67 terms

Large Intestine

reviews the large intestine, its anatomy and its radiographic positioning.
cecum, colon, rectum, anal canal
name the 4 parts of the Large intestine
about 5 feet, 1.5 meters
what is the length of the L.I.?
taeniae coli
external band of of longitudinal muscle that forms 3 thickened bands
series of pouches in the LI
reabsorption of fluids and elimination of waste products
main function of LI
pouch like portion of the LI below the junction of the ileum and the colon
vermiform appendix
what is attached to the posteromedial side of the cecum?
ileocecal valve
what is just below the junction of the ascending colon and the cecum?
ascending, transverse, descending and sigmoid portions
what divisions are there in the colon?
right colic flexture, or hepatic flexture
what colic flexture is under the liver?
transverse colon
what is the longest, most moveable part of the colon?
left colic flexture, or splenic flexture
what colic flexture is under the spleen?
superior aperture of the lesser pelvis
at what point does the descending colon junction with the sigmoid portion?
sigmoid (think s for sigmoid)
what portion of the colon makes an s shaped loop and ends at the rectum?
3rd sacral segment
what level is the start of the rectum?
what is the terminal aperture of the large intestine?
rectal ampula
what amupula (dilation)is just above the anal canal?
rectum and anal canal
what structures have two ap curves?
hypersthenic patients
what type of patient has L.I. around the periphery of the abdomen and may require more radiographs to show its entire length?
asthenic patients
what type of patient has L.I. which is bunched together and positioned low in the abdomen?
single contrast
L.I. radiographic procedure in which the colon is examined with a barium solution or iodine solution only
two stage double contrast
colon is examined with a barium suspension and then immediately following evacuation, the colon is examined with air enema or another gaseous enema
single stage double contrast
the fluoroscopist selectively injects barium suspension and gas
positive contrast media
reveals anatomy and tonus of colon and most of the abnormalities to which it is subject
gaseous media
serves to distend the lumen of the bowel and render it visible, through the transparency of its shadow, all parts of the barium-coated mucosal lining of colon and any small intraluminal lesions
computed tomography colonoscopy (same as vc) in 3d and multiplanar views
virtual colonoscopy, used as a screening tool for colorectalcancer after a failed conventional colonscopy. (also called ctc)
multiplanar reformatted view
high density barium sulfate
absorb a greater percentage of radiation, particularly useful for double contrast studies, in which uniform coating of the lumen is required
more rapidly absorbed than nitrogen in regular air when evacuation of the gaseous medium is incomplete
why is carbon dioxide used in air contrast studies?
iodized contrast media
what is used when colon perforation or leak is suspected(selectively used when retrograde filling with barium is impossible or contraindicated)
evacuation is often insufficient for double contrast visualization of the mucosal pattern
what is a disadvantage of using iodized contrast solution?
oral admininstration of iodine allows for satisfactory examination of the colon
what is an acceptable use of iodine for uncoperative patients for colon exams?
3-4 hours (fast)
what is transit time from ingestion to colonic filling?
iodized solutions are practically nonabsorbable
what allows oral dose of iodized contrast to outline the entire large bowel?
barium sulfate suspension
what ingested contrast solution is subject to drying, flaking and uneven distribution in the colon?
L.I. must be completely empty of contents to not be confused with polypoid or tumor masses
what is agreeable for preping L.I. Examination by all profesionals?
clear liquids only, and bowel cleansing regimen
what bowel prep is done?
complete intestinal tract cleansing kits, gastrointestinal lavage preparations, cleansing enema
methods of of bowel cleansing
smaller caliber rectal catheter
what should be used on patients who have inflamed hemorrhoids, fissures, a stricture or other abnormalities of the anus?
90 ml
what is the recommended limit on the air capacity for inflatable tips?
one complete squeeze
what provides adaquate distention of the retention balloon without danger of overinflation?
3 quarts
what is the capacity of most enema bags when completely filled?
6 feet long
what is the tube length for enema bags?
500 ml
what is the capacity for smaller enema bags with short, large diameter tubes for double-contrast BE procedures?
12% to 25% weight/volume ratio
What concentration of Barium sulfate is recommended for single contrast colonic enemas?
75%-95% weight/volume ratio
What concentration of Barium sulfate is recommended for double contrast colonic enemas?
85-90 degrees F
If warm BE are administered what temp should it be? (below body temp)
damaging to tissues, causes irritation and difficult or impossible for patient to hold for examination
what happens if BE solution is too warm?
Duodenum quadrant locations
jejunum quadrant locations
Ileum quadrant locations
ileocecal valve quadrant location
PA and or AP, RAO,LAO, LPO and or RPO, lateral rectum, right and left lateral decube, (double contrast)PA post evac
BE series basic order
Ap axial, or ap axial oblique, PA axial or PA axial oblique
Special enema series
welin method
barium introduced to left colic flexure, then tip removed and patient evacuates,tip reinserted and barium introduced to sigmoid and air instilled, position altered to coat mucosa, spot radiographs taken as needed
closed system in which patient remains on table for entire procedure
does not require removal and reinsertion of enema tip
single stage closed system method
barium introduced by bag position, air introduced by bag inversion or by manual compression of sphygmoanometer bulb
PA or AP Barium enema
no body rotation, cr to iliac crest
PA axial large intestine
cr angled 30-40 degrees caudad, enters level of ASIS
oblique that best demonstrates right colic flexure, ascending colon, and sigmoid
obliqe that best demonstrates left colic flexure and descending colon
pa oblique large intestine
35-45 degree RAO or LAO, cr to iliac crest, and 1 inch from msp
ap oblique large intestine
35-40 degree lpo, rpo, cr to iliac crest, 1 inch lateral to elevated side of msp
AP axial large intestine
supine, IR centered 2 inches above iliac crest, CR angled 30-40 cephalic, entering inferior margin of pubic symphysis
Ap axial oblique L.I.
LPO rotate 30-40 degrees, 30-40 degrees cephalic. ONLY position with body rotation and tube angle
PA axial, and Pa Axial oblique
RAO rotate body 35-45 degrees, 30-40 caudad, cr at level of asis, and msp