1.What are the main clinical problems of nephrography and renal dynamic imaging? Nephrograms or renal dynamics can be used to understand the function of the kidneys and the degree of renal impairment, as well as to determine whether there is an obstruction in the urinary tract. GFR and ERPF are two important parameters for determining renal function. Zhao Yinlong, Department of Nuclear Medicine, Second Hospital of Jilin University 2. What are the differences between nuclear medicine methods and other methods of kidney function tests (such as blood creatinine and urea nitrogen measurement)? Both nephrogram and renal dynamic imaging use the principle of isotope tracer technique to observe the kidney and urinary tract. The tracer drug used is excreted from the urinary system and its passage through the kidneys and urinary tract reflects the process of urine production and excretion. The information obtained is more consistent with the condition of the urinary system in the physiological state, and the results are more accurate. In addition, some laboratory tests of renal function commonly used in clinical practice can only obtain the function of the sum of the two kidneys, and cannot understand the specific situation of each kidney. In contrast, nephrogram and renal dynamic imaging can observe and judge the respective function of each kidney and the condition of each side of the urinary tract, which is a very valuable advantage in clinical practice. 3.Which is better, nephrography or renal ambulatory imaging? Nephrogram is a non-graphic functional examination method, which is less expensive but has higher error and less accurate results. Renal dynamic imaging can get images of both kidneys and bilateral urinary tract, and the results obtained are informative, sensitive and accurate are significantly higher than nephrography, so nowadays, renal dynamic imaging is more often used in clinical practice. 4.What preparation is needed to perform renal dynamic imaging? No special preparation is needed before the examination. It should be noted that because renal dynamic imaging is a functional test, it should be performed under the normal physiological state of the human body, so the patient should not fast and should eat normally, otherwise it may cause errors in the results. 5.Can dialysis patients have nephrogram and renal dynamic imaging? Both nuclear medicine examinations are very safe and the drugs used have little effect on the kidneys. Therefore, patients with severely impaired kidney function can also undergo these examinations. 6.Can children have renal dynamic imaging? Since the imaging agent used for renal dynamic imaging is cleared from the body quickly and has a very short half-reduction period, it is very safe for human body, so children and even newborns can undergo renal dynamic imaging. Since the patient’s body has to be kept still during the examination, some sedative medication is needed before the examination for children who cannot cooperate. 7.Can I have dynamic renal imaging immediately after an intravenous pyelogram or enhanced CT examination? Intravenous pyelogram or enhanced CT examination requires the injection of contrast agent, which has a transient effect on the kidney function. If you perform renal dynamic imaging immediately after these tests, it may cause errors in the results of renal dynamic imaging, so renal dynamic imaging should not be performed on the same day as these tests.