X-ray of the stomach and duodenum: indications and preparation

Upper gastrointestinal tract radiography with contrast provides real-time visualization of the esophagus, stomach, and duodenum. The patient drinks a barium suspension, sometimes with gas-forming granules for double-contrast imaging. The physician observes the passage of the contrast, takes targeted images, and evaluates the shape, folds, peristalsis, and the presence of obstructions. This method does not replace endoscopy, but it is effective in identifying motility disorders and mechanical obstructions, and provides functional information not available on static images. [1]

In modern clinical practice, the focus of examination has become more focused. For mucosal diseases and bleeding control, endoscopy is the standard, as it allows for biopsy and treatment; fluoroscopy is not the method of choice in these scenarios. However, fluoroscopy remains in demand for assessing patency, gastric emptying, postoperative leaks, and a number of congenital anomalies in children. [2]

The technology is based on pulsed fluoroscopy, which reduces radiation exposure, and digital loop recording. Due to its dynamic nature, the method allows for detection of reflux, duodenogastric reflux, pathological retroperistalsis, and the "obstruction level," which is not possible with a standard plain film. This complements endoscopy and computed tomography for structural and functional imaging. [3]

It's important to understand the limitations. This test doesn't allow for biopsy, is less effective at detecting small superficial defects, and doesn't replace endoscopy when an ulcer or tumor is suspected. In cases of acute upper gastrointestinal bleeding, fluoroscopy has virtually no place. The choice of method is based on the clinical question. [4]

Table 1. Where is the first choice method, and where is it an auxiliary one?

Clinical task	The role of fluoroscopy of the stomach and duodenum
Suspected mechanical obstruction of the gastric outlet, anastomotic stenosis	Often the first step method for localizing the level of obstruction and assessing contrast passage
Post-operative monitoring of the stomach and esophagus, leak detection	Method of choice with water-soluble contrast in the first day
Suspected congenital malrotation in an infant	The "gold standard" for confirming the diagnosis in the presence of bilious vomiting
Peptic ulcer, bleeding, mucosal tumors	Ancillary role, the method of choice is endoscopy with the possibility of treatment and biopsy
Summary of current recommendations and reviews. [5]

When prescribed: indications by groups

Primary stratification of dyspepsia and upper abdominal pain is based on clinical findings and endoscopy if any alarming signs are present. Fluoroscopy is appropriate when functional assessment of bowel movements, confirmation of suspected stenosis, clarification of the obstruction level, or when endoscopy is unavailable is required. A number of regional guidelines emphasize that this method is feasible if there is an experienced center and specific patency issues are addressed. [6]

If duodenal obstruction or pyloric syndrome is suspected, the study helps visualize contrast retention, gastric dilation, retroperistalsis, and "filamentous" contrast exit. This expedites decision-making regarding tactics and the selection of the next imaging step. [7]

In the postoperative period, fluoroscopy is prescribed for the early detection of suture or anastomotic leaks, strictly beginning with water-soluble contrast, which is safer in the event of a leak. If no leak is detected, if suspicion persists, a switch to dilute barium may be made to improve sensitivity. This two-stage approach is enshrined in professional documents. [8]

In children with bilious vomiting, the upper gastrointestinal series remains the reference method for confirming malrotation and midgut volvulus. Sensitivity, according to reviews, is high, and correct assessment of the position of the ligament of Treitz is essential for emergency surgical management. [9]

Table 2. Indications and preferred alternatives

Situation	X-ray examination of the stomach and duodenum	Alternatives
Dyspepsia without alarming signs	Considered on a case-by-case basis, usually not required	Endoscopy as indicated, non-invasive tests
Suspected outlet obstruction	Yes, to localize the obstacle	Computed tomography for cause and prevalence
Suspected leakage after surgery	Yes, water-soluble contrast first	Computed tomography in doubtful cases
Bilious vomiting in an infant	Yes, reference method	Ultrasound as a triage, computed tomography selectively
According to specialized guides and reviews. [10]

Contraindications and precautions

If perforation of a hollow organ is suspected, only water-soluble iodine-based contrast should be used. Barium, if introduced into the abdominal cavity, causes severe peritonitis. If no leak is detected with a water-soluble agent, but clinical suspicion remains high, careful use of dilute barium is acceptable to improve diagnostic accuracy. [11]

