Abdomen (x-ray and fluoro) Flashcards
AP Abdomen (Supine and Upright) Positioning
- 14 x 17 IR crosswise for bigger patients, lengthwise for smaller patients
- collimate to 1” outside of abdominal shadow (if poss)
- CR centered to Iliac Crest (supine) or 2” above Crest (upright)
- if high and low are needed, to get bladder center at 2-3” above superior pubic symphysis
- expose on expiration to decompress abdominal organs
AP Abdomen (Supine and Upright) Image Eval
- all of abdomen from pubic symphysis to bottom of the diaphragm (2 images needed for large pt)
- kidneys, ureters, and bladder most important
- no rotation
- spinous processes midline
- Alae or wings symmetrical
Why do PA Abdomen (Upright)?
Where to center?
- only done if kidneys are not of interest
- done PA to reduce gonadal dose
- center 2” above crest
- same image criteria
Left Lateral Decubitus Abdomen
Positioning
- done in place of upright abdomen
- place radiolucent pad under pt
- lie in L Lat Decub for several minutes (air/fluid)
- bring arms above level of diaphragm
- center 2” above iliac crest, perp. to IR
- expose on expiration
Left Lateral Decubitus Abdomen
Image Eval
- if poss, all interperitoneal organs visible
- no rotation
- spinous processes centered
- Alae or wings of the illa symmetrical
Lateral Dorsal Decubitus Abdomen
Positioning & Image Eval
Positioning
-lie on back, arms out of FOV (on chest or above head)
-IR perp. to IR 2” above iliac crest
-elevate pt if neccessary
Image Eval
-all of abdomen (if poss) but definitely the inferior diaphragm
-good for visualization of prevertebral space
Why do Lateral Dorsal Decubitus Abdomen?
- done if patient cannot lie on side or stand
- good for showing air-fluid levels
Esophagus (Fluoro Study)
AP/PA, Oblique, and Lateral
- done recumbent (unless specified)
- positioning for AP/PA and Lateral similar to Chest
- **except center IR at T5-T6
- use RAO or LPO for oblique projections
- 35-40 degrees obliquity (from IR)
- shows esophagus between heart and vertebrae
- include esophagogastric junction
Swallowing Dysfunction Study
- Modified Barium Swallow
- center at C4 (?)
- start AP
- end on Lateral
PA Stomach (Contrast Study) Positioning and Image Eval
- center halfway between vertebral column and lateral border of abdomen
- Prone:
- center IR (and CR) at the MSP at L1-L2, 1-2” above lower rib margin
- Upright:
- center 3-6” lower than L1-L2
- b/c stomach drops lower (esp. in asthenic pt)
Oblique Stomach (LPO vs. RAO) Positioning
- Pt recumbent
- LPO oblique 40-70 degrees, more for hypersthenic
- RAO oblique 30-60 degrees, 45 for sthenic
- center IR at 1-2” above lower rib margin
- halfway between midline and lateral border of abdomen
Oblique Stomach (LPO vs. RAO) Image Eval
- PA Obl. RAO shows pyloric canal and duodenal bulb filled with barium
- and air in fundus
- AP Obl. LPO shows fundus filled with barium
- air and little barium in pyrolus
AP Stomach
Positioning
- pt supine
- if very thin, tilt table in Trendelenburg position (head titled back) to fill the fundus
- center IR at halfway between lower rib margin and xiphoid tip, and halfway between lateral margin of abdomen and MSP
AP Stomach
Image Eval
- fundus filled with barium
- double-contrast delineation of stomach body, pylorus, and duodenum
- lower section of lung field
Why do AP Scout for Barium Stomach studies?
used to check for calcifications or tumor masses of the spleen, liver, kidneys, psoas muscles, and bony structures. standard AP supine abdomen (?)
R Lateral Stomach
Positioning
- true lateral pos. (MCP perp. with IR)
- IR centered midway between MCP and anterior surface of abdomen
- IR centered at 1-2” above lower rib margin (L1-L2) or
- L3 for upright
R Lateral Stomach
Image Eval
- R Lat good for visualization of:
- right retrogastric space
- duodenal loop and duodenojejunal junction
- most importantly, the pyloric canal
- no rotation of pt shown by vertebral column
PA Scout Small Bowel
- on belly to compress abdominal contents
- IR centered at L2 (1-2” above lower rib margin)
- IR centered at MSP
PA Small Bowel Follow Through
- take PA images every 15-30 minutes until barium reaches iliocecal valve
- IR center at level of iliac crests, MSP
Centering Point for all Large Intestine Exams (NOT including Rectum or Axial projections)
-Iliac Crest, MSP for Sthenic pt, higher for Hyper- and lower for Asthenic
What anatomy should be included on all Large Intestine images? (not including Rectum or Axial)
- all of the colon including flexures
- may need two images for Hypersthenic pt
Where are air and barium located in a PA Large Intestine image?
- air is in ascending and descending colon
- barium is in transverse colon
For Large Bowel:
PA Obl RAO and AP Obl LPO both show what anatomy?
- ascending colon
- cecum
- sigmoid colon
- center 1-2” from midline towards the elevated side
For Large Bowel:
PA Obl LAO and AP Obl RPO both show what anatomy?
- descending colon
- left colic flexure
- center 1-2” from midline towards the elevated side
