Epididymal stones are also known medically as seminal vesicle stones, and stones that occur within the seminal vesicles are called seminal vesicle stones. It is extremely rare clinically. Due to chronic inflammation of the seminal vesicles, ejaculatory duct obstruction, seminal vesicle fluid retention, metabolic disorders, etc. caused by inorganic salt crystals deposited on the shedding of epithelial cells and inflammatory exudate formation. Stones are often multiple, generally small, 1-2 millimeters in size, the surface is smooth and hard brown. Seminal vesicle stones can occur singly or in multiples, and rarely show symptoms, occasionally see blood sperm, ejaculation pain or perineal discomfort. Seminal vesicle stones are rare, and the stones are round, hard and smooth. Epididymal stones prevention methods: 1, for asymptomatic seminal vesicle stones, can not be treated; such as symptoms or obstruction aggravation, symptomatic treatment and anti-infection treatment. Currently there is no evidence that the treatment of lithotripsy is effective. 2, seminal vesicle stones combined with prostatic hyperplasia, the diameter of 1.2mm or less, after prostatectomy to lift the ejaculatory duct obstruction factors, there is a possibility of self-discharge. If the internal medicine treatment is ineffective and the symptoms are severe and the person has already given birth, the only effective treatment is to remove the seminal vesicles together with the stones. 3.For those who have not had children, and whose seminal vesicle stones have caused partial vasovaginal obstruction, as their testicular spermatogenesis is still normal, depending on the degree of inflammation, especially at the early stage of infection, the quality of semen can be improved through the application of antibiotics or with a small amount of prednisone treatment to make the inflammation subside. 4, the vas deferens obstruction is more serious, can use urethroscopic longitudinal incision of the posterior urethra or spermatophorectomy, the operation to see the vas deferens injection of indigo rouge in the surgical field, proving that the operation has been effective and thorough, after the operation, 45% ~ 60% of patients with sperm quality improvement, pregnancy rate of 29% ~ 35%, but the operation should pay attention to avoid damage to the rectum and the urethra. 5.Spermatozoa stones cause obstruction of the vas deferens, which is a serious cause of infertility, artificial insemination can be used. Some people also use the spermatophore made of silicone to plant under the skin, connect it to the epididymal duct, and then puncture the semen in the spermatophore for artificial insemination. Successful pregnancies have been reported, and the technique is constantly being improved.