Benign esophageal strictures are a common cause for dysphagia. The causes of these benign strictures may include peptic, corrosive, anastomotic or post radiation therapy. Peptic strictures are the most common cause in the Western population whereas in India corrosive strictures are more frequently encountered. Endoscopic dilatation of these strictures with plastic bougies or balloons is the mainstay of treatment. Successful dilation coupled with adequate treatment of the cause when possible, relieves the patient of dysphagia and thus surgery can be avoided. End point of successful dilation is usually to reach diameter of 15 mm, where patients do not have symptoms of dysphagia. Long term results are measured by recurrence, which is defined by recurrence of the symptoms. Certain tips and tricks for esophageal stricture dilatation are outlined below.
Tip 1: Assess stricture characteristics adequately prior to dilatation
Stricture characteristics like location (upper/middle third or lower end, length of the stricture (focal vs long segment), central or eccentic and number of strictures must be assessed before starting dilatation. Especially corrosive strictures are multiple, long and eccentric. Best way to assess these strictures is by a barium contrast study. Prior evaluation of these characteristics may have bearing on planning of endoscopic dilation (for example: focal lower end peptic strictures can be managed by balloon dilatation whereas long segment corrosive strictures are better managed by bougie dilators).
Tip 2: Avoid dilation when deep ulcers are present at the stricture site
Deep ulcers may be present at the stricture site due to the primary etiology (example – Peptic ulcers in peptic strictures, corrosive injury). Dilation should be avoided in the presence of deep ulcers to avoid risks of esophageal perforation at the stricture site. Etiological treatment, when possible may help heal the ulcers and then make the stricture amenable to dilation.
Tip 3: Make sure the wire is correctly placed
It is important to make sure that the wire is well placed in the stomach to avoid risk of esophageal injury. When the scope is negotiable across the stricture, the tip of the wire should be well placed in the gastric antrum. In this regard when a standard UGI endoscope is non negotiable, a pediatric UGI endoscope may be used to traverse the stricture and place the wire appropriately under direct vision. If the scope can’t be negotiated across the stricture, fluoroscopy should be used to place the guide wire well below the diaphragm.
Tip 4: Select the right dilator
Focal strictures (<2 cm) at the lower end are better dilated using balloon dilators but longer strictures or upper/middle third strictures are better dilated using the wire – guided bougie dilators. Bougie dilators are Wire-guided plastic dilators and are flexible, tapered, polyvinyl chloride, latex-free cylindrical solid tubes with a central channel to accommodate a guidewire. Savary-Gilliard dilators (Cook Medical, Winston-Salem, NC) have a long tapered tip and a radiopaque marking at the base of the taper designating the point of maximal dilating caliber.
Tip 5: Ensure successful dilation
Symptomatic relief can be offered to patients only if the dilatation is successful. During balloon dilation, it is essential to hold the inflated balloon at the stricture site for atleast 60 seconds. In case of bougie dilators it is essential to ensure that the widest part crosses the site of the stricture. This can be ensured on fluoroscopy as the widest part of the bougie dilators (Ex: Savary – Gilliard dilators) are marked with a radiopaque marking at the base of the taper designating the point of maximal dilating caliber. Alternatively, the location of the stricture from the incisors can be noted on prior endoscopy and the bougie should be inserted beyond that based on the markings on the dilators. Make sure that dilator slides over the guide wire, rather than pushing the guidewire and dilator simultaneously, as that can cause a loop in throat.
Tip 6: Limit dilation to severe resistance in each session
The ‘rule of three’ is enshrined in the protocol for dilation. It states that endoscopic dilation should be limited to three increments in dilator diameter and one should not rush to dilate further. It seems to be a reasonable guideline especially for beginners, but should not be set in stone. The limit of dilation should be guided by the resistance felt to dilation and can be decided on a case to case basis .The subsequent dilation could be planned after a duration of one week till we reach the maximum diameter which would allow the mucosal breaks to heal and reduce risks of perforation. Balloon dilation is not guided by these factors as the endoscopist cannot feel the resistance and pre determined amounts of balloon inflation should be used.
Tip 7: Refractory strictures :Intramucosal injection at the stricture site
Refractory esophageal strictures are the ones, which require more than five sessions of dilatation at 2 weeks interval to achieve a diameter of 14 mm in the absence of endoscopic evidence of inflammation. The most frequent cause of failure of dilation is fibrosis and re-healing after stricture dilation. Injection of aliquots of steroids like triamcilone acetonide at the stricture site may prolong time to re-healing and fibrosis. Intralesional injections of triamcinolone acetonide (40 mg/mL diluted 1:1 with saline solution) should be injected by using a 23-gauge, 5-mm long sclerotherapy needle in aliquots of 0.5 mL. At each session, 4 injections (4 quadrants) are made at the proximal margin of the stricture with another 4 injections into the strictured segment itself whenever possible. Patients who receive steroid injections at the stricture have been shown to require fewer dilations to prevent dysphagia. Mitomycin C is chemotherapeutic agent with antifibrotic effects. It is alternative agent to help reduce the number of serial dilations
Tip 8: Inject and then dilate
We prefer to give steroid or mitomycin C injections at the stricture prior to dilation. Following dilation the view of the stricture is obscured due the blood and injection may become technically difficult. Injection into the dilated portion of the stricture may be done following stricture dilation.
Tip 9: Post procedure: Look for complications
Most are done under IV sedation or propofol with analgesia as an out patient procedure and therefore early symptoms related to esophageal leak may not be present. Feeling the neck for crepitus is a easy way to assess any evidence of a leak. In case the patient complaints of severe pain following dilation, it is always prudent to get a chest X ray before sending the patient home. Post dilation patient may be prescribed analgesics for a day in case of pain. Medical treatment of strictures need to continue during the interval between dilations (Ex : Proton pump inhibotors for peptic strictures).