KUB - Abdomen : Patient Supine and Upright
The AP projection of the abdomen is sometimes called as KUB xray, because in this projection the Kidneys, Ureters and Bladder are included in the radiograph. It is also use as a preliminary evaluation radiograph or Scot films for some of special procedure. When an AP Projection of abdomen taken in supine it is also called as Flat Plate Abdomen X-ray. Performing this projection, the patient is either supine or upright position as requested by physician. But the supine position is preferred for most initial examination of the abdomen. Structures demonstrated are the size and shape of the liver, the spleen, and the kidney. Pathology of the abdomen, including the intraabdominal calcifications or evidence of tumor masses, bowel obstruction, neoplasms, calcification, and ascites are seen on radiograph AP view if present.Technical Factor:
KUB Radiograph |
Moving of stationary grid
70 - 80 kV range
Shielding and Respiration:
Use gonadal shieldings on males (also on females of reproductive age, only if such shielding does not obscure essential anatomy as determined by a physician).Suspend respiration at the end of expiration, in this technique the abdominal organs are not compressed.
Before an exposure, allow about 1 second delay after expiration to allow involuntary motion of bowel to cease.
Patient Position:
The midsagital plane of the body is centered to the middle of the table or cassettes if portable xray is used.Arms is place at patient's sides, away from the body to avoid casting of shadow on the radiograph.
For immobilization on patient, a compression band can be use, by placing across the abdomen with moderate pressure.
Supine - AP Projection |
Supine Position Abdomen
Legs are extended and place support under knees to relieve strain.Center the image receptor at the level of the iliac crest and adjust IR to include the symphysis pubis.
Upright Position Abdomen
Let patient stand straight erect and its body weight is distributed equally on its feet.Center the image receptor two (2) inches above the level of the iliac crests or ensure that the diaphragm is included.
If the bladder is to be included on the radiograph, the IR is centered at the level of the iliac crests.
If patient is too tall and a 14 x 17 IR is unable to fit the entire pelvic area, and the bladder is needed on the radiograph, take a second radiograph with a 24 x 30 cm IR and include bladder by placing it crosswise and centered 2 to 3 inches above the upper border of the symphysis pubic if needed.
Part Position:
Center of cassette to level of iliac crest, with bottom margin at symphysis pubis (see note below)No rotation of pelvis or shoulders (check that both ASIS are the same distance from the table top)Central Ray and Collimation:
Perpendicular CR to IR, at the level of the iliac crest for supine position.
For upright position, horizontal CR and 2 inches above the level of iliac crests to include the diaphragm.
Minimum SID of 40inches (100cm)
Collimate closely on sides to skin margins and on top and bottom to IR borders.
Note for Body Habitus: A tall hyposthenic - or asthenic type patient may require two IR place in lengthwise - one is centered lower, to include the symphysis pubis and the other is centered high, to include the upper abdomen and diaphragm.
A broad hypersthenic-type patient may require two 35 x 43cm (14 x 17inches) IR place in crosswise, one centered lower to include the symphysis pubis and the second for the upper abdomen, with a minimum of 3 to 5 cm (1 - 2 inches) overlap.
Radiographic Criteria: AP & PA Projection : Upright and Supine Position
The optimal radiograph of an AP projection Abdomen, are stated in the following.A clear demonstration of the area of symphysis pubic to the upper abdomen. Tall patients can be taken 2 radiographic images if needed.
Proper Patient Positioning and Instructions:
Vertebral column is in the middle of image. Ribs, pelvis and hips is equidistant to the sides of the radiograph on both ends.Spinous processes in the center of lumbar vertebrae, and symmetric appearance of the ischial spines of the pelvis (if visible), and alae or wings of the ilia.
No motion of diaphragm on the upright position.
Crosswise position of IR is appropriate for a very big patients.
Correct Exposure Factor and Proper Marker Placement
Soft tissue gray tones of radiograph should demonstrate following: The lateral abdominal wall and properitoneal fat layers, Psoas muscles, lower border of the liver and kidneys, Inferior ribs and the transverse processes of the lumbar vertebrae.Radiographic markers such as, patient ID, number, date and right or left marker is visible and not superimposed over the abdominal contents.
Density on the upright abdomen radiograph is similar to supine radiograph.
Upright radiograph is identified with an appropriate marker.