Esophagus is commonly known as the food pipe or the gullet. It is an organ in tube form, through which the food passes from the pharynx to the stomach. It is 28 cm long and 2 cm in diameter. The esophagus is not a hollow tube. It is a fibromuscular tube, made up of muscles, that contract to move the food to the stomach. This process is called as peristalsis. At the top of esophagus is a band of muscle called the upper esophageal sphincter and another band of muscles called the lower esophageal sphincter is placed slightly above the stomach. Schatzki ring or esophageal ring is condition of the esophagus when the ring narrows down due to changes in muscular tissue of the esophagus.
Schatzki Ring or Esophageal Ring: An Overview
Among different types of esophageal diseases observed, there is a medical condition known as Schatzki's ring or Esophageal ring. It was first described by Dr. Richard Schatzki and hence it is also named after him. Esophageal ring is a condition of narrowing of the lower part of the food pipe or esophagus caused by the changes in the esophageal mucosal or muscular tissue. This narrowing or stricture is a ring shaped structure, which causes difficulty in swallowing (dysphagia). Schatzki ring or esophageal ring are further subdivided into the ones found above the esophagus/stomach junction and are called A rings and those found at the lower esophagus as B rings. The B rings are the most common type of Schatzki ring or esophageal ring.
Symptoms of Schatzki Ring or Esophageal Ring
In majority of cases, Schatzki ring or esophageal ring does not show any symptoms, hence the person suffering from it does not realize that they have Schatzki's ring. When Schatzki ring or esophageal rings are of 13 millimetres in diameter or narrower they cause the following symptoms:
- Intermittent difficulty in swallowing solid food is common. While less occasionally there is obstruction to the liquid diet.
- The poorly chewed food gets obstructed at the Schatzki ring or esophageal ring before reaching the stomach.
- Patients suffering from Schatzki ring or esophageal ring can present with severe chest pain due to the obstruction caused to the bolus of food.
- Completely blocked esophagus, which causes food impaction.
- In more severe cases, food and/or liquids get stuck and coughing may begin.
- The patients suffering from Schatzki ring or esophageal ring need to regurgitate the undigested food to feel better.
- Weight loss due to problems in consuming foods is common.
Epidemiology of Schatzki Ring or Esophageal Ring
Approximately 6% to 14% of patients who receive routine barium swallow test of the esophagus are found to have a Schatzki ring (distal ring). However, 5–15% of patients who undergo barium esophagram to diagnose the cause of dysphagia were seen to have esophageal webs or proximal rings. The lower esophageal rings appear to be more common than upper esophageal webs.
Although, it wasn't found to be more in any particular age group, most patients diagnosed with Schatzki ring or esophageal ring were above 40 years. It is relatively rare in children. Schatzki ring or esophageal ring occurs in both males and females equally.
Causes of Schatzki Ring or Esophageal Ring
The following are causes and risk factors of Schatzki's ring or esophageal ring:
- Genetic defect from the birth.
- Gastro Esophageal Reflux Disease (GERD) can lead to Schatzki ring or esophageal ring. The narrowing of esophagus is caused by the acid from the stomach entering the esophagus. It leads to tissue scar, which causes stricture of esophagus leading to esophageal ring formation.
- Hiatal hernias.
Pathophysiology of Schatzki Ring or Esophageal Ring
The pathogenesis of Schatzki ring or esophageal ring is not clear. There are hypotheses, which have been put forth as follows:
- The Schatzki ring or esophageal ring is a layered collection of redundant mucosa which forms when due to unknown reasons the esophagus shortens transiently or permanently.
- The Schatzki ring or esophageal ring is congenital in origin.
- The ring is actually a short stricture which occurs as a result of gastroesophageal reflux disease. This appears as a protective barrier to prevent damage due to further reflux.
- The Schatzki ring or esophageal ring is a consequence of pill-induced esophagitis.
More preference is given to the third hypothesis although still enough data is yet to be collected to prove it.
