Pelvic stasis syndrome PCS, also known as ovarian venous insufficiency or ovarian venous syndrome, is a specific syndrome with chronic pelvic pain CPP as the main clinical manifestation due to chronic stasis in the pelvic veins, and most patients with PCS have ovarian varicose veins. However, due to the diversity and non-specificity of clinical symptoms of PCS and the lack of objective examination indicators, most of the CPP caused by PCS has not been correctly diagnosed so far.
Etiology of PCS.
The etiology of PCS is complex and the current mechanism is unclear, and most believe that it is the result of a combination of multiple factors.
1. Anatomical and physiological factors.
The pelvic venous reflux system has abundant traffic branches. The ovarian veins are connected to the fallopian tubes and uterine veins through the broad ligament and to the rectal and bladder veins. The left ovarian vein flows back into the left renal vein at right angles, and its venous valve defect rate is 15%, much higher than the 6% on the right side, so the left ovarian vein is prone to reflux. The average diameter of the ovarian vein was found to be 2.6-3.6 mm by imaging and autopsy.
Retroperitoneal vein variation may be another cause of PCS. Normally, the left ovarian vein returns to the inferior vena cava through the renal vein at a pressure of, and in cases of left renal vein hypertension up to 4 mm Hg. The most common variant is Nutcracker syndrome, where 20% of patients with ovarian vein regurgitation have a similar anatomic variant, presenting early with left renal vein hypertension but normal ovarian vein valve function; late with valve insufficiency, leading to PCS. followed by left renal vein variant, especially in women with posterior aortic renal veins who develop ovarian vein regurgitation at a significantly higher rate. Among these, the diameter of the left renal vein was positively correlated with the incidence of left ovarian varices as well as the rate of left ovarian venous regurgitation. In addition, venous hypertension spermatozoa such as portal hypertension and acquired inferior vena cava syndrome can also lead to PCS.
Abnormal uterine position, such as posterior tilt and posterior curvature of the uterus, can lead to venous distortion and stagnation and reflux of blood flow; heavy physical labor and long-term standing can lead to poor pelvic venous reflux, thus aggravating ovarian varicose veins; pelvic surgery, such as tubal ligation, can lead to bruising and PCS by damaging the tethered vessels during surgery and affecting utero-ovarian venous reflux.
2. Endocrine and other factors.
PCS occurs only in women of reproductive age, and inhibition of ovarian function may improve symptoms, suggesting that the disease is related to hormone levels. Since no difference was found in the sex hormone levels in peripheral blood between PCS patients and normal women, it is thought that it may be due to disorders in local ovarian hormone levels. Ovarian hormones can inhibit peripheral vasoconstriction against venous pressure and downregulate increased venous pressure by decreasing peripheral blood flow in normal women during the follicular phase; during the luteal phase this stress response is variable and increased blood flow is often seen by Doppler ultrasonography.
Some PCS patients have a familial predisposition and most are particularly sensitive to environmental stress. The pelvic organs consist of richly divided smooth muscle and a large number of blood vessels, and pelvic venous blood flow can change rapidly in response to pressure changes, while the pelvic venous plexus lacks supporting structures, leading to congestion and stasis. Although the emotional psychological scores of patients with CPP due to PCS show anxiety and depression, psychotherapy does not reduce the diameter of dilated veins and improve symptoms. Therefore, it is currently believed that PCS is not a psychogenic disease and that its associated clinical symptoms are a subsequent response to CPP caused by PCS.
Diagnosis of PCS
I. Clinical manifestations.
The relatively characteristic symptoms are “three pains, two more, and one less”, namely: lower abdominal pain, low back pain, and deep intercourse pain; more menstrual volume and vaginal discharge; and less positive signs. Abdominal pain and low back pain are mostly seen in young menstruating women. The lower abdominal pain is variable in intensity and duration, sometimes extending to the thighs and buttocks or manifesting as post-sacral pain, aggravated by increased pelvic vein congestion before or during menstruation, fatigue, and uprightness, and relieved by lying down and elevating the thighs. The pain can be acute or manifested as chronic dull pain, mostly accompanied by heaviness in both lower extremities, which can lead to sudden trigger pain due to postural position changes such as bending over.
II. Auxiliary examinations.
1. Non-invasive examinations.
(1) Transabdominal or transvaginal color Doppler ultrasonography: characterized by: pelvic circumferential or linear, dilated veins more than 5 mm in diameter, Doppler ultrasound showing multiple dilated venous echoes around the ovaries and uterus; slow blood flow (3 cm/s) or with terminal reflux; dilated myometrial arch veins connecting the bilateral pelvic varices. Improvement in the degree of varicose veins and variable double flow peaks, as well as uterine enlargement, endometrial thickening and ovarian polycystic-like changes can be observed on Doppler ultrasound by the Valsalva method.
