Pyelogram (or pyelography or urography) is a form of imaging of the renal pelvis and ureter.[1]
Types include:
Intravenous pyelogram – In which a contrast solution is introduced through a vein into the circulatory system. This is a form of anterograde pyelogram.
Retrograde pyelogram – Any pyelogram in which contrast medium is introduced from the lower urinary tract and flows toward the kidney (i.e. in a "retrograde" direction, against the normal flow of urine).
Anterograde pyelogram (also antegrade pyelogram) – Any pyelogram where a contrast medium passes from the kidneys toward the bladder, mimicking the normal flow of urine.
Gas pyelogram – A pyelogram that uses a gaseous rather than liquid contrast medium.[2] It may also form without the injection of a gas, when gas producing micro-organisms infect the most upper parts of urinary system.[3][4]
