Chronic pelvic pain

　　1. Etiology

　　Chronic pelvic pain is a multifactorial issue, and there is no simple etiology that can explain it, hence an accurate diagnosis is not easy. Although people have some understanding of the pain caused by many visceral injuries, there is little knowledge about the relationship between pelvic organ injury and pain in women. At least one-third of the patients with CPP cannot find a clear cause even after laparoscopic examination. In addition, the distortion of pelvic organs caused by adhesions and endometriosis does not necessarily cause pain. Even if pain is caused, the location and severity may not be correlated with the location and severity of the lesion. Moreover, compared with acute pain, CPP may have different sensory, emotional, and behavioral responses.

　　1. Chronic pelvic pain (CPP) is a symptom. Some patients can find the cause such as chronic pelvic inflammatory disease, endometriosis, adenomyosis, pelvic adhesions, and other organic lesions, but many patients only have minor pathological changes or no organic changes. For such patients, some explanations can be obtained from the social-psychological aspects. Doctors often diagnose functional chronic pelvic pain, but according to the theory of modern biopsychosocial medical model, it should be called psychological (mental) chronic pelvic pain. Some Chinese scholars have conducted investigations, and the causes of CPP are attributed to social psychological factors accounting for 5% to 25% of the total.

　　2. Stout et al. evaluated 294 CPP patients using the CES-D self-report scale for epidemiological depression symptoms, finding that 59% of the women scored within the depression range (total score ≥ 16 points). Scloulmb et al. found that CPP patients scored higher in anxiety, depression, anger/enmity, and somatic symptoms using the Hopkins symptom scale. However, 56% of the women scored within the normal range, so it is unclear whether psychological abnormalities are the cause of the disease or the result of pain.

　　3. Some CPP occurrences are also related to traumatic sexual experiences. Reiter et al. found that 48% of the 106 CPP patients had traumatic sexual experiences, including sexual harassment, incest, or rape, while only 6.5% of the 92 controls had such experiences (P < 0.01). The incidence of sexual trauma in the childhood CPP group was also higher than that in the control group (64% / 23%), and there were no qualitative or quantitative differences in the laparoscopic examinations of the two groups.

　　4. Some studies believe that the occurrence of CPP is related to unhappy marriage and sexual dysfunction. Stout once tested 220 married CPP patients with the Locke-Wallace marital status assessment scale, finding that 56% scored less than 100 points, indicating marital distress.

　　Second, Pathogenesis

　　To date, there are still many controversies about the neurophysiology and pharmacology of pelvic pain, which is also a hot topic of research. Although the neural conduction mechanism of acute pelvic pain has been determined, the sensory conduction mechanism of CPP is still not clear.

　　The neuroanatomy, neurophysiology, and pharmacology of acute pelvic pain:

　　1. Visceral pain and somatic pain: Visceral pain refers to the pain sensation caused by internal organs such as intestines, bladder, rectum, uterus, ovaries, and fallopian tubes, and its corresponding counterpart is somatic pain, which refers to the skin, fascia, and muscles such as external genitalia, anus, urethra, and parietal peritoneum. Unlike somatic pain, visceral pain is difficult to locate and usually manifests as cutting, squeezing, or burning sensations. Although it appears as somatic pain, it is usually not located in the affected visceral organs. Clinical studies have proven that the causes of visceral pain include:

　　(1) Expansion or abnormal contraction of the muscle of hollow visceral organs, such as uterine contraction during childbirth;

　　(2) Sudden traction of the capsule of solid viscera, such as the rupture of a hemorrhagic ovarian cyst;

　　(3) Visceral hypoxia or necrosis, such as torsion of the ovaries or degeneration of uterine fibroids;

　　(4) Secretion of pain-causing substances, such as the secretion of prostaglandins during dysmenorrhea and endometriosis;

　　(5) Chemical stimulation of visceral peripheral nerves, such as the overflow of oily content when a cystic teratoma ruptures;

　　(6) Sudden compression of ligaments or blood vessels;

　　(7) Inflammation, such as appendicitis. In addition, the sensitivity of the viscera to pain varies greatly. The pain threshold is the lowest in serous membranes, followed by muscles, and the highest in solid organs. The external genitalia are rich in somatic nerves and are very sensitive to pain, making the localization of pain easy.

　　The neural conduction mechanism of visceral sensation is different from that of the somatic nervous system. Compared with somatic nerves, visceral nerves have a very low or lack of myelin sheath content, and a slower conduction speed. Visceral nerves are thin aδ and C class nerve fibers. Unlike somatic nerves, these afferent nerves may not have pain receptors or lack high-threshold specialized nerve endings, so they do not feel specific pain after being stimulated. Instead, they terminate at mechanoreceptors, which have the ability to gradually respond to the intensity of the stimulus. Therefore, the information transmitted from the visceral nerve endings to the central nervous system is not a specific harmful (painful) stimulus, but it indeed reflects a painful stimulus. It identifies harmful stimuli through the intensity of secretion by peripheral nerves, and the spinal cord and central nervous system also participate in the processing of the signal. Therefore, visceral pain is a series of complex neural reflexes caused by mechanical or chemical stimulation of the viscera and regulated by the central nervous system. The density of visceral nerves is much lower than that of somatic nerves, so the sensory range is large and the localization is inaccurate. Some scholars have studied the neural distribution in cats and estimated that in the spinal cord afferent nerves, the visceral afferent nerves are only 1.5% to 2.5% of the somatic afferent nerves.

　　People traditionally divide visceral pain into two types: true visceral pain and reflexive visceral pain. True visceral pain, such as the pain at the onset of ovarian torsion, is widespread in range, deep in location, and usually accompanied by other autonomic reflexes such as nausea, sweating, and fear. Unlike reflexive visceral pain, it does not have progressive increased skin pain sensitivity (allodynia). Reflexive visceral pain refers to pain that occurs on the skin away from the viscera after the viscera are stimulated by harmful stimuli. The location is usually clear and superficial, and can be inferred from the distribution map of the sensory nerve ganglia of the spinal cord. The skin area controlled by a single spinal nerve is called a dermatome. Each body site has at least nerve axons distributed from 5 different spinal nerve dorsal columns, so the size of the dermatome depends on the interaction between the primary afferent nerve fibers and the secondary neurons in the spinal cord dorsal horn. The actual pain location of pelvic organs depends on the spinal segment of the corresponding visceral afferent nerve.

