Beard Criteria
The Beard criteria were originally developed as an image-based venographic scoring system incorporating maximum ovarian vein diameter, time of contrast disappearance, and a subjective grade of ovarian plexus congestion. A score ≥5 achieved 91% sensitivity and 89% specificity for PeVD.
Chung and Huh subsequently modified the criteria for catheter-directed venography, defining PeVD when the following are met on selective injection (treat with embolization when criteria are satisfied):
| # | Modified Beard Criterion (Chung & Huh) |
|---|---|
| 1 | Ovarian vein diameter ≥6 mm |
| 2 | Contrast medium retention for >20 seconds after selective injection |
| 3 | Existence of congestion in the pelvic venous plexus and/or opacification of the ipsilateral or contralateral internal iliac vein |
| 4 | Filling of vulvovaginal and/or thigh varices |
Practical note: Ovarian vein size alone is an unreliable criterion. Large veins may be competent; small veins may reflux pathologically. The right ovarian vein may dilate compensatorily when the left is incompetent. Reflux on Valsalva is the more reliable diagnostic indicator across all modalities.
Transabdominal Ultrasound
Technique (Labropoulos protocol):
- 1–5 MHz curvilinear probe; patient supine and reclined to 30 degrees (instructed to fast the prior night to reduce bowel gas obstruction)
- Vessels assessed: IVC, left renal vein, iliac veins, ovarian veins, trans- and periuterine veins, and tributaries of the internal iliac veins
- Modalities: greyscale, color, and spectral Doppler
- Diagnostic maneuvers: Valsalva, manual compression near the iliac fossa, or standing position
| Finding | Significance / Data |
|---|---|
| Reversed, caudal flow in ovarian vein | Steenbeek: sensitivity 100% for detecting PeVD (95% CI 84–100%) |
| Left ovarian vein diameter >6 mm | Malgor: sensitivity 100%, specificity 67% for left OV; sensitivity 57%, specificity 90% for right OV |
| Velocity ratio (VR) in iliac veins ≥2.5 | For May-Thurner: sensitivity 76%, specificity/PPV 100%, NPV 87.5% |
| Small-caliber left CIV with thickened walls and continuous venous flow | Suggests May-Thurner syndrome (Barry criteria) |
| Left CIV diameter <50% of right CIV | Threshold for May-Thurner on transverse imaging at bifurcation |
Limitations: bowel gas, body habitus, operator dependence. Challenging to visualize the ovarian vein origin where flow is slow. In ≥20% of patients, iliac veins and their flow abnormalities cannot be adequately assessed by US alone.
Transvaginal Ultrasound (TVUS)
TVUS is an important adjunct to transabdominal sonography and can be performed simultaneously in the supine or semi-upright position.
Holdstock and/or Harrison protocol: evaluates the labial, ovarian, and internal iliac veins and their branches for reflux >1 second and varix dilatation on Valsalva — assessing ipsilateral syphoning, contralateral dilation and syphon effects, and trunk diameter.
| Finding | Data |
|---|---|
| Vein >5 mm crossing the uterine body | Specificity 91% for PeVD |
| Pelvic varicoceles on TVUS | Sensitivity 100%, specificity 83–100% |
| Structural uterine/ovarian changes | Cystic ovarian changes in ~50% of PeVD patients; bilateral ovarian enlargement; important to document |
Limitations: falls short for iliac vein assessment. Does not evaluate the more cranial abdominal venous structures (left renal vein, IVC).
MRI / MRV / MRA
MRI avoids ionizing radiation and is preferred in young women when US is indeterminate or structural detail is needed. Useful for excluding non-vascular pelvic pathology (endometriosis, adenomyosis, fibroids, malignancy).
