PA SMALL BOWEL SERIES

POSTEROANTERIOR (PA) PROJECTION SMALL BOWEL SERIES

Pathology Demonstrated

• In PA Small Bowel Series Pathology demonstrates are Inflammatory processes, neosplasm, and obstructions of the small intestine are shown.
• Upper GI small bowel combinations are commonly done by additional barium is ingested after completion of the upper Gastrointestinal (GI)

Procedure Summary for Upper GI Small Bowel Combination:
Basic Procedure:

• Routine Upper Gastrointestinal (GI) first
• Notation of time patient ingested first cup 8oz of barium
• Ingestion of second cup of barium.
• 30 minutes PA radiograph (Centering high for proximal Small Bowel (SB)
• Half hour interval radiographs, centered to iliac crest, until barium reaches large bowel usually 2hrs.
• 1 hour interval radiographs, if more time is needed after 2 hrs.

Optional Preparation for Upper GI small bowel:

• Fluoroscopy and spot imaging if ileocecal valve and terminal ileum and compression cone may be used.
• Small Bowel only Series: Includes scout abdomen radiograph followed by ingestion of barium mixture and timed interval radiograph see Procedure Summary below

Procedure Summary of Small Bowel only Series
These are the Basics:

• Plain abdomen radiograph also known as Scout film.
  2 cups (16 oz) of barium ingested (noting time)
  15 to 30 minute radiograph ( centered high for proximal Small Bowel)
• Half hour interval radiograph (centered to crest) until barium reaches large intestine or large bowel it is usually takes 2hrs.
• 1 hour interval radiographs, if more time is needed, because some routines including continuous half hour intervals.

Optional Preparation for Small Bowel Series:

• The use of fluoroscopy with compression sometimes required
• Enteroclysis and Intubation Procedures
• A third method of small bowel study is the enteroclysis procedure, which is a double contrast method that is used to evaluate the small bowel
• Procedure Summary for Enteroclysis (Double Contrast Small Bowel Series)

Procedure:

• Special Catheter advanced to duodenojejunal junction.
• Thin mixture of barium sulfate instilled.
• Air and methylcellulose instilled.
• Fluoroscopic spot images and conventional radiographs taken.

Optional:

• Patient must be taken to Computed Tomography for scan of GI tract.
• On successful completion of exam, intubation tube removed.
• Technical Factors in PA Small Bowel Series:
• Image Receptor size 35 x 43 cm or 14 x 17 inches, lengthwise
• Moving or stationary grid
• 100 to 125 kV range
• Time markers to be used

Technique and Dose:

• mAs 4
• PA: 30 minutes SB

PA 30 minutes - centered approximately 2 inches above iliac crest

Shielding of the Patient:

• Shield gonads only if such shielding does not cover pertinent anatomy.

Patient Position:

• Patient is in prone or supine if patient cannot lie in prone position, with a pillow for the head.

Part Position:

• Align Mid Sagital Plane (MSP) to midline of table/grid and or CR.
• Place arms up beside head with legs extended and support provided under the ankles.
• Ensure that no rotation occurs.

Central Ray

• CR is perpendicular to IR.
• 15 to 30 min: Center to about 2 inches or 5 cm above the iliac crest (see note).
• Hourly: Center CR and midpoint of IR to iliac crest.
• Center the Image Receptor to Central Ray
• Minimu Source to Image Distance (SID) is 40 inches or 100 cm

Collimation:

• Collimate on four sides to outer margins of Image Receptor.

Respiration During Exposure:

• Suspend respiraton and EXPOSE on EXPIRATION.

Note:

• Timing begins with ingestion of barium. Timed intervals of radiograph depends on transit time of the specific barium preparation used and on departmental protocol.
• For First 30 minute radiograph, center high to include the entire stomach.
• Subsequent 30 minute interval radiographs are taken until barium reaches into the large bowel usually 2hrs.
• The study generally is completed once the contrast media reaches the cecum and / or the ascending colon.
• Fluoroscopy and spot imaging of the ileocecal valve and terminal ileum after barium reaches this area are commonly included in the small bowel series routine.
• This procedure, however is determined by the radiologist's preference and by department routines.

Radiographic Criteria for Small Bowel Series:

AP 30 minutes showing stomach and small intestine

Structure Shown for Small Bowel Series:

• Entire small intestine is demonstrated on each radiograph, with the stomach included on the 15 - and or 30 minutes radiograph.

Position:

• No rotation is present. The ala of the ilium and the lumbar vertebrae are symmetric.

Collimation and CR when performing Small Intestine Series:

• Only minimal collimation margins are seen on all four sides for adults.
• CR is centered approximately 2 inches (5cm) above the iliac crest for the the initial radiographs.
• CR is centered at iliac crest for the remaining radiographs.

Exposure Criteria and Markers for Small Bowel Series or Small intestine X-ray:

• Appropriate technique is employed to visualize the contrast filled small intestine without overexposing those parts that are filled only partially with barium.
• Sharp structural margins indicate no motion.
• Patient ID information, time interval markers, and right and left marker are visible without superimposition of essential anatomy.