　　The mechanism of reflex visceral pain is still controversial. The sensory nerve fibers of visceral and somatic organs terminate in the same secondary neurons in the dorsal horn of the spinal cord. In addition, the afferent nerves from a widespread area of visceral and somatic organs converge within a spinal segment, which is likely the basis for the occurrence of visceral reflex pain. The cutaneous hyperalgesia accompanying visceral reflex pain may belong to visceral-cutaneous reflex or visceral-muscle reflex. This neural reflex will stimulate the muscles, fascia, and subcutaneous tissues under the skin segment, resulting in true somatic pain. The cause of muscle pain may be muscle contraction, and the subcutaneous pain may be secondary to the retrograde transmission of noxious chemicals by peripheral afferent nerves. Therefore, visceral reflex pain has two meanings: first, the pain occurs in a clearly normal area far from the visceral organ, and secondly, due to the hyperalgesia of the skin in this area, even superficial stimuli without obvious injury can cause pain in this area or even the skin segment.

　　The sensory innervation of the pelvic organs comes from the autonomic nerve trunks, with the cell bodies of sympathetic nerve fibers distributed in the thoracic and lumbar spinal cord, while the cell bodies of parasympathetic nerve fibers are in the sacral dorsal ganglion. Both of these visceral afferent nervous systems participate in visceral sensation and reflexes. The sensory nerves of female pelvic organs are mainly sympathetic nerves, and the specific sensory innervation of an individual pelvic organ depends on its embryonic origin. From the perspective of embryology, the reproductive organs can be divided into three categories: the gonads from the urogenital ridge, the uterus, ovary, fallopian tube, and upper segment of the vagina from the Müllerian duct, and the lower segment of the vagina and the vulva from the urogenital sinus.

　　The anterior part of the vulva, including the clitoris and the anterior part of the urethra, is innervated by a mixed somatic nerve (sensory and motor nerves), derived from the lateral branches of the ventral and dorsal roots of the 1st to 2nd lumbar spinal segments. The dorsal root nerves originate from the 1st to 2nd lumbar vertebrae, innervating the lumbar sacral region, which is usually the reflex pain area of gynecological pain. The perineum, anus, and lower segment of the vagina are innervated by the somatic branches of the pudendal nerve, originating from the 2nd to 4th sacral nerve roots. The pain stimuli from the upper segment of the vagina, cervix, corpus, uterine tube, lateral ligament, upper part of the bladder, cecum, vermiform appendix, and distal colon are transmitted to the sympathetic trunks of the thoracic and lumbar spinal cord via the sympathetic nerves of the lower abdominal plexus, which then enter the thoracic 11-12 and lumbar 1 spinal cord through the dorsal roots of these nerves.

　　From the superior segment of the vagina, cervix, and lower segment of the uterus, the nerve impulses were previously thought to enter the sacral 2-4 through the parasympathetic nerves of the pelvic nerves, but there is still controversy about this. The first stage of labor for parturients is the process of cervical dilation, traction, and tearing. The research on analgesia for all stages of labor using Bonica's nerve block anesthesia suggests that although the pain reflexes to the sacral 2-4 dermatomes in the early stages of labor, the conduction of pain during the first stage of labor is through the uterine plexus, inferior abdominal plexus to the inferior abdominal nerve, and then through the superior abdominal plexus into the sympathetic trunk of the lumbar and sacral and lower thoracic spinal cord. As mentioned before, the visceral reflex pain in the lumbar and sacral region is regulated by the cutaneous branches of the lower thoracic and upper lumbar spinal nerves, which are distributed in the lower lumbar and sacral regions. When the second stage of labor is nearing completion, the pain is mainly from the stretching, traction, and tearing of the perineum. Blocking the pudendal nerve (somatic sacral nerve) can alleviate the pain. However, considering the embryonic origin, at least part of the vagina is derived from the urogenital sinus, bladder, and rectum as well. Therefore, the afferent nerves of the vagina, in addition to those entering the thoracic and lumbar spinal cord as mentioned above, may also enter the sacral spinal cord. Rat pelvic nerve resection experiments have confirmed this point. It seems that the afferent nerves of the thoracic and lumbar spinal cord and sacral spinal cord are doubly innervated. The afferent nerves of the ovary accompany the ovarian artery and enter the sympathetic trunk from the sympathetic ganglion of the fourth lumbar vertebra, then ascend along the sympathetic trunk and enter the spinal cord at the level of thoracic 9-10. The nerve supply of the outer two-thirds of the fallopian tube and the upper segment of the ureter is similar to that of the ovary. The superior abdominal plexus and the inferior mesenteric plexus do not contain the afferent nerves of the ovary and the lateral fallopian tube. This can explain why the resection of the sacral nerve (superior abdominal plexus) can only alleviate the pain in the middle pelvic (uterus) but cannot eliminate the pain from the adnexa (ovary). Therefore, the conduction of pain stimuli from pelvic organs depends on a complete sympathetic innervation system, and the complete afferent and efferent systems of the sacral nerve are the key to the normal function of the reproductive organs, colon, and bladder. Pelvic nerve resection affects normal urination and defecation functions. However, if only the sympathetic nerves of the pelvic area are resected, it does not affect the intestinal tract, bladder, and reproductive functions, and has no serious impact on the visceral sensation of the intestines and bladder. The above nerve structures make the sensory neurons the first station of many signal transfer stations, thereby transmitting the signal of the pain sensation of pelvic organs to the brain. The cell bodies of the afferent axons of the传入 nerves are located in the spinal nerve sensory (dorsal) root ganglion, and the axons are branched, merging into the spinal cord. The terminal ends of the axons divide into ascending and descending branches, which extend into the upper and lower spinal cord segments respectively. Many ascending and descending branches become part of the Lissaure tract (Lissaure Tract), that is, the dorsal lateral tract, located on the dorsal side of the spinal cord gray matter. According to the appearance of the spinal cord gray matter and the density of neurons, the dorsal horn of the spinal cord gray matter forms a neural plate, which is arranged in order from the dorsal to the central neural plate, starting from the Lissaure tract. The afferent axons of the viscera enter the spinal cord gray matter through the first, 5-8, and 10 neural plates of the dorsal horn. The somatic支配 nerves enter the spinal cord gray matter through the 2-4 neural plates.

