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Enteroclysis: What Is It & Why Do We Do It?
This ASRT approved Category A Continuing Education article discusses the Enteroclysis exam in detail to aid the Technologists understanding of this procedure.
Author: Rachel Fierro R.T. (R) & Jenny Werner R.T. (R), written on Friday June 30th 2006 - 8:32 PM Credits: 1.5
The A.R.R.T. Continuing Education Requirements for Renewal of Registration states that Internet activities reported in a biennium may not be repeated for credit in the same or subsequent biennium. If you have already completed this article, DO NOT take this CEU article again.
Upon Completion, the reader will be able to:
Understand the anatomy involved in the procedure.
Discuss the indications that may be present prior to the exam.
List the advantages and disadvantages of the procedure.
Understand the importance of the appropriate prep prior to the procedure.
Discuss the insertion of the enteroclysis catheter.
List the common difficulties involved in placing the enteroclysis catheter.
The process of the infusion of barium.
List the reasons that methylcellulose is used.
Discuss the parameters that the Radiologist uses to determine a normal appearing small bowel.
List the common malabsorption diseases that may be found.
Discuss the relationship between Crohn’s disease and the enteroclysis small bowel study.
C. Ileum and Jejunum
III. Why we do it
B. Patient History
B. Catheter Placement
C. Injection of Barium
D. Injection of Methylcellulose
C. Inflammatory Diseases
VI. Conclusion and Summary
Enteroclysis, What is it and why do we do it?
The small intestine, also known as the small bowel, is an intricate part of our digestive system. It is here that carbohydrates, proteins, and fats that we eat are broken down. They are broken down into sugars, amino acids, and glycerin. These nutrient compounds are absorbed by the lining of the small intestine, released into the blood, and utilized by tissues through out the body. With the importance of this structure to the human body, it is imperative that the small bowel receive adequate diagnosis and treatment for the many diseases and disorders that can occur. The length and location of the small intestine can make this somewhat difficult. When a patient presents with abdominal pain with or without diarrhea, most clinicians will order an upper GI with small bowel follow through. The esophagus, stomach, and duodenum are easily evaluated in detail. The small bowel is then radiographed at periodic intervals and fluoroscopically spotted by the attending Radiologist. This type of SBFT can take hours to complete and detail of the lumen cannot be assessed as the loops of small intestine overlap as the barium progresses. A better diagnostic tool would be an enteroclysis small bowel exam. "Entero" is Greek for intestine. "Clysis" is Greek for washing out. Thus, enteroclysis is washing out of the intestine.
With this in mind, an Enteroclysis study of the small bowel is a minimally invasive radiographic procedure of the small intestine, which requires the introduction of a catheter into the small intestine followed by the injection of barium and methylcellulose. The barium coats the intestine and the methylcellulose distends the lumen to give a double contrast exam that allows for fluoroscopic visualization of the entire small bowel. There are several different types of enteroclysis catheters available, and the choice is usually determined by Radiologists preference, but cost can also play a factor in that decision.
It is going to be helpful to have a quick review of the stomach anatomy since the enteroclysis tube must be passed through the stomach before it can be properly placed into the jejunum of the small intestines.
The small bowel is approximately 22 feet long. It has three segments the duodenum, jejunum, and ileum. The jejunum and ileum will be evaluated during an enteroclysis procedure. The duodenum begins at the pylorus and curves around to end in the left upper part of the abdomen. The duodenum is important to the digestion of food because the ampula of Vater, which is located in this section, drains the bile and pancreatic juices into the intestinal tract. The duodenum is the shortest and widest part of the small bowel; it is approximately 10 inches long. The head of the pancreas is nestled in this C loop of the duodenum. The duodenal bulb, descending portion, horizontal portion, and the ascending portion make up the four segments of the duodenum.
The junction of the duodenum to the jejunum is the duodenojejunal flexure, which is held in place by the Ligament of Treitz. The Ligament of Treitz is a landmark for the Radiologist, it is routinely found in the left upper quadrant, just left of the midline. The Ligament of Treitz is not visualized under fluoroscopy, but the transition from the duodenum to the jejunum is very apparent.
