Takahashi et al used unenhanced helical CT scans to identify factors associated with passage of ureteral stones. This can help identify a patient who can be managed conservatively. The authors are from Lyndon B. Johnson General Hospital and the University of Texas Houston.
Parameters:
(1) diameter of stone in mm
(2) perinephric fat stranding (linear areas of soft tissue attenuation in the perinephric space)
(3) perinephric fluid collection (discrete areas of fluid attenuation in the perinephric space)
(4) location in the ureter
Parameter |
Finding |
Grade |
perinephric fat stranding |
none |
0 |
|
mild (few thin strands) |
1 |
|
moderate |
2 |
|
marked (many thick strands) |
3 |
perinephric fluid collection |
none |
0 |
|
1 or 2 small (< 1 cm) |
1 |
|
more than 3 small or less than 3 large |
2 |
|
3 or more large (>= 1 cm) |
3 |
Parameter |
Likely to Pass |
Indeterminate |
Unlikely to Pass |
Stone Size |
<= 3 mm |
3.1 - 7.0 mm |
> 7.0 mm |
Fat Stranding |
Grade 3 |
Grade 2 |
Grade 0 or 1 |
Fluid Collection |
Grade 2 or 3 |
Grade 1 |
Grade 0 |
Location |
distal |
mid or proximal |
ureteropelvic junction |
Specialty: Nephrology, Clinical Laboratory
ICD-10: ,