A renal scan involves the use of nuclear radioactive material to examine your kidneys and assess their function. A renal scan is also known as a renal scintigraphy, nuclear renal imaging, or a renogram.

Other forms of renal imaging include CT scans, X-rays, ultrasounds, and MRIs. Read on to learn how and why nuclear renal scans are performed and what they can reveal.

在此过程中，一名技术人员向您的静脉注入了一种称为放射性同位素的放射性材料。放射性同位素释放伽马射线。伽马摄像头或扫描仪可以从体内检测到伽马射线。

The gamma camera scans the kidney area. It tracks the radioisotope and measures how the kidneys process it. The camera also works with a computer to create images.

These images detail the structure and functioning of the kidneys based on how they interact with the radioisotope.

Images from a renal scan can show both structural and functional abnormalities. This helps doctors diagnose a kidney problem in its earlier stages without invasive techniques or surgery.

肾脏功能肾扫描识别问题ion. Normally, the two kidneys:

  • remove尿素, or liquid waste, from the blood by producing urine
  • maintain a balance of chemicals, such assodium和钾, in the blood
  • 提供激素红细胞生成素, which supports red blood cell growth
  • 控制blood pressureby producing the hormone renin
  • provide the hormone calcitriol, which suppliescalciumto bones

A change in renal function typically begins gradually and without symptoms. In many cases, routine blood and urine tests, such as what’s done on an annual physical, show the first signs ofreduced kidney function.

A renal scan can identify the cause of reduced kidney function. The cause may be a disease, obstruction, or injury to the kidneys.

A renal scan can explore more than one type of problem during the same procedure. A renal scan measures kidney function by monitoring the flow of the radioisotope and how efficiently your kidneys absorb and pass it.

It also shows abnormalities in the structure, size, or shape of your kidneys.

Renal scans can identify and evaluate:

Typically, you don’t need to make any special preparations before a renal scan. You can usually eat your normal diet. Sedation isn’t usually necessary.

You should tell your doctor about any prescription or over-the-counter medications you’re taking. Discuss how to use them before and during the test.

Your doctor may provide special instructions if you’re taking medications that could affect the results of the renal scan. These medications include:

A renal scan is an outpatient, or same-day, procedure. You won’t have to stay at the hospital overnight. A nuclear medicine technician performs the scan. This is usually done in either in a hospital radiology department or a medical office with special equipment.

Depending on the reasons for your scan, testing may take between 45 minutes and 3 hours. Talk to the technician beforehand if you’re claustrophobic because the camera may pass close to your body.

Before your procedure, you’ll remove any of the following that could interfere with your scan:

  • clothing
  • 珠宝
  • dentures
  • metal items

You may have to change into a hospital gown. You’ll then lie down on a scanning table.

技术人员可以将静脉内（IV）线插入您的手或手臂的静脉中。然后，技术人员将将放射性同位素插入手臂的静脉中。您可能会在注射中快速，尖锐的戳戳。

There may be a waiting period between the injection and the first scan to allow your kidneys to process the radioisotope.

The scanner will detect the gamma rays from the radioisotope and create images of the area. Because any movement can alter or blur the image, you’ll need to stay still as the scanner creates an image.

If you need the scan because you have high blood pressure, you may receive a high blood pressure medication called anangiotensin converting enzyme(ACE) inhibitor during testing. This allows for comparison of your kidneys before and after the medication is absorbed.

If you’re having the scan to look for kidney blockages, you may receive a diuretic, or water pill, to promote the passage of urine through the kidneys. This allows your doctor to observe restrictions to urine flow.

If you need to have an empty bladder for the scan, you may need a soft tube called a catheter to maintain this condition.

The technician will remove the IV line and catheter after the scan. You can then change back into your clothing and leave the hospital.

You can usually return to your regular diet and daily routine after your procedure unless your doctor advises you otherwise. The radioisotope will exit your body naturally. Frequently drinking fluids and urinating can hasten this process.

Nuclear medicine imaging is considered safe. The radioisotope exposes you to less radiation than an X-ray. The small amount of radiation exposure is primarily in the kidney area. It passes from your body naturally within 24 hours.

The low doses of radiation used in nuclear medicine procedures don’t have a connection to any long-term negative effects.

Even though the radiation exposure is minimal and short-term, tell your doctor if you’re pregnant or think you might be pregnant. Also, tell your doctor if you’re breastfeeding to ensure that there’s no contamination of your breast milk.

Unlike intravenous dyes, radioisotopes carry few risks of allergic reactions. Allergic reactions to radioisotopes are possible but rare. A renal scan is a good option if you’ve had a reaction to the contrast dye used in X-rays of the urinary system.

IV的针刺可能会导致：

  • discomfort
  • redness
  • bleeding
  • swelling

如果这些症状持续存在，请与您的医生联系。他们可以表明感染。

根据您的身体状况，或者是最近手术还是受伤，您可能会感到不适或躺在扫描仪桌子上的痛苦很长一段时间。

You may also feel dizzy when you get up from the table. This dizziness and discomfort should only last a moment.

After the technician completes your renal scan, a nuclear medicine radiologist will interpret the image findings. They’ll send a comprehensive report to your doctor. Your doctor will discuss the results with you.

Abnormal results of a renal scan can indicate:

您的医生可能需要进一步测试以澄清诊断。您的肾脏大小和形状会影响扫描结果。异常的肾脏结构可能导致不正确的读数。可能需要进一步确认。

Also, because renal scans can’t identify the difference between a cyst and a tumor, additional diagnostic procedures may be necessary for a more definite diagnosis.