The jejunum has a feathery appearance and the individual loops are close together. The small bowel is approximately two-fifths jejunum. The jejunum can be found in the left upper and left lower quadrants. The ileum has the smallest diameter of the three segments, and it has few indents, thus it is easily spotted on films. The small bowel is approximately three-fifths ileum. As the longest segment it transverses the left lower quadrant and both upper and lower right quadrants ending at the ileocecal valve in the right lower quadrant. The ileocecal valve joins the ileum to the cecum of the large bowel. Remember that the diameter of each segment continually grows smaller as you progress through the small bowel.
The enteroclysis study may be helpful in diagnosing almost all diseases that affect the small bowel. It may also be helpful in ruling out diseases in patients with unexplained abdominal complaints. There are several different indications for an enteroclysis study of the small bowel which include, but are not limited to:
Suspected or known small bowel obstruction
Inflammatory bowel disease
Unexplained gastrointestinal bleeding
Post surgical changes
The Radiologist may not be able to determine a diagnosis of a disease by radiographic findings only. Some diseases cause very subtle changes on radiographs, so it is beneficial to obtain a complete medical history from the patient prior to the exam. When obtaining the patients information it is recommended to obtain at least the following history:
Any abdominal pain, with location and length of symptoms
Diarrhea, or change in bowel movements
The presence of dark or tarry stools (indication bleeding)
Anemia (If possible get the most recent lab test results)
Any history of bowel obstructions
Weight loss or gain
Types and dates of abdominal surgeries
Types of previous test including endoscopes, lab tests, and other x-rays
There are two drawbacks to the enteroclysis small bowel follow through which need to be weighed carefully by the ordering physician and the radiologist. The disadvantages are:
The placement of the enteroclysis catheter is the largest disadvantage. It can be uncomfortable for the patient, even with the use of anesthetic spray and Xylocaine jelly or a similar lidocaine product.
The patient will receive higher doses of radiation in comparison to the traditional small bowel follow through exam during this exam.
There are several advantages to having an enteroclysis study of the small bowel in comparison to the traditional small bowel follow through study:
By placing contrast in the jejunum, the material does not have to be held up by normal pyloric activity.
This examination is much quicker than a routine single contrast Small Bowel Follow Through exam.
There is an increase in the distention of the lumen, which is very important; the distention straightens the circular folds and will help to determine its normalcy by having a measurable parameter. Fold thickness, ulceration, polyps, constrictions, and adhesive bands are more readily identified.
Distention of the lumen is controlled by the rate of infusion. Diseases may reduce this distention and can then be easily identified.
Distention of the small bowl makes it possible to display all dilated bowel loops simultaneously at the end of the exam.
Whenever possible a non-residue liquid diet should be done the day before the enteroclysis study. The patient should be NPO (nothing per oral) after midnight; this includes no smoking or chewing gum. This diet restriction reduces the normal fluid and cell outpouring into the small bowel lumen, which will improve the quality of the exam. Medications that reduce bowel motility should be given for 24 hours prior to the exam.
A laxative may be taken the day before the exam, magnesium citrate or a similar product is recommended. Although, it is not vital that the colon be clear of stool prior to the exam, it will help with the visualization of the small intestines. It is generally agreed that a clean ascending colon is necessary prior to an enteroclysis, because what is remaining in the ascending colon is often associated with what is present in the terminal ileum. If the ascending colon and the terminal ileum are not clear prior to the test, it is possible that it will retard the passage of barium. When the exam is being done to evaluate a partial small bowel obstruction, it is proper protocol to eliminate the laxative from the preparations.
The Insertion of the Enteroclysis Catheter
After the Radiologist has explained the procedure and reviewed the patient's medical history, the patient's throat may be sprayed with an anesthetic spray. The Radiologic Technologist should flush the enteroclysis catheter with water which lubricates the catheter and allows the guide wire to slide without resistance. Injecting air into the catheter’s balloon port prior to the insertion of the catheter is recommended. It is better to discover a malfunctioning balloon before it has been placed in the patient.