| Technique | Description |
|---|---|
| Standard MRV | T1-weighted coronal 3D gradient echo; gadolinium IV contrast in multiple phases; images from above the renal veins through the mid-thighs |
| TR-MRA (time-resolved) | TWIST (Siemens), TRICKS (GE), or 4D-TRAK; sequences during arterial-to-corticomedullary (20–30 s) and delayed (65–95 s) phases show reflux from renal veins into ovarian veins |
| PCVM | Phase-contrast velocity mapping — quantifies directionality and velocity of venous flow; correctly diagnosed 100% of women with PeVD in a 9-person prospective comparison study |
MRI Reflux Grading
| Grade | MRI Finding |
|---|---|
| Grade I | Early filling of left ovarian vein and/or left parauterine veins |
| Grade II | Grade I + right ovarian vein reflux or internal iliac vein reflux (left and/or right) |
| Grade III | Ovarian vein diameter >8 mm |
| Grade IV | ≥4 ipsilateral pelvic veins measuring ≥4 mm |
| Metric | Performance |
|---|---|
| MRV sensitivity vs phlebography | 88% |
| MRV specificity vs phlebography | 67% |
| TR-MRA sensitivity | 66.7–75% |
| TR-MRA specificity | 100% |
| TR-MRA diagnostic accuracy | 78.9–84.2% |
| MRV for hypogastric veins: sensitivity / specificity | 100% / 91% |
| MRV for pelvic plexus: sensitivity / specificity | 38% / 42% |
TR-MRA (TRICKS) identified reflux better than conventional T2 imaging and reliably differentiated between Grades I, II, and III reflux. Yang found no significant difference between TR-MRA and conventional venography in grading ovarian vein reflux. Dick et al. confirmed TR-MRA superiority over static T2.
CT Venography
Less commonly used than sonography and MRI due to ionizing radiation in a predominantly young female population, but valuable when MRI is unavailable or contraindicated. CT provides excellent visualization of varicosities in the lower pelvis — greater sensitivity than US Doppler — and demonstrates structural causes including nutcracker and May-Thurner anatomy.
| Parameter | Detail |
|---|---|
| Position | Supine; deep breath hold increases intraabdominal pressure and accentuates OV reflux (mimics Valsalva) |
| Contrast timing | Arterial/corticomedullary phase (20–30 s); delayed venous phase (65–95 s) to show abnormal enhancement of pelvic and parauterine varicosities |
| Coverage | Upper abdomen (above renal veins) through mid-thighs — captures full venous territory |
| Post-processing | MPR, 3D volume rendering, MIP for vascular display |
| Sensitivity / specificity for DVT | 100% / 96% (Chung protocol) — critical for May-Thurner workup |
Chung found high correlation between CT venography and conventional venography. CT has lower overall diagnostic sensitivity than MRI/MRV for PeVD but is the preferred modality for evaluating bony pelvis, IVC, and iliac vessel anatomy before stenting.
Catheter Venography, IVUS, and Pressure Measurements
Retrograde catheter venography remains the diagnostic gold standard and is recommended when intervention is planned (SVS/AVF Grade 1C). Venous access is typically via the common femoral vein, jugular vein, or popliteal vein.
Venographic Protocol
- Selective injection of the left renal vein, ovarian veins, and bilateral internal iliac veins
- Diagnostic maneuvers: Valsalva and elevating the head of the table to accentuate or reveal reflux
- Specificity: 80–100%
- Disadvantages: ionizing radiation, IV contrast, cost, invasiveness
IVUS (Intravascular Ultrasound)
| Application | Data / Benefit |
|---|---|
| Identifies lesions missed by 3-view venography | 26.3% of patients |
| Changed treatment plans vs venography alone | >50% of patients |
| Agreement with duplex US for significant obstruction | High level of agreement (Metzger) |
| Morphology characterization | Chronic thrombotic change, wall thickening, intraluminal spurs, trabecula, webs |
| Pre-stent planning | Normal lumen area vs area of maximal stenosis; IVUS catheter markers estimate lesion and stent length |
| Post-stent assessment | Ensures accurate placement and wall apposition; measures post-intervention lumen areas |
Pressure Measurements
- Intravenous pressures acquired after establishing venous access
- Measured both centrally (IVC) and peripherally (external iliac vein)
- No significant pressure difference between lower IVC and external iliac vein = normal
- Gradient ≥2 mmHg = significant; confirms May-Thurner syndrome hemodynamically
- Absence of gradient does not exclude significant obstruction — collaterals can lower inflow pressures
May-Thurner Syndrome Imaging
May-Thurner syndrome (MTS) refers to left common iliac vein (LCIV) compression by the right common iliac artery against the lumbar vertebra posteriorly. It is an escape point for blood from the left lower extremity, increasing pelvic reservoir pressure and driving ovarian vein reflux as a secondary phenomenon.
