Uterine adhesion

　　The normal uterine cavity is in contact and closed in a physiological state, and even during the menstrual period, there will be no adhesion of the endometrium, which is due to the integrity and normal function of the basalis layer of the endometrium. If the endometrium is stimulated and damaged by physical and chemical factors such as surgery or inflammation, causing the destruction of the basalis layer of the endometrium and changing the regular growth and shedding of the endometrium during the normal menstrual cycle, it can lead to the extravasation and precipitation of fibrinogen in the uterine stroma, causing adhesion between the anterior and posterior walls of the uterine cavity.

　　The main causes of uterine cavity adhesion include:

　　1.History of uterine cavity operation

　　(1) Pregnancy factors: Uterine cavity surgery related to pregnancy, such as early pregnancy vacuum aspiration, mid-pregnancy curettage, mid-pregnancy induction abortion curettage, postpartum hemorrhage curettage, and spontaneous abortion curettage. This may be due to the fact that the endometrial basal layer of the pregnant uterus is more easily damaged, leading to mutual adhesion of the uterine wall and the formation of permanent adhesion.

　　(2) Non-pregnancy factors: Myomectomy (entering the uterine cavity), submucosal myoma resection by uterine cavity resection, excision of uterine septum, bicornuate uterus correction, etc., which destroy the basal layer of the endometrium, expose the uterine muscle layer to the uterine cavity, and lead to anterior and posterior adhesion of the uterine wall.

　　(3) Man-made factors: The occurrence of uterine cavity adhesion is due to man-made destruction of the endometrial basal layer. For example, adhesions caused by endometrial resection by electrical cutting, microwave in the uterine cavity, and freezing and chemotherapy after treatment.

　　2.Surgical inflammation factors

　　Intrauterine infection, uterine tuberculosis, postmenopausal senile endometritis, secondary infection after uterine cavity operation, puerperal infection, and secondary infection caused by the placement of intrauterine contraceptives, etc.

　　3.Man-made factors

　　Some women have uterine cavity adhesion caused by man-made factors. Man-made destruction of the endometrial basal layer leads to uterine cavity adhesion. For example, after uterine cavity microwave, endometrial resection by electrical cutting, freezing, chemotherapy, and local radiotherapy.

　　4,Endometrial injury during curettage due to various reasons

　　For example, repeated刮宫, this is very easy to damage the basal layer, and the adhesion in the uterine cavity caused by this reason is called traumatic adhesion, which is the most common. Therefore, obstetricians and gynecologists should moderate the depth of curettage, and childbearing women should implement good contraception measures, avoid abortion surgery, especially the first-trimester abortion may cause uterine cavity adhesion and secondary infertility thereafter.

　　The main symptom of uterine cavity adhesion is decreased menstrual flow or amenorrhea. In patients with uterine cavity adhesion, the incidence of secondary infertility is extremely high, reaching above 86%.

　　1) Unfavorable for sperm survival and implantation of the embryo: The scar tissue and uterine cavity occlusion caused by adhesion in the uterine cavity disrupt the integrity of the endometrial layer, leading to dysregulation and disorder of the physiological function of the endometrium, which is very unfavorable for sperm storage, survival, and capacitation, as well as for the implantation of the embryo, placental implantation, and embryo development, thus leading to infertility and abortion.

　　2) Concomitant tubal obstruction and adhesion, leading to blocked fallopian tubes. Adhesion in the uterine cavity often occurs concomitantly with tubal obstruction and adhesion, due to congestion, edema, thickening, and hardening of the fallopian tubes, forming adhesions, narrowing, and eventually obstruction of the tubes. This results in blocked or partially blocked fallopian tubes, preventing the normal and smooth combination of sperm and egg, leading to infertility.