　　As mentioned earlier, modern research indicates that the axons of visceral and somatic nerves converge at the secondary neuron site in the dorsal horn of the spinal cord. However, there seems to be no specific spinal neuron that is solely responsible for the signals of visceral transmission. There are some somatic neurons in the dorsal horn of the spinal cord that can be activated by stimulating a specific dermatome of the skin tissue, but they do not receive signals from visceral传入 nerves; there are also some visceral-somatic nerve cells that are responsible for processing signals conducted by both visceral and somatic nerves. The functions of these secondary visceral-somatic neurons within the spinal cord can be either excitatory or inhibitory. For example, the intensity of the neural response caused by simultaneous stimulation of both the skin and visceral nerve endings is greater than that caused by stimulation of either the skin or the viscera alone. Conversely, under the premise of existing skin stimulation, the neural cell response to visceral stimulation will weaken. The visceral-somatic neurons have a wider range of sensation compared to somatic neurons, usually including three or more dermatomes. Moreover, the afferent nerves related to both visceral and somatic functions often intersect and overlap in the dorsal horn, for example, the visceral nerves that支配 bladder and rectum and the somatic pudendal nerves that支配 urinary bladder and anal sphincter are intersecting and overlapping in the dorsal horn of the spinal cord. Perhaps it is this special and orderly connection between the primary visceral-somatic nerves and the secondary neurons in the dorsal horn of the spinal cord that ensures the central nervous system correctly decodes the incoming signals. The central decoding mechanism refers to the identification of specific and different sensations, including the activation of various appropriate neural reflexes, the mechanism of which has not been elucidated but may be related to the gate theory. It can be influenced by the level of emission of visceral afferent neurons, the afferent signals from the skin and deep somatic tissues, the endogenous opiate and non-opiate pain systems, and the various central stimulatory or inhibitory influences from the brainstem, hypothalamus, and other parts of the brain. The spinal tractotomy and the spinal small nerve bundle located in the anterior-lateral quadrant of the spinal cord are the main ascending pathways within the spinal cord for transmitting somatic and somatic-visceral information to the brain. The spinal tractotomy ends at the thalamic nucleus, after which the information continues to be transmitted forward to the somatosensory center of the cerebral cortex. The spinal small nerve bundle ends at the reticular structure of the brainstem, which may trigger wakefulness, and is related to the neural activity of the emotional aspects of pain, as well as somatic and autonomic motor reflexes. The reticular structure projects downwards into the spinal cord and may be an important inhibitory regulatory mechanism for pain stimuli, and may also be a major component of the endogenous pain system. Although many signals seem to enter the anterior quadrant of the spinal cord, in many cases, the pain sensation will recover several months or years after the complete resection of this part of the spinal cord. The mechanism of pain recovery may be due to the change in the conduction pathway of pain, with some pathways with the potential to transmit pain information beginning to take effect. The dorsal pain receptors in the spinal cord may play a certain role. In humans, the understanding of this terminal conduction pathway is almost a blank.

　　3. The neural pharmacology of visceral传入neurons is represented by aδ and C neurons, which can synthesize various neurotransmitters or peptides and then be transported to the central or peripheral nerve endings for release (retrogradely). Studies using cat models by DeGrout have found that most visceral传入neurons contain neuropeptides, primarily vasoactive intestinal peptide (VIP) accounting for 20% to 60%, leucine enkephalin accounting for 30%, substance P accounting for 25%, cholecystokinin accounting for 29%, and methionine enkephalin accounting for 20%. While only a few somatic neurons contain these neuropeptides, a neuron can contain two or more types of neuropeptides, so these neuropeptides can participate in feedback inhibitory mechanisms, for example, the reduction of enkephalins can simultaneously reduce the release of excitatory neurotransmitters such as vasoactive intestinal peptide and substance P, thereby exerting an autonomic inhibitory effect. Moreover, traditional neurotransmitters such as catecholamines can coexist with neuropeptides within a single neuron, thus neuropeptides can regulate the release of traditional neurotransmitters, even modulate neurotransmitter receptors or postsynaptic membranes, acting to enhance or inhibit the action of neurotransmitters. In humans, for example, neuropeptides such as enkephalins, vasoactive intestinal peptide, and substance P are located in the smooth muscle layer of the viscera, connected to the visceral blood vessels. The cervix and urethra contain more E, while the vagina, bladder, cervix, uterus, fallopian tubes, spinal dorsal root ganglia, and dorsal horns contain substance P. The spinal dorsal root ganglia also contain cholecystokinin and bombesin-gastrin. However, it may be only substance P and vasoactive intestinal peptide that can be transmitted to the peripheral nerves, and the role of neuropeptides is not yet clear. It may be that they promote the transmission of pain, for example, substance P and VIP can cause vasodilation, and substance P can stimulate the secretion of histamine, increasing capillary permeability. It is very likely that these neuropeptides play a certain role in the interaction between sensory nerves, autonomic nerves, and blood vessels. Some speculate that increasing the intensity of neural stimulation can cause the retrograde release of neuropeptides, leading to the accumulation of peripheral nerve sensory fibers and the release of inflammatory mediators. Neuropeptides may play an important role at all levels of the spinal cord and brain visceral sensory conduction mechanisms. Although intrathecal injection of most neuropeptides can cause pain, it is not yet clear whether all these neuropeptides are endogenous pain modulators. The opiate family known as endorphins is the main pain-inducing neuropeptide, and it is known that enkephalins and dynorphins exist in the spinal dorsal horn, β-endorphins and enkephalins exist in the lamina and other parts of the brain, and it is possible that they play a major role in the processing of pain responses. Some believe that substance P is also an excitatory neurotransmitter in the central nervous system, and substance P is widely distributed in the spinal cord and brain, but there is no complete conduction pathway for it.

　　4. The perception of pain by the cerebral cortex and the influence of stress and depression on it. Pain can be divided into two parts: one is the cognitive aspect of sensation, that is, the localization of pain stimuli, and the other is the affective-motor aspect, that is, the sensations accompanying pain such as pain, discomfort, or anxiety. In the past, prefrontal lobotomy was used to treat intractable pain, and patients showed obvious changes in personality after the operation. Before the patient's attention was focused on the pain, they were indifferent, and could not feel the pain. Only when their attention was focused on the pain did they feel the pain, but almost no pain response or anxiety, that is, they did not complain or ask for painkillers. However, the pain threshold of these patients is not higher than that of normal people. This phenomenon, combined with other data, indicates that there are specific neural anatomical substances responsible for the cognitive and affective aspects of pain.

　　Perhaps the prefrontal cortex is involved in the cognition of pain, motor, and emotional activities because it receives almost all levels of sensory information and is closely connected with the cerebral cortex and the thalamus and cingulate structures. Cognitive and psychological factors such as childhood experiences, past conditions, other learning behaviors, worry, stress, attention, and cultural background can affect the range of pain perception, emotion, and behavior, especially worry, which is a strong regulatory factor that weakens pain tolerance. Motivation also affects the physiological and emotional aspects of pain. It is speculated that worry, stress, and depression can activate part of the brain, preventing or accelerating the transmission of harmful impulses from the dorsal horn of the spinal cord, different levels of the spinal cord, and the brain. However, the exact mechanism requires further study.

　　It is often accompanied by symptoms of autonomic nervous system dysfunction such as increased respiratory rate, sweating, rapid heart rate, and unstable blood pressure. Psychological factors may play an important role in the pathogenesis of the disease. Patients may have symptoms such as depression, suspicion, or anxiety. These patients may also manifest various psychological disorders, such as sleep abnormalities and personality disorders.

