Urinary Procedures

AP PROJECTION (SCOUT AND SERIES): INTRAVENOUS (EXCRETORY) UROGRAPHY

Pathology DemonstratedScout demonstrates abnormal calcifications that may be urinary calculi. After injection, the AP projection may demonstrate signs of obstruction, hydronephrosis, tumor, or infection.

Intravenous (Excretory) Urography—IVU

BASIC

• AP (scout and series) • Nephrotomogram • RPO and LPO (30°) • AP—postvoid erect or recumbent

IVU scout and series.

Technical Factors

• Moving or stationary grid • 70 to 75 kV range • Minute markers where applicable

• IR size—35 × 43 cm (14 × 17 inches), lengthwise; for nephrogram—28 × 35 cm (11 × 14 inches), crosswise

ShieldingShield gonads on males, keeping the shield below the superior margin of the symphysis pubis. Shield both males and females for nephrogram.

Patient PositionSituate patient supine, with pillow for head, arms at sides away from body, and support under knees to relieve back strain.

Part Position• Align midsagittal plane to center line of table and to CR. • Ensure no rotation of trunk or pelvis. • Include symphysis pubis on bottom of IR without cutting off upper kidneys. (A second smaller IR for bladder area may be necessary on hypersthenic patients.)

Central Ray• CR is perpendicular to IR. • Center CR and IR to level of iliac crest and to midsagittal plane. • Minimum SID is 40 inches (100 cm).

CollimationCollimate to IR or smaller if possible.

RespirationSuspend respiration on expiration and expose.Note: Have patient empty bladder immediately before beginning exam so that contrast media in the bladder is not diluted. Explain procedure and obtain clinical history before injecting contrast media. Be prepared for possible reaction to contrast media.

Radiographic Criteria

Structures Shown: • Entire urinary system is visualized from upper renal shadows to distal urinary bladder. The symphysis pubis should be included on lower margin of the IR. • After injection, only a portion of the urinary system may be opacified on a specific radiograph in the series.

Position: • No rotation as evidenced by symmetry of iliac wings and ribcage.

Collimation and CR: • Collimation borders to IR margins on top and bottom to prevent cutoff of essential anatomy. • Complete arch of symphysis pubis visible on bottom margin of radiograph, with center of image at level of iliac crest.

Exposure Criteria and Markers: • No motion due to respiration or movement. • Appropriate technique with short-scale contrast demonstrating the urinary system. • Minute markers and R or L markers visible on all series radiographs.

NEPHROTOMOGRAM AND NEPHROGRAM: INTRAVENOUS (EXCRETORY) UROGRAPHY

Pathology DemonstratedNephrogram or nephrotomogram demonstrates conditions and trauma to the renal parenchyma. Renal cysts and/or adrenal masses may be demonstrated during this phase of the IVU.

A nephrogram involves a single AP radiograph of the kidney region taken within 60 seconds following injection.

Technical Factors• Linear tomography • IR size—24 × 30 centimeters (10 × 12 inches), or 28 × 35 centimeters (11 × 14 inches), crosswise

ShieldingShield gonadal area for both males and females.Patient PositionPosition patient supine, with pillow for head, arms at side away from body, and support under knees to relieve back strain.Part Position• Align midsagittal plane to center line of table/grid. • Ensure no rotation of trunk or pelvis

RPO AND LPO POSITIONS: INTRAVENOUS (EXCRETORY) UROGRAPHY

Pathology DemonstratedSigns of infection, trauma, and obstruction of the elevated kidney are shown. Also demonstrates trauma or obstruction of the downside ureter.

RPO—30°. Inset, 30° LPO

RPO

PostvoidPathology DemonstratedPosition may demonstrate enlarged prostate (possible BPH) or prolapse of the bladder.The erect position demonstrates nephroptosis (abnormal positional change of kidneys).

AP PROJECTION • LPO AND RPO POSITIONS • LATERAL POSITION (OPTIONAL): CYSTOGRAPHY

Pathology DemonstratedSigns of cystitis, obstruction, vesicoureteral reflux, and bladder calculi are visualized. Lateral demonstrates possible fistulas between bladder and uterus or rectum.

Cystography

BASIC• AP (10° to 15° caudad) • Both oblique positions (45° to 60°)

AP (10° to 15° caudad)

Posterior Oblique Positions: • 45° to 60° body rotation. (Steep oblique positions are used to visualize posterolateral aspect of bladder, especially UV junction.)

RPO (45° to 60°).

45°

RPO (30°) POSITION—MALE • AP PROJECTION—FEMALE: VOIDING CYSTOURETHROGRAPHY

Pathology DemonstratedFunctional study of the urinary bladder and urethra determines cause of urinary retention and evaluates for possible vesicoureteral reflux.Voiding Cystourethrography

BASIC• Male—RPO (30°) • Female—AP

Male: • Oblique body 30° into the RPO position. • Superimpose urethra over soft tissues of right thigh.

Female: • Position patient supine or erect into the AP position. • Center midsagittal plane to table or film holder. • Extend and slightly separate legs.