Final answer:
Urinary stones smaller than 5 millimeters often pass without intervention, while stones between 5 and 10 millimeters have a 50% chance of passing naturally. Stones larger than 10 millimeters usually require urologic intervention such as lithotripsy or surgery.
Step-by-step explanation:
The size of urinary stones affects their chances of passing through the urinary tract without the need for medical intervention. Small kidney stones tend to pass more readily, with stones less than 5 millimeters in size often having a high chance of passing on their own. Stones that are between 5 and 10 millimeters have about a 50% chance of passing without surgical treatment. Larger stones, typically greater than 10 millimeters, frequently require urologic intervention such as lithotripsy or surgical removal.
Treatments for kidney stones that cause a blockage and do not pass naturally include lithotripsy, where high-intensity ultrasound pulses are used to break the stone into smaller pieces. A ureteral stent may be used to help pass larger stones or when there is a need to relieve a blockage to allow normal urine flow. In some cases, particularly with very large stones that can cause tissue damage or obstruct urine flow, more invasive surgical methods may be necessary to remove the stones directly.