1.Recurrent urinary retention (unable to urinate at least once after extubation or 2 times of urinary retention). 2.Patients with long-term urinary tract obstruction symptoms (nocturia more than 3 times) whose symptoms are not improved by conservative treatment. 3.Patients with prostatic hyperplasia who have repeated hematuria and whose conservative treatment is ineffective. 4.The remaining urine exceeds 50ml and gradually increases. 5.Middle lobe enlargement of prostate with bladder spasm. 6.Prostate enlargement with bladder stone, diverticulum, tumor, recurrent urinary tract infection. 7, prostatic hyperplasia causing hydronephrosis.