　　Chronic pelvic pain (CPP) is a non-specific term that includes gynecological diseases such as endometriosis, pelvic inflammatory diseases, pelvic adhesions, and pelvic venous congestion syndrome that are easily detected by laparoscopy, as well as some hidden somatic diseases (usually diseases outside of gynecology) such as irritable bowel syndrome, and also includes non-somatic (psychogenic) diseases.

　　First, symptoms and signs

　　Due to lower abdominal pain, pelvic pain is also called lower abdominal pain in clinical practice.

　　1. Lower abdominal pain or lower back pain:Lower abdominal pain can be in the entire lower abdomen, or in both or one side of the iliac fossa, or without clear localization. It is often accompanied by vaginal discomfort, and is usually a persistent or intermittent dull or hidden pain; the patient cannot clarify the factors related to the exacerbation or relief of pain;

　　2. Depression:Pain is caused or exacerbated by sexual intercourse, but it does not affect sexual life. The patient has significant depressive symptoms, such as loss of appetite, fatigue, insomnia, loss of libido, or lack of interest in anything, or impulsiveness, poor self-control, or sometimes anger towards the doctor. Some patients somatize all emotions or deny repression, showing indifferent satisfaction;

　　3. Abnormal disease behavior:They have a somatic bias, firmly believing that they are suffering from a disease, showing no response to the doctor's assurance, persisting in their pain symptoms. Although they seek treatment and the doctor tries his best to treat them, they always have pain.

　　Second, physical examination

　　1. Psychological and spiritual examination

　　It is often accompanied by neurotic-like symptoms, giving the doctor the impression that the patient is exhausted, depressed or anxious, tense, irritable, and although the pain is unbearable, no positive signs can be found during the examination.

　　Psychological investigation is a comprehensive and accurate evaluation of the condition, and serves as the basis for evaluating the progression of the disease or the efficacy of treatment measures in the future. The patient should be informed of this meaning to obtain full cooperation.

　　2. Physical examination

　　While guiding the patient to relax the abdominal, thigh, and vaginal orifice muscles to alleviate discomfort during the examination, the extent of the patient's control over muscle tension can be understood. Palpation of the levator ani and piriformis muscles during rectal examination causes pain, indicating pelvic floor muscle tension and pain. Discomfort is usually manifested as a sense of pressure in the pelvis and radiating pain towards the sacrum, close to the attachment points of the levator ani. This condition is often the result of certain pelvic pain, but it can also be a disease in itself.

　　Bimanual and trichosalpal examinations:

　　Attention should be paid to whether there is thickening in the adnexal area, how active it is, and whether there is pelvic floor relaxation, coccygeal tenderness, and lesions that may cause dyspareunia. Gentle palpation may detect sensitive areas that correspond to vestibulitis of the vaginal orifice or trigger points at a higher vaginal location. Gently palpating the abdominal wall with the fingertips can discover trigger points in the muscle tissue.

　　Pelvic examination sometimes requires combination with local nerve block to eliminate interference and facilitate differential diagnosis. For example, local anesthetic can be injected into the tender points of the abdominal or pelvic wall to relieve local muscle pain before repeating the pelvic examination. The doctor can then distinguish between true organ pain and surrounding muscle pain. For instance, after blocking the sacral nerve through the vagina, if the tenderness during pelvic examination is relieved or disappears, it is estimated that the pain originates from the uterus; if the pain does not subside, it is difficult to distinguish the possibility of block failure, except for pain not originating from the uterus.

　　3. Pelvic examination

　　No positive findings, but the pelvis is overly sensitive, even slight palpation can cause severe pain.

　　History-taking and physical examination should be conducted carefully, comprehensively, and systematically to carry out necessary auxiliary examinations and find organic diseases. The development of modern medical technology has provided a variety of diagnostic and therapeutic tools for clinical doctors, but sometimes it is still difficult to diagnose complex lesions such as CPP. When there is no obvious organic cause of pelvic pain, doctors should not easily diagnose psychological pelvic pain and should discuss with psychiatrists for reasonable analysis and judgment, and make the final diagnosis. It is also necessary to pay attention to avoid repeated or unnecessary examinations or diagnostic tests.

　　Active treatment of chronic pelvic disease and active psychological treatment should be carried out. In the treatment, attention should be paid to involving the husband of the woman or other family members in the appropriate occasion to increase the support of the family members for the treatment and achieve the expected efficacy.

　　It must be noted that for patients with negative physical examination and psychological tests, observation should be stopped immediately to avoid unnecessary new psychological problems caused by long-term observation.

　　1. Imaging examination

　　1. Ultrasound:As the most commonly used non-invasive imaging detection method in gynecology, ultrasound can detect abnormal anatomy in the pelvis, distinguish the nature of masses (cystic or solid), and can also identify vascular characteristics through color Doppler. However, it does not always provide etiological information of CPP. Whether it is abdominal or vaginal ultrasound, it can preliminarily exclude organic lesions in the pelvis, which is beneficial to alleviate the patient's psychological concerns. Combined with detailed medical history and comprehensive physical examination, ultrasound is not necessarily an essential examination item. However, for patients with tense abdominal walls, unable to cooperate, or unwilling to undergo pelvic examination, it has important diagnostic significance. In recent years, the development of multi-dimensional ultrasound technology will surely open up broader application prospects for it.

　　2. X-ray:Including intravenous pyelography, barium enema, upper gastrointestinal tract radiography, abdominal flat film, and pelvic imaging, mainly for common non-gynecological conditions causing CPP, such as urinary tract stones, intestinal lesions, and skeletal lesions, and selectively applied with the purpose of targeting.

　　3. CT and MPI:It is a more sensitive but also more expensive examination item. Before selection, the doctor should clarify whether there is a clear suspicion tendency and whether such an examination is needed to confirm it, such as: (1) suspected malignant tumor; (2) suspected retroperitoneal lesions; (3)可疑的直肠阴道隔或阴道穹隆部的子宫内膜异位灶等, it is not appropriate to use the above two examinations to confirm the positive signs found by physical examination.

　　2. Endoscopic examination

　　1. Cystoscopy:When considering symptoms originating from the lower urinary tract, in the case of excluding infection, cystoscopy is necessary. General cystoscopy can be performed in the outpatient department. However, if pain is accompanied by frequent urination, dysuria, and symptoms worsen when the bladder is full, interstitial cystitis should be suspected. In this case, hospitalization and full assessment under anesthesia are required. In the case of interstitial cystitis with a full bladder, characteristic petechiae on the bladder wall can be seen, and this process is difficult to tolerate for patients without anesthesia.