(2) CT or MRI: Both CT and MRI show pelvic venous tortuosity with increased dilated and distorted tubular vascular structures in the ovaries, periuterine, broad ligament and paravaginal area. Simultaneous visualization of the ovarian and renal veins may suggest renal vein reflux. Because MRI can visualize vessels at the same circulation time using 3D imaging techniques, whereas CT must scan the upper and lower layers separately at different times, MRI vein visualization has become the preferred noninvasive examination for PCS in recent years. However, all of these examinations require the supine position, thus leaving the tortuous pelvic veins in relative remission in the postural position and therefore masking mild varicosities. It has been reported that for PCS, the sensitivity of MRI, CT and ultrasonography is 58.612.5% and 20%, respectively.
2. Invasive examinations.
It mainly refers to venography and laparoscopy via vulvar, uterine or femoral vein puncture.
(1) Venography: the pelvic vein scoring system of PCS is: when the diameter of ovarian vein is 1-4, 5-8, >8mm, the contrast dwell time is 0, 20, 40s respectively, pelvic vein stasis and/or ipsilateral or contralateral internal iliac vein mild, moderate or severe stasis is rated 1-3 points respectively, and the score ≥5 points is diagnosed as PCS. where 6mm diameter of ovarian vein is used as the cutting value, the positive predictive value of up to 83.3%. Currently, pelvic venography in the upright or oblique position or selective ovarian venography is considered the “gold standard” for the diagnosis of PCS. Therefore, even if several tests are negative, as long as the clinical picture is supportive, imaging should be performed to confirm the diagnosis. It is also possible to observe the presence of reflux, contralateral venous imaging, and venous dilatation in the groin, vulva, rectum, and lower extremities.
(2) Laparoscopy: The sensitivity of laparoscopy in diagnosing PCS is 40%, and pelvic veins are seen to be tortuous, thickened or in clusters. It has been reported in the literature that the positive rate of laparoscopic diagnosis of PCS can be improved by reducing intra-abdominal pressure and using Trendelenburg position.
Differential diagnosis of PCS
PCS needs to be differentiated from chronic pelvic inflammatory disease, endometriosis and polycystic ovary syndrome.
PCS has no inflammatory signs and history of acute attacks of chronic pelvic inflammatory disease, no secondary, progressive dysmenorrhea, no small uterus, thin endometrium, abnormal menstruation, amenorrhea, hirsutism and other endocrine abnormalities, and generally does not affect conception. In addition to the more specific ovarian tenderness, there are no pelvic floor tenderness nodules and other positive signs on gynecological examination, and anti-inflammatory treatment is ineffective and may be accompanied by varicose veins in other areas. Although 50% of PCS can have ovarian polycystic-like manifestations, the polycystic ovaries of PCOS differ in that they are mostly large follicles in clusters of 3-5 with a central distribution in a loose and edematous stroma, and the follicles are significantly larger in diameter than in patients with PCOS. It also needs to be differentiated from pelvic adhesion release, atypical dysmenorrhea, neurosis, urological disorders and gastrointestinal disorders.
IV. Treatment of PCS
(I) General treatment
Improve pelvic blood flow status through rest and postural adjustment. Appropriate physical exercise to improve the torsion of tortuous veins by increasing pelvic muscle tone and correcting uterine position, supplemented by psychotherapy.
(ii) Drug treatment
Drug treatment is short-term relief and cannot cure the disease, which can be relapsed after stopping the drug or during the course of taking the drug.
1.Drugs that inhibit ovarian function.
(1) progesterone: progesterone can inhibit ovarian function, increase vascular tone, fast onset of action, the initial treatment can significantly improve symptoms and reduce bruising, remission rate of up to 40%. However, the maintenance time is short, and there is a relapse when the drug is discontinued or during the course of taking the drug.
(2) Gonadotropin agonist: compared with MPA, it has strong vasoconstrictor force, which can improve pelvic congestion and relieve painful intercourse.
2. Drugs to improve vascular tone.
Diosmin is formed by micronization of flavonoids. 500mg of Diosmin can reduce capillary permeability, increase venous wall tension and capillary resistance, and relieve and inhibit uterine contraction. Symptoms improve significantly after 2-3 months of medication, especially for painful intercourse.
3. Other allopathic drugs.
Including non-steroidal anti-inflammatory drugs, analgesics, neuromodulatory and psychotherapeutic drugs. It has also been reported that the application of lidocaine and vasodilators for intra-sacral injection, Chinese medicine enema has some short-term effect on the relief of symptoms.