Upper Gastrointestinal System

• Upper Gastrointestinal (1503)

Alimentary Canal

• Consists of the oral cavity (mouth), pharynx, esophagus, stomach, duodenum, small intestine, large intestine, and anus.

Accessory Organs

• Includes the salivary glands, pancreas, liver, and gallbladder.

Functions of the Digestive System

• Intake and digestion
• Absorption
• Elimination

Digestive system functions

• The digestive system functions include ingestion and/or digestion, absorption, and elimination.
• Ingestion and/or digestion involves the oral cavity, pharynx, esophagus, stomach, and small intestine.
• Absorption mainly occurs in the small intestine and stomach.
• Elimination primarily happens in the large intestine.

Liver and Gallbladder

• The Gallbladder is in the RUQ
• The gallbladder is 7-10 cm long and 3 cm wide
• The liver has a right and left lobe
• A hormone(Cholecystokinin) causes the gallbladder to contract
• The gallbladder stores bile, concentrates bile, and releases bile
• The main function of bile is to emulsify fat
• When fats and proteins enter the small intestine, cholecystokinin triggers the gallbladder and pancreas to contract to release bile.

Bile Route

• Bile flows from the right and left hepatic ducts to the common hepatic duct.
• From the common hepatic duct, bile flows to the common bile duct.
• Bile then passes to the pancreatic duct and finally enters the duodenum.

Radiography Procedures

• An Esophogram is a study of the pharynx and esophagus, examining the form and function of swallowing.
• Distance is important for the technologist's role in fluoroscopy.
• An Upper GI series uses barium to study the distal esophagus, stomach, and duodenum.
• Barium sulfate mixed with water is the preferred contrast medium for the alimentary canal.
• Negative density areas on the X-ray, appearing white, show the stomach and duodenum filled with barium sulfate contrast media.

Accessory Organs in the Mouth (Oral Cavity)

• Terms to know: Mastication, Deglutition, Peristalsis
• Location of the Salivary glands: Parotid, Submandibular (submaxillary), and Sublingual

Digestion - Mechanical

• Mechanical digestion includes all movements of the GI tract, starting in the oral cavity (mouth) with chewing, and continuing in the pharynx and esophagus with swallowing.

Mechanical Digestion Summary

• Oral cavity: mastication (chewing), deglutition (swallowing)
• Pharynx: deglutition
• Esophagus: deglutition, peristalsis (waves of muscular contraction in 1-8 sec)
• Stomach: mixing (chyme) peristalsis (2-6hr)
• Small Intestine: rhythmic segmentation (churning) peristalsis (3-5hr)

Chemical Digestion Summary

• Carbohydrates are digested into simple sugars in the mouth and stomach.
• Proteins are digested into amino acids in the stomach and small bowel.
• Lipids (fats) are digested into fatty acids and glycerol in the small bowel only.
• Liver helps to digest Fats

Substances Absorbed but Not Digested

• Vitamins
• Minerals
• Water
• Enzymes digest juices
• Bile emulsifies fats

Esophagus and Stomach

• Fluids pass from the mouth and pharynx to the stomach by gravity.
• Most solid material passes to the stomach both by gravity and peristalsis.
• Peristalsis is a wavelike series of involuntary muscular contractions.
• Food is constricted at the esophageal junction
• Inside the stomach there are Gastric canals and Rugae (mucosal folds)

Stomach

• The stomach is located between the esophagus and the small intestine.
• The Greek word gaster means stomach.
• The stomach stretches.

Chyme

• Once food enters the stomach and is mixed with gastric secretions, it is called chyme.

Stomach Openings & Curvatures

• The Esophagogastric junction (cardiac orifice) is the opening between the esophagus and the stomach.
• The cardiac sphincter allows food and fluid to pass through the orifice.
• A cardiac notch is superior to the cardiac orifice.
• The cardiac antrum is the distal abdominal portion of the esophagus curves sharply into a slightly expanded portion of the terminal esophagus
• The lesser curvature is the medial border of the stomach.
• The greater curvature is the lateral border of the stomach.

Stomach Subdivisions - Pylorus

• The main parts of the stomach are the fundus, body, and pylorus.
• The angular notch is where the large body of the stomach has a partially constricted area separating the body from the pylorus.
• The pyloric orifice (sphincter) is the opening of the distal stomach before entering the duodenum.
• The pyloric antrum is the smaller terminal portion of the stomach, medial to the angular notch.
• The pyloric canal, distal to the angular notch, is a narrow canal towards the pyloric sphincter.
• Fundus is most posterior; Pylorus is posterior/distal to the body

Body Habitus (Stomach and Large Intestine Locations)

• Stomach location classified under hypersthenic, sthenic, and hyposthenic/asthenic body habitus.
• Hypersthenic: The stomach is high and transverse
• Sthenic: J-shaped stomach
• Hyposthenic/Asthenic: J-shaped and low stomach
• Hypersthenic Duodenal bulb/Gallbladder Location: T11-T12
• Sthenic Duodenal bulb/Gallbladder Location: L1-L2
• Hyposthenic/Asthenic: L3-L4
• Hypersthenic Large Intestine location: Widely distributed.
• Sthenic Large Intestine location: Left Colic Flexure high
• Hyposthenic/Asthenic: Low near pelvis

Contrast Media

• There are single-contrast and double-contrast UGI.
• Single-contrast uses barium sulfate.
• Double-contrast uses barium sulfate and carbon dioxide gas or room air.
• Colloidal Suspension never dissolves in water.
• A colloidal suspension is not a solution. It will separate if sitting for a while
• Contraindications for Colloidal Suspension: perforated viscus or presurgical procedure

Barium Sulfate

• Barium sulfate is a positive or radiopaque
• Chalk-like substance that absorbs more x-rays.
• Chemical formula: BaSO4

Barium

• Thick barium has a 3:1 or 4:1 ratio of BaSO4 to water.
• Thin barium has a 1:1 ratio of BaSO4 to water.