　　2. Colonoscopy:Symptoms originating from the intestines are not uncommon in CPP. Alternating diarrhea and constipation are very likely to be irritable bowel syndrome, but if the patient is mainly suffering from diarrhea and blood and mucus are present in the stool, it is necessary to check for any colonic mucosal lesions. Colonoscopy is the most accurate examination method for the lower gastrointestinal tract, and it can clearly display intestinal mucosa and submucosal lesions, but it still needs to emphasize the importance of specific indications.

　　Third, Laparoscopy

　　Laparoscopy, as a minimally invasive direct visualization diagnostic tool, is considered an indispensable important means for gynecologists to assess CPP. According to statistics, more than 40% of laparoscopic examinations are used for the assessment of CPP. Laparoscopy can obtain clear images of the surface of the pelvic and abdominal organs and can also collect lesion tissue samples for pathological examination, thus enabling the detection of pathological conditions that physical examination and imaging examination cannot find. It is noteworthy that laparoscopy can only confirm the cause of 60% of CPP. Even if a certain lesion is found by laparoscopy, it is mostly a partial cause of CPP. Therefore, before deciding to perform a laparoscopic examination, all possible causes of pain should be listed based on an initial assessment from medical history, physical examination, and other auxiliary diagnostic results. Only when the results of the laparoscopic examination are expected to change the treatment of the patient should surgery be performed.

　　In recent years, the development of new small-diameter fiber endoscopes has enabled diagnostic laparoscopy to be widely carried out in outpatients. The slender 'needle-type' endoscope has more perfect optical properties and causes less trauma when entering the abdominal cavity. This laparoscopic examination performed under local anesthesia also has unique advantages. Since the patient is conscious during surgery, they can cooperate with the surgeon to find painful lesions. For example, if pulling on adhesions causes the patient's habitual pain, further adhesion dissection is reasonable.

　　The common findings under the CPP microscope are as follows:

　　1. Endometriosis (EM):Typical EM lesions may not be difficult to identify, but CPP patients often have atypical EM. Various subtle non-pigmented lesions require close observation (within 1-2 cm of the lens) and multi-angle observation to be detected. Sometimes, a peritoneal biopsy is necessary to find them. EM lesions often hide beneath scar tissue, and one should be vigilant for signs of adhesions, scars, and anatomical deformities. With the help of instruments and vaginal-rectal three-part examination during surgery, as well as patient cooperation, careful palpation may maximize the possibility of not missing any diagnosis.

　　2. Adhesions:Not all adhesions found during surgery are the culprit causing CPP. Generally speaking, membranous adhesions are unrelated to CPP, while dense adhesions that cause anatomical distortion and organ function damage are very likely to be the cause of pain. The interconfirmation between the pain localization map drawn before surgery and what is seen during surgery is helpful for differential diagnosis.

　　3. Hernia inguinal hernia:Under laparoscopy, it appears as a peritoneal hernia opening on the round ligament side, an indirect hernia can sometimes be found in the blind triangle of Hesselbach, if not clear, the peritoneum in the Hesselbach triangle area can be pulled towards the head side, and pleats or hernia sacs can be found, the exposure of inguinal hernia under laparoscopy is relatively complex.

　　4. Pelvic congestion syndrome:Laparoscopy is not the most reliable method for diagnosing pelvic varicose veins. Due to increased venous return in the Trendelenburg position, varicose veins may disappear. Transvaginal ultrasound and transcervical venography are minimally invasive and more accurate methods, and it is best to complete them before laparoscopy.

　　5. Other:Some conditions are often seen in the laparoscopic examination of CPP, but they are rarely the cause of CPP, such as functional ovarian cysts, Morgagni cysts, peritoneal window (Allen-Masters syndrome), etc. They divert the surgeon's attention and ignore the effort to continue searching for the true cause of pain.

　　One, chronic pelvic pain food therapy recipe

　　1. Lychee kernel honey drink

　　Composition: Lychee kernel 30 grams, honey 20 grams.

　　Usage: Crush the lychee kernel and put it into the pot, add water and soak for a moment, then boil for 30 minutes, remove the residue and take the juice. Mix it with honey while warm, stir evenly, and it's ready. Take it twice a day in the morning and evening.

　　Effect: Regulate Qi, promote diuresis, and relieve pain.

　　2. Green peel and safflower tea

　　Composition: Green peel 10 grams, safflower 10 grams.

　　Usage: Dry the green peel and cut it into strips, then add it to the pot with safflower along with water, soak for 30 minutes, then boil for 30 minutes. Filter it with clean gauze, remove the residue, and the juice is ready. Drink it frequently as tea, or take it twice a day in the morning and evening.

　　Effect: Regulate Qi and activate blood circulation.

　　3. Peach kernel cake

　　Composition: Peach kernel 20 grams, flour 200 grams, sesame oil 30 grams.

　　Usage: Grind peach kernel into a very fine powder and mix it thoroughly with flour. Add 1000 ml of boiling water, knead thoroughly after cooling, roll out into a rectangular thin skin, spread sesame oil on it, roll it into a cylinder shape, cut it with a knife into sections of 30 grams each, roll it into a round cake, and bake it in a flat pan. Take it at will for breakfast and dinner, several times a day, two pieces each time, with warm water.

　　Effect: Regulate Qi and activate blood circulation, resolve blood stasis and relieve pain.

　　Two, what foods are good for chronic pelvic pain

　　1. Consume light, easy-to-digest foods such as red beans, mung beans, loofah, lentils, and purslane. Foods with the function of promoting blood circulation and resolving blood stasis should be consumed, such as hawthorn, peach kernel, fruit candy, tangerine kernel, tangerine peel, rose, and tangerine.

　　2. Appropriately supplement proteins, such as lean pork, ducks, geese, and quails.

　　3. Pain relief can be achieved by eating cuttlefish, red prawns, lobsters, scallops, tiger fish, beets, mung beans, radishes, chicken blood, etc.

　　Three, it is best not to eat those foods with chronic pelvic pain.

　　1. Abstain from cold and raw foods such as cold drinks and fruits.

　　2. Avoid spicy, warm, and stimulating foods such as chili, lamb, dog meat, roosters, etc.

　　3. It is not advisable to eat fatty, cold, sticky foods. Such as fatty meat, crab,螺蛳, preserved meat products, etc.

　　4. Abstain from smoking and drinking.

　　1. Treatment

　　Although the etiology of chronic pelvic pain has not been elucidated, the basic view at present is that CPP is a complex disease involving somatic and psychological factors. Even if there are obvious somatic lesions that can cause pelvic pain, the influence of psychological and social factors on the disease cannot be ignored. Treatment requires the use of comprehensive methods from multiple disciplines, including surgery, medication, physical therapy, psychological treatment, dietary therapy, etc. The goal of treatment is to relieve pain, improve function, and eliminate psychological barriers, but the treatment effect is not good for those with a long course of disease.

