Esophageal diverticula are blind pockets covered with epithelium attached to the lumen of the esophagus. There are 3 favorable sites: ① pharyngoesophageal diverticulum; it occurs at the junction of pharynx and esophagus, and is an expansile diverticulum; ② parabronchial diverticulum; it occurs in the middle part of the esophagus, also known as the middle esophageal diverticulum, and is an expansile diverticulum; ③ supradiaphragmatic diverticulum; it occurs in the upper part of the diaphragm in the lower part of the esophagus, and is also an expansile diverticulum. Pharyngoesophageal diverticula are more frequent, followed by supradiaphragmatic diverticula, and parabronchial diverticula are the least common. Whether or not an esophageal diverticulum produces symptoms last night depends on the size of the diverticulum, the location of the opening, and whether or not food and secretions are retained, and most symptoms are mild and atypical.
The anatomic basis of pharyngoesophageal diverticula is a posterior central defect between the oblique fibers of the inferior pharyngeal constrictor muscle and the transverse fibers of the cricopharyngeal muscle that is more pronounced on the slightly left side, so diverticula tend to occur on the left side.
Pharyngoesophageal diverticula are often not caused by a single factor and are mostly due to dysmotility and loss of relaxation of the cricopharyngeal and esophageal muscles with few muscle fibers. Most of the literature reports that most supradiaphragmatic diverticula are associated with esophageal dysmotility, esophageal hiatal hernia, and esophageal reflux. Esophageal reflux often causes esophageal muscle spasm, which increases the pressure in the lumen of the esophagus and results in bulging diverticula.
Middle esophageal diverticulum.
Most of the diverticula are of the distended type. Middle esophageal diverticula are completely similar to diaphragmatic diverticula in terms of etiology and presentation, while distended diverticula are due to scar traction caused by inflammation or tuberculosis in the parabronchial lymph nodes, which have the whole layer of esophageal tissue, including mucosa, submucosa and muscle layer, with a wide neck and narrow bottom shaped like a tent. The traction diverticulum occurs mostly in the anterior and right wall of the esophagus at the tracheal bifurcation. Some authors believe that some of the middle esophageal diverticula not related to esophageal motility abnormalities are congenital cysts of intestinal origin or have large openings and are connected to the lumen of the pharyngoesophagus at right angles, so that food is not easily retained and can be asymptomatic or mildly symptomatic, with only occasional irritating symptoms of itching in the larynx when food sticks to the diverticular wall and disappears when the food residue is dislodged by coughing or drinking.
If the diverticulum gradually increases in size, the accumulation of food and secretions begins to increase, sometimes automatically refluxing into the mouth, occasionally causing aspiration. During this period, the patient can hear a ringing sound in the pharynx due to air and food entering and leaving the diverticulum.
Due to the accumulation of food, the diverticulum will continue to increase and gradually fall, which is not conducive to the discharge of the accumulation within the diverticulum, resulting in the opening of the diverticulum is facing the lower side of the pharynx, the food swallowed first into the diverticulum and reflux occurs, at this time there are swallowing difficulties, and is progressively aggravated, some patients also have bad breath, nausea, loss of appetite and other symptoms. Some patients have malnutrition and weight loss due to difficulty in eating.
If there is aspiration, there are also comorbidities such as pneumonia, pulmonary atelectasis or lung abscess. Hemorrhage and perforation are less common comorbidities.
Corresponding signs and symptoms.
Clinical manifestations of pseudoesophageal diverticulum.
Patients often complain of mild dysphagia, with intermittent episodes or slow progression of symptoms. Pseudodiverticulosis of the esophagus is most often seen in patients in the 50- to 60-year-old age group, with more men than women.
Disease diagnosis.
Diagnosis and diagnostic criteria of pharyngoesophageal diverticulum.
There are few positive clinical physical examination signs, and in some patients, after swallowing a few mouthfuls of air, repeated pressure on the anterior border of the sternocleidomastoid muscle at the level of the cricopharyngeal muscle can be heard as a ringing sound.
The main means of diagnosis is X-ray examination, and the fluid plane is occasionally seen on plain film, and the diverticulum at the back of the esophagus can be seen by taking barium, and if the diverticulum is huge and obviously compresses the esophagus, a barium shadow can be seen after the barium enters the diverticulum, and then a barium shadow flows from the opening of the diverticulum to the esophagus below. Repeated changes in position during imaging are beneficial to the filling and emptying of the diverticulum, facilitating the discovery of small diverticula and observing whether the mucosa within the diverticulum is smooth, except for early malignant changes.
Endoscopy has certain risks, so it is not a routine examination, but only when malignancy is suspected or combined with other malformations, such as esophageal webbing or esophageal stricture. Before endoscopy, the patient is asked to swallow a black silk thread as the guide wire of endoscope, which can increase the safety of examination.
Diagnosis of supradiaphragmatic diverticulum and diagnostic criteria.
The diagnosis of supradiaphragmatic diverticulum is often confirmed by chest x-ray. A diverticular cavity containing a plane of fluid can sometimes be seen on a plain chest radiograph, and a diverticulum can be seen a few centimeters above the diaphragm on a barium study, often protruding to the right, but also to the left or anteriorly. It is extremely rare to see diverticula in the subdiaphragmatic abdominal segment of the esophagus. Diverticula can be combined with hiatal hernia, so multiple views are needed during imaging to avoid missed or misdiagnosis.
Endoscopy is risky and should only be performed when malignancy is suspected and when there is a combined malformation.
The middle esophageal diverticulum also relies on X-ray to confirm the diagnosis, when taking barium imaging, we should use the prone position or head low foot high position, and turn the body position left and right, in order to clearly show the outline of the diverticulum, because the opening of the middle esophageal diverticulum are relatively large, the contrast agent is easy to flow out from the diverticulum, not easy to stay inside.
Endoscopy is not very helpful for small and shallow esophageal diverticula and is only performed when diverticula malignancy is suspected.
Diagnosis of pseudo esophageal diverticula and diagnostic criteria.
Pseudodiverticula cannot be found on X-ray examination, and barium serving contrast can reveal multiple long-necked flask-like or small button-like pouches in the lumen of the esophagus, ranging in size from 1 to 5 mm, with scattered or restricted distribution, and there are more pseudodiverticula where the esophagus is obviously narrowed, so it is thought that esophageal strictures are related to inflammation around pseudodiverticula.
Endoscopic examination of the esophagus shows chronic inflammatory changes, and pseudodiverticulosis is only seen in a very small number of patients, and biopsy is not easy to confirm the diagnosis.
Many patients with pseudodiverticulosis often have Candida infection, which may be secondary, especially in diabetic patients.
Treatment measures.
Treatment of pharyngoesophageal diverticula.
The condition is mostly progressive and non-surgical conservative therapies are ineffective, so elective surgery should be performed as soon as possible after the diagnosis is clear and before the appearance of comorbidities.
Pre-operative preparation Generally, no special pre-operative preparation is needed, very few patients need intravenous rehydration to correct malnutrition, comorbidities should be actively treated, and surgery can be performed after the condition is controlled, so there is no need to wait for a long time.
If the nasogastric tube can be sent into the diverticulum under fluoroscopy before surgery, and repeatedly rinse and aspirate the residue, it is helpful to prevent misaspiration during induction of anesthesia.