The risk of aspiration dictates the avoidance of hyperosmolar diatrizoate and the selection of low-osmolar iodine-containing agents in patients with swallowing difficulties or a high risk of contrast aspiration. These considerations are reflected in professional parameters and training protocols. [12]

In cases of severe intestinal obstruction, severe constipation, or suspected megacolon, a barium study may worsen colon retention. In these scenarios, the method is reconsidered or an alternative approach is chosen. In pregnant women, the study is performed only under strict indications, with dose optimization and fetal protection. [13]

Allergic reactions to barium itself are extremely rare, but intolerance to flavorings and constipation due to the barium fixation are possible. The patient is advised in advance to drink more fluids after the procedure and, if necessary, take a mild laxative. [14]

Table 3. Contraindications and what to do instead

Problem	What not to do	A safe alternative
Suspected perforation	Do not give barium	Water-soluble iodine-containing contrast at the start
High risk of aspiration	Do not use hyperosmolar solutions	Low osmolar iodine-containing agent under control
Severe obstruction, persistent constipation	Avoid barium	Review of indications, computed tomography as appropriate
Pregnancy	Avoid loose indications	Postpone or choose ultrasound, optimize the protocol if necessary
According to ACR parameters and RSNA patient materials. [15]

How the procedure works: preparation, contrast, stages

Preparation typically includes abstaining from food and drink after midnight, clarifying medication and allergy information, and warning about possible pregnancy. On the day of the examination, the patient wears comfortable, metal-free clothing or a hospital gown and removes jewelry and removable items. These guidelines improve image quality and reduce the number of repeat exposures. [16]

Contrast options include single-contrast barium and double-contrast with the addition of gas-forming granules, which smooth out mucosal folds. If there is a risk of leakage or after recent surgeries, a water-soluble iodine-containing contrast agent is always used first; if the test is negative and there is a persistent suspicion of microleakage, dilute barium is used. This provides a balance between safety and sensitivity. [17]

During the examination, the table and X-ray tube are repositioned, the doctor asks the patient to hold their breath, applies gentle pressure on the abdomen to ensure even barium coverage, and records a series of images and short video loops. For pediatric examinations, pediatric exposure modes are used, sometimes with a special platform for safe tilting of the body. For infants, the volume and rate of contrast are calculated individually. [18]

After the procedure, the patient returns to a normal diet, and stool may temporarily become lighter. To prevent constipation, it is recommended to drink more water and, if needed, take a mild laxative. If bowel movements are not possible or if pain intensifies, the patient should contact their physician. [19]

Table 4. Preparation for the study: patient checklist

Paragraph	Why is this necessary?
Do not eat or drink the night before the test.	An empty stomach improves image quality.
Report medications and allergies	Correcting the scheme and choosing contrast
To clarify the fact of pregnancy	Decision on the advisability and methods of protection
Remove metal and jewelry	Elimination of artifacts and repeated exposures
Based on RSNA materials for patients. [20]

Pediatrics: Malrotation and midgut volvulus

In neonates and infants with bilious vomiting, the upper gastrointestinal series remains the standard for confirming malrotation and volvulus. The key to diagnosis is the location of the ligament of Treitz and the course of the duodenum in the AP and lateral views. A properly performed and interpreted series provides high sensitivity, which is critical for deciding on urgent surgery. [21]

Despite the growing role of ultrasound in triage, contrast imaging more reliably reveals the anatomy and course of the intestine. Computed tomography (CT) is used selectively in children due to the dose burden, and if there is any doubt, urgent surgical intervention is recommended if there is clinical evidence of volvulus. This algorithm has been reflected in systematic reviews of recent years. [22]

The quality of the examination in children is significantly dependent on the lateral projection. Some studies emphasize that proper lateral imaging technique improves the accuracy of determining duodenal malposition. Quality criteria include positional stability, adequate filling, and visibility of landmarks. [23]

The decision regarding additional imaging and surgical tactics is made multidisciplinary. The shorter the interval between recognition of clinical signs and confirmation of malrotation, the lower the risk of intestinal ischemia and necrosis. This explains the established place of this method in pediatric emergency practice. [24]

