Retrograde flow in the left ovarian vein is a shunt, not reflux Poster No.: C-0846 Congress: ECR 2013 Type: Scientific Exhibit Authors: R. Livsey; Brisbane/AU Keywords: Genital / Reproductive system female, Interventional vascular, Pelvis, CT-High Resolution, Catheter venography, UltrasoundColour Doppler, Embolisation, Computer Applications-Detection, diagnosis, Varices DOI: 10.1594/ecr2013/C-0846 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. www.myesr.org Page 1 of 26
Purpose To demonstrate the significance of reverse flow in the Left Ovarian Vein, (LOV) by review of routine Portal phase MDCT of Abdomen and Pelvis. Fig. 1: Dense enhancement of LOV, none of IVC References: Medical Imaging, Mater Health Services - Brisