RDSC 233

Unit 1 Plain Film Radiography of the Abdomen

Bontrager pp. 98-116 Anatomy seen on the plain abdomen radiograph Radiographic anatomy

Positioning of: Plain film abdomen (KUB), flat and: Upright abdomen Left lateral decubitus abdomen Dorsal recumbant (Rt or Lt) Maternal abdomen

Film Critique Exposure Factors Radiographic Pathology What in the World?

Miscellaneous, but significant, odds and ends

Atlas of Human Anatomy Third edition (260) +

Need to know

Four quadrants intersect umbilicus (RUQ, LUQ, RLQ, LLQ) Nine regions Right hypochondriac Right lumbar Right inguinal (iliac) Epigastric Umbilical Pubic (hypogastric) Left hypochondriac Left lumbar Left inguinal (iliac)

Atlas of Human Anatomy Third edition (260)

Need to know

Seven landmarks Iliac crest Anterior superior iliac spine (ASIS} Pubic symphysis Greater trochanter Xiphoid tip (T9-T10) Inferior costal margin Ischial tuberosity

+

Atlas of Human Anatomy Third edition (245)

Need to know

Peritoneum Falciform ligament Diaphragm Transversus abdominis M.

* Internal & external oblique M.

* * Muscles of the flank stripe

Atlas of Human Anatomy Second edition (266)

Need to know

Abdominal viscera

Kidneys Adrenal (suprarenal) glands Pancreas (head, body, tail) Duodenum Rectum Bladder Esophagus Aorta (left sided) Inferior vena cava (right sided)

Atlas of Human Anatomy Second edition (301)

Need to know

Liver Gallbladder & bileducts Stomach Colon (parts of covered in colon unit) Spleen Jejunum and ileum (not shown) Portal vein

What is normally visible Conditions 1. Spleen Y 2. Gallbladder N 3. Stomach Y with gas 4. Veins N 5. Arteries N if calcified 6. Small bowel N gas is pathological 7. Colon (gas) Y with gas 8. Bladder Y with urine 9. Pancreas N 10. Ureters N 11. Kidneys Y 12. Adrenal glands N 13. Flank stripes Y 14. Liver Y

Radiographic Anatomy

Be prepared to identify these anatomical structures in lab.

Radiographic Anatomy of the plain film abdomen A radiograph of the kidneys, ureters, and bladder (KUB) demonstrates the: 1. Size 2. Shape 3. & Position of some, but not all the organs in the abdominal & pelvic cavities.

Why (in two words or less,) is it difficult to differentiate abdominal organs, and not possible to visualize others at all?

Subject Contrast An old term was “flat plate of the abdomen”

Radiographic Anatomy of the plain film abdomen What is

normally

visible 1. Liver 2. Spleen 3. psoas muscles 4. kidneys 5. flank stripes 6. bone (like crazy) 7. Calcifications What is

sometimes

visible 1. Stomach and colon (gas) 2. Bladder (urine filled) 3. Arteries (calcified aorta) What is

not

visible 1. Gallbladder 2. Pancreas 3. Small bowel (unless pathological, with gas) 4. Ureters 5. Adrenal glands 6. Veins 7. Everything else

Radiographic Anatomy of the plain film abdomen Liver (homogeneous shadow in RUQ) Spleen Stomach (c gas) Parts of colon (c gas) hepatic flexure transverse colon cecum & ascending colon Gas, though natural, is a negative contrast media . In the history of radiography, gas (air) was injected in the bladder and ventricles of the brain.

Carbonated soda is given to children to create a “window” to the kidneys

Radiographic Anatomy of the plain film abdomen

More Gas Patterns

Entire colon, from cecum to sigmoid, filled with gas.

Unless obstructed , distention of this degree should be relieved by flautulence A child’s stomach and colon filled with gas and feces, (speckled appearance). Note how the hepatic flexure and transverse colon define the liver Gas filled transverse colon demonstrating haustrations.

Detail of liver in RUQ Radiographic Anatomy of the plain film abdomen Detail of spleen in LUQ

Detail of flank stripe Detail of urine filled bladder Radiographic Anatomy of the plain film abdomen Flank stripes are not always seen due to lack of contrast or clipping on larger persons. When visible, bowing of the stripes may be a sign of a mass .

The bladder is often seen, if contrasted by urine.

Gas in the sigmoid colon may obscure it

Radiographic Anatomy of the plain film abdomen Kidneys Subject contrast of the kidneys is enhanced by the perirenal fat capsule. They are best seen in the asthenic body habitus = Psoas muscles Placement of Rt marker is less than desirable

Radiographic Anatomy of the plain film abdomen

Calcifications

Calcifications can form in various tissues, and especially fluid filled organs where minerals consolidate. In the plain film abdomen those seen are: Large gallstone in RUQ If not in the RUQ, where else could it be?

* gallstones (calcium not cholesterol) * kidneystones * bladderstones * arteriosclerosis (mostly of abdominal aorta)

Anatomy Review:

Where is it, or, at least, where should it be?

Radiographic Positioning of the Abdomen

Positioning of: AP KUB (flat plate of the abdomen) Upright abdomen seated or standing Left lateral decubitus

including

Film Critique Beginning with the routine KUB

Review the ARRT Standard Terminology for Positioning and Projections

Standard KUB Positioning

But first, when using the bucky

1. Put the tube in detent And leave it alone 2. Align the tube to the bucky (longitudinally) And leave it alone* 3. Put a film in the bucky, mark And leave it alone it, close the tray 4. To position, float the table, move the patient, but don’t disturb steps 1-3 5. Shield When positioning in lab, follow these steps. Someone will critique your efficiency *If views in a routine require angles, do them last if possible.

Standard Abdomen Positioning

Preparation

1. Evaluate the order 2. Greet the patient 3. Take History Plain film radiography of the abdomen may be used to diagnose acute abdomen , or provide preliminary information for further studies. Pertinent Hx includes: Abdominal pain: chronic or acute , location (quadrant or region). Times? (i.e. after eating). Previous hx? Known cause? Bloating, constipation, diarrhea.

4. Remove jewelry, check attire, snaps, pins, NG tubes , etc. 5. Explain the exam in layman’s terms 6. Questions? 7. Set technique

before

positioning

Routine KUB Positioning

Setup

1. 40” SID (relatively standard) 2. Reciprocating bucky 12:1, 16:1 grid 3. 70-80 kVp range 4. 14” x 17” film, lengthwise 5. ID marker at bottom 6. Rt marker above ID marker

Routine KUB Positioning

Positioning

1. CR to iliac crest 2. Entire spine straight 3. No rotation on hips (check ASIS) 4. Arms away from sides (with sheet covering patient, watch for wandering hands) 5. Exposure at end of respiration (hold it)

Film Critique for KUB film

* Patient ID * Rt/Lt, special marker * Contrast & density * Motion * * Artifacts

Clipping: Superior ramus and pubic symphysis must be included.

Rotation: Ala of ilium are symmetrical. Vertebral bodies are vertical (no side bending) and not rotated. * Peristalic activity may create motion of the gas pattern.

KUB Positioning: 2 films method

When the patient is tall, two films used lengthwise may be necessary.

When the patient is wide, two transverse.

Note the overlap as evidenced by the iliac crest

Take first exposure of the pelvis.

After changing films, place finger on top of light field, float table top to the the upper abdomen collimated field overlaps the previous field by 3” or 4” inches.

N

on routine positions: Upright abdomen Left lateral decubitus Dorsal recumbant decubitus

Routine Upright Positioning

Setup and Preparation

Same as supine, expect upright .

And, patient must be in position for at least 5 minutes prior to exposure. Bring by WC if possible 4.

Positioning

1. Same as KUB, but center

top

of film to axilla.

Standard Upright Abdomen Positioning

What (else) does the upright demonstrate?

1. Air-fluid levels in the bowel 2. Free air in the abdomen (peritoneal cavity) under the diaphragm

Residual barium x 3 weeks

3. Ptosis (Change in position) Might a change in technique be called for on the upright?

Standard Upright Abdomen Positioning

Criteria:

In addition to the criteria for a supine KUB, the upright film

must demonstrate lung tissue above the diaphragms and plenty of it.

Visualizing the pelvic cavity to the symphysis is not criteria

Standard Left Lateral Decubitus Positioning

The left lateral decubitus film is done

Flash marker

when the patient is unable to stand or sit.

Sponge Set up/Positioning Same as for the upright, except the grid film is in a film holder (not a reciprocating bucky)

Check the patient’s measurement. Too many double bacon cheeseburgers may make it like this

Lt flank Rt flank A horizontal beam projection to demonstrate free air , and air fluid levels . A left lateral, and only a left lateral , is the decubitus position because of the air bubble that is normally in the stomach

Standard Left Lateral Abdomen Positioning

What’s the big deal with the stomach bubble?

To evaluate free air, it is important

to not have

stomach bubble under the flank stripe.

the

Rt side

Criteria: Mid portion of the abdomen, along the flank (not symphysis or diaphram) visible.

Iliac crest Stomach bubble

Dorsal decubitus (Rt or Lt) Abdomen Positioning The dorsal decubitus film is done when that Flash marker position is all the patient is able to tolerate, or for evaluation of the aorta in arteriography

CR Sponge Set up/Positioning

Same as for the decubitus

A horizontal beam projection to demonstrate free air , and air fluid levels . In the dorsal decubitus position free air layers out under the anterior abdominal muscles. Air fluid levels, and the abdominal aortic aneurysms may be seem, but due to part thickness, this projection is not optimal.

Review of Abdomen film Critique

The KUB film must demonstrate all anatomy within the abdominal cavity The upright, left lateral decubitus, and dorsal decubitus positions demonstrate free air, and air-fluid levels.

The upright also demonstrates ptosis of the abdominal organs.