　　1. General principles:Firstly, it is necessary to find out as many pathogenic factors as possible. The most effective clinical method requires treating all possible factors at the same time: anatomical, musculoskeletal, intestinal and bladder functional, psychological issues, etc. Treatment usually starts with multiple medications together, although they can usually well relieve pain, but it is inevitable to worry about it. By regular and planned careful follow-up, the dosage of drugs can be gradually reduced, and patients' conditions and needs can be timely understood.

　　The treatment process of CPP is not only difficult to achieve the initial intention of patients to quickly resolve the problem with simple methods, but also inevitable to produce a sense of defeat in the treating doctors. In fact, both patients and doctors must cooperate for a long time, be prepared to fight a protracted war, and completely change the traditional understanding of treatment success. Whether the treatment of CPP is successful or effective is not necessarily to relieve pain completely; as long as the pain does not worsen or gradually decrease; or pathological changes do not worsen or gradually decrease; or although the pain remains, the mental state or work and life ability or marital relationship and sexual life adjustment ability improves; or can be free from surgery for a long time; or even if they can persist in taking medication and actively cooperate with treatment, these are all standards of success. Doctors need to adjust their mindset and continue to support and help patients as always.

　　2. Patient education:To enable patients to understand and accept the doctor's treatment plan, it is necessary to explain to them some knowledge about pain and the significance of various examinations. Patients should know that the doctor has made the diagnosis after careful examination and scientific argumentation. Only by gaining the complete trust of patients can they fully express their inner feelings and hidden conflicts, and accept the doctor and their treatment plan from a psychological perspective. By listing common pathogenic factors, the doctor should analyze the patient's condition together with the patient and formulate an ideal and economic treatment plan.

　　In contact with patients and their families, it is necessary to fully explain the close relationship between emotional suppression and CPP, so that patients understand the different levels of individual disease cognition, which can cause significant differences in the perception of their own pain. In addition, do not ignore the harmful effects of CPP on the family and the great help of family roles in overcoming pain. It is recommended that family members help patients arrange their daily lives reasonably, gradually restore their family status, and in many cases, this change can greatly enhance the confidence and courage of patients themselves.

　　Some CPP patients seek medical attention due to sexual dysfunction and often place their hopes on medication. However, the most practical method is to help them improve by reducing conflict, increasing sexual stimulation, and changing sexual positions.

　　3. Drug treatment:The principle of using as few or no drugs as possible does not apply to CPP. Single drug use is often difficult to achieve ideal results. Once the patient loses confidence for this reason, it adds difficulty to the subsequent combined drug use. The combined use of drugs for CPP should pay special attention to drug interactions, frequently check the reactions of drugs, try to reduce the types and dosages of drugs, in order to reduce side effects and costs.

　　The commonly used drugs are introduced as follows:

　　(1) Analgesics: Including non-steroidal anti-inflammatory drugs (NSAIDs), composite agents of NSAIDs and milder anesthetics, and pure anesthetics. NSAIDs have side effects such as gastric mucosal damage and renal damage, while the addiction potential of anesthetics is more concerning. However, when tolerance is good, all three types of drugs can achieve good efficacy for appropriate patients (those who can control medication自觉, without a history of drug abuse).

　　(2) Antidepressants: About half of chronic pain patients are accompanied by depression. Antidepressants not only counteract depressive mood but also have an unknown mechanism of analgesic effect. The efficacy of antidepressants for chronic pain is not very reliable, but due to their advantages of being a substitute for anesthetics, not easily abused, and low dependence, they are widely used.

　　Tricyclic antidepressants have been used to treat chronic pain for decades. Amitriptyline is a representative drug, and a large number of clinical practices have confirmed its efficacy. The dosage is 50-75mg/d, accounting for only 1/3 to 1/2 of the conventional treatment dose for depression. The most common side effects are constipation and morning drowsiness. For patients with irritable bowel syndrome or significant bladder hypersensitivity, the anticholinergic side effects can have a beneficial effect.

　　Selective serotonin reuptake inhibitors (SSRIs) are a new type of antidepressant with higher efficacy than tricyclics and fewer constipation side effects. Due to the effect of overexciting smooth muscle, it can cause slight diarrhea and intestinal cramps. Currently, SSRIs in clinical application include fluoxetine, paroxetine, and sertraline, etc.

　　(3) Organ-specific drugs: During the treatment of CPP, for gastrointestinal symptoms, bladder irritation symptoms, and skeletal muscle pain, etc., it is also necessary to be familiar with the use of antispasmodics, muscle relaxants, and other medications. However, it is also possible to consult with a specialist doctor for guidance on medication. For patients with sexual dysfunction, guidance on the use of vaginal lubricants and other external methods is also needed.

　　(4) Other medications: Medroxyprogesterone acetate (Anagestrel) can reduce pelvic congestion by inhibiting ovarian function, thereby alleviating related pain. GnRH-a has been recommended for distinguishing between gynecological and non-gynecological causes of pain. It is noteworthy that it also has a relieving effect on irritable bowel syndrome, which may be due to the reduction of serum relaxin.

　　4. Surgical methods:There are roughly three basic surgical methods used to treat CPP: (1) Removal of visible lesions, restoration of anatomy, especially laparoscopic surgery; (2) Removal of pelvic organs; (3) Nerve ablation. The general situation is that there is a lack of widespread and standardized research on various surgical methods, and clinical doctors need to be cautious in accepting related conclusions.

　　Conservative laparoscopic surgery, represented by the treatment of endometriosis (EM), can include procedures such as oophorectomy, adhesion lysis, and lesion resection or cauterization under the condition of preserving fertility. Prospective studies have shown that two-thirds of patients can obtain long-term relief as a result, but the issue of long-term recurrence should not be overlooked.

　　Some studies have shown that on the basis of conservative surgery, concurrent sacral nerve resection (PSN) can significantly alleviate dysmenorrhea and sexual pain in 75% to 95% of patients, which is significantly better than conservative surgery alone (25%). However, some study results are not optimistic. PSN requires high technical requirements of the operator and has complications such as constipation (37%) and urgency (8%). Its main indication is intractable pelvic middle pain that is resistant to systemic internal medical treatment, and chronic pain from the lateral side of the pelvis or other tissues is difficult to alleviate. Therefore, it is necessary to conduct a thorough preoperative evaluation, skill preparation, and patient communication before considering this procedure.

