According to the technical scheme, the
catheter capable of achieving the constant
bladder capacity is characterized in that the
catheter comprises a
catheter body, the catheter body comprises an inner pipeline, an outer pipeline and an
insertion body, the head ends and the
tail ends of the inner pipeline and the outer pipeline are closed to form an interlayer cavity, a through hole is communicated with the inner pipeline, a small
balloon is arranged on the outer pipeline, and the small
balloon is communicated with the
insertion body. The outer pipeline is provided with a first injection
pipe, the first injection
pipe is communicated with the small
balloon through the interlayer cavity, the guide
pipe body is provided with a large balloon, the outer pipeline is provided with a second injection pipe, and the second injection pipe is communicated with the large balloon through a connecting pipe; the small balloon and the large balloon are arranged on the catheter body, after the catheter body is placed into the bladder, a certain amount of liquid needs to be injected into the small balloon before radiotherapy to achieve the effect of fixing the catheter body, and a certain amount of air or normal
saline is injected into the large balloon during radiotherapy every time, so that the constant
bladder capacity is achieved; therefore, the radiotherapy accuracy is improved, and the
radiotherapy treatment effect is improved.