On all films Patient ID Rt or Lt marker Contrast & density Motion Artifacts

Exposure Factors

From the “Rules of Thumb” Based on: 3 phase, 100 RS film, 12:1 grid, 40” SID Abdomen/Pelvis Frontal (2 x cm) + 35 =kVp @ 50 mAs Lateral (4x frontal) (AP + 10 kVp @ 100 mAs Oblique (AP + 40% - 60% of frontal technique

Exposure Factors

From the “Rules of Thumb” Based on: 3 phase, 100 RS film, 40” SID Maternal Abdomen On occasion a radiograph of the pregnant abdomen is ordered during labor, to check for a breech presentation.

Every radiology department should have at least one high speed film/screen system for this purpose.

What is required in terms of kVp and mAs?

High kVp (110 or higher), low mAs.

Exposure Factors

From the “Rules of Thumb” Based on: 3 phase, 400 RS film, 40” SID Calculate a maternal abdomen technique for a 35 cm measurement 1. (2 x 35) + 35 = 105 kVp @ 50 mAs 2. 40 mAs / 4 = 12.5 mAs (film speed) 3. 15% of 105 = 16.5 = Answer 121 kVp @ 6 mAs Critique critera: For presentation, only gross anatomy need be visualized. Maternal abdomen films are rarely repeated.

Significant Pathologies or Pathologic Indicators of the abdomen and their Radiographic Appearances Mass Institutional colon Pneumoperitoneum Ascites Ileus

An example of how the knowledge of the normal size, shape, and position of abdominal anatomy is used to diagnose disease on a KUB.

This film demonstrates a bowing of the right psoas muscle, and increased opacity. The diagnosis was abdominal aortic aneursym (AAA), unusual in that it is on the right, rather than the left, where the aorta is.

Another example: size, shape, or position.

10 cm mass on the right of midline In the right lumbar region

Normal variants

If a mass is not pathologic, it may be an anomaly.

The detail in this LUQ shows anatomy not normally seen there. Lateral to the kidney, only the stomach, spleen, and colon are expected possibilities.

The radiologist determined this to be the “tongue” of the liver (long tip of left lobe), interposed between the spleen and splenic flexure

Institutional Colon Fecal stasis or fecal impaction are terms that describe what is commonly called constipation.

Institutional colon in found in bedridden, elderly patients, whose eliminations have not been monitored

Pneumoperitoneum Diaphragm

Air in the abdominal cavity, (outside of the alimentary tract) comes from perforated viscus, a puncture wound, or recent surgery.

Gastric or duodenal ulcers can perforate and allow air and stomach contents to escape, leading to peritonitis

Liver Stomach In the upright position free air layers out under the diaphragm. Large quantities may be obscured if the top of the film is not high enough. Free air Stomach bubble

Ascites Fluid accumulation in the abdominal cavity, secondary to serious disease.

Ascites creates a gray, low contrast effect, and as in this film, may make gas in the bowel look trapped, or encased by the extrinsic pressures from the fluid.

Ileus x

An ileus is a failure of intestinal contents to move through the bowel, for reasons catagorized as Mechanical ileus: caused by a physical obstruction such as a tumor, adhesions , volvulus (twisting) intussusception (telescoping), or hernia .

Dynamic ileus: muscular constriction Adynamic ileus: lack of motility , paralytic Gallstone ileus Postoperative ileus

High grade mechanical obstruction. Gas avoids pelvis indicating possible mass.

Gas in the stomach, normal from is relieved by eructation . aerophagia Gas in the colon, , normal from the action of e-coli, is relieved by flatulence . Gas in the small intestine is pathological.

Ileus Gas in the colon, normal from the action of e-coli, is relieved by flatulence . Gas in the small intestine is pathological.

Mild to moderated ileus. In addition to distention of the colon, note the gas pattern in the small bowel

What in the World?

Miscellaneous, but significant, odds and ends

What in the World?

Identifying ingested or inserted foreign bodies are another use for the KUB film

What in the World?

Badmitton champion presents with abdominal pain.

This Greenfield caval filter is in the inferior vena cava for the purpose of catching clots from leg veins. If the filter were not present, clots would travel to the right heart, pulmonary artery, and the arterioles of the lungs, causing pulmonary embolism.

(Kidding about the badmitton)

What in the World?

There is something odd about the gas pattern In the area of the sigmoid colon And it’s shaped like a tooth brush holder

What in the World?

Is this Melvin the Moonman, or...

A Cheese Whiz jar UTB

What in the World?

Illustration from “The Compete Idiot’s Guide to Home Medical Treatment,” or what?

The End

1 2 4 5 7 8 3 6 9

Quiz 1 Name the 9 regions of the abdomen and pelvis

What can be visualized 10. Spleen 11. Gallbladder 12. Adrenal glands 13. Stomach 14. Veins 15. kidneys 16. Colon (gas) 17. bladder 18. Pancreas 19. Ureters Y ( if needed to see) or N Gas? Urine?

Liver Y N N Sm. Bowel Y Y N