Computational Analysis of Influencing Factors and Multiple Scoring Systems of Stone Clearance Rate after Flexible Ureteroscopic Lithotripsy

Table 1

SSS for renal calculi.

S: stone size, the length × width of the largest cross-sectional area of stone in CT plain scan = cross-sectional area (mm^2)	1 points 0∼399
	2 points: 400∼799
	3 points: 800∼1599
	4 points: ≥1600
T: tract length, the distance measured from the center of stone to the skin on the cross section of CT (horizontal line, 45° line, and vertical line).	1 point: ≤100 mm
	2 points: >100 mm
O: obstruction, degree of hydronephrosis	1 point: no obstruction or mild hydronephrosis
	2 points: moderate or severe hydronephrosis
N: number of involved calices	1 point: 1 renal caliceal involvement
	2 points: 2–3 renal calices involvement
	3 points: complete staghorn calculi
E: essence or stone density	1 point: ≤950HU
	2 points: >950HU