Renal Stones (Kidney Calculi)
Stones inside the kidney behave differently from ureteric ones: many are asymptomatic, and the decision is often whether to treat at all rather than how urgently.
The big picture
Stones sitting inside the kidney behave differently from stones in the ureter: many are asymptomatic, found incidentally, and the decision is often whether to treat at all rather than how urgently. When they do need treatment, the choice of technique is driven by stone size, location within the kidney, hardness, and anatomy — and the bigger the stone, the more the balance shifts from non-invasive shockwaves toward percutaneous surgery.
The framework: renal stones are often silent; treatment depends on size/location/composition; the three modalities are SWL, flexible ureteroscopy (RIRS), and PCNL, with PCNL for large/staghorn stones; and complete clearance matters for infection stones.
Mechanism pathway
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Diagnostic algorithm
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Board traps
Many renal stones are asymptomatic — observation is reasonable for small, non-obstructing ones.
Treatment choice = size + location + hardness + anatomy.
PCNL is the standard for large (>2 cm) and staghorn stones (highest stone-free rates); access via a posterior calyx.
SWL suits smaller/softer stones; it struggles with large, hard (cystine), or lower-pole stones.
Staghorn/infection stones need complete clearance — residual fragments regrow.