Urethral perfusion is mainly to dilute drugs and inject them into the urethra through the urethral orifice to achieve therapeutic effects, most commonly bladder tumor perfusion chemotherapy. It is also possible to leave a catheter through the urethral orifice and then inject the drug into the bladder through the catheter and carry out chemotherapy for bladder tumor by changing different positions, this way has a very good therapeutic effect on preventing bladder tumor recurrence. At present in many hospitals also treat prostatitis through urethral irrigation, this treatment option is not recommended, the effect is not good, it tends to increase the possibility of retrograde infection and also can lead to damage to the bladder, urethra and prostate mucosa.