Sedation, even conscious sedation is usually not recommended because the patient needs to be able to communicate with the staff, move into different positions as requested, and must be able to get off the fluoroscopy table after the procedure in order to get to a restroom. The Technologist should determine if one nostril is easier for the patient to breathe through, and then administer Xylocaine lubricate to that nostril, 5-10 ccs is usually sufficient. The patient sniffs the Xylocaine lubricate into the nostril for maximum numbing. Place more Xylocaine lubricate on the enteroclysis catheter tip itself, this will ease the resistance in the patients nostril. The patient may sit up or lie down for the initial placement of the catheter. This is normally determined by the Radiologist's preference or patient's comfort. It is helpful to ask the patient to tuck their chin to their chest and to swallow frequently; this will aid the catheter in sliding down the back of the throat and into the esophagus, not the airway.
Once the catheter has passed through the back of the throat into the esophagus, the patients gagging reflex should subside. The Radiologist will advance the catheter until slight resistance is felt; this usually indicates the tip of the catheter is in the fundus of the stomach. Then as the catheter is held closely at the patients’ nose, the patient should lie back on the fluoroscopy table if they are not already in the supine position. Make sure the patient is comfortable and cover the patient with a blanket. Maximizing the patients comfort at this time is recommended because this allows the patient time to relax after a difficult start to the exam. Even with anesthetic spray and xylocaine jelly, some patients feel that the initial placement of catheter is uncomfortable. The Radiologist will then check the position of the catheter with fluoroscopy. Fluoroscopy may also be utilized during the entire placement of the catheter, if the Radiologist deems it necessary for guidance of the catheter into the correct position.
Common difficulties encountered during the initial placement of the enteroclysis catheter include the follow:
1. The catheter coils in the fundus of the stomach. When this occurs, rolling the patient onto their right side will allow gravity to point the catheter into the body of the stomach.
2. The catheter doubles back into the antrum of the stomach. The Radiologist will then pull the catheter back slowly, while holding the guide wire in place, this will cause the tip of the catheter to straighten slightly and point to the pylorus.
3. The catheter is being held up at the pylorus. When this occurs, rolling the patient to the left (LPO) will widen the bulb, allowing the catheter to advance into the duodenum.
4. The catheter stops at the inferior duodenal flexure. When this occurs it is helpful to apply pressure from a lead glove or compression paddle in order to advance the catheter toward the superior duodenal flexure.
5. The catheter has difficulties passing through the duodenojejunal junction. Rolling the patient laterally (left) and then into a slight posterior oblique position will allow the jejunum to fall forward and cause it to widen allowing the catheter to advance.
Finally, the patient should be placed supine and the position of the enteroclysis catheter should be checked under fluoroscopy. Once the catheter has been confirmed to be in proper position the balloon on the catheter should be inflated. Most enteroclysis catheters have a 15 to 20 ml balloon. When the balloon is inflated it should be visualized with fluoroscopy to be sure the balloon is placed beyond the ligament of Treitz. If the tube is not placed far enough into the small bowel, reflux into the stomach can occur. The patient would then feel uncomfortable, distended, and nauseated. If vomiting should occur the patient could aspirate or dislodge the position of the catheter. The Radiologic Technologist should then secure the catheter to the patient’s nose with tape and remove the guide wire. Take just a few minutes to reassure the patient that the catheter is correctly positioned and that it should not need to be manipulated any more. Encourage them to take a few deep breaths to help them relax. The placement of the enteroclysis catheter can be an unpleasant experience for the patient.
Infusion of Barium
Thin barium should be infused at a rate of 70 to 75 ccs per minute. The infusion rate should be fast enough to distend the small bowel. There are machines available to inject the contrast for the exam, but due to the cost of the machine, and the limited uses most facilities do not own the device. Thus, the infusing of contrast is usually done by hand. It is difficult to keep a constant level of contrast being infused. It is optimal to inject one 60 cc syringe of barium in 45 seconds. With the time it takes to disconnect the first syringe and reconnect the next syringe, you should be able to stay close to the 70 ccs per minute.
It is helpful to have a second set of hands to draw the contrast up in the syringes. It is important that the barium advance through the small bowel in an uninterrupted column and without causing focal distention of the lumen. It is vital to monitor the fluoroscopy image during the injection of contrast. If there appears to be inadequate distention of the small bowel, an increase of 10 ccs per minute may be added to the infusion rate. Likewise, if there is reflux of barium into the duodenum or stomach, then you will need to slow the infusion rate by 10 ccs per minute. If there is still reflux, it may be helpful to tip the head of the table up or the catheter may need to be readjusted
The Radiologist will be monitoring the leading edge of barium as it progresses through the small intestine. They will take occasional spot films of the progressing barium, especially if any abnormalities are noticed, and they will monitor the dilation of the lumen and check for reflux. The barium will be injected until the leading edge reaches the ileum. Depending on the patient’s size, the amount of barium injected can be from 180 ccs up to 500 ccs on average. More barium is required for large patients and for those with a dilated bowel and fluid retention (as in obstruction or malabsorption).