Complications of Schatzki ring or esophageal ring
The major complication noticed is in the form of severe chest pain in the patients due to the obstruction caused during passage of the bolus of the food.
Diagnosis of Schatzki Ring or Esophageal Ring
Proper clinical evaluation of dysphagia requires a detailed history. A Schatzki ring or esophageal ring is often diagnosed by an esophagogastroduodenoscopy or with barium swallow. Endoscopies and barium swallow often reveal unsuspected Schatzki rings or esophageal rings in case of asymptomatic patients.
- Endoscopy involves use of a flexible view tube, which is put in through the mouth to the esophagus under intravenous sedation. It shows a ring within lumen of the esophagus. The ring is generally located only a few centimetres above the gastro-esophageal junction where the esophagus joins the stomach. These rings can also appear as esophageal web which do not cover the esophagus completely.
- The barium swallow tests involves taking in the barium tablet or barium soaked food bolus and using radiological techniques to produce barium esophagram.
All these studies show narrowing at the end of the esophagus and the presence of a hiatal hernia. These tests also help to rule out other problems of esophagus.
Treatment of Schatzki ring or esophageal ring
The treatment of Schatzki ring or esophageal ring consists of medications and endoscopy.
The doctor prescribes medications such as potent antisecretory agents as, proton pump inhibitor (PPI) to reduce the reflux of the stomach acids into the esophagus to decrease the scarring or narrowing. These agents inhibits the H+/K+ -ATPase enzyme system in the gastric parietal cells, resulting in decreased gastric acid secretion.
In case of complete obstruction of the esophagus, it leads to severe chest pain and an immediate treatment needs to be done with endoscopy. A specialized fibre-optic camera is used to remove the lodged food. After obstruction is located, forceps or snares are used to remove the food out of the esophagus or push it into the stomach.
- The doctor also uses endoscopy and performs esophageal dilation (stretching) or breaks the ring up. Large-bore endoscopic dilation is the mainstay of therapy for both upper and lower esophageal lesions. It is frequently performed with either Savary or Maloney or balloon dilators.
- Esophageal dilation might require to be repeated in case of recurrence of narrowing and/or symptoms over time.
- If dysphagia persists or recurs after dilation, one should consider esophageal manometry to diagnose any treatable motility disorder.
- For treatment of Schatzki rings or esophageal rings, electrocautery and surgical resection are performed along with steroid injections in the lesion. These techniques are also used in refractory cases following unsuccessful dilation.
- In patients with GERD, an anti-reflux procedure such as anti-reflux surgery is necessary to prevent reflux and repair the hiatal hernia. The procedure is performed using minimal invasive approach called Laproscopic Nissen Fundoplication.
Prevention of Schatzki Ring or Esophageal Ring
Schatzki ring or esophageal ring cannot be prevented. However, its symptoms can be reduced by approaching the physician as early as possible when noticed by the patients.
- Schatzki ring or esophageal ring patients should thoroughly chew the food to avoid obstruction to the food during its passage through the esophagus.
- To prevent the reoccurrence, a good control of the GERD through change in habits and use of proton pump inhibitors is essential.
Diet for Schatzki Ring or Esophageal Ring
Liquid diet is most effective after any procedure done to correct Schatzki ring or esophageal ring. The patients should go for the dietary modification such that the food should be chewed as thoroughly as possible and should not eat it quickly. This is especially in case of meat and bread products. They should also eat less oily and spicy foods to prevent excess acid formation. Citric fruits should also be taken cautiously.
Schatzki ring or esophageal ring occurs in few patients and is usually caused due to GERD. If untreated the ring will increase in size and will cause severe chest pain due to obstruction to the passage of the food through the esophagus. The best treatment strategy is the endoscopy method which dilates the esophagus. This should be further treated with proton pump based medications; while the refractory cases of Schatzki ring or esophageal ring following unsuccessful dilation should be treated with electrocautery and surgical resection. With diet and lifestyle modification, one can manage this condition and prevent recurrence.