Material Methods
Patients who underwent fURS for kidney and ureteral stones between
January 2017 and January 2020 were retrospectively analyzed. The patient
and stone characteristics and perioperative findings were noted. The
T.O.HO. score was externally validated and compared with the STONE
score. Stone-free parameters were evaluated with the multivariate
analysis. Based on the results of this analysis, the T.O.HO. score was
modified and internally validated.