EXPERTS: Dr. Neil Khilnani • Dr. Gloria Salazar • Dr. Mark Meissner

Pelvic venous disorders (PeVD), formerly known as pelvic congestion syndrome (PCS), are a common component of many venous practices with women presenting for evaluation of chronic pelvic pain. Understanding the importance of evaluating this patient population and performing complete clinical assessments is critical for identifying the etiology and optimal management strategy. The current state of knowledge about this disease process, diagnostic criteria, imaging evaluation, and treatment strategy will be reviewed by experts in this disease entity.

Case Presentation

A 48-year-old female with a history of two prior pregnancies presents with one year of chronic pelvic pain that is six to seven out of 10 on the Visual Analog Scale. Pain is worsened by prolonged standing and menstrual cycles. The patient has both coital and post-coital pain.

Question 1

What are the critical questions to ask during the evaluation of women with chronic pelvic pain (CPP) and which symptoms are most correlated with venous origin CPP?

Khilnani: The vascular interventionalists’ role in caring for women with CPP is to identify and appropriately treat those whose symptoms, physical exam, and imaging are signaling a venous origin as their primary pain generator. This can be challenging, as several conditions can lead to pain with features that overlap with those thought to be provoked by a venous condition.

Endometriosis is a common condition, and there is an impression that this is the main differential challenge. However, as I have learned from working with expert CPP gynecologists in our Pelvic Venous Disorders Workgroup, endometriosis can be a straightforward diagnosis to make. The pain in these women is typically crampy, progressing with the menstrual period with a consistent pain-free interval after menses completion. They have deep, not superficial dyspareunia.

There is no change in their pain with the time of the day or with their position. Their pain can be improved with combined oral contraceptives (COC) and progestins. On exam, they may have focal retro cervical tenderness that reproduces their deep dyspareunia, and palpable endometrial implants but no pelvic floor, abdominal, or other musculoskeletal (MSK) tenderness. In situations where the diagnosis seems straightforward, empiric hormonal therapy is initiated and is so well tolerated that laparoscopy is not needed, although in certain situations, especially in women with a presumed diagnosis who are contemplating pregnancy, laparoscopy can be helpful.

Pelvic floor myalgia (myofascial pain or PFM) presents with symptoms that overlap greatly with venous-origin chronic pelvic pain (VO-CPP) and a good history and physical exam along with imaging is necessary to optimize the diagnosis. Like VO-CPP, PFM is better in the morning and worse at the end of the day, worse with activity and standing, and improved with lying down and heat. Both can have prolonged post-coital aching and although dyspareunia is classically entry, many PFM women complain of deep dyspareunia as well. Neither condition responds to COC. The only distinguishing historical features are that PFM may improve with NSAIDs but not ovarian suppression. In contrast, VO-CPP does not improve with NSAIDs but may be quite responsive to ovarian suppression.

A physical exam is very helpful in trying to distinguish these etiologies. VO-CPP likely will have tenderness over the ovarian point on the external exam and of the uterus, ovaries, and adnexa on a bi-manual exam and the symptoms typically reproduce the symptoms the patient is complaining of. They may have extra-pelvic varicose veins of pelvic origin as well. However, they have no pelvic floor or MSK tenderness in the absence of central sensitization. In contrast, women with PFM have no ovarian point, uterine or adnexal tenderness, but likely have a high pelvic floor tone, and palpation of portions of the pelvic floor reproduces their pain. In addition, they may have abdominal or other MSK issues.

Imaging demonstrating multiple tortuous periuterine, periovarian, perivaginal, and uterine arcuate varices is helpful in supporting a VO-CPP diagnosis, although we know that such dilated veins can be seen in asymptomatic women as well.

Partnering with a pelvic pain specialist to evaluate most if not all of the patients we see seems likely to enhance patient selection, and ultimately patient referrals from this and associated gynecologists and is something I would strongly recommend considering.

Meissner:
1. How many days a month do you have pain and how does the intensity of pain fluctuate throughout the month?
2. Is the patient post-menopausal?
3. Have you seen your gynecologist and do they have any organic explanation for the pain?
4. Do you have anxiety or depression?
5. Do you have any other chronic pain problems – e.g. fibromyalgia, hypermobile EDS, TMJ syndrome, migraines, interstitial cystitis, irritable bowel syndrome, median arcuate ligament syndrome?
6. Where is the pain localized (ovarian points, back, etc)?
7.Do you have any urinary symptoms – e.g frequency, urgency, etc.?
8. Do you have left flank pain or hematuria?
9. Do you have any leg symptoms – e.g swelling, heaviness, exertional discomfort?