The Radiologist may request supine and prone abdominal films or bilateral oblique films at any time during the procedure. At this point in the procedure, the patient should be more relaxed, because the tube is stationary and there is usually little abdominal pain or patient discomfort associated with the injection of the barium. Being the methylcellulose does act as a laxative time is of importance, so work quickly while taking the overhead radiographs.
Methylcellulose is a form of polysacharide cellulose that has been treated to make it soluble in water. Cellulose is a long chain made of the sugar glucose. Methylcellulose is used in common products such as salad dressings, ice creams, and products such as laxatives. It is commonly used as a bulk laxative and as a suspending agent. It is nonirritating to the mucosal lining, unable to be absorbed, and has no toxic effects on the body. It has a natural tendency to retain water in the lumen, which promotes peristalsis and prevents lumen collapse. When used in an Enteroclysis study, this product mixes with the barium and produces the desired air contrast effect.
There are several reasons that methylcellulose is used in enteroclysis which includes the following:
It propels the barium into the distal ileum and the colon.
It distends the lumen, straightens the circular folds, and distends each segment. Non-distended loops can give a false impression of nodulation.
It has low diffusivity with compatible barium suspensions and thus, preserves an interface between the dense barium coating the mucosa and the water density of the distended lumen.
Intestinal surface detail can be studied even when two or three bowel loops overlap, as one can see through the barium to see each loop.
On entry into the colon, methylcellulose promotes evacuation of the barium.
Infusion of the Methylcellulose
Methylcellulose should be infused at a rate of 70 to 120 ccs per minute; with 1,500 to 2,000 ccs used on average for a good double contrast study. The rate of infusion should be a continuous injection of 60 ccs per 30 seconds. The infusion rate is related to the rate at which the barium moved through the patient. The faster the barium flowed, the faster the infusion of methylcellulose must be. Remember to watch the fluoroscopy image for reflux into the stomach. The reflux and possible aspiration is a concern, especially in the elderly or other compromised patients. This rate of infusion of the methylcellulose is continued until there is sufficient distention of the distal and terminal ileum. If the progress is too fast and distention is inadequate, the rate of infusion should be increased. This will cause proximal jejunal distention, which will cause a slowing of the more distal bowel loops.
During the injection of methylcellulose, the Radiologist will obtain spot films as each segment is distended. Compression of individual loops with either a compression spoon or paddle and rotation of the patient may be necessary as the procedure progresses. The Radiologist will release the compression gradually in order to avoid mixing the barium and methylcellulose. If the two contrast mix, it would dilute the double contrast effect that is desired.
The Radiologist routinely examines the jejunum and upper ileum while the patient is in the right posterior oblique position. The distal ileum will be demonstrated with the patient in a left posterior oblique position. The terminal ileum is the most difficult problem for the Radiologist to visualize. The accumulation of barium in the cecum can over lap and obstruct the Radiologists view of the terminal ileum. You will notice the Radiologist paying very close attention to this area, and they will take spot films of it during the first bolus of barium into the cecum.
A supine and prone, or bilateral oblique abdominal film may be taken when the methylcellulose has reached the terminal ileum. If the distal bowel loops are not visualized, a 35-degree caudal angle may be helpful on posterior oblique or an AP radiographs. Upon completion of evaluating the terminal ileum, the Radiologist will than have the balloon deflated and may request that barium or methylcellulose be injected as the tube is pulled back slowly into the duodenum. This allows the Radiologist to evaluate the duodenal loop. A spot film may be taken of the duodenum to document that the entire small bowel was evaluated.
Once the duodenum has been evaluated by the Radiologist, the tube will be completely removed. The removal of the tube is generally not traumatic for the patient. Offer the patient some tissues, and assist them to the restroom. The fast acting methylcellulose will cause the patient to evacuate shortly after the exam is completed.
