Varicocele usually refers to the abnormal elongation, dilation and tortuosity of the trabecular plexus of the spermatic veins. It is a common and frequent disease among young and middle-aged men, and its incidence accounts for about 10%-15% of the male population. It can be divided into two main categories according to its etiology: 1. primary varicocele: due to anatomical factors and dysplasia; 2. secondary varicocele: due to intra-abdominal or retroperitoneal occupying lesions such as tumors and ectopic vessels that compress the superior spermatic veins. The primary spermatic varicose veins are the most common clinically. There is also the concept of subclinical varicocele, which refers to minor varicocele that cannot be detected on physical examination but can be detected by color Doppler ultrasound and other examinations. It is generally considered to be diagnosed when the diameter of the intra-seminomatous vein exceeds 2 mm. Its prevalence increases with age in adolescents after puberty and may be related to the increase in height, weight, testicular volume and blood supply. It is now recognized that palpable varicocele can affect fertility and is a major benign condition causing male infertility. In the literature, 80% of men with secondary infertility and 40% of men with primary infertility clinically suffer from varicocele, and studies have now shown that male infertility is associated with a complex series of pathophysiological and immunological changes in the spermatic veins, testes, and epididymis secondary to varicocele. Clinically, it can be asymptomatic, or scrotal swelling, vague pain and discomfort radiating to the ipsilateral groin area and small abdomen, aggravated after standing and physical activity, and relieved after lying down at rest; and most patients are detected during routine physical examination or when they visit the hospital with complaints of infertility. Shen Heqing, Department of Urology, Xiangcheng People’s Hospital, Suzhou, China Varicocele is the main cause of infertility in fertile men, and can also cause complications such as scrotal pain on the affected side, testicular atrophy, and decreased spermatogenesis. What exactly is the cause of primary varicocele? Because varicocele occurs on the left side in 90% of cases, the main anatomical causes are as follows: 1. The left internal spermatic vein has more abnormal valve function and absence than the right; 2. The left renal vein may be squeezed by the mesenteric artery and aorta and affect the reflux of the internal spermatic vein, forming the so-called proximal clamp phenomenon; 5. The right common iliac artery may compress the left common iliac vein and affect the reflux of the left vas deferens vein, forming the so-called distal clamp phenomenon; 6. Human walking upright makes the blood in the spermatic vein more prone to top-down reflux due to gravity; however, in recent years, it has been found that varicocele patients with bilateral simultaneous onset can be more than 8%-40%, and by After traditional open surgery or laparoscopic high ligation of the internal spermatic vein, some patients still have recurrence and persistent testicular function loss within a short period of time. Therefore, the anatomical characteristics of the left internal spermatic vein cannot fully explain its pathogenesis and clinical features. Recent studies have suggested that the etiology of varicocele may include: 1. poorly developed connective tissue in and around the vein wall and levator muscle, which weakens the support and pumping effect around the internal spermatic vein; 2. loss of tension in the external spermatic vein secondary to varicocele in the internal spermatic vein. The study confirmed that high ligation of mild varicocele (Ⅰ°II°) can achieve satisfactory results, and microscopic ligation under the external ring in patients with varicocele above Ⅲ° has better results than other procedures, suggesting that severe varicocele may not be caused by simple reflux. The pathophysiological and immunological changes of the spermatic veins, testes and epididymis after varicocele are as follows; 1. The pathology of the internal spermatic veins reveals degeneration of the vascular endothelium, hyperplasia of the intima, hypertrophy of the mesothelium and smooth muscle of the valves, and severe mechanization of the valves, thus causing blood stasis. The pathology of testicular injury showed detachment of spermatogenic cells, interstitial edema, and small interstitial vascular lesions. Epididymal lesions manifest as interstitial edema, epithelial cell degeneration, and disorderly arrangement of brush border on the surface of tubular epithelial cells.2. Recent studies have shown that varicocele infertility is related to immune factors. The presence of anti-sperm antibodies (ASA) in peripheral blood and semen of patients with varicocele infertility was found among others. Anti-sperm antibodies enter the testes and epididymis and can interfere with the process of sperm production and maturation, leading to a decrease in the number of sperm or adhesion to the sperm membrane, causing morphological and functional abnormalities of sperm. The exact correlation between varicocele and male infertility exists, but its specific pathological mechanism has not been fully elucidated. The left spermatic vein refluxes the blood from the left renal vein, bringing the steroids, catecholamines and 5-hydroxytryptamines secreted by the adrenal glands and kidneys to the testes, which can cause vasoconstriction and premature sperm shedding. 4. varicocele on the left side can affect the right testicular function, because there are abundant venous traffic branches between the testes bilaterally. Spermatogenesis in the right testicle. If varicocele does not receive timely clinical intervention, the damage to testicular function will increase slowly and eventually cause irreversible functional damage to the testes, leading to infertility. In contrast, treatment of young patients, even if they do not have fertility requirements, can effectively prevent infertility and androgen deficiency in adulthood. Therefore, it is necessary and beneficial to choose aggressive surgical treatment for varicocele, regardless of the age of onset, the degree of discomfort and varicocele, whether it is combined with decreased semen quality and testicular atrophy, or whether it is combined with male infertility. Clinically, not all patients require immediate surgery after the diagnosis of varicocele is confirmed. Except for those with obvious symptoms of discomfort in the scrotum, combined with testicular atrophy and decreased semen quality, mildly asymptomatic patients and those with mild symptoms and no concurrent infertility or no fertility requirements can also be temporarily treated conservatively. Sometimes we also need to take into account the patient’s own situation and condition. The current guidelines of the Chinese Society of Urology suggest that mildly asymptomatic patients do not need treatment; those with mild symptoms and no complications of infertility can be treated by holding up the scrotum, applying local cold compresses and reducing sexual stimulation; those with obvious clinical symptoms, which have caused testicular atrophy and decreased semen quality resulting in infertility should be actively treated surgically.