Kidney Stone Scoring

STONE Nephrolithometry Score is a medical app designed to help urologist to categorize kidney stone before performing percutaneous nephrolithotomy (PCNL) procedure. The higher the score is, the more complex the PCNL procedure will be. The S.T.O.N.E. nephrolithometry scoring system was introduced by the Smith Institute for Urology. This scoring system is based solely on 5 parameters obtained from preoperative NCCT. These parameters include Stone size (mm2), Tract length (mm), hydronephrosis or Obstruction, Number of involved calyces, and stone density or Essence (Hounsfield units, HU). The total S.T.O.N.E. nephrolithometry score ranges from 5 to 13, with 13 representing the most complex PCNL and 5 representing the simplest PCNL. The S.T.O.N.E. score successfully predicts post-PCNL stone-free status.

All calculations must be re-checked and should not be used alone to guide patient care, nor should they substitute for clinical judgment. Calculations in this app might be different with your local practice. Consult to expert doctor whenever necessary.

Disclaimer: please seek a doctor’s advice in addition to using this app and before making any medical decisions.