Kidney crystals can in some cases heal on their own. Kidney crystals are crystals in the renal calyces that have not yet formed kidney stones, or very tiny kidney stones that have the potential to pass out of the body on their own. Often kidney crystals are detected by ultrasound or CT during a physical examination and usually do not require treatment. When you drink a lot of water or exercise vigorously, the kidney crystals may fall into the ureter and expel on their own, so the kidney crystals can heal on their own. Patients who do not drink a lot of water or sweat a lot may not heal themselves, but may have a further accumulation of kidney crystals and form larger kidney stones. Therefore, in addition to treatment, prevention of kidney stones is also important, such as drinking plenty of water and eating less vegetables that contain more oxalates, such as spinach and celery.