pyelectasis foetal

 Foetal pyelectasis –Dilatation of renal pelvis: Its significance ?? 

Foetal pyelectasis –Dilatation of renal pelvis: Its significance ??

The cut off for Pyelectasis is 4 mm in 2nd trimester & 7 mm in 3rd trimester.

Point 1:  Renal pelvis dilatation is seen in 1 to 5% of foetuses..In 40 to 90% of cases it is transient/ physiological & does not represent any underlying pathology.

 Point 2:-
However, in approximately one third of cases, a urinary tract abnormality, most frequent abnormality is  UPJ obstruction or vesico- ureteral reflux (VUR) which is usually  confirmed in neonatal period .

Point 3: According to the society for Fetal Urology, risk of postnatal urinary abnormality according to the degree of renal pelvis dilatation is as follows:

1) In Second Trimester:

a) Mild dilatation ( 4 to less than 7 mm ) - Risk of postnatal abnormality is 12% :

b) Moderate ( 7 to 10 mm) - Risk is 45% :

c) Severe ( more than 10mm ) - Risk is 88%

2) What about Third Trimester?? : Mild dilatation ( 7 to less than 9mm) - Risk is 12% Moderate ( 9 to 15 mm) - Risk is 45% .,Severe ( more than 15 mm) - Risk is 88% .

What else have to be imaged in USG?? Other findings that suggest pathology include: calyceal dilatation, cortical thinning, or dilatation elsewhere in the urinary tract .