The kidney is wrapped by the peritoneum while the kidney tip is loose and can move in the abdominal range, some even descend into the lower abdomen or pelvis, or cross the midline to the opposite side of the abdomen, this kind of kidney prolapse is called wandering kidney, usually seen in the right side. The main symptom is low back pain, which can lead to hydronephrosis or upper urinary tract infection due to ureteral bending. It is often complicated by renal hypoplasia, renal malrotation, renal vascular malformation and ureteral overgrowth and other abnormalities. Common tests: i. CT CT examination of the kidney is a method to examine the kidney by CT. The purpose is to check kidney diseases, such as stones, inflammation, tumors, etc. It is suitable for the examination of patients with kidney diseases. Precautions: 1. The qualitative diagnosis of renal parenchymal masses is often difficult and must be combined with clinical manifestations, urography, ultrasound and other examinations for comprehensive analysis to improve the correctness of diagnosis. 2. For certain high-density cysts in the kidney, CT diagnosis has some difficulties. CT index interpretation results: Normal: No abnormality in the kidney. Abnormal: 1.It can identify the location, size, morphology and invasion range of the mass; it can identify the mass as cystic, substantial, fatty or calcified lesion, and even make qualitative diagnosis. 2.When intravenous urography shows a dysfunctional kidney, CT can identify the site, nature or congenital developmental abnormality of the lesion. 3.It can detect fine calcifications, stones or negative stones that cannot be visualized by ordinary X-ray examination. 4.It has greater value in the diagnosis of renal tuberculosis and can show intrarenal destruction, calcification of pathogenic origin and perinephric abscess. 5.It can determine the site and extent of kidney damage and perirenal hematoma, as well as postoperative complications. Second, radionuclide kidney scan Applying the kidney to selectively concentrate and excrete radionuclide labeled compounds through the scanner in vitro to visualize the kidney. Based on the images obtained, the location, morphology, size and density of radioactive distribution of the two kidneys are analyzed for comparison, and the diagnosis is made by combining with the clinical condition. When renal artery stenosis causes renal atrophy, the kidney scan shows that the affected kidney is smaller than normal and the distribution of radioactivity is sparse and uneven. The contralateral kidney may show compensatory hypertrophy. If renal artery stenosis has not yet caused changes in renal function, the renal scan may show no significant abnormal changes. Precautions: Unsuitable population: generally no unsuitable population. Pre-test contraindications: Maintain a regular routine and diet to help the examination proceed smoothly. Requirements for examination: No special preparation is required for this examination. The patient is generally placed in a prone position with the waist straight and the spine aligned with the midline of the probe so that both kidneys are in the effective field of view of the probe. After intravenous injection of the scanning agent, the kidney is scanned with the scanner in vitro for a certain period of time, and the kidney is directly printed out or photographed with a scintillation camera. The anatomical landmarks of the spine, iliac diverticulum, and rim are made on the scan map. The normal kidney is located on both sides of the lumbar spine, with the upper pole of both kidneys close together and the lower pole farther apart. The long axis of the two kidneys is in the shape of “eight”, and the upper pole of the kidney is generally level with the 12th thoracic vertebra and the lower pole with the 3rd lumbar vertebra. The normal kidney scan shows an oval shape with clear outline and neat edges, except for the sparse distribution in the hilar region, the rest are evenly distributed.