Normal Appearing Small Bowel
The enteroclysis exam allows the Radiologist to study several parameters within the small bowel. This includes:
Fold shape: The folds are less pronounced or possible absent in the ileum. The folds run fairly straight and parallel, joining the bowel wall in the form of rounded corners. At times in the ileum, the folds may crowd together on the concave side of a bowel loop, creating a triangular fold pattern.
Fold thickness: The folds are normally 1.8 mm thick in the jejunum, and 1.5 mm thick in the ileum. When the thickness exceeds 2.5 mm in the jejunum or 2.0 in the ileum, it is considered a pathologic finding.
Number of folds: 4 to 7 folds per inch are normal for the proximal jejunum and 2 to 5 folds per inch is normal for the distal ileum.
Fold Height. The height of the folds is 3 to 7 mm in the jejunum and 1.5 to 3.5 mm in the ileum. It is worth mentioning that the height of the folds may vary considerably within the same segment of the bowel, thus the Radiologist visualizes the entire segment for the height of the folds.
Lumen Diameter: There is a gradual decrease in lumen diameter from the jejunum into the ileum. The upper jejunum averages from 3.0 cm to 4.0 cm, 2.5 cm to 3.5 in the lower jejunum, and 2.0 cm to 2.8 cm in the ileum. Abnormal diameters are anything that exceeds 4.5 cm in the upper jejunum, 4.0 cm in the distal jejunum, and 3.0 in the ileum.
Wall Thickness: When two adjacent loops are found to be parallel over a distance of at least 4 cm, with abdominal compression, the distance between the two represents the combined wall thickness. Half of this measurement is the thickness of a single loop. The wall thickness is the same throughout the small bowel. A wall thickness greater than 2 mm is considered abnormal.
Small Bowel diseases
Diseases of the small bowel can be grouped into three main categories; neoplasms, malabsorption, and inflammatory. Neoplasms are polyps of the intestine that form carcinoid tumors. Malabsorption is the failure to transport nutrients from the intestines into the body. Malabsorption may be limited to selected materials, thus it is pertinent that the radiologist be able to correlate radiographic findings and patient symptoms in order to diagnose the possibility of malabsorption diseases. Radiologists group malabsorption into two separate groups: those with enteroclysis changes that are subtle, and those with specific patterns. Diseases in which enteroclysis changes are subtle, non-specific changes have differential diagnosis that is influenced by clinical history and small radiographic patterns which include Whipple’s Disease, lymphangiectasis, amyloidosis, abetalipoproteinemia, mastocytosis, and macroglobeulinemia. Those diseases in which an almost specific enteroclysis pattern occurs includes the bacterial overgrowth syndromes, adult Celiac Disease (CD), adult Cystic Fibrosis (CF), Zollinger-Ellison Syndrome (ZES), and short bowel syndrome. We will concentrate on the diseases with specific enteroclysis patterns.
Polyps are abnormal outgrowths of tissue that protrude into the lumen of the intestine. Cells in the tissue sometimes grow on the surface of the tissue causing a polyp, which always arise from the inner lining of the intestinal wall. Polyps are a common form of neoplasm. Most polyps are never noticed because they cause no problems. Polyps of the small bowel do not seem to have malignant potential, but the can produce obstructions. If the polyp grows too large in can impede the normal peristalsis of the intestines, or small polyps can pull part of the adjoining sections together resulting in intussusception.
Carcinoid tumors are cancers that are found in the digestive tact. The majority of carcinoid tumors is slow growing and can be treated and often cured. Metastasis from carcinoid tumors is relative to the size of the lesion. Lesions 1 cm or less metastasizes in 2% of case, tumors 1-2 cm metastasize in 50% of cases, and lesions greater than 2 cm metastasize 85% of cases. Since most carcinoid tumors of the small intestine do not present any symptoms, early diagnosis is essential. A few symptoms a patient may experience include pain, weight loss, palpable mass, intestinal obstruction, or a perforation of the intestinal tract.
