'4' constrictions on ureter

[chuinhen]

normally we study that there is 3 constrictions in the ureter

that is at:

 

1) ureteropelvic junction

 

2) when ureter passes pelvic brim

 

3) when it opens into the urinary bladder

 

 

 

but i heard from an unknown source that there is a 4th constriction

when it crosses the external iliac artery ...

 

is it true ??