There is not one ideal imaging test. In fact, one could consider that there are two imaging goals in this situation, one for screening and one for anatomical and physical evaluation, and each may have a different best strategy.

Non-cyclic pain (pain most days of the month, but worse during menstruation), dyspareunia, post-coital ache often lasting several hours, and “congestive” dysmenorrhea (although not sure that this is uniformly recognized by the gynecologic community) have been most highly associated with VO-CPP.

Salazar: In my practice, I usually inquire about the temporal relationship between the onset of symptoms and pregnancies, whether the patient has developed vulvar varices or not during that time, and finally the venous characteristic of the pain: postural chronic pelvic pain (heaviness, cramping) relieved by lying flat, with some patients needing to have a “break” in the middle of the day to relieve the pain. The three “P” s (pelvic pain, provoked by gravity, and prolonged post-coital ache) are the most frequent clinical findings in VO-CPP in women, in my experience.

Question 2

What is the ideal imaging assessment of this patient population and what tool do you utilize in most patients?

Meissner: I rely almost exclusively on transabdominal ultrasound (TAUS) in most patients. In patients with atypical presentations or technically limited ultrasound (ovarian/iliac veins obscured by bowel gas), will occasionally get cross-sectional imaging with CT venography.

The ultrasound should guide the extent of further invasive evaluation. If there is evidence of concurrent ovarian vein reflux and iliac vein compression, I will also do iliac IVUS. If there is evidence of renal vein compression, I do IVUS, and renal vein pullback pressures (with or without balloon occlusion of the ovarian vein depending on the degree of suspicion).

Salazar: For most patients who will “fit“ the category of pelvic pain of venous origin, I will only request transvaginal ultrasound (TVUS) with evidence of 5 mm in diameter of peri-uterine veins. However, if the patient has suspected compression syndromes (left renal or iliac vein stenosis), I would order cross-sectional imaging (CTV/MRV).

Khilnani: There is not one ideal imaging test. In fact, one could consider that there are two imaging goals in this situation, one for screening and one for anatomical and physical evaluation, and each may have a different best strategy. For screening, a test that helps CPP physicians make decisions for patient care including identifying abnormal venous issues would be best. TVUS is frequently used by CPP gynecologists and is cheap, widely available, and highly reproducible, and allows screening for other CPP conditions as well.

For screening, I would label this as the best imaging test. TVUS cannot screen the common iliac veins for stenosis (although for the initialed, most of the external iliac veins (EIV) can be assessed). It is unclear at this point if the left common iliac vein (LCIV) non-thrombotic iliac vein lesion (NIVL) consistently leads to the same kind of varices as reflux does, so the TVUS may not identify VO-CPP from obstruction.

For diagnostic evaluation of women with a suggestive history and physical with or without pelvic varices already found on TVUS, a TAUS is a cost-effective way to identify varices, ovarian reflux, and iliac and renal vein obstruction, as well as to assess physiology as has already been mentioned. This can be accomplished with MRV by those without local expertise for TAUS, or CT with contrast. Both are limited by cost and CT is limited by ionizing radiation and lack of physiologic data regarding vessel flow and the severity of venous compressions.

Ultrasound demonstrates a dilated ovarian vein with retrograde flow and pelvic varices.

Question 3

How would you interpret the images shown, and what do you predict as the expected source of pelvic varices? Is it primarily ovarian vein reflux or iliac vein obstruction?

Meissner: L ovarian vein is dilated with retrograde flow and associated with per-adnexal varices. I would want to see more images of the iliac veins on transabdominal ultrasound, iliac vein velocities and a velocity ratio: flow direction in the left internal iliac vein.

For the IVUS, I would like to see how much respiratory variability there is and would also want to see a venogram with the catheter at the femoral head to specifically evaluate for internal iliac vein reflux, ascending lumbar collaterals and filling of pelvic varices/anterior division tributaries (uterine, vaginal, vesicle – not lateral sacral veins).

I would not feel entirely confident based on the limited imaging, but the degree of iliac vein compression does not look that severe on trans-abdominal ultrasound, and I would suspect 1º ovarian vein reflux.

Salazar: While there may be a component of compression in the left iliac vein, I believe that the primary source of pelvic varices (peri-uterine varices) is secondary to ovarian venous reflux, but I would like to know whether the patient also has left lower extremity symptoms related to venous disease and confirm with IVUS, if the procedure is indicated.

Winokur: This is very challenging to interpret in isolation with selected images showing dilated periuterine veins and a dilated left ovarian vein with retrograde flow. The assumption from these images is that the primary source of pelvic pain is ovarian vein reflux and the images of the left common iliac vein does not show a significant compression.

However, invasive imaging with venography and intravascular ultrasound would need to be performed to diagnose a NIVL as the source of pelvic varices and pelvic pain.

