1. Detect the post-void residual of the bladder before and after surgery, compare the impact of surgery on the bladder, and determine whether to carry out corresponding rehabilitation training.

2. The post-void residual value of the bladder is one of the surgical indications of the warlock related to prostatic hyperplasia.

3. According to the symptoms of patients, we can measure the bladder volume on the bladder scanner to screen for acute and chronic urinary retention.

4. Provide bladder volume data before inspection and post-void residual data after inspection for Urodynamics.

5. The post-void residual data is used as one of the criteria for whether patients can be extubed or discharged after surgery.

6. The post-void residual data was used to verify the preoperative rehabilitation effect and postoperative recovery effect of stress urinary incontinence.

7.  Provide bladder volume data for patients with dysuria before inserting catheter to determine whether it is necessary to perform urinary catheterization, avoid unnecessary catheterization, and reduce the incidence of urinary system infection.