Cryptorchidism is a common congenital urogenital malformation in male children, mainly manifested as scrotal hypoplasia on the affected side and empty scrotum without testicles. It accounts for 9.2%~30% in immature children and 3.4%~5.8% in mature children. Cryptorchidism, in addition to causing deformity, psychological trauma, easy complication of torsion and injury, the biggest harm is to cause infertility and malignant changes. According to statistics, the infertility rate of bilateral cryptorchid testis is more than 90%, and unilateral is 50.6%, and the malignant rate of cryptorchid testis is 30~46 times of that of normal testis, which may be related to the local temperature of testis, obstacle of blood transportation, endocrine dysfunction, and may also be related to the different degree of underdevelopment and atrophy of tubules and germ cells, especially the temperature, the abdominal cavity is higher than the scrotum by 2~4 ℃, and the excessively high temperature causes the testicular flexure to degenerate and atrophy and cause the malignant change. malignant changes. Therefore, timely diagnosis and reasonable treatment of this disease are crucial. Diagnosis Cryptorchidism can be diagnosed by physical examination, ultrasound and CT, but the following two special cases must be ruled out: one is that cold stimulation and nervousness can make the testicular muscle contract to cause the illusion of testicular descent. Secondly, testicular retraction must be excluded, which is quite important, because it is easy to misdiagnose testicular retraction as cryptorchidism, the former is due to the excessive contraction of testicular muscle, the testicle stays above the scrotum or in the inguinal canal for a certain period of time, and when physical examination is performed, the testicle can be entered into the scrotum by pushing it gently down with the hand and stayed there for a few moments. Generally no treatment is needed, and the testicles can descend into the scrotum by themselves and no longer retract when they reach puberty. Currently, most people believe that the chance of self-descending after 6 months is extremely small. Therefore, patients with cryptorchidism may still have the possibility of descending into the scrotum by themselves within 6 months, if the testicle has not descended after 6 months, hormone therapy should be started. When patients with cryptorchidism are not treated with medication, they should choose surgery decisively, preferably before the age of 2, because the cryptorchid tissue of the abnormally located testis will show obvious degenerative changes after the age of 2, and such changes are irreversible, in addition, the older the infertility rate after the age of 2, the higher the rate of infertility. Another advantage of surgery is that even if the surgery fails to significantly improve the spermatogenic function of the affected testis, it can reduce the occurrence of tumors and make it aesthetically pleasing, removing psychological barriers for the patient. For patients with cryptorchidism who are operated over 10 years of age, especially those with intra-abdominal type, biopsy should be performed if malignant lesions are suspected intraoperatively in order to choose a reasonable surgical method. Even if the testicle is fixed by testicular drainage, the patient should be closely observed after the operation, because the cryptorchid testicular drainage does not prevent malignant changes in the future. According to statistics, if children with cryptorchidism are treated timely and actively, the fertility rate of unilateral cryptorchidism can be increased to 75%, and bilateral cryptorchidism can reach 50%.