Carcinoid tumors account for one-third of gastrointestinal carcinoid, and it is the most common tumor of the small intestine. The ileum accounts for 91% of all carcinoid tumors. Incidence of tumors increase the closer to the cecum the bowel gets. 15-35% of carcinoid tumors have multiple tumors. During an enteroclysis well-defined smooth rounded, intra-lumen filling defects can be seen. The presence of multiple polyps of similar appearance strengthens the suspicion of carcinoid tumors, but it is possible to make a diagnosis from only one noted defect. As the disease progresses further tumor growth may cause crowding of the folds surrounding the tumor, kinking the bowel wall causing narrowing of the lumen. At this stage CT becomes mandatory.
Bacterial overgrowth syndrome is a result of a bacterial overload in the small bowel. The normal small bowel contains up to 104 organisms per milliliter in the proximal jejunum virtually all are aerobic. More organisms are found in the distal ileum, this is because of the incomplete continence of the ileocecal valve. Restriction of bacterial growth in the normal small bowel relies on gastric acid, peristalsis, and on immune defenses. Any malfunction of these defenses leads to an increased number of organisms and anaerobic bacteria will be present. A bacterial overload of any cause adversely affects digestion and absorption. Diseases that are associated with bacterial overgrowth syndrome are jejunal diverticulosis, and pseudo-obstruction. Bacterial overgrowth results from retention within the jejunal diverticula’s. Enteroclysis studies will outline the diverticula’s. Pseudo-obstruction is a condition with clinical manifestations of a small bowel obstruction without the mechanical obstruction. Barium passes extremely slowly without much peristalsis. Numerous underlying diseases may cause pseudo-obstructions such as lupus, scleroderma, or Parkinson's disease.
Celiac disease (CD) is an immune disorder that results in damage to the small bowel lining. This is caused by eating foods with gluten; gluten is a form of protein found in some grains. This damage makes it hard for the body to absorb nutrients. The enteroclysis is important in aiding with the diagnosis of adult CD. The enteroclysis will show a wider than normal separation of mucosal folds in the distended proximal jejunum. Three or fewer folds over one inch is a diagnostic of celiac disease. An increased number of slightly thickened folds in the ileum are another diagnostic feature. Fold thickening may occur and is due to edema. Strictures are a complication of CD, and it resembles lymphoma. There is a relationship of CD to gastrointestinal malignancy.
Cystic Fibrosis (CF) is a genetic disorder that affects the respiratory, digestive, and reproductive systems. The condition affects the cells that produce mucus, sweat, saliva, and digestive juices. Instead of these secretions being thin and slippery, the secretions become thick and sticky. Most people are diagnosed by age three. Less than 2% of patients with CF are diagnosed after the age of 18. Enteroclysis is an excellent study for this percentage. A diagnosis of CF can be suggested in adult patients when the duodenum has fold thickening, nodular filling defects, flattening of the folds, and lumen dilation. This mainly occurs in the descending portion of the duodenum. Distal loops of the small bowel are found to have an irregular network of curving lines, presumably surrounding packets of mucus.
Zollinger-Ellison Syndrome (ZES) is a rare disorder that causes tumors in the pancreas and duodenum and ulcers in the stomach and duodenum. ZES comprises gastric acid hyper secretion; sever peptic ulcer disease, and gastric-secreting tumors. These tumors have a high frequency of cancer, thus early detection is necessary. Patients have outpouring of several liters of acidic fluid a day, which frequently causes peptic ulcers in the duodenum or jejunum. The enteroclysis may show fold thickening, erosions, and poor adherence of barium to the intestinal walls in the duodenum. Moderate fold thickening and fluid increase may be noted in the proximal jejunum.
Short bowel syndrome refers to the malabsorption of nutrients due to disease or surgical removal of part of the small intestines. Removal of about 50% of the small bowel can cause malabsorption. For oral nutrition, the minimal amount of small bowel needed with the loss of colon has been reported to be 150 centimeters, but with the colon intake 50 to 70 centimeters is adequate. The enteroclysis small bowel study is helpful in determining the length of the residual bowel along with demonstrating any future involvement of the original bowel disease.
Inflammatory Bowel Disease
Inflammatory bowel disease can involve either or both the small and large intestine. Crohn’s disease and ulcerative colitis are the most common inflammatory bowel diseases. Ulcerative colitis involves the colon, and Crohn’s disease can involve any part of the GI tract, but most frequently in involves the distal small bowel and colon. The inflammation can produce small ulcers or deep fissures that can lead to fistulas, obstructions, perforation, blood loss, or malignant neoplasms. Crohn’s disease can be the most devastating disease that involves the small bowel.
