophagitis, especially in patients with hiatal hernia
ESAD	Uses endoscopy and a special stapler to complete cutting and suturing in one step	Zenker's diverticulum, may also be suitable for esophageal diverticulum combined with superficial esophageal cancer	Fast operation, relatively low early systemic inflammatory response compared to laser group	Higher recurrence risk compared to laser group
ELD	Uses CO2/Holmium laser for precise vaporization and cutting of the septum	Zenker's diverticulum, especially recurrent, fibrotic, or anatomically complex cases	Excellent surgical field, short operation time, good intraoperative hemostasis, allows for greater reduction of the diverticulum, high cutting precision, low risk of damage to deeper fascial layers, high patient comfort during surgery, improved postoperative quality of life, suitable for most revision cases	Possibly higher long-term recurrence rate

FESD: Flexible endoscopic septal diverticulotomy; POEM: Peroral endoscopic myotomy; ESAD: Endoscopic stapler-assisted diverticulotomy; ELD: Endoscopic laser diverticulotomy.

POSTOPERATIVE ASSESSMENT AND CLINICAL OUTCOME ANALYSIS IN ENDOSCOPIC SURGERY

In the management of esophageal diverticula (e.g., POEM, FESD, or surgery), technical success is the foundation, while clinical success is the ultimate goal. Technical success is a prerequisite for clinical success, but only reflects the feasibility of the procedure, not symptom improvement. Clinical success, on the other hand, requires a combination of subjective patient feedback and objective indicators that reflect the treatment’s actual benefits. Postoperative evaluation should consider both aspects.

Technical success

Technical success primarily focuses on the quality and safety of the surgical or endoscopic procedure, including whether it was completed, the incidence of complications, and technical parameters. For instance, whether the endoscope can successfully pass through the narrowed area[79] and complete the targeted operation as planned[80], etc. The relevant measurement parameters include technical success rate and procedure completion rate[81]. Additionally, a low intraoperative complication rate is also a measure of technical success[82].

Clinical success

Clinical success is primarily evaluated based on the extent of symptom relief and improvement in quality of life. This is typically measured using standardized questionnaires, scoring systems, and changes in symptom severity. Below are common metrics categorized and described as follows:

Dysphagia scoring: Dakkak and Bennett Dysphagia Score (DB score) is one of the most frequently used indicators of clinical success. For example, it can be used to quantitatively assess the severity of dysphagia in patients with Zenker’s diverticulum. A post-treatment DB score ≤ 1, without the need for secondary intervention, is considered a primary or core criterion for judging treatment success in many studies. Conversely, higher scores indicate more severe dysphagia[83].

Overall symptom improvement and recurrence rate: This includes the degree and duration of symptom relief (e.g., dysphagia, reflux) and recurrence-free status. Recurrence is defined as an increase in postoperative scores (e.g., elevated dysphagia score one month after surgery)[84].

Quality of life questionnaires: These tools assess changes in swallowing function and quality of life, quantifying patient comfort and daily functioning[78]. Notably, the integration of robotic and endoscopic techniques has the potential to achieve nearly 100% clinical success, representing a promising direction for future development[85].

The clinical decision-making framework for esophageal diverticula mentioned above has been organized (Figure 2).

Figure 2 Algorithm for the endoscopic management of esophageal diverticula. EGD: Esophagogastroduodenoscopy; PET/CT: Positron emission tomography/computed tomography; POEM: Peroral endoscopic myotomy; LES-POEM: Lower esophageal sphincter-sparing peroral endoscopic myotomy.

CONCLUSION

As a safe and effective technique, the future development of endoscopic treatment requires improved surgical accuracy, which is inseparable from preoperative preparation and surgical equipment. During pre-treatment, doctors can customize surgical methods for patients using HRM, thereby improving surgical outcomes with effective data[86]. The continuous innovation and development of surgical equipment have led to significant progress in endoscopic treatment. From rigid to flexible endoscopes, from the needle-knife papillotome to various new devices, and from carbon dioxide lasers to PHL, advances in surgical equipment have led to improved patient outcomes. The development of intraoperative auxiliary equipment also reflects the refinement of surgeons’ skills, such as the use of the functional Visitor Imaging Probe to guide myotomy under endoscopy, thereby improving clinical success rates and reducing postoperative symptoms[87]. Furthermore, treatment outcomes depend not only on the technique itself but also on the diverticulum size, the patient’s anatomical characteristics, and the surgeon’s experience[88].

The step-by-step development of endoscopic therapy technology brings good news to patients. With the introduction of sophisticated equipment, endoscopic therapy is increasingly meeting individual patient needs. However, as personalized medicine advances, new challenges continue to arise - processing large amounts of data makes patterns harder to discern. The main theme of technological development in the 21^st century is artificial intelligence. Considering the intelligence of endoscopic therapy might be a way out.