　　LUNA is a laparoscopic sacral nerve resection, and it is mainly applicable to pain originating from the middle of the pelvis. It is generally believed that this procedure has a low relief rate for pelvic pain (33%), with a postoperative recurrence rate greater than 50%. Compared with PSN randomized controlled trials, its efficacy is significantly lower than that of the latter (pain relief rate of 82%). The surgical operation of LUNA is relatively simple, but there are also risks of injury to the uterus, blood vessels, and ureters. In addition, complications such as uterine prolapse and postoperative urinary retention are not uncommon, so it is not the preferred surgical procedure for treating CPP.

　　In terms of treating adhesive lesions, laparoscopic surgery is more effective than open surgery. Although confirmation from secondary exploration is lacking, several clinical studies that have used treatment of pelvic adhesions to alleviate pain have been encouraging, with a pain relief rate of 65% to 84%.

　　In the United States, cesarean pain purpura (CPP) is also a common indication for hysterectomy (accounting for 18%), first, hysterectomy is significantly more effective than medication in alleviating the symptoms of CPP (relief rate of 78% to 95%), but approximately 22% of patients continue to experience pain for one year after surgery. This situation is more likely to occur in patients under the age of 30, or without clear pelvic lesions, or lacking social and interpersonal support, or with a history of pelvic inflammatory disease. Common causes of persistent pain after hysterectomy include the retention of ovaries (whether or not varicose veins are present), residual ovaries, hernias, adhesions, and the presence of trigger points in the abdominal wall or vaginal fornix. Some of these factors are present before surgery, while others are caused by surgery. In summary, hysterectomy remains one of the important alternative treatment options for CPP, but it should be considered after thorough conservative treatment has failed and after a comprehensive and detailed evaluation. At the same time, issues such as urinary system, gastrointestinal system, musculoskeletal system, and psychological factors should be excluded.

　　For patients with persistent CPP despite the retention of ovaries and reasonable attempts, after trying all medications, it is not possible to achieve physiological menopause in the short term, the ovaries should be removed, and GnRH-α can be used before surgery to help with differential diagnosis.

　　The above discussions focus on surgical treatment for CPP in the field of gynecology. Other surgical treatments include nerve block techniques, nerve stimulation, and percutaneous nerve ablation (radiofrequency or cryotherapy) and other techniques.

　　6. Psychological treatment of CPP:CPP is the result of the combined action of physical, psychological, and social factors, therefore, a pelvic pain treatment team composed of professionals from multiple disciplines can be established. This team should include obstetricians and gynecologists, psychologists, nurses, etc., to evaluate various factors and formulate appropriate treatment plans.

　　For the first-time patients, it is necessary to eliminate their fear psychology, establish a mutual trust relationship with the patient, and then conduct a comprehensive and detailed physical examination and psychological-sociological assessment to determine whether the patient has organic etiology. The psychological-sociological assessment includes a complete medical history of physical and mental diseases, especially sexual history, the patient's understanding of the disease, and necessary psychological-behavioral scale measurements to understand the patient's personality and emotions, find the psychological reasons for CPP. For patients without obvious organic lesions but with psychological disorders, psychological treatment should be performed, which can start with simple methods, such as education and elimination of doubts, and gradually proceed to special psychological treatment techniques such as relaxation therapy, cognitive therapy, support therapy, hypnosis, etc.

　　Cognitive therapy mainly focuses on the subjective cognitive problems of patients. By changing the patients' views and attitudes towards themselves, others, or things, the psychological problems that arise can be improved. The implementation of cognitive therapy first requires the therapist to explain to the patient why one's views and attitudes can affect their mood and behavior, followed by helping the patient to examine the views and attitudes they hold towards themselves, others, or the surrounding environment, assisting the patient in discovering the gap between these views and attitudes and general reality, pointing out their pathogenic nature, and then urging the patient to practice changing these views and attitudes, establishing more objective and healthy views and attitudes, and using these new views and attitudes to produce healthy moods and adaptive behaviors. At the same time, techniques such as self-confidence training, role-playing, and cognitive rehearsal can be used to assist cognitive therapy. Cognitive therapy is applicable in clinical practice for patients with CPP caused by depression.

　　Relaxation therapy is more suitable for dealing with tension, anxiety, unease, and anger. It can help patients recover their spirits, restore their strength, eliminate fatigue, stabilize their emotions, including muscle relaxation training, imaginative relaxation, and deep breathing relaxation methods.

　　During the treatment process, it is recommended to allow the husband of the woman or other family members to participate in the treatment at appropriate times to increase the support of family members for the treatment. It is noteworthy that patients with negative physical examinations and psychological tests should stop observation immediately to avoid long-term, fruitless observation causing unnecessary psychological problems for patients.

　　6. Other therapies:Physical therapy is a relatively effective pain relief method, among which transcutaneous electrical nerve stimulation (TENS) and biofeedback methods have significant efficacy. TENS is suitable for diffused, uncertain somatic pain. Transvaginal TENS may produce beneficial stimulation on pelvic muscle tissue and internal organs, resulting in encouraging analgesic effects. Biofeedback therapy is effective for headaches, but there is a lack of data on its direct effect on CPP. However, the establishment of a mutual trust between doctors and patients during biofeedback treatment is often more meaningful than the treatment itself.

　　Massage can often produce a good therapeutic effect for patients with combined skeletal and muscle diseases. Some people use vaginal massage to relieve CPP to some extent.

　　Traditional Chinese medicine acupuncture therapy also has a certain analgesic effect, but the efficacy of Chinese medicine for CPP varies greatly from person to person. In addition, Chinese herbal medicine, osteopathy, acupressure therapy, and yoga also have successful treatment experiences.

　　In addition, reasonable physical exercise can stimulate the release of endorphins and relax the body and mind. Physical exercise should be placed on an equal footing with medication. At the same time, it is also necessary to discuss with patients the impact of diet, lifestyle, and personal habits on health, guide them to have a reasonable diet, scientific exercise, and rest.

　　7. Laparoscopic treatment

　　The laparoscopic surgical treatment for chronic pelvic pain should be determined according to its specific situation. Common surgical methods include:

　　(1) Adhesion relaxation: Laparoscopic adhesion relaxation is an effective method for treating chronic pelvic pain. It can separate adhesions under direct vision using methods such as electrocoagulation, electrosection, laser, and argon, etc. The vast majority of adhesions can be successfully separated. However, there is still controversy about the therapeutic effect of this surgery. According to Steege's report, the relief of pelvic pain after the separation of mild to moderate adhesions is not significant, but the pain relief after the separation of severe adhesions, especially intestinal adhesions, is significant. Schietroma reported that after 41 cases of pelvic adhesion relaxation surgery, 59.4% (22 cases) of abdominal pain disappeared, 24.3% (9 cases) showed significant relief, and 16.2% (6 cases) had no improvement in symptoms, indicating that laparoscopic adhesion relaxation surgery can make more than 80% of chronic pelvic pain symptoms disappear or alleviate.