Water-Soluble Iodinated Contrast Media

• Indications include Perforated viscus and Presurgical procedure
• Contraindications include Hypersensitivity to iodine

Air-Barium Distribution

• Air is black, and barium is white
• supine Air=fundus and Barium=pylorus
• prone Air=pylorus and Barium=fundus
• erect Air=fundus and Barium=pylorus

Upper GI Series

• NPO (nothing by mouth) for 8 hours, is routine

Upper GI Routine Positions/Projections

• RAO
• PA
• Right lateral
• LPO
• AP

Upper GI Clinical indications

• Workbook 309, question #26:
• Peptic ulcer
• Hiatal hernia
• Diverticula
• Gastritis
• Tumor
• Bezoar

AP Supine Upper GI

• The entire stomach and duodenum are visible, with the fundus of the stomach filled with barium.
• SID= 40 inches
• Use 17 x 14 (Portrait)
• Supine with arms at the side.
• Sthenic body types are centered CR perpendicular to IR to level of L1 (midway between midline and the left lateral margin of the abdomen).
• Hypersthenic body types are centered about 2 inches above L1.
• Asthenic body types are centered 2 inches below L1 and nearer to the midline.
• Expose on expiration
• Optimal KVp Range for Single contrast: 110-125;
• Optimal KVp Range for Double contrast: 80-90

LPO Upper GI

• The entire stomach and duodenum are visible, and the fundus is filled with barium. Pylorus and duodenum are filled with air, double contrast
• SID: 40 inches
• Film size: 10 x 12 (Portrait)
• Rotate 30-60 degrees from supine, with the left side against the board
• Sthenic body types are centered CR perpendicular to IR to the level of L1 (midway between midline and the left lateral margin of the abdomen) 45-degree oblique.
• Hypersthenic body types are centered about 2 inches above L1, 60-degree oblique.
• Asthenic body types are centered 2 inches below L1 and nearer to the midline, 30-degree oblique
• Optimal KVp Range for Single contrast: 110-125;
• Optimal KVp Range for Double contrast: 80-90
• Expose on expiration

Right Lateral Upper GI

• The retro-gastric space is in profile.
• SID: 40 inches
• True Lateral
• Film size: 10 x 12 (Portrait)
• Sthenic body types are centered CR and IR to the duodenal bulb at the level of L1 (lower margin of ribs and 1 ½ inches anterior to the mid coronal plane).
• Hypersthenic body types are centered about 2 inches above L1.
• Asthenic body type: 2 inches below L1
• optimal KVp Range for Single contrast: 110-125;
• optimal KVp Range for Double contrast: 80-90
• Expose on expiration

PA (prone) Upper GI

• The entire stomach and duodenum are visible, with the body and pylorus of the stomach filled with barium.
• SID: 40 inches
• Film size: 17 x 14 (Portrait)
• Supine with arms at the side
• Sthenic body types are centered CR and IR to the level of the pylorus and duodenal bulb at level of L1 and about 1 inch to the left of the vertebral column
• Hypersthenic body types: Center about 2 inches above L1 and nearer the midline
• Asthenic body type: 2 inches below L1
• Expose on expiration
• kVp Range: 110-125
• Use 80-90 for double contrast (positive and negative)

RAO Upper GI

• The entire stomach and C-loop of the duodenum are visible, with the duodenal bulb in profile.
• SID: 40 inches
• Film size: 10 x 12 (Portrait)
• RPO. Rotate 40-70 degrees from prone with the right side against the board
• Rotate more for hypersthenic and less for asthenic
• Sthenic body types are centered CR and IR to the duodenal bulb at level of L1 (1 to 2 inches above the lower lateral rib
• Use 80-90 for double contrast (positive and negative)

Clinical Indications for Esophagogram

• NPO (nothing by mouth) for 4-6 hours
• Clinical indications include anatomic anomalies, esophageal reflux, esophageal varices, foreign body obstruction, and impaired swallowing mechanism.
• Carcinoma of esophagus is also something to consider

Esophagography: Radiographer's Responsibilities

• Prepare fluoroscopy room
• Prepare contrast media.
• Obtain clinical history.
• Explain procedure.

RAO Esophagogram

• Use 35° to 40° oblique.
• Have CR to T5-T6 (1 inch [2.5 cm] inferior to sternal angle).

Evaluation Criteria for RAO Esophagogram

• The entire esophagus is demonstrated.
• The esophagus midway is between the spine and the heart.
• Optimal exposure factors
• Place the patient in RAO to throw the esophagus off of the spine.

Lateral Esophagogram

• Must be a true lateral
• The CR is at T5-T6

Evaluation Criteria for Lateral Esophagogram

• The entire esophagus is demonstrated.
• Esophagus is midway between the spine and heart.
• Arms are not superimposing the esophagus.
• Must be a true lateral.
• There must be optimal exposure factors

Esophagram vs. Upper GI

• Peptic ulcer
• Hiatal hernia
• Diverticula
• Gastritis
• Tumor
• Bezoar
• Anatomic anomalies
• Esophageal reflux
• Esophageal varices
• Foreign body obstruction
• Impaired swallowing mechanism

Quiz Me

• The RAO projection will show the duodenal bulb in profile
• The Right Lateral projection will demonstrate the retrogastric space

General Facts

• ILEUS = Obstruction
• ACHALASIA – Esophagram- Achalasia is a rare swallowing disorder that affects the esophagus.

Radiography Note

• When the Fundus is filled with barium and the pylorus and duodenal bulb are profiled and air filled=LPO