Significance of testicular biopsy: To differentiate obstructive azoospermia from non-obstructive azoospermia (loss of spermatogenic capacity due to testicular disorders).
Main indications
1, azoospermia with normal testicular size.
2, oligospermia with moderately reduced testicular volume.
3.Low spermatozoa or azoospermia with small or asymmetrical testes such as testes of unequal size, one side of the vas deferens cannot be retrieved or epididymal sclerosis, etc. It should be proved whether spermatozoa occur in both testes, as there may be obstruction on one side and testicular dysfunction on the other.
4.If the lesions of both testes are basically the same, in order to determine the degree or type of testicular damage, the healthier side of the testis is often selected for biopsy
5. In obstructive azoospermia, bilateral testicular biopsies should be performed to determine which side is suitable for microsurgical anastomosis.
6. Biopsy of cryptorchidism can detect whether there is in situ cancer. Testicular biopsy of unexplained testicular masses can clarify the diagnosis.
7. Testicular biopsy can also be performed to evaluate the long-term effects of male sterilization or the effects of environmental factors, cytotoxic drugs and radiation on the spermatogenic function of the testis.
The purpose of testicular biopsy is to achieve
1, clinical examination of testicular volume and hormone level determination of normal infertility patients.
2, Semen examination for oligospermia, follicle stimulating hormone is within normal range, spermatogenic function can be determined by biopsy.
3.For oligospermia due to varicocele, biopsy can assist in the diagnosis of the degree of influence of varicocele on the spermatogenic function of the testis.
4.When cryptorchidism is fixed during puberty or late development, preoperative biopsy can evaluate the spermatogenic function and exclude the possibility of malignant change.
5. Combining testicular biopsy with endocrine examination can determine whether the testicular hypofunction is primary or secondary.
6.Vasography shows obstruction of the vas deferens, and biopsy can help diagnose the spermatogenic function of the testis and select vasectomy.
7.Evaluation of efficacy before and after hormonal drug treatment.
8.Biopsy can assist in the early diagnosis of germ cell tumors.
Methods of testicular biopsy
1.Excisional method biopsy
After disinfection of the scrotal skin, local anesthesia is applied, the testicle is fixed by hand, the scrotal skin on the surface is tensed, and an incision of about 1 to 2 cm is made in the area with few blood vessels. The white membrane of the testis is incised in the shape of “∧”, about 0.5cm long, and the testis is gently squeezed to expose the testicular parenchyma, and a tiny bit of testicular tissue is taken as a specimen and sent to pathology for pathological tissue examination. The procedure is strictly disinfected and carefully operated, and usually does not cause infection, hematoma or pain. In a few patients, the sperm count decreases within a short period of time after the testicular tissue is removed, and it takes about 4 months to recover gradually.
The skin and testes are cut open and the varicocele in the testes are removed. This is a very complete procedure, which can accurately reflect the spermatogenic function of the testes without any errors in the examination and the results are reliable. However, this test is very traumatic and requires incision of the skin and the white membrane of the testes, which requires suturing and stitching after surgery, causing more pain and inconvenience to the patient. Although this test method is accurate, it is not easy to carry out clinically because of the pain and the patient’s fear of surgery, etc.
2.Puncture method
With the needle and needle for puncture, after routine disinfection of the skin and anesthesia, the puncture needle is punctured into the testis through the scrotal skin, the core is withdrawn, the needle is suctioned to obtain a little testicular tissue, and then the puncture needle is withdrawn, and if the tissue is too little at one time, it can be suctioned several times from different parts, and after the end, the puncture site is bandaged and the testicular tissue is sent for examination.
This method has less damage and pain compared with the incision method and does not require suturing. Its shortcoming is that the needle aspiration cytology examination can only obtain a few tissue cells and cannot see the overall structure of the tissue, so it cannot accurately reflect the spermatogenic function of the testis, and there are false positive and false negative errors, and the results of the examination are unreliable and easily misdiagnosed.