Diagnosing Kidney Stones

Kidney Stone Institute

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Kidney Stone Institute

Diagnosing Kidney Stones

Most people are diagnosed with kidney stones after experiencing unforgettable pain. Find out about kidney stone symptoms. 

When to call your doctor

It's important to consult a doctor to determine if symptoms are caused by a stone or by another medical problem. Unfortunately, the severity of symptoms is not a good indicator of the stone's size, location or if it will pass on its own. Radiology tests are the only reliable way to view kidney stones.

Contact Kidney Stone Institute

A doctor's referral is not required to make an appointment.

1-888-326-3830 (toll-free)


Monday through Friday, 8 am to 4:30 pm
Outside of these hours, you can call us and speak with a registered nurse who will review your symptoms and make recommendations to help you get appropriate care.

When to go to the ER

Many people with kidney stones go to the emergency room (ER) with severe pain. In the ER at St. Joseph's, we specialize in treating patients with kidney stones. We focus on reducing pain, making an accurate diagnosis and pairing patients with urologists who specialize in treating kidney stones.

A visit to the emergency room should be considered if you have:

  • Fever and stone pain (may be a sign of a serious infection)
  • Pain that is not helped by home medications
  • Severe nausea or vomiting that prevents drinking fluids
  • Previous difficult stone episodes

Tests for locating stones

A CT scan of the abdomen and pelvis is the best way for your doctor to determine if you have a kidney stone. A CT scan is a specialized x-ray test that allows your doctor to look inside your body. It is usually done after a clinical examination by your doctor or a doctor in the emergency room.

On the CT scan, stones are easily recognized. They look similar to bones but are outside of the skeleton. Unfortunately, plain x-rays and ultrasounds tend to miss many stones.

The scan is quick and painless and can help determine:

  • If you have a kidney stone
  • The location, size and number of kidney stones
  • How much obstruction the stone is causing
  • The density of the kidney stone
  • The best treatment for your kidney stone

The CT scan also gives information about all abdominal organs, so it may help to determine causes of abdominal pain that aren't related to a kidney stone. These can include appendicitis, gall bladder disease, abdominal aneurysms, bowel disease and hernias.

Low-dose scans

During the past 15 years, computed tomography (CT) scanning has become an invaluable tool in detecting and characterizing renal and ureteral stones.

The use of CT gives physicians the precise number, size and location of kidney stones. Signs of obstruction or complications are also visible. Conventional CT does involve a higher radiation dose than methods such as x-ray or an intravenous pyelogram (IVP), but it gives much more accurate information.

Because kidney stones tend to recur prompting additional imaging, and many kidney stone patients are relatively young, we continue to work toward a goal of fewest scans and least radiation per scan.

Dr. Portis and his colleagues have developed a reduced-radiation-dose CT for specified patients with kidney stones. When compared to conventional CT scans, the average radiation dose for the reduced-radiation version is nearly 75 percent less.

Use of low-dose stone CTs have dramatically reduced the radiation dose to our patients while still giving us the precise information needed to help us manage their kidney stones. It's just another innovation that sets HealthEast Kidney Stone Institute apart.

Radiation dose (mSv):

  • Conventional CT – 15
  • Low-dose CT – 2.8
  • IVP – 3


We offer early follow-up to all patients discharged from our emergency room.

We strongly believe that all patients should be evaluated with a CT scan. A proper CT scan should provide the information needed to predict your chances of passing the stone. It is also used to determine the size and location of the stone (or whether a stone is even present). Until this basic information is known, it is difficult to make decisions about care. Unfortunately, symptoms are often misleading. Larger more problematic stones have a tendency to cause fewer problems than small stones.