　　Uterine cavity adhesion is caused by scar formation after recent uterine injury, about 90% of cases are caused by curettage. Usually, the injury occurs within 1-4 weeks after term delivery, preterm delivery, or post-abortion, and curettage is required due to a large amount of vaginal bleeding. Uterine cavity adhesion can usually cause menstrual abnormalities, such as oligomenorrhea, and severe adhesions can cause amenorrhea. If part of the uterine cavity is sealed off, the patient may become pregnant, but it is easy to have a miscarriage, preterm delivery, ectopic pregnancy, intrauterine fetal death, placental implantation, and placental adhesion, and infertility may occur in patients with complete closure. Uterine cavity adhesion can be classified into endometrial adhesion, fibromuscular adhesion, and connective tissue adhesion. The diagnosis of uterine cavity adhesion used to be made with fallopian tube iodine oil contrast or ultrasound, but for some mild adhesions, it is easy to miss the diagnosis, and it cannot indicate the tenacity and type of adhesion. The treatment of uterine cavity adhesion often involves dilation with a dilator, and an intrauterine device is placed after dilation. However, this operation is blind and cannot restore the original uterine cavity shape, and the recurrence rate of adhesion is high.

　　When adhesion of the uterine cavity due to ectopic pregnancy appears with amenorrhea and lower abdominal pain, it should be differentiated from ectopic pregnancy. The former has a history of induced abortion or curettage, and the pain is mainly periodic. Although there may be tenderness or rebound pain in the lower abdomen, there are no symptoms of internal bleeding or shock, and the uterine probe or hysteroscope examination can usually confirm the diagnosis. When the menstrual blood flows out smoothly during the exploration, the symptoms of abdominal pain are immediately relieved or disappear. Ectopic pregnancy patients often have symptoms and signs of internal bleeding after abdominal pain, and transvaginal puncture is often used for diagnosis.

　　Endometriosis can cause dysmenorrhea, which is also a periodic abdominal pain that worsens progressively, but menstrual blood排出 smoothly, and the symptoms of abdominal pain do not subside after menstrual blood flows out; while the abdominal pain caused by uterine cavity adhesion is obstructive dysmenorrhea, the symptoms can be immediately relieved or even disappear after the cervix is dilated to allow menstrual blood to flow out. It can also be distinguished from the history, as endometriosis is often associated with infertility, while uterine cavity adhesion often occurs after induced abortion.

　　Amenorrhea after early pregnancy aspiration or curettage should also exclude early pregnancy. Early pregnancy generally has no history of abdominal pain, but often has a history of pregnancy reactions. Uterine enlargement usually corresponds to the gestational age, and a positive urine pregnancy test is often helpful for diagnosis.

　　For those with amenorrhea and no or mild abdominal pain after adhesion of the uterine cavity, it is necessary to differentiate from hypothalamic or pituitary amenorrhea, early ovarian failure, and other conditions. Amenorrhea caused by uterine adhesion may not recover after treatment with progesterone, estrogen, or artificial cycles, while basal body temperature measurement, cervical mucus crystallization, and vaginal exfoliated cell smear examination all show normal ovarian function.

　　1. Before surgery, the patient's chronic cervicitis and endometritis should be actively treated to prevent postoperative infection.

　　2. If it is found that the cervix needs to be dilated, it should not be done roughly, and the dilator should not be skipped to avoid injury to the cervical canal.

　　3. The negative pressure during aspiration should be appropriate, and the negative pressure should be turned off when entering and exiting the cervix.

　　4. Methods for detaching adhesions can include the use of a probe or small dilator, and it can be effectively achieved by placing an intrauterine device. Some people also apply adrenal cortical hormones to prevent fibrosis, or estrogen and progesterone for artificial cycles to effectively treat the condition.

　　5. Family planning, reducing the number of induced abortions and cesarean sections. Pay attention to aseptic operation during induced abortions and curettage to prevent excessive aspiration and trauma to the cervical canal.

　　Hysteroscopy

　　Advantages of hysteroscopic examination

　　(1)High diagnostic accuracy rate.

　　(2)It can determine the degree and type of uterine adhesions and evaluate the effectiveness of other treatment methods.

　　(3)Surgical resection of uterine adhesion under direct vision is safe and convenient, more effective and thorough than blind scraping or abdominal uterine incision. As the hysteroscope only cuts the scar without destroying the endometrium, it is beneficial for postoperative recovery.

　　(4)Hysteroscopic adhesiolysis (hysteroscopiclysis of adhesions) can be performed under local anesthesia, reducing the risk of anesthesia and surgical costs.