Crohn’s disease is also referred as regional enteritis. It is an autoimmune disease that attacks the cells in the gastrointestinal system. The inflammation from Crohn’s disease frequently occurs at the ileum, but it may affect any area of the digestive track. The disease causes severe damage to the intestinal tract. The lumen may appear irregular with ulcerations. Fold thickness may increase. The lumen may narrow creating a string like appear. The disease may create fistulas. As the disease progresses surgical removal of segments of the small bowel may be needed. The disease has a huge impact on the lives of patients. The patient will need frequent follow-up exams to properly diagnosis the disease and then to help manage the disease properly.
The enteroclysis should be the method of choice for the following indications:
To demonstrate the early changes of the disease.
To depict the full extent of involvement and the possible presence of lesions.
To determine the cause of any clinical changes in a Crohn’s patient.
To distinguish among spasm, active stenotic disease, and a fibrous stricture.
To investigate postoperative complication of Crohn’s disease.
To rule out positively the presence of small bowel Crohn’s disease.
An enteroclysis small bowel study is an invasive procedure that distends the lumen and allows for fluoroscopic evaluation of the entire small bowel. This double contrast study is excellent in aiding the Radiologist and the attending physician in evaluating and diagnosing malabsorption and inflammatory diseases of the small bowel. The placement of the catheter is difficult and can be quite lengthy, but the advantages outweigh the disadvantages when determining the presence of small bowel obstructions, neoplasms, inflammatory bowel diseases, gastrointestinal bleeding, or malabsorption diseases.
The combination of barium and methylcellulose is a double contrast exam.
The small bowl has three segments: duodenum, jejunum, and ileum.
The duodenum is the shortest and widest part of the small bowel.
The duodenal bulb, descending portion, horizontal portion, and the ascending portion make up the four segments of the duodenum.
The junction of the duodenum to the jejunum is the duodenojejunal flexure, which is held in place by the Ligament of Treitz.
The jejunum is feathery in appearance and the individual loops are close together.
The jejunum is located in the left upper and lower quadrants of the abdomen.
The ileum is the longest segment of the small bowel, and is located in the left lower quadrant and both the upper and lower right quadrants.
The ileocecal valve joins the ileum to the cecum of the large bowel.
Indications for an enteroclysis include: obstruction, neoplasms, inflammatory bowel disease, gastrointestinal bleeding, and malabsorption.
While obtaining the patient history document: abdominal pain, bowel habit changes, presence of dark or tarry stools, anemia, history of bowel obstructions, weight changes, abdominal surgeries, and any previous tests completed.
Disadvantages of an enteroclysis small bowel study are that the placement of the tube is uncomfortable and there is a higher radiation dose involved in the procedure.
The reduction of normal fluid and cell outpouring into the small bowel lumen as a result of diet restrictions improves the quality of the procedures.
When a partial small bowel obstruction is indicated, it is proper protocol to eliminate the laxative from the test prep.
The common difficulties in placing the enteroclysis tube includes: coiling in the fundus, doubling back into the antrum, being held up by the pylorus, stopping at the inferior duodenal flexure, and difficulties passing through the duodenojejunal junction.
Barium should be infused at a rate of 70 to 75 ccs per minute.
It is important that the barium advance in an uninterrupted column and without causing focal distention of the lumen.
Increase the rate of barium by 10 ccs per minute if there is inadequate distention of the lumen, or decrease the rate by 10 ccs per minute if there is reflux of barium into the duodenum or stomach.
Depending on the patients size, the amount of barium injected can be 180 to 500 ccs.
Methylcellulose is used because it: propels the barium, distends he lumen straightening the circular folds and distending each segment, preserves an interface between the dense barium coating the mucosa and the water density of the distended lumen, allows studying of the intestinal surface details, and promotes evacuation of the barium.
Methylcellulose should be infused at a rate of 70 to 120 ccs per minute.
Reflux and possible aspiration of the methylcellulose is a concern.
If the progression of the methylcellulose is too fast and distention is inadequate, the rate of infusion should be increased.
The Radiologist releases compression gradually in order to avoid mixing the barium and methylcellulose in order to maintain the double contrast affect.
