TOPIC : SMALL INTESTINE SERIES

What is the Small Intestinal Series?

A special radiographic examination of the small intestine after administration of positive contrast media.

What part of the digestive system absorbs most nutrients into the bloodstream?

The small intestine.

Where is the small intestine located in the gastrointestinal tract?

Between the stomach and the large intestine.

How do nutrients enter the bloodstream from the small intestine?

Through diffusion via the villi.

What are villi?

Fingerlike projections on the walls of the small intestine that absorb digested nutrients.

What does the Latin word "villus" mean?

Shaggy hair.

What is the function of villi?

To absorb the products of digestion and increase the surface area for absorption.

What is a lacteal?

A lymphatic vessel in the small intestine that absorbs digested fats.

How many main structural parts make up the small intestine?

Three.

What are the three parts of the small intestine?

Duodenum, jejunum, and ileum.

How long is the duodenum?

About 26 cm or 9.84 inches.

How long is the jejunum?

About 2.5 meters or 8.2 feet.

How long is the ileum?

About 3.5 meters or 11.5 feet.

What is the approximate total length of the small intestine in adults?

About 7 meters or 23 feet.

Why is it called the “small” intestine?

Because its diameter is smaller than that of the large intestine.

What is the average diameter of the small intestine?

About 2.5–3 cm.

What is the average diameter of the large intestine?

About 7.6 cm.

What are plicae circulares?

Wrinkled folds covering the small intestine.

What projects from the plicae circulares?

Microscopic fingerlike villi.

Where does the majority of nutrient absorption occur?

In the jejunum.

Where is iron absorbed in the small intestine?

In the duodenum.

Where are vitamin B12 and bile salts absorbed?

In the terminal ileum.

How are water and lipids absorbed in the small intestine?

By passive diffusion.

How is sodium absorbed?

By active transport.

How are glucose and amino acids absorbed?

By co-transport.

What are the three ways of administering barium sulfate?

By mouth, by complete reflux filling, or by direct intestinal tube injection.

What is Enteroclysis?

A fluoroscopic X-ray of the small intestine with contrast infused through a tube inserted into the duodenum.

Where is the enteroclysis tube inserted?

Through the nose, throat, and stomach into the small intestine.

What is the purpose of enteroclysis?

To demonstrate if the small intestine is normal or abnormal.

What diet should a patient follow before a small intestinal series?

A soft or low-residue diet for two days prior.

What should the patient have for supper before the exam?

A light supper.

What purgative is often given before bedtime?

Castor oil.

Is a cleansing enema required for enteroclysis?

It is optional.

When should the patient start NPO?

At midnight before the exam.

Should the patient eat breakfast before the exam?

No.

What is one objective of the small intestinal series?

To know the anatomy of the small intestine.

What is another objective of the exam?

To study the physiology or emptying time (5–6 hours).

What are some pathologies that can be determined through the exam?

Obstruction, malabsorption, congenital anomaly, or bleeding.

What is an example of an obstructive pathology?

Ileus.

What is ileus?

A disruption of normal propulsive ability of the GI tract without mechanical obstruction.

What is an example of an absorption pathology?

Malabsorption.

What is an example of a congenital anomaly in the small intestine?

Double wall intestine.

What is an example of intestinal bleeding pathology?

Infection or ulceration.

Name some disorders of the small intestine.

Cancer, obstruction, foreign bodies, Crohn’s disease, celiac disease, etc.

What is a bezoar or enterolith?

A calculus or concretion found in the intestines.

What is paralytic ileus?

Hypomotility of the GI tract causing disruption of normal peristalsis.

What radiographic pattern indicates small bowel obstruction?

Dilated bowel loops in a ladder-like pattern.

What is Crohn’s disease?

A chronic inflammatory disease of the intestines, especially colon and ileum.

What is celiac disease?

An immune-mediated disorder affecting the small intestine due to gluten sensitivity.

What is carcinoid?

A type of small intestine tumor involving autoimmunity and abnormal immune responses.

What is Meckel’s diverticulum?

A congenital small bulge in the small intestine present at birth.

What is Gastric Dumping Syndrome?

Rapid gastric emptying where food bypasses the stomach too fast.

What are examples of infectious diseases affecting the small intestine?

Ascariasis and tapeworm infection.

What is mesenteric ischemia?

Injury of the small intestine due to insufficient blood supply.

What is acute mesenteric ischemia?

A sudden onset of small intestine ischemia.

What is chronic mesenteric ischemia?

Gradually developing ischemia over time.

What is short bowel syndrome?

A condition where parts of the small intestine are missing or removed.

What is inguinal hernia?

Protrusion of the intestine through the abdominal wall or groin.

What is the typical barium preparation for the procedure?

33%–50% barium in a glass of water.

What is taken before the barium study begins?

A scout film.

What is the reference point for the scout film?

L1–L2 at the level of the umbilicus.

What size of film is typically used?

14 x 17 inches.

At what time intervals are radiographs taken during the study?

15, 30, 60 minutes, and every hour until the cecum fills.

What is the endpoint of the examination?

When the cecum begins to fill.

What is the common projection used?

AP Recumbent.

Where is the central ray directed for delayed sequence exposures?

2–3 inches above the iliac crest.

Where is the CR directed for early images?

L1–L2.

Why is the patient positioned supine?

To avoid abdominal pressure and prevent overlapping of intestinal loops.

What other advantage does the supine position provide?

Better visualization of the C-loop and retrogastric area.

How can the Small Intestinal Series be modified to shorten the exam?

By giving the patient ice-cold water to drink.

What is another way to hasten barium transit?

Allow the patient to walk inside the department.

When should the patient walk during the study?

When barium reaches the cecum.

What medication may be used to relax the intestine during a complete reflux exam?

Glucagon.

What medication may be used to reduce discomfort?

Diazepam (Valium).

What device is used for the complete reflux exam?

Retention enema tip.

How is the barium suspension administered in a reflux exam?

Allowed to flow until seen in the duodenal bulb.

What percent barium suspension is commonly used for reflux?

About 15% ± 5% w/v.

How much barium suspension is needed?

About 4500 mL.

What should be done after the colon is filled with barium?

The enema bag is lowered to drain the colon.

What is Enteroclysis procedure used for?

To examine the small bowel by injecting contrast directly into the duodenum.

At what rate is barium given during enteroclysis?

Approximately 100 mL per minute.

Where is the enteroclysis catheter advanced to?

The end of the duodenum near the ligament of Treitz.

What is used to fill the retention balloon?

Sterile water or saline.

What images are taken during enteroclysis?

Spot images with and without compression.

What may be injected after barium during enteroclysis?

Air.

When is the intubation method used?

In special cases such as obstruction.

What tube is used in the intubation method?

Miller-Abbott tube.

How is the Miller-Abbott tube inserted?

Through the nose down to the obstruction point.

What is the purpose of aspirating in the intubation method?

To locate the exact obstruction site.

What are the common projections used after fluoroscopy?

AP, PA, oblique, and lateral.

In what positions may images be taken?

Recumbent and upright.

What should be shown for proper collimation?

Entire small intestine on each image.

What should be visible on initial images?

The stomach.

What should be included on all images?

Time marker and vertebral column centered.

How should the patient appear in the images?

Without rotation.

What exposure technique should be used?

One that clearly shows small intestine anatomy.

When is the examination complete?

When barium reaches the cecum.

What are gastrointestinal tubes used for?

Feeding or decompression after digestive surgery.

What is a Nasogastric (NG) tube?

A feeding tube used for patients who cannot swallow normally.

What are other types of GI tubes?

Nasointestinal (NI) and Nasoenteric (NE) tubes.