Comparison of percutaneous nephrolithotomy and retrograde intrarenal surgery outcomes for kidney stones larger than 2 cm from Guy's stone scoring system perspective.

SF of PNL in a single session and short operation time seems to be significant especially in GSS grades 1, 2 and 3 category stones. Although the number of patients in the GSS 4 group is very small to claim this, RIRS might be considered as an alternative to PNL in a special group of patients such as GSS grade 4 because of its lower complication rates and shorter LOHS.