Digital Subtraction Angiography (DSA) is a very advanced large advanced precision medical imaging device that is completed by applying a computer program for two imaging sessions. Before injecting the contrast medium, the first imaging is performed and a computer is used to convert the image into a digital signal for storage. After the contrast agent is injected, the image is imaged again and converted into a digital signal. The two digital times are subtracted and the same signal is eliminated to obtain a contrast-only image. However, because the price and maintenance cost of this equipment is very expensive, only large hospitals have it, and it is generally used clinically for interventional procedures for cardiovascular and cerebrovascular diseases or tumors. Our hospital has a large DSA (US$670,000) from GE, and we are the first in the province to carry out tubal imaging and interventional treatment of tubal obstruction with DSA, which shows the incomparable superiority of tubal imaging or interventional treatment by ordinary X-ray machines or digital X-ray machines. 1.With the digital subtraction function, continuous and complete dynamic images of the whole tubal peristalsis can be obtained. 2.Since the images of bones and soft tissues are subtracted, the images of uterus and fallopian tubes can be displayed in high definition, which improves the accuracy of diagnosis and can record the treatment process completely. 3. Due to the design features of DSA machine, the amount of radiation can be reduced by about 70% compared with ordinary X-ray machines, and the radiation dose received by patients during the operation is smaller. 4.Due to the use of subtraction function, the intraoperative contrast agent used is diluted twice with saline to reduce its concentration by twice, avoiding the damage to the uterus, fallopian tubes and pelvic cavity caused by high concentration and high permeability contrast agent, and at the same time, high definition images can be obtained. 5.The application of high-pressure syringe in the procedure replaces the traditional hand-pushed contrast imaging. The flow rate, total volume and pressure of the injected contrast agent can be pre-set, and the optimal injection pressure can be automatically adjusted through computer-controlled execution, which obviously reduces the patient’s pain during the imaging process and avoids damage to the uterus and fallopian tube mucosa due to excessive pushing pressure, improving the accuracy of diagnosis and treatment. The success rate of uterine and tubal intubation can be significantly improved by using DSA pathogram technology. A clear surgical pathogram can be easily obtained by injecting a small amount of contrast into the uterine cavity, which can precisely determine the location of the uterine angle and the obstructed end of the fallopian tube, and improve the success rate of intubation and the rate of tubal recanalization. It avoids the damage to the uterine mucosa and fallopian tubes caused by blind operation and reduces the complication rate. It greatly shortens the operation time and reduces the X-ray radiation dose to patients and doctors. 7. Operate under asepsis in the interventional operating room to avoid uterine and pelvic infections caused by the operation.