The jejunum and upper ileum is examined while the patient is in the RPO position and the distal ileum when the patient is in the LPO position.
The Radiologist will study fold shape, fold thickness, the number of folds, fold height, lumen diameter, and wall thickness.
The lumen folds are less pronounced or possible absent in the ileum.
The folds are normally 1.8 mms thick in the jejunum and 1.5 thick in the ileum.
There are 4 to 7 folds per inch in the proximal jejunum and 2 to 5 folds per inch in the distal ileum.
The height of the folds is 3 to 7 mms in the jejunum and 1.5 to 3.5 mms in the ileum.
There is a gradual decrease in lumen diameter from the jejunum into the ileum.
The wall thickness is less than 2 mm’s, and the wall thickness is the same throughout the small bowel.
Polyps are abnormal outgrowths of tissue that protrudes into the lumen of the intestine.
Polyps are a common form of neoplasm.
Carcinoid tumors account for one-third of gastrointestinal cancer, and it is the most common tumor of the small intestine.
During an enteroclysis well-defined smooth rounded, intra-lumen filling defects can be seen. The presence of multiple polyps of similar appearance strengthens the suspicion of carcinoid.
As carcinoid tumors progresses, further tumor growth may cause crowding of the folds surrounding the tumor, kinking the bowel wall causing narrowing of the lumen.
Malabsorption is the failure to transport nutrients from the intestines into the body.
Malabsorption Diseases in which a specific enteroclysis pattern occurs include bacterial overgrowth syndromes, adult Celiac Disease, adult Cystic Fibrosis, Zollinger-Ellison Syndrome, and short bowel syndrome.
Bacterial overgrowth syndrome results from bacterial overload in the small bowel adversely affecting digestion and absorption. Jejunal diverticulosis and pseudo-obstructions are associated with bacterial overgrowth syndrome.
Celiac Disease is an immune disorder that damages the small bowel lining making it hard for the body to absorb nutrients. CD results in a wider separation of mucosal folds in the distended proximal jejunum.
Cystic Fibrosis is a genetic disorder that affects the respiratory, digestive and reproductive systems causing secretions to become thick and sticky. These thickened secretions will usually cause defects in the duodenum.
Zollinger-Ellison Syndrome is a rare disorder that causes tumors in the pancreas and duodenum, and ulcers in the stomach and duodenum.
Short bowel syndrome refers to the malabsorption of food nutrients due to disease or surgical removal of part of the small bowel.
Crohn’s disease is the most common inflammatory bowel disease in the small bowel.
Inflammatory bowel disease most frequently involves the distal small bowel and proximal colon.
The inflammation caused by Crohn’s creates small ulcers or deep fissures that can lead to fistulas, obstructions, perforation, blood loss, or malignant neoplasms.
Crohn’s is an autoimmune disease that attacks the cells in the gastrointestinal system.
Crohn’s disease may cause the lumen to appear irregular with ulcerations, fold thickness to increase, the lumen to narrow creating a string like appearance, and fistulas may form.
An enteroclysis is superb at evaluating malabsorption and inflammatory diseases of the small bowel.
American College of Radiology. “ACR Practice Guideline for the Performance of an Enteroclysis Examination in Adult.” 8 Nov. 2004
Gore, Richard M.D., Marc Levine M.D., and Igor Laufer M.D. “Textbook of Gastrointestinal Radiology Volume One”. Section VII Small Bowel 1994 pages 766-786. Philadelphia: W.B. Saunders Company.
Indiana University School of Medicine. “Enteroclysis Resident e-Handbook.” 30 Oct.2004 https://www.indyrad.iupui.edu/public/ResHandbook/Fluoro/Entero.html
Laufer, Igor M.D., and Marc Levine M.D. “Double Contrast Gastrointestinal Radiology 2nd Edition”. Small Bowel 1992 pages 363-422. Philadelphia: W.B. Saunders Company.
Science Toys, "Ingredients--What's in the stuff we buy?" 15 June, 2005, http://sci-toys.com/ingredients/methylcellulose.html
Tashijian, Jospeh M.D., Personal interview, 25, Feb. 2005.
We would like to thank Dr. Joseph Tashijian for his interview and his encouragement. Dr. Tashijian is more than a caring, knowledgeable Radiologist, we also consider him a wonderful friend. Thanks Dr. T.