1.Overview
Cryptorchidism, also known as undescended testis or incomplete testicular descent, refers to the failure of the testis to descend from the lumbar retroperitoneum to the scrotum according to the normal developmental process. Cryptorchidism includes true cryptorchidism and testicular ectopic (i.e., abnormal descent). In true cryptorchidism, the testis is located in the normal pathway of descent and is often accompanied by an unclosed peritoneal sheath; in ectopic testis, the testis has completed its descent in the inguinal canal but fails to descend to the scrotum and is located subcutaneously, most commonly in the deep subcutaneous fascia outside the external inguinal ring.
The English word cryptorchidism is derived from the Greek words “kryptos” and “orchis”, meaning “hidden” and “testicle”, respectively. “testicle” respectively. If left untreated, cryptorchidism increases the chance of infertility and testicular cancer by 4 to 5 times compared to normal. Most men with bilateral cryptorchidism are infertile.
2.Diagnosis
2.1 Etiology
The etiology of cryptorchidism is not fully understood. At present, it is believed that the etiology of cryptorchidism is related to multiple factors such as endocrine, genetic and physical-mechanical factors.
2.1.1. Endocrine disorders and genetic factors Hypothalamic N-pituitary a testicular axis imbalance, abnormal testicular differentiation, androgen, anti-Mailer tube hormone, INSL3 deficiency or insensitivity can cause cryptorchidism. Familial cryptorchidism has also been reported. Abnormalities of autosomes and sex chromosomes can cause the occurrence of cryptorchidism.
2.1.2. Physical and mechanical factors affecting testicular descent
(1) The traction of the testicular lead: The proximal end of the lead is attached to the testis and epididymis, and its end is in the shape of a band. Since the scrotum is formed by the outward projection of the lower abdominal wall, the main end of the lead band is mainly attached to the bottom of the scrotum; another part of the lead band is attached to the pubic nodes, perineum or medial femur for its corresponding branches. It occupies a certain space between the groin and the scrotum. In the seventh month of embryonic life, the development of the testis causes significant morphological changes in the surrounding tissues, and in addition to the swelling of the introitus, the spermatic ducts also lengthen and thicken in a varicocele-like manner.
Afterwards, the swollen introitus begins to degenerate and contract, and the testis follows the dilated inguinal canal of the introitus, through the internal ring and out of the external ring. In most cases, the testis exits the external ring and follows the scrotal branch at the end of the band and enters the base of the scrotum. If the testis descends and stays in the internal ring of the inguinal canal and the external ring of the inguinal canal, incomplete descent can occur to varying degrees. If the testis does not descend to the bottom of the scrotum, but descends to the pubic region, perineum or femur along other branches at the end of the testicular lead, it becomes an ectopic testis.
(2) Intra-abdominal pressure contributes to the descent of the testis into the scrotum: This view suggests that increased intra-abdominal pressure is the original driving force that causes the testis to leave the abdomen and enter the inguinal canal.
(3) Anatomical obstruction: The testis needs to descend into the scrotum after the sphincter has fully descended into the base of the scrotum. Cryptorchidism complicated by unclosed sphincter and sphincter terminating at the pubic symphysis or above the scrotum is quite common, suggesting that abnormal attachment of sphincter may impede the descent of the testis; in addition, abnormal remnants of the introitus or fascia covering the scrotal population can prevent the descent of the testis.
2.2 Clinical manifestations and classification
Cryptorchidism can occur unilaterally or bilaterally, with unilateral being more common. In unilateral cryptorchidism, the incidence of the right side is slightly higher than that of the left side. Most children with cryptorchidism generally have no conscious symptoms, except for older children who occasionally complain of transient swelling and pain or complications. The main clinical manifestations are poor scrotal development on the affected side, empty scrotum, and no testicles can be found. Sometimes, the testicles can be found in the inguinal region or in the perineum outside the scrotum, which are generally smaller than normal and can be locally elevated.