Ultrasound
- Measure LCIV at the exact site of right common iliac artery crossing — best done in transverse at the bifurcation
- LCIV diameter <50% of right CIV = suspicious for MTS
- Velocity ratio (VR) ≥2.5: sensitivity 76%, specificity and PPV 100%, NPV 87.5%
- Color Doppler for thrombosis: sensitivity 87%, specificity 83%
- Small-caliber LCIV with thickened walls and continuous (non-phasic) venous flow suggests MTS
- IVUS on US catheter: can visualize intraluminal spurs, webs, thrombus that standard imaging misses
MRI / CT
- Standard MRA and CT venography protocols apply; field of view focused on the pelvis
- CT sensitivity 100%, specificity 96% for DVT in MTS context
- MPR and 3D MIP for iliac vein and artery relationship
- Look for intraluminal filling defects, collateral pelvic veins, and left lower extremity venous dilatation
Venography + Pressure
- Selective iliac venography with attention to collateral vessels and pelvic venous congestion
- Pressure gradient ≥2 mmHg between LCIV and IVC = hemodynamically significant obstruction
- IVUS is especially valuable — identifies lesions not seen on 3-view venography, directly guides stent sizing and placement
Nutcracker Syndrome Imaging
Nutcracker syndrome results from compression of the left renal vein (LRV) between the aorta posteriorly and the superior mesenteric artery (SMA) anteriorly. This increases left renal vein pressure, causing retrograde flow down the left ovarian vein into the pelvic reservoir — a secondary cause of PeVD.
Ultrasound
- Using the Labropoulos abdominal protocol; patients fast prior; 1–5 MHz low-frequency probe
- Measure AP diameter and peak velocities (PV) at the renal hilum and at the level of the SMA
- PV ratios <4–5 between the narrowed (aortomesenteric) and dilated (renal hilar) segments = normal
- AP diameter ratio and PV ratio together are more predictive than either alone — peak velocities can vary with patient positioning
- Transvaginal US: limited utility for more cranial abdominal structures
MRI / CT
- Cross-sectional imaging with field of view covering the kidneys
- Demonstrates aortomesenteric angle and distance, LRV compression, and left renal vein dilatation proximal to the SMA
- Left renal vein diameter ratio (hilum / aortomesenteric segment) >4.9 on CT is suggestive
- Look for left renal vein collaterals (left gonadal vein, left adrenal vein, lumbar veins) indicating outflow obstruction
Venography + IVUS
- Selective left renal venogram; pressure measurements across the aortomesenteric segment
- IVUS used for pre-stent assessment — evaluates stent length, lumen area, and post-placement apposition
Recommended Imaging Algorithm
| Step | Modality | Indication |
|---|---|---|
| 1st line | Transabdominal US ± TVUS | All patients with suspected PeVD; dynamic, no radiation, evaluates reflux in real time |
| 2nd line | MRI/MRV or CT venography | US limited (bowel gas, body habitus, obese); structural detail needed (exclude endometriosis, fibroids); pre-treatment mapping; suspected May-Thurner or nutcracker |
| Definitive / pre-treatment | Catheter venography ± IVUS ± pressures | When intervention is planned (SVS/AVF Grade 1C); IVUS strongly recommended when MTS or nutcracker is suspected |
| Avoid | Laparoscopy | CO&sub2; pneumoperitoneum compresses pelvic veins — poor sensitivity for venous congestion |
References
- Topper SR, Winokur RS. Imaging of Pelvic Venous Disorders (PeVD); Should Every Patient Get an MRI? Tech Vasc Interventional Rad. 2021;24:100731. doi:10.1016/j.tvir.2021.100731.
- Meissner MH, Khilnani NM, Labropoulos N, et al. The SVP Classification of Pelvic Venous Disorders. J Vasc Surg Venous Lymphat Disord. 2021;9(3):568–584.
- Bookwalter CA, VanBuren WM, Neisen MJ, Bjarnason H. Imaging Appearance and Nonsurgical Management of Pelvic Venous Congestion Syndrome. Radiographics. 2019;39(2):596–608.
- Vedantham S, Weinberg I, Desai KR, et al. SIR Position Statement on Chronic Iliofemoral Venous Obstruction With Endovascular Stents. J Vasc Interv Radiol. 2023;34(10):1643–1657.
- Related guides: PeVD embolization · varicocele embolization · IVC filter placement