HORSESHOE KIDNEY

Question 1

horseshoe kidney characterized by?
- assoc sx

Answer 1

• abnormalities in position, rotation, and vasc supply of kidney
• assoc w/ ureteric obstruction and impaired urinary drainage

kidneys FUSED together

Question 2

horseshoe kidney types of fusion

Answer 2

• fused at isthmus midline (can be wide or narrow) or laterally

Question 3

horshoe kidneys diff in 3 main ways

Answer 3

• location, orientation, vasculature

Question 4

location

Answer 4

• ascent held back by IMA at L3
• can be found in lower abd and pelvis

Question 5

orientation
- ureters
- isthmus
- complications

Answer 5

during 6-8 weeks development–> renal ascent coupled with 90 degree medial rotation
- isthmus may cause malrotation
- ureters then need to pass over isthmus or down ant surface of kidneys—> cause urinary dranage problems and stasis

Question 6

vasculature
- variations based on what
- complications

Answer 6

• variation of # of renal arteries/veins
• depends where ascent terminated during development
• nl intra renal vasc patterns remains but ligation or divison of any arteries can cause ischemic segmental renal ischemia or necrosis (poor collateral supply)

Question 7

imaging
- definitive dx imaging

Answer 7

Dx- CT or US
- CT MRI best for detecting accessory vasculature and surrounding structures

CT UROGRAM DEFINITIVE DX

Question 8

managing renal cancer in horseshoe kidney

Answer 8

• laparoscopic + robotic techniques
• 3D modeling to improve preop tx and surgical approach (horseshoe more anatomically complex)

Question 9

2 other types of renal fusion abnormality

Answer 9

• crossed fusion renal ectopia
• fused pelvic kidney

Question 10

crossed fusion renal ectopia

Answer 10

• both kidneys positioned on same side of the body with one ureter crossing midline to drain into bladder

Question 11

fused pelvic kidney

Answer 11

single renal mass drained by 2 ureters that do not cross midline