Table 5. Algorithm for bilious vomiting in an infant

Step	What to do	Target
Triage	Assessment of vital functions	Rule out shock and severe dehydration
Primary visualization	Ultrasound if possible	Quick search for alternatives and indirect signs
Confirmation	Upper gastrointestinal series	Confirm malrotation and obstruction level
Tactics	Urgent consultation with a surgeon	The decision to perform the Ladd operation
Synthesis of modern reviews. [25]

Contrast: What and When to Use It

Barium suspension remains the standard for assessing mucosal relief and kinetics without the risk of leakage. To improve contrast, gas-forming granules are used, creating an air component that sharpens mucosal folds. This improves the detection of subtle changes. [26]

Water-soluble iodinated contrast agents are mandatory for postoperative monitoring and suspected perforation. In cases of aspiration risk, low-osmolar solutions are preferred to reduce the risk of chemical pneumonitis. These principles are detailed in professional guidelines. [27]

If a water-soluble leak test is negative but doubt remains, switching to dilute barium is acceptable to increase sensitivity. This "two-step" approach is widely accepted in practical guidelines. [28]

The choice of contrast volume and viscosity is individual and depends on the task. When assessing evacuation, standard dosage and fixed imaging intervals are important, and if stenosis is suspected, serial fluoroscopy is used until contrast appears in the jejunum. [29]

Table 6. Selection of contrast for clinical question

Clinical situation	First choice	When to change your approach
Routine assessment of form and motor skills	Barium, double contrast if possible	If signs of leakage occur, switch to an iodine-containing agent.
Early postoperative period	Water-soluble iodine-containing contrast	If the test is negative and there is high suspicion, add diluted barium.
Risk of aspiration	Low osmolar iodine-containing agent	Avoid hyperosmolar solutions
Suspected perforation	Water-soluble contrast only	Barium is acceptable as a second step in case of a negative test and high suspicion
According to ACR parameters and training materials. [30]

Radiation Safety: Guidelines for Informed Consent

The typical effective dose for an upper cystoscopy with barium is approximately 6 millisieverts, which is comparable to approximately 2 years of natural background radiation. The actual dose depends on the duration of the fluoroscopy, body weight, and technique, and modern systems use pulsed mode and automatic modulation, reducing exposure. For comparison, intravenous urography delivers approximately 3 millisieverts. [31]

Dose reduction is achieved by clearly defining the clinical question, choosing short cine loops instead of continuous fluoroscopy, using limiting diaphragms, and digital recording. Pediatric protocols call for reduced currents and voltages based on the child's size. These approaches are regularly updated by professional societies. [32]

In emergency situations where a leak or leak is suspected, the prevention of complications outweighs the small risk of radiation exposure, but the team is required to apply the "as low as reasonably achievable" principle and record key frames rather than long continuous fluoroscopy.[33]

It is helpful for patients to compare doses with natural background radiation and understand that no X-ray radiation remains in the body after the procedure. This reduces anxiety and increases compliance with necessary tests. [34]

Table 7. Estimated doses for patient discussion

Study	Estimated effective dose	Comparable to the background
Upper section with barium	~6 mSv	~2 years
Intravenous urography	~3 mSv	~1 year
Computed tomography of the abdomen and pelvis, one phase	~7.7 mSv	~2.6 years
According to the RSNA summary table for patients. [35]

How is a radiologist's report formulated?

The protocol describes the shape and position of the stomach, the nature of its folds, the presence of diverticula, the level of obstruction, the rate of evacuation, signs of reflux and retroperistalsis, and the contours of the duodenal bulb and descending portion. With double-contrast imaging, minor filling defects and niches are clarified. These parameters standardize the quality of the description and improve the comparability of studies. [36]

Following surgery, clear statements regarding the presence or absence of a leak, its level and estimated volume, as well as the patency of the anastomosis and contrast retention are mandatory. If a water-soluble test is negative and a microleak is still suspected, the advisability of a barium study or computed tomography is indicated. [37]

In children with suspected malrotation, the position of the ligament of Treitz relative to the spine and gastrocolic ligament, the direction of the duodenal loop, and the nature of contrast passage are emphasized. Correct fixation of these landmarks directly influences emergency management. [38]

When associated findings, such as large hiatal hernias, are identified, practical recommendations are made for next steps, including endoscopy for morphological verification if necessary. This ensures continuity between imaging and patient management. [39]