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Safety and outcome using endoscopic dilatation for benign esophageal stricture without fluoroscopy.

AIM
To investigate the use of Savary-Gilliard marked dilators in tight esophageal strictures without fluoroscopy.


METHODS
Seventy-two patients with significant dysphagia from benign strictures due to a variety of causes were dilated endoscopically. Patients with achalasia, malignant lesions or external compression were excluded. The procedure consisted of two parts. First, a guide wire was placed through video endoscopy and then dilatation was performed without fluoroscopy. In general, "the rule of three" was followed. Effective treatment was defined as the ability of patients, with or without repeated dilatations, to maintain a solid or semisolid diet for more than 12 mo.


RESULTS
Six hundred and sixty two dilatations in a total of 72 patients were carried out. The success rate for placement of a guide wire was 100% and for dilatation 97%, without use of fluoroscopy, after 6 mo to 4 years of follow-up. The number of sessions per patient was between 1 and 7, with an average of 2 sessions. The ability of patients, after 1 or more sessions of dilatation, to maintain a solid or semisolid diet for more than 12 mo was obtained in 70 patients (95.8%). For very tight esophageal strictures, all patients improved clinically without complications after the endoscopic procedure without fluoroscopy, but we noted 3 failures.


CONCLUSION
Dilatation using Savary-Gilliard dilators without fluoroscopy is safe and effective in the treatment of very tight esophageal strictures if performed with care.


RESULTS:
Six hundred and sixty two dilatations in a total of 72 patients were carried out. The success rate for placement of a guide wire was 100% and for dilatation 97%, without use of fluoroscopy, after 6 mo to 4 years of follow-up. The number of sessions per patient was between 1 and 7, with an average of 2 sessions. The ability of patients, after 1 or more sessions of dilatation, to maintain a solid or semisolid diet for more than 12 mo was obtained in 70 patients (95.8%). For very tight esophageal strictures, all patients improved clinically without complications after the endoscopic procedure without fluoroscopy, but we noted 3 failures.
CONCLUSION: Dilatation using Savary-Gilliard dilators without fluoroscopy is safe and effective in the treatment of very tight esophageal strictures if performed with care.

INTRODUCTION
Esophageal strictures are a problem frequently encoun tered by gastroenterologists and can be subdivided into malignant and benign origin. Malignant esophageal stric tures are mainly caused by primary esophageal cancer but can also be caused by extra esophageal malignancies that compress the esophagus [1] .
The most common causes of benign esophageal stric tures include peptic injury, Schatzki's ring, esophageal web, radiation injury, caustic injury and anastomotic stric tures.
Upper endoscopy is the diagnostic procedure of choice for the detection of an esophageal stricture and its un derlying cause. Nevertheless, it is mandatory that biopsy samples are taken to confirm whether the stricture is be nign or malignant in nature [1] . Dilatation of esophageal strictures is a commonly per formed procedure used to relieve dysphagia due to eso phageal strictures. In clinical practice, fluoroscopy is rec ommended for monitoring the position of a guide wire and dilator [25] . Some authors, however, believe that fluo roscopy is not necessary for dilatation. The aim of this study is to describe our experience using a guide wire and marked SavaryGilliard dilators (Figure 1) without the use of fluoroscopy.

Patients
Between January 2005 and January 2011, 72 consecu tive patients (45 females, 27 males, aged 18 to 75 years old, mean age 42 years) with benign esophageal stric tures were referred to our unit for dilatation because of persistent or recurrent dysphagia. Benign stricture was ascertained using endoscopy and biopsy. There were 72 benign lesions. The diagnoses are summarized in Table 1. Patients with achalasia, malignant lesions and external compression were excluded. All our patients had vari ous degrees of dysphagia. A total of 662 dilations were performed for 72 patients who had various degrees of dysphagia prior to each session. Xray studies of the ge ography of the strictures were performed for each case before treatment.

Instruments
Examinations were performed with Olympus GIFXP or Pentax EPK700. Dilatation was performed with marked SavaryGilliard dilators.

Technique
If the stricture could be passed with a paediatric endo scope, the guide wire was placed through endoscopic guidance. Thereafter, dilatation was performed without fluoroscopy. For very tight esophageal strictures, we in serted the guide wire through the tight stricture into the esophageal lumen and SavaryGilliard dilatation was also used without fluoroscopy. In general, "the rule of threedilator size increased step by step" was carried out. If dysphagia and esophageal strictures recurred during the clinical followup after completion of a series of dila tions, additional dilatation was carried out until symptom atic relief was achieved. All procedures were performed with intravenous sedation (propofol).
Effective treatment was defined as the ability of pa tients with or without repeated dilations to maintain a solid or semisolid diet for more than 12 mo.

RESULTS
Peptic injury (Figure 2A) was the most frequent cause of esophageal benign stricture in our series in 41.6% of pa tients, followed by Plummer Vinson web ( Figure 2B) in 27.7% of cases (Table 1).
A total of 662 dilatations in 72 patients in 141 ses sions were performed. The success rate for the placement of a guide wire was 100% and for dilatation was 97%, without use of fluoroscopy, after 6 mo to 4 years of followup. We performed an endoscopy immediately for post procedure bleeding or mucosal tearing. After dilata tion, our patients are hospitalized and observed for 6 h. They are clinically examined and in a case of pain, chest Xray is carried out to check for perforation. Twenty four hours after dilatation, we phone patients to ask if there is any fever or bacteraemia. In our series, there were no adverse events or complications.
The number of sessions per patient was between 1 and 7, with an average of 2 sessions.
The ability of patients after 1 or more sessions of dilatation to maintain a solid or semisolid diet for more than 12 mo was obtained in 70 patients (95.8%).
For very tight esophageal strictures, we replaced the guide wire through the tight stricture into the lumen ini tially dilated without complications. All patients with very tight strictures had clinical improvement but we noted 3 endoscopic dilatation failures: 2 patients with anastomot ic stricture because of tumoral recurrence and 1 patient with radic stenosis; these patients underwent surgery.

