A kidney ultrasound, also known as a renal ultrasound, is a non-invasive imaging technique that uses sound waves to create pictures of the kidneys and surrounding structures. It allows healthcare providers to visualize the size, shape, and position of the kidneys. Unlike X-rays or CT scans, an ultrasound does not use radiation, making it a safe option. The sound waves travel through the body, and their echoes are converted into real-time images on a screen, providing a detailed view of the renal system.
Preparing for the Procedure
Preparation for a kidney ultrasound can vary slightly depending on the specific reason for the examination, but it is generally minimal. Patients are often able to eat and drink as usual before the test. However, in some instances, especially if the bladder needs to be assessed or if a more detailed look at the renal arteries is required, specific instructions will be provided. This might involve fasting for several hours or drinking a specific amount of water, typically 24 to 40 ounces, about an hour before the appointment to ensure a full bladder.
It is helpful to wear comfortable, loose-fitting clothing to the appointment, as you may be asked to change into a medical gown. Any jewelry or metal items in the area being examined should be removed, as they can interfere with the imaging process. If you are taking any medications, it is advisable to discuss them with your doctor beforehand, though typically most medications can be continued as usual.
The Ultrasound Process
Upon entering the examination room, you will typically be asked to remove your clothing and any jewelry, changing into a hospital gown. You will then lie on a padded exam table, most commonly on your back, though the technologist may ask you to shift positions, such as turning to your side or even sitting up, to get clearer views of the kidneys. A warm, water-soluble gel will be applied to your skin over the area where your kidneys are located, usually the abdomen and lower back. This gel is important as it helps to eliminate air pockets, allowing the sound waves to travel smoothly from the transducer into your body.
The ultrasound technologist, also known as a sonographer, will then use a small, hand-held device called a transducer, or wand, pressing it gently against your skin and moving it around the gel-covered area. This transducer sends and receives high-frequency sound waves, which a computer converts into real-time images displayed on a monitor. The procedure typically lasts between 20 to 30 minutes, during which the technologist may ask you to hold your breath briefly or change your body position to capture specific images.
What to Expect Afterward
Once the kidney ultrasound is complete, the technologist will wipe the gel from your skin. You can then get dressed and resume your normal daily activities immediately, as there are typically no restrictions after the procedure.
The images captured during your ultrasound will be reviewed and interpreted by a radiologist, a medical doctor specializing in interpreting medical images. The radiologist will prepare a detailed report of their findings, which is then sent to the doctor who ordered your ultrasound. While the ultrasound technologist cannot discuss the results with you directly at the time of the exam, your referring doctor will typically receive the report within 24 to 48 hours. Your doctor will then contact you to discuss the findings and determine any next steps, which might include further tests or a treatment plan.