There are various ways to classify the location and nature of cryptorchidism according to the cause of its development. There are two types of cryptorchidism: palpable testis and non-palpable testis, according to whether the testis can be reached by hand during physical examination. The more practical clinical classification methods are.
1. Retractable testis means that the testicular levator muscle is too active and the testis can retract to a position above the scrotum, but the testis can be placed in the scrotum by hand at night rest and during examination. This kind of patient does not need treatment, and the testicular position and size are normal after puberty, and the fertility is the same as normal people.
2.True cryptorchidism: high intra-abdominal cryptorchidism; inguinal cryptorchidism; high scrotal cryptorchidism; sliding cryptorchidism.
3.Ectopic testis means the testis is located outside the scrotum, such as above the pubic bone, the femur of the thigh, the perineum, the root of the penis and the transverse ectopic position.
4.Testicular anomalies (unilateral and bilateral metatesticular anomalies).
2.3 Examination test
2.3.1 B-type ultrasonography is the common localization examination method for cryptorchidism that cannot be felt clinically at present.
2.3.2 Chorionic gonadotropin (HCG) stimulation test is used for the differential diagnosis of cryptorchid testis, high intra-abdominal testis or testicular agenesis, which is often not felt in clinical examination. The method is to inject HCG l 500 IU once every other day for a total of 3 times, and check the serum testosterone level before and after the injection. If the serum testosterone level increases after the injection, it indicates the presence of functional testicular tissue.
2.3.3 Laparoscopy has been widely used for intra-abdominal cryptorchidism diagnosis and treatment. Cryptorchidism that cannot be palpated can be found clinically with laparoscopy in three ways: the spermatic vessels and blind end of the vas deferens are seen above the internal inguinal ring, lacking the testis; the normal spermatic cord enters the internal ring of the inguinal canal; and the intra-abdominal testis.
2.3.4 CT and MRl have also been used for the localization and diagnosis of intra-abdominal cryptorchidism in recent years, and both have a fairly high accuracy.
2.4 Diagnostic criteria
The diagnosis is not difficult and can be confirmed basically based on clinical manifestations and physical examination.
2.5 Complicating deformities
Cryptorchidism is often accompanied by unclosed sphincter on the affected side, which can be manifested as syringomyelia or inguinal hernia. It is not uncommon for intestinal hernia to become embedded and easily cause intestinal necrosis; it can also compress the spermatic cord blood vessels and cause further atrophy of cryptorchidism, leading to testicular infarction in serious cases. The common complications and associated deformities of cryptorchidism are as follows.
2.5.1 Decreased fertility or sterility The temperature of the scrotum is slightly lower than the body temperature, which is suitable for the development of germ cells in the normal testis. The testis is in the abdominal cavity or groin, where the temperature is the same as the body temperature, which is not suitable for the development of germ cells, and thus the testicular tissue structure is also poorly developed. Patients with bilateral cryptorchidism often lead to metachronous spermatozoa if left untreated, making most patients infertile. If the testis on one side is normal, the other side is normal and can maintain normal or near normal physiological function. If unilateral cryptorchidism is not treated, more than 30% of patients are infertile.
2.5.2 Testicular injury The testicles in the inguinal canal or near the pubic nodes are relatively superficial and fixed, and are easily damaged by direct external force.
2.5.3 Cryptorchid testicular torsion The chance of torsion of the undescended testis is more than 20 times higher than that of the testis in the scrotum. In right intra-abdominal cryptorchidism torsion, the symptoms should be differentiated from the signs rather like acute appendicitis, and cryptorchidism torsion can be excluded if there is a normal testicle in the scrotum.
2.5.4 Cryptorchid malignancy The chance of cryptorchid malignancy becoming testicular tumor is more than l0 times higher than that of normal testis. The age of onset of cryptorchid malignancy is mostly after 30 years old, and the rate of malignancy after testicular fixation before 2 years old is much lower than that of surgery at older age.
