Radiolucent stone is
(Uric acid calculus) (1317-LB) (1296-B &L 25th)* About 90% of calculi are radiopaque (calcium, phosphate oxalates, cystine)* Uric acid stones are radiolucent and appear on an excretion urogram as a filling defect* Spiral CT has become the study of choice in emergent situations, as the entire urinary tract can be scanned rapidly and without contrast injection. (1042-CSDT 11th)
Oxalate calculus
Phosphate calculus
Uric acid calculus
Cysteine calculi
Kidney & Ureturs