Editing Pathophysiology of Urinary Tract Obstruction (section)

== Answers ==

# What are the phases of a renal scan? Which is the most sensitive indicator of renal dysfunction?
## Flow (initial), renal, excretion
## Renal
# Which nuclear scan is preferred to assess renal scarring? Obstruction? GFR?
# What T1/2 on a nuclear scan is considered non-obstructed vs. obstructed?
# What are reasons for a false-positive renal scan?
# What are limitations of a low-dose CT scan?
# What are the phases of a renal scan?
# Describe the changes that occur in renal blood flow, ureteral pressure, and GFR in unilateral and bilateral urinary obstruction
# What are advantages of a nephrostomy tube of ureteral stent?
## Superior drainage, especially if the fluid is more purulent, due to larger caliber
## Tubes can be irrigated to prevent clogging
## Urine output of the kidney can be measured
## Excessive ureteral manipulation can be avoided, decreasing the risk for sepsis or rupture
## Can be done using US guidance with local anesthesia and conscious sedation, eliminating the need for an anesthesiologist and ionizing radiation exposure
# What is the definition of post-obstructive diuresis? What mechanisms contribute to its occurrence?