　　(5)Convenient for follow-up, allowing for accurate and rapid assessment of the surgical outcome.

　　(6)Recovery of normal menstrual flow is possible.

　　(7)Guidance on contraception and conception time based on the surgical outcome.

　　Key points of hysteroscopic examination

　　During hysteroscopic diagnosis of uterine adhesions, the hysteroscope should carefully observe the internal os of the cervix and the adhesion bands at the isthmus. After entering the uterine cavity, one should first observe the overall shape of the uterine cavity from far to near, and then further observe local lesions after finding any abnormalities. It is crucial not to enter the uterine cavity with the hysteroscope only once, as this may result in only observing local areas without the overall shape of the uterine cavity, often leading to incorrect conclusions. When abnormal shapes are found during hysteroscopic examination, it is necessary to differentiate from diseases such as uterine malformations, incomplete abortion, and foreign body retention.

　　Hysteroscopy for determining the type

　　(1)Classification according to the site of adhesion

　　①Central adhesions: The adhesions are located between the anterior and posterior walls of the uterus, adhering the central part of the uterine cavity.

　　②Peripheral adhesions: The adhesions are located at the fundus or lateral wall of the uterus, adhering the peripheral part of the uterine cavity. Particularly, within the cornua uteri, they cause cornual atresia, making the fallopian tube orifice invisible.

　　③Mixed adhesions: This is a combination of central and peripheral adhesions.

　　Hysteroscope image of the uterine cavity

　　(1)Endometrial adhesions: The surface of the adhesion is very similar to the surrounding endometrium, mostly white, soft, band-like structures connected to the anterior and posterior walls of the uterus. When extensive, they can present a 'harp' or 'curtain'-like shape. The adhesions are generally fragile and soft, easy to separate, and sometimes can be broken with low-pressure lavage fluid alone. The residual ends of the separated adhesions generally do not have active hemorrhage, and appear to float and sway like aquatic plants in the lavage fluid. This type of adhesion is predominantly central in type.

　　(2)Muscle adhesions: The color of the adhesion image is the same as the uterine muscle layer, pink. The endometrium covering the fibromuscular adhesion also has functional changes, with many gland openings visible on the surface during the secretory phase. The adhesions are often cylindrical, tough, and elastic. The断面 after severance is rough, red, with visible bleeding or active hemorrhage.

　　(3)Adhesions of connective tissue: The surface is slightly grayish-white with a glossy appearance, without endometrial covering, and significantly different from the surrounding endometrium. It is tough and hard, often large and irregular in shape. The断面 after separation is rough, resembling a broken tree trunk, pale without bleeding.

　　(2) Uterine iodine oil contrast

　　In the past, when hysteroscopy was not widely used, uterine iodine oil contrast was the main diagnostic basis for uterine adhesion. Uterine iodine oil contrast can indeed obtain positive X-ray signs, including irregular filling defects, uterine deformation, or irregularity. However, mild and sparse adhesion bands are often missed on HSG films, and bubbles, blood clots, and uterine endometrial fragments can also cause filling defects, leading to misdiagnosis. In addition, the operator's technical skills and experience in reading films can also affect the accuracy of diagnosing uterine adhesion.

　　The characteristics of uterine iodine oil contrast are:

　　(1) There may be one or more clear contours, sharp edges, and abnormal shapes, irregular shadowing of filling defects in the uterine cavity, which do not change with the pressure or amount of contrast agent injected.

　　(2) The local edge of the uterine cavity is irregular.

　　(3) Fine reticular vascular images often appear, which is due to excessive pressure of iodine oil injection during contrast, causing iodine oil to enter the uterine blood vessels from the peeled surface.

　　(4) In some cases of uterine adhesion, the uterus may be highly flexed forward or backward, causing the uterine cavity and cervical image to overlap and become unclear. The uterus appears olive-shaped. In such cases, the cervix can be pulled with a cervix clamp to extend the uterus, and the uterine image can change from olive-shaped to triangular. To prevent chronic inflammation caused by oil embolism and oils, water-soluble contrast agents can also be used. Mild adhesions can be separated through contrast imaging.