DISCUSSION
Benign esophageal strictures are secondary to different causes. In our series, peptic injury was the most frequent lesions, as found in the literature [69] .
The mainstay of treatment for benign esophageal strictures is dilatation. Although dilatation usually results in symptomatic relief, recurrent strictures do occur. In order to predict which types of strictures are most likely to recur, it is important to differentiate between esopha geal strictures that are simple and those that are more complex [1,10] . Simple esophageal strictures are defined as focal and straight [1,10] . Common etiologies include pep tic injury (60%70% of cases) and a Schatzki's ring or web [10,11] . In most patients with simple esophageal stric tures, 13 dilatations are required to relieve symptoms, with an additional 25%35% of patients requiring repeat dilatations [11] . In our series, 76% of patients had simple esophageal strictures and needed from 1 to 3 sessions of dilations.
Strictures that are long (> 2 cm), tortuous or associ ated with a diameter that precludes passage of a normal diameter endoscope are defined as complex esophageal strictures [10] . The most common causes include caustic in gestion [12] , radiation injury, anastomotic stricture [13] , photo dynamic therapyrelated stricture and severe peptic injury. Complex esophageal strictures are more difficult to treat than simple esophageal strictures, require at least three dilatation sessions to relieve symptoms and are associated with high recurrence rates. If complex strictures cannot be dilated to an adequate diameter that allows passage of solid food, recur within a time interval of 24 wk or require ongoing (more than 710 sessions) dilatations, they are considered to be refractory [10] . Novel treatment modalities for refractory stricture include temporary stent placement and incisional therapy [1] . In our series, 24% were complex esophageal strictures, caused by radiation injury, caustic ingestion, anastomotic stricture and post mycosis stricture.
Successful esophageal dilatation involves both suc cessful placement of the guide wire and dilation. This study demonstrates that SavaryGilliard dilation can be successful without fluoroscopic control. There were no procedureinduced complications. All 72 unselected consecutive patients had significant dysphagia due to dif ferent types of esophageal benign pathology. Symptom relief was achieved in 69 patients. The results are similar to that reported by 3 authors [2,14,15] . However, in two stud ies, the endoscope was impassable in 5% and 29.4%. For these cases, fluoroscopy was required. During the inser tion of the wire, if there is resistance or if the patient starts coughing (which indicates that the wire is inserted into trachea through the fistula), the wire should be with drawn and reinserted. In order to prevent complications, the "rule of three" was popularized by Boyce [16] . Dilata tion should be terminated when resistance is encountered during these consecutive dilations.
The main complications associated with esophageal dilatation include perforation (can occur in 0.5% to 1.2%) [6,17] , hemorrhage and bacteremia. The reported rate of perforation and massive bleeding is 0.3%; this risk is higher when complex strictures [18] and caustic stric tures [12] are dilated. It is generally believed that the risk of perforation is minimal if the "rule of three" is applied, meaning that dilation diameters should not increase by more than 3 mm per session [10] . Predilation diameter and stricture length are established factors that influence the number of dilations required for symptom relief and the need for additional dilations [19] .
In conclusion, Adequate placement of a guide wire prior to dilation is crucial to achieve successful dilation. With the technique of TTS (through the scope) guide wire insertion, endoscopic dilatation without fluoroscopy is a safe and efficacious way to relieve dysphagia, espe cially in benign simple strictures. Repeated sessions are necessary to avoid recurrence.

Background
Esophageal strictures are a problem frequently encountered by gastroenterologists. Upper endoscopy is the diagnostic procedure of choice for the detection of an esophageal stricture and its underlying cause. Dilatation of benign esophageal strictures is a commonly performed procedure to relieve dysphagia. In clinical practice, fluoroscopy is recommended for monitoring the position of a guide wire and dilator. However, some authors believe that fluoroscopy is not necessary for dilatation.

Research frontiers
In the area of treatment of benign esophageal strictures with Savary-Gilliard dilators, the research hotspot is to describe their experience using a guide wire and marked Savary-Gilliard dilators without the use of fluoroscopy and to assess its effectiveness and safety.

Innovations and breakthroughs
In the present study, the authors performed 662 dilatations in 72 patients in 141 sessions. The success rate for placement of a guide wire was 100% and for dilatation was 97%, without use of fluoroscopy, after 6 mo to 4 years of follow-up. The authors performed an endoscopy immediately for post procedure bleeding or mucosal tearing. After dilatation, the patients of this study are hospitalized and observed for 6 h. They are clinically examined and in a case of pain, chest X-ray is carried out to check for perforation. Twenty four hours after dilatation, the authors phone patients to ask if there is any fever or bacteraemia. In their series, there were no adverse events or complications. For very tight  Figure 1 Savary-Gilliard dilatators.

B
A esophageal strictures, the authors replaced the guide wire through the tight stricture into the lumen initially dilated without complications. The ability of patients after 1 or more sessions of dilatation to maintain a solid or semisolid diet for more than 12 mo was obtained in 70 patients (95.8%). All patients with very tight strictures had clinical improvement but the authors noted 3 endoscopic dilatation failures (2 patients with anastomotic stricture and 1 patient with radic stenosis).

Applications
The study suggests that dilatation with Savary-Gilliard dilators without fluoroscopy is effective and safe in esophageal benign strictures, especially peptic injury, Plummer-Vinson web and caustic injury.

Peer review
This is a good descriptive study in which the authors report the causes of esophageal benign strictures and analyze the effectiveness and safety of Savary-Gilliard dilatation without fluoroscopy.