Based on these findings, I would favor ovarian vein reflux as the source of the pain and likely start treatment with ovarian vein embolization, but I would evaluate the left common iliac vein in greater detail during that procedure and prepare the patient that we may need to address obstruction if present in the future, and there is persistent or recurrent pelvic pain.

Question 4

How do you interpret non-thrombotic iliac vein lesions in the CPP population and how should we study the value as a part of future research trials?

Meissner:

1. On TAUS, I would like to see planimetric compression as well as a velocity ratio > 2.5 and retrograde flow in the internal iliac vein (a specific, but not very sensitive finding)

2. On femoral venography, I would like to see typical pancaking of the common iliac vein associated with ascending lumbar collaterals, internal iliac reflux, and filling of anterior division branches/pelvic varices as above (the latter is again very specific but not very sensitive). I put very little confidence in filling of posterior division branches (e.g. lateral sacral veins) as everyone is always showing at meetings.

3. If I don’t see any of the above on femoral venography, I will do selective left internal iliac venography, specifically looking at the flow patterns in the uterine and ovarian plexuses as well as the left ovarian vein.

Salazar: Given the overlapping presentations, I think we should study patients with isolated iliac vein stenosis separately from patients who present with both OV reflux and stenosis. The hemodynamics are also important and determining a threshold for clinically significant stenosis in both patient populations will be important to determine which lesions should be treated.

In the example above there is both area and maximal diameter reduction in the lumen, and I would consider stenting if symptoms correlate clinically. Winokur: It is extremely challenging in this situation to diagnose the significance of the NIVL since there is true compression by intravascular ultrasound with 73% stenosis during this procedure. However, pre-procedure imaging with ultrasound did not show a similar degree of compression. Additional data is needed to delineate the role of NIVL in causing venous origin CPP, and caution should be taken before defaulting to stent placement whenever a significant compression is seen using IVUS.

Question 5

What is your approach to ovarian vein embolization (OVE) at this time? Do you treat one, two, or four vessels and do you treat the pelvic varices? What studies are needed and/or expected to elicit the value of embolization in VO-CPP patients?

Meissner: I always treat the pelvic varices with 3% STS foam opacified with ethiodol.

I think non-invasive studies such as trans-abdominal U/S, CTV, or MRV are only a starting point as they reflect only the natural left-to-right flow bias in the pelvis. Once the left ovarian vein is embolized, the hemodynamics change and veins that did not seem to fill varices prior to embolization will now fill residual varices. I think all four vessels need to be evaluated and any vein that communicates with varices should be treated. Salazar: My current approach is to embolize incompetent and refluxing veins, which most commonly include bilateral ovarian veins and pelvic reservoir. In a subset of patients with a) internal iliac vein reflux and varices or b) internal iliac escape pelvic points, I would embolize these vessel territories.

At this point, we have established a great tool for defining the anatomy and symptoms of these patients with the Symptoms-Varices-Pathophysiology (SVP) tool, and we would benefit from prospective registry-type data to evaluate treatment outcomes and understand the incidence of reflux vs. obstruction. Long-term data will then include a controlled– prospective analysis of different treatment strategies and comparative studies to fully support interventional treatments in these patients.

Conclusion

Pelvic Venous Disorders (PeVD) require a complete clinical assessment and evaluation to identify the source of chronic pelvic pain. In order to complete the clinical assessment of these patients, it is important to obtain a clear clinical history to ask about associated/affiliated symptoms as detailed above. Once this is performed, an anatomic assessment of the pelvic venous system will allow physicians to differentiate those patients who do or do not have a venous origin for CPP.

Some providers can visualize the pelvic reservoir, ovarian veins, iliac veins, and renal veins with ultrasound. MRI and or CT can also provide clear imaging information to identify dilated ovarian veins or pelvic veins as well as iliac or renal vein compression.

Once pelvic varices and a pathophysiology of pelvic venous hypertension are identified, it is important to identify the best treatment algorithm such as ovarian vein embolization or iliac vein stent placement.

Multiple critical research trials are being organized due to the Society of Interventional Radiology Research Consensus Panel that helped produce the SVP classification tool. The first of these trials will provide clear information about venous origin and non-venous origin CPP with the hopeful creation of a disease-specific quality-of-life tool. Additional research studies evaluating the effectiveness of both ovarian vein embolization and iliac vein stenting are in progress. Hopefully, they will allow patients to have better access to the most appropriate procedure to treat their CPP.

Evaluation and treatment of venous origin chronic pelvic pain have incorporated a detailed clinical assessment and opportunity to improve patient quality of life through several treatment strategies in which endovascular specialists can play a large and important role.