　　(3) Hysteroscopy

　　For patients highly suspected of having uterine adhesion, the sound can be used for examination after disinfection. If there is adhesion at the cervical canal or the internal os of the uterus, the sound may encounter resistance and be difficult to penetrate into the uterine cavity after being inserted 3-5 cm into the cervical canal; if there is uterine adhesion, the sound may feel narrow or asymmetric during the examination. Since this procedure requires a high level of the operator's surgical skills and experience, it is a 'blind exploration' with poor repeatability and directness, and its reliability varies from person to person. Therefore, it is generally not used as a routine diagnostic method in clinical practice.

　　During hysteroscopy, the uterine sound is inserted about 1-3 cm into the cervical canal, where resistance is felt, with about 2 cm being the most common. The resistance can vary depending on the adhesion tissue; it is very easy to insert the sound into endometrial adhesions; when muscular layer adhesions are present, it is necessary to apply slight force in the direction of the uterus to insert the sound; if resistance is felt and the tissue is tough, do not use excessive force to avoid causing uterine perforation. After the sound enters the uterine cavity, it can be swept in a fan shape to the left and right to test the size of the uterine cavity and the extent of adhesion. In severe cases of adhesion, the uterine cavity may feel like a narrow tube, with a very small range of movement for the sound, or it may not be able to enter at all.

　　1. The diet should be light and non-greasy, avoiding foods that can cause heat, such as mutton, shrimp, crabs, eel, salted fish, and blackfish.

　　2. It is prohibited to eat spicy foods such as chili, Sichuan peppercorns, raw scallions, raw garlic, and white wine, as well as stimulating beverages.

　　3. It is forbidden to eat foods with heat, coagulation, and hormone components such as longan, jujube, mastic, and royal jelly.

　　4. It is recommended to consume lean meat, chicken, eggs, quail eggs, crucian carp, turtle, whitefish, cabbage, asparagus, celery, spinach, cucumber, winter melon, mushrooms, tofu, seaweed, laver, and fruits, among others.

　　Therefore, patients with uterine adhesion should pay attention to light diet in food, do not eat mutton, crab, shrimp, salted fish, eel, black fish and other irritants, and do not eat Sichuan peppercorns, chili, raw garlic, raw scallion, white wine and other irritant foods. Otherwise, it may worsen the disease and cause unnecessary harm.

　　Uterine adhesion separation surgery

　　Using surgery to separate the adhesion and blockage of the uterine cavity. Generally, it should be performed under hysteroscopy to determine the location and degree of adhesion, and can preliminarily judge the histological characteristics, especially helpful for guiding the accuracy, safety and thoroughness of surgery. The mild ones can be separated with a probe; the severe ones need to use curved forceps, scissors or electrical cutting. After the operation, an intrauterine contraceptive device should be placed to prevent re-adhesion, and artificial cycle estrogen supplement treatment should be carried out to promote endometrial hyperplasia and repair.

　　The treatment of uterine adhesion in traditional Chinese medicine is based on the characteristics of uterine adhesion, adopts high-tech, uses the dialectical treatment of traditional Chinese medicine, and is配合 with unique Chinese medicine formula, promotes the absorption and regression of inflammation.

　　Surgical separation of adhesion

　　1. Separation of adhesion with a probe After the probe is separated left and right, cervical dilation is performed. If the adhesion is tight, in order to prevent uterine perforation, the operation can be performed under the guidance of B-ultrasound.

　　2. Separation of adhesion under hysteroscopy After the adhesion is separated by surgery, an appropriate size intrauterine device can be placed in the uterine cavity, and it can be removed after 3 months to prevent re-adhesion. In addition, artificial cycle treatment can be carried out for 3 months to promote endometrial hyperplasia and repair.

　　Preoperative preparation

　　1. Routine preparation should first be clear diagnosis, understand the location, nature and degree of adhesion. If the cervical canal adhesion is complicated with uterine hemorrhage, it should be treated as soon as possible to prevent further increase of hemorrhage; if B-ultrasound shows thin endometrium without cyclical changes, artificial cycle treatment can be adopted to promote endometrial hyperplasia, which is conducive to distinguishing normal endometrium from adhesion band during surgery.