　　When separating adhesions with laparoscopy, attention should be paid to:

　　The abdominal wall puncture point should be avoided as much as possible from the suspected adhesion site. For patients with a history of multiple surgeries or suspected extensive adhesions, open laparoscopic examination and surgery can be performed.

　　When separating adhesions around the intestinal tract, it is best to use sharp dissection methods rather than electrical or laser methods.

　　Special types of adhesions, such as filmy or jelly-like adhesions, can be separated using the water stripping method.

　　When separating dense adhesions, attention must be paid to the surrounding anatomical relationships, the course of blood vessels and important organs, variations, etc., and it is best to separate them layer by layer to avoid injury and bleeding.

　　After extensive peritoneal and pelvic adhesion separation surgery, preventive measures against re-adhesion should be taken, such as the placement of low molecular weight dextran or biological protein glue, hyaluronidase, and others.

　　(2) Endometriosis surgery: Pelvic endometriosis is a common cause of CPP, with lesions often located in the ovary, uterine rectal pouch, uterosacral ligament, posterior leaf of the broad ligament, and other areas. The lesions can be seen as typical blue-black, brown-black, brown, red spots or plaques, or the formation of chocolate cysts in the ovary under laparoscopy. Sometimes, the lesions may be atypical membranous or fluffy adhesions. They can usually be diagnosed by the naked eye, and biopsies are needed for suspected cases for histological diagnosis.

　　The treatment method of pelvic endometriosis by laparoscopy depends on the location and size of the lesion. For ovarian endometriosis with lesions less than 5mm, biopsy, coagulation, and vaporization can be performed; for lesions between 5mm and 2cm, vaporization or resection can be chosen; for lesions with a volume of 2 to 5cm, the ovary should be incised, drained, and the inner wall checked to determine the pseudocapsule, then the wall of the cyst is peeled off from within the ovary; when the diameter of the ovarian chocolate cyst exceeds 5cm, according to the patient's age, the condition of the contralateral adnexa, and other factors, cystectomy or unilateral adnexectomy can be performed.

　　For peritoneal endometriosis with a small volume (maximum diameter ≤ 2mm), various treatment methods can be used, but it is necessary to take a biopsy first for those with unclear diagnosis. For larger lesions, vaporization or resection can be helpful, but it is best to perform a more thorough resection for endometriosis that invades the bladder or intestines with a diameter greater than 5mm. If the volume of the lesion is large or the invasion is deep, it is necessary to seek the assistance of a surgeon. Lesions in these areas may appear small on the surface, but most of them protrude into the cavity. For deep infiltrative lesions in the uterine rectal pouch, extra caution must be exercised during treatment. The boundaries of lesions under the microscope are often unclear, especially the depth of invasion in the rectal muscle layer is difficult to discern. Inexperienced doctors are prone to cause intestinal perforation or delayed intestinal perforation, and it is best to handle this situation with a surgeon.

　　Emmertc et al. reported that the detection rate of laparoscopic endometriosis was 35.2% (37/105), with the lesions localized in the uterine rectal pouch accounting for 64.8%, invasion of the uterosacral ligament in 37.8%, involvement of the ovary in 24.3%, and only 42.8% of the lesions were positive on biopsy. In 91.9% of the cases, symptoms were relieved or partially relieved after laparoscopic surgery.

　　(3) Sacral colpoperineal nerve resection, preperitoneal nerve resection: Sacral colpoperineal nerve resection is an easy operation, during which the uterus is pushed forward towards the anterior abdominal wall using a uterine manipulator. The entire course of the uterine sacral ligament and ureter in the pelvis is identified, and the inner side of the ligament at the junction with the uterus is cauterized with a laser until it is completely or partially cut. The vaporization range of the ligament is generally 1.5 to 2.0 cm in depth and 1.0 cm deep. At the same time, a superficial 'U'-shaped vaporization area is made at the back of the junction between the uterine rectal pouch, which can cut off the nerve fibers that are connected to each other, otherwise they may be missed. The success rate of sacral colpoperineal nerve resection in alleviating primary dysmenorrhea is 49% to 70% after one year of follow-up, and the rate of secondary dysmenorrhea caused by endometriosis is about 71%.

　　Laparoscopic presacral neurectomy is commonly used for severe dysmenorrhea or chronic pain related to endometriosis. This surgery requires certain skills and can only be performed by those who are very familiar with retroperitoneal anatomy. During the operation, excellent and meticulous stripping is required, and the resection margin is the same as that of laparotomy: above, from the bifurcation of the aorta; on the right, the right internal iliac artery and the right ureter; on the left, the inferior mesenteric artery and the superior hemorrhoidal artery; below, just below the inferior lumbar splanchnic plexus; depth to the periosteum of the coccyx. This area is where the presacral nerves are located. The presacral nerves are actually part of the superior splanchnic plexus, one of the 23 sympathetic ganglion plexuses, transmitting stimuli to the organs. The upper part is retroperitoneal, extending from the bifurcation of the aorta to the junction of the fifth lumbar and first sacral vertebrae, where it forms the middle inferior splanchnic plexus. Most of the sensory nerve fibers of the uterus and cervix pass through this plexus.

　　Chen et al. performed laparoscopic presacral neurectomy in 655 patients with CPP, and the symptoms of 62% of the patients were significantly relieved after surgery. Carrcia compared the efficacy of laparoscopic uterine sacral nerve ligation and presacral neurectomy, and the latter showed significantly better efficacy than the former, considering presacral neurectomy as a safe and effective method for treating chronic pelvic pain.

　　(4) Laparoscopic hysterectomy: Although there are many methods to treat CPP, still 10% to 12% of patients may ultimately need to undergo hysterectomy. For patients with refractory and difficult-to-treat diseases, hysterectomy with bilateral adnexectomy can still improve symptoms in 77.8% of patients, most of whom suffer from adenomyosis or pelvic congestion syndrome.

　　Laparoscopic hysterectomy has become a routine surgical procedure, with relatively simple technical requirements. According to the specific conditions of the patient, laparoscopic total hysterectomy (LTH), laparoscopic assisted vaginal hysterectomy (LAVH), laparoscopic intraperitoneal hysterectomy (LIH), and laparoscopic subtotal hysterectomy (LSH) can be performed.

　　II. Prognosis

　　Chronic pelvic pain is such a perplexing and challenging complex disease that it requires confidence, patience, and perseverance to face it. In the process of overcoming pain and suffering, multidisciplinary cooperation between gynecologists, surgeons, internists, rehabilitation physicians, and psychiatrists is needed to work tirelessly with patients.