2.5.5 Cryptorchidism with associated abnormalities Cryptorchidism can be a single disease, but it can also be associated with other genitourinary system abnormalities and other endocrine diseases and genetic diseases. The most common abnormalities are vas deferens and epiglottis.
2.5.6 Abnormal testicular position often causes low self-esteem in older children.
3.Treatment
Cryptorchidism should be treated as soon as possible after the diagnosis is clear, so that the testicles in abnormal position can be lowered to the normal scrotal position. Because of its special structure, the scrotum has good heat dissipation and the temperature is generally lower than the abdominal temperature by about 2°C. It is the most ideal site for testicular development. In addition to increasing the spermatogenic capacity, the descent of the testes to the scrotum can also relieve the children and parents of psychological stress and early detection of malignant testes.
If the testicle has not descended by 6 months after birth, there is little chance for it to descend on its own. 6 months to 1 year old children can try hormone treatment, and those who do not succeed in hormone treatment should undergo testicular fixation surgery. Cryptorchidism treatment must be completed before 2 years old.
The main component of HCG is luteinizing hormone (LH), which stimulates the interrogated stromal cells to produce testosterone, and the concentration of testosterone in the testis increases, causing the germ cells to transform into Ad-type spermatogonia. Early healing, etc. Luteinizing hormone-releasing hormone (LHRH) or gonadotropin-releasing hormone (GnRH) can also be used for treatment, which has few side effects.
The dose of applying HCG: 2 times a week, l 000-1500IU each time, intramuscular injection, 9 times in a row as a course of treatment. lHRH can already be administered by nasal mucosal spray, 200#9 in each nostril 3 times a day, total l.2m9 per day, for 28 days. The application of LHRH before and after surgery can improve the histological structure of cryptorchidism. The effect of hormone treatment is closely related to the location where the cryptorchid is located, and the lower the location, the better the efficacy.
3.2 Testicular fixation is the main treatment therapy for cryptorchidism, and the combined inguinal hernia can be treated along with the surgical treatment.
(1) Standard surgical treatment: The main steps include oblique inguinal incision, repairing the hernia sac and freeing the testis and spermatic cord, then placing the testis into the scrotum and fixing it, paying attention to the tension-free spermatic cord after fixing the testis and ensuring the blood flow of the testis during the operation.
(2) Fowler-Stephen operation: This is an operation to cut off the blood vessels of the spermatic cord and relocate the testis downward. It is suitable for partial intra-abdominal high cryptorchidism and those whose vas deferens is long and curved in the inguinal canal.
(3) Staged surgery: that is, the first stage is to cut off the spermatic cord blood vessels and the second stage is to move down the testis.
(4) Testicular autotransplantation: In a few cases of high intra-abdominal cryptorchidism, the blood vessels of the spermatic cord can be cut off, and the arteries and veins of the spermatic cord can be anastomosed with the deep arteries and veins under the abdominal wall and the testis can be placed in the scrotum.
(5) Laparoscopic treatment: It is especially suitable for patients with high cryptorchidism. If the blind end of the vessel is seen along the spermatic cord, it can be determined that the testis is absent. If there is a nodule at the blind end, it should be removed and sent for pathological examination.
If a high intra-abdominal cryptorchid and a long vas deferens are observed during the examination, Fowler-Stephen surgery can be performed if the spermatic cord cannot be free to pull down the testis, and staged testicular fixation is also possible. In the first stage of surgery, the spermatic cord vessels are separated, clamped and severed, and the second stage of testicular fixation is reserved for later.
3.3 Postoperative management
Infusion and anti-infection.
4. Prevention and treatment of postoperative complications
4.1 Testicular atrophy: mostly caused by intraoperative damage to the spermatic cord vessels. Avoid damaging the spermatic vessels as much as possible during the operation.
4.2 Testicular retraction: mostly caused by excessive tension during descent. It can be descended in stages or freed as much as possible until there is no tension.