It can take a few days. Depending on where the stone is and how small it is. Sometimes we monitor up to six weeks, but if the stone isn't progressing, we'll go ahead and take care of it.

If the pain is so much that they can't endure it, then we will go ahead and treat. If their pain is coming and going, and well-controlled with things like ibuprofen or other pain medicine, sometimes we just wait and let them try and pass it.

What does surgery involve?

There are three types of surgery.

There's shock wave lithotripsy -- it's a noninvasive procedure where you basically put shock waves onto the stone externally to break up the stone. That's a good treatment if it works. It requires not as much anesthesia.

The other that we use most commonly probably here is ureteroscopy: taking a little telescope without any incision, you just go up where you pee, go up to the stone, and you use (a) laser to break the stone into pieces.

The much more invasive way is called percutaneous nephrolithotomy, and that's when you go through the back. That's for very large stones.

The incisions are only about 1 cm, and you use telescopes and you basically get into the kidney, onto the stone, with one telescope through the back, and you treat the stone.

If someone has had this once, are they at more risk of having it again?

Definitely. If you have a stone, you do have a much higher risk of getting another stone within the next 5 to 10 years.

What are these stones made of?

About 95 percent of people have calcium stones. But there are other stones. There (are stones) associated with infection, there's stones associated with acid urine called uric acid stones. There's some medications actually cause stones.

Can stones ever be fatal?

They can. If you have a stone passing down and there's an infection behind it, and the urine can't get out, so the infection sits there, it festers and can be like an abscess and it can actually be fatal if you don't get treated.

Stones can also cause kidney issues. If you leave a stone in there that's blocking your kidney, and it's a chronic condition -- it's been in there for a long time -- usually you see loss of function in that kidney.

Some stones, believe it or not, are completely asymptomatic. People don't even know they have them. It can be a very large stone or a small stone, but they get a CAT scan for some other reason, and that's when we pick it up.

Are you seeing more of these cases?

With the increase in obesity, we know that that's one of our biggest risk factors, and it is increasing in the population. We're seeing more people developing stones. We're seeing more children developing stones. We think this is really largely due to diet.

We're seeing it in all populations. Before, males were highly predominant stone formers versus females. Now females are catching up. And kids had a very low rate of stone disease, and now we're seeing more kids with it. I think diet, the foods we eat, have really been playing a part in the increase we're seeing.