Double-contrast examination of the stomach

A double-contrast study is performed whenever morphology of the stomach has to be

evaluated. We primarily look for fine lesions of the gastric mucosa. For example, presence of a gastric polyp signals a precancerous condition. Mucosal folds of the stomach (columnae rugarum), surface pattern of the mucosal glands (area gastricea) have to be visualized as well.

Barium coating helps to better examine gastric wall contours and recognize excess

collections. Luminal distribution of barium can be controlled by turning the patient to his side.

Fig.11.: Anatomical sections of the stomach Fig.12.: Double-contrast gastrography 13.4.4. Diseases of the stomach

In general, diseases of the stomach, irrespective of the etiology, most frequently affect the gastric antrum, or they are originating from the antrum. As it is also often said in the stomach the antrum is the ―locus minoris resistentiae‖.

161 Gastric ulcer

Clinical presentation: Epigastric pain that typically occurs after meals.

Characteristically, ulcers cause tissue defects in the stomach wall, therefore on radiography they present as excess contrast collections in profile views. When pictured ―en face‖ an adhesive spot is seen, as the contrast media fills out the tissue defect. Ulcers can reach a large size when they are called giant ulcers. In postoperative states, in burns and in trauma patients the gastric mucosal defects evolve rapidly forming stress ulcers.

Typically, gastric ulcers follow a relapsing remitting disease pattern and could spontaneously heal by time. However, as soon as a recurrent inflammation is seen at the same site the diagnosis is changed for chronic ulceration. The clinical symptoms worsen as the recurring cycles of inflammation and fibrosis lead to scar tissue formation. Scarring can be constrictive.

It is visible on the radiographs that due to the fibrosis the gastric folds are radially arranged around the ulcer rim leading to a characteristic stellate appearance.

Fig.13.: Gastric ulcer

Ulcers located on the greater curvature show greater tendency of malignant transformation;

sometimes they begin with an ulcerated carcinoma. In contrast to benign lesions malignant ulcers typically do not form round contrast collections, and due to infiltration of the stomach wall no peristaltic activity can be detected around them, rather parietal rigidity is seen.

Benign gastric ulcers are seen as round collections on the GI series. At the neck of the ulcer a collar formed by the edematous mucosal ring is called the Hampton line, which appears as a thin, sharp translucent line on the radiograph. Opposite to the ulcer the gastric wall shows a permanent finger like invagination corresponding to a stationary peristaltic wave.

Fig.14.: Radiographic image:

typical gastric ulcer

Fig.15.: Ulcerated carcinoma occurs typically on the grater curvature with irregular filling defect and infiltration of the surrounding wall

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Gastric polyps

Clinical presentation: asymptomatic, can be an accidental finding.

Identification of gastric polyps is a highly important role of the upper GI series. Polyps in the 5 mm range are already well detectable. It is considered a precancerous condition and

generally presents as a round mass with a luminal protrusion. If pictured ―en face‖ in the sagittal plane they can be seen as round, sharp contoured lesions.

Fig.16.: Radiographic image: in the gastric body multiple, 5 mm long and smaller ring-like lesion can be identified.

Hiatus hernia

Clinical presentation: axial hernia is typically associated with complaints of gastroesophageal reflux; patients can also experience tightness around the chest. Larger hernias can lead to a gastric emptying disorder.

Axial and paracardial hiatus hernias can be distinguished. The clinical signs are important to differentiate between the two entities as they may require a different therapeutic approach. In axial type hernias the gastric cardia and part of the stomach is displaced into the thoracic cavity. This condition is always accompanied by gastresophageal reflux as the cardia loses its function and it does not prevent regurgitation. The patient complains of heartburn. In

paracardial hiatus hernias the cardia is located below the diaphragm, while the herniated segment of the stomach may compress the cardia. The patients usually remain symptom free, thus paracardial hernias are often diagnosed accidentally.

In the everyday practice we also often see sliding hernias. In these, the hernia could only be detected in certain body positions or by applying provoking maneuvers. Wile in upright position the hernia reduced back into the abdominal cavity, and a normal anatomical configuration is seen. In extreme cases the whole stomach can be herniated into the mediastinum and rotates 180 degrees alongside the esophagus, which is also called the upside-down stomach sign.

163 Fig.17.: Radiographic image: Axial hiatus hernia. No gastric air bubble could be found in the regular subdiaphragmatic position. The gastric fundus and the cardia can be localized above the diaphragm. High grade reflux is detected in supine position.

Gastric neoplasm

Classification of gastric tumors:

 benign (polyp, adenoma, leiomyoma, fibroma, neurofibroma)

 semimalignant (villous polyps, papillary adenoma)

 malignant (gastric carcinoma)

Classification of malignant gastric tumors according to their gross appearance (Bormann classification):

 I. Polyp like: sharply demarcated polyp like carcinoma (cauliflower like filling defect)

 II. Superficial: sharply demarcated ulcerating carcinoma, polyp like, with intraluminal contrast collection due to necrosis (favorable prognosis, usually in the antrum, the center can be digested and disappear forming a bowl shaped lesion with a 5-8 mm wide collar)

 III. Excavated: poorly circumscribed ulcerating carcinoma (invasion front on the circumference, could not be sharply demarcated from its surroundings)

 IV. Infiltrating: diffusely infiltrating carcinoma (in an extensive disease it can

completely infiltrate the gastric wall – linitis plastica (carcinomatous shrinking of the stomach) aka. scrirrus.

Clinical presentation: In an early stage symptoms are vague including abdominal discomfort and fullness. Loss of appetite, later disgust from meat is experienced. Weight loss, nausea, occasionally bloody emesis are also seen.

The radiographic picture is quite variable. Often a concomitant gastric wall deformity is detected. Frequently, the tumor arises in the antrum. Lesions protruding into the lumen appear as shadows of lost luminal filling. In advanced cases the whole stomach is deformed, with luminal narrowing. The gastric wall is stiffened progressing into a gastric emptying disorder by time.

A distinct form of gastric cancer is linitis plastica or scirrhus. The clinical symptoms are identical with those are seen in other types of gastric carcinomas. However, it is associated with characteristic radiographic and microscopic features.

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Fig.18.: Scirrhus

Radiographic findings: Generally, the lesion starts in the antrum. In the beginning it does not produce any overt symptoms other then parietal stiffness, until the infiltrative tumor spread remains confined to the gastric wall and does not involve the mucosa. Endoscopy can suggest altered wall motility. This can be verified on the upper GI series. The affected wall segment does not show peristaltic activity. The relief of the lesser curvature has a serrated appearance, and wall stiffness could expand to the entire stomach. The stomach morphology transforms into a tube like configuration, while the gastric size is shrunken.