　　2. Surgical instruments

　　(1) Therapeutic hysteroscope or uterine resectoscope. Some thin membrane-like adhesions can sometimes be broken simply with the sharp edge sheath at the tip of the hysteroscope.

　　(2) Sharp edge biopsy forceps or miniature scissors.

　　(3) B-ultrasound or laparoscopic monitoring system, commonly used in cases with severe uterine adhesion and estimated difficult surgery.

　　Surgical anesthesia

　　Whether to choose anesthesia depends on the degree of uterine adhesion and the difficulty of surgical operation. If the estimated operation time is not long and the operation is simple, anesthesia may not be required or short-acting, rapid-recovery intravenous anesthesia may be chosen. If the uterine adhesion is severe and the operation is estimated to be time-consuming and laborious, continuous epidural anesthesia or general anesthesia may be adopted.

　　Surgical procedure

　　1. Dilate the cervical canal

　　Some cervical canals or internal os are粘连狭窄，uterine probes cannot be inserted into the uterine cavity. This step must carefully determine the position of the uterus, understand the curvature between the cervix and the corpus, and under the monitoring of B-ultrasound, start to dilate the cervical canal with No. 1 (1mm outer diameter) Hegar dilator, probe and insert slowly and cautiously, until it can be inserted into the uterine cavity. Most cervical canals or internal os adhesions have reached the therapeutic goal through this step. It is also possible to separate the inner os of the uterus and the loose adhesion band between the isthmus under hysteroscopy.

　　2. Separation of Adhesed Uterine Cavity

　　After the hysteroscope is located, separation can be performed under direct vision. (1) Membranous adhesions: The edge of the hysteroscope tip or sheath can be used to push, elevate, and peel off the adhesions within the uterus with moderate force. Miniature scissors can also be placed through the operating channel to cut the adhesions. (2) Myofibrous and connective tissue adhesions: uterine resection hysteroscope or laser fiber ablation of adhesions is required. The closed-type anterior oblique circular electrode of the uterine resection hysteroscope is used to cut the adhesions, and if the uterine cavity is completely closed, it should be cut upwards from the internal os of the uterus until the new uterine cavity is formed. When cutting adhesions near the uterine cornua, great care must be taken not to cut too deeply, as the uterine muscle wall is very thin and it is easy to cause uterine perforation.

　　3. Separation Skills

　　(1) Simple Cervical Canal and Internal Os, Isthmus Adhesions: For complete cervical canal and internal os adhesions that are closed but the uterine endometrium is intact, clinical manifestations often include amenorrhea and periodic lower abdominal pain after hysteroscopic surgery; if it is incomplete adhesion closure, there is often a complaint of scanty menstruation accompanied by dysmenorrhea. If necessary, follow-up can be conducted 2 to 3 months after cervical dilation, in addition to understanding the menstrual and abdominal pain situation, hysteroscopy can also be performed to understand whether there are any abnormalities in the uterine cavity, and if there is a desire for pregnancy, hysterosalpingography and catheterization can be performed at the same time for treatment.

　　(2) Uterine Adhesion: In principle, mechanical methods (such as the edge of the end of the hysteroscope, miniature scissors, sharp biopsy forceps, etc.), circular electrodes, or lasers should be used under the direct vision of the hysteroscope to separate the adhesions within the uterine cavity, restore the uterine cavity to a symmetrical normal shape, and be able to display both fallopian tube orifices. For severe adhesions that cause the uterine cavity to close, the adhesions should be sequentially cut from the level of the internal os, finally reaching the fundus and cornua. For cornual adhesions that close the cornua, they can be stripped apart using biopsy forceps and shaped as much as possible, and large pieces of adhesions mixed in the uterine cavity should be removed as much as possible.

　　Successful Surgery

　　The standard for successful surgery should be the restoration of the normal size and shape of the entire uterus, and the bilateral fallopian tube orifices should be clearly visible. The objective lens can be retracted to the internal os of the cervix to observe the symmetry of the uterine cavity. If laparoscopic monitoring is available, methylene blue solution can be injected into the uterine cavity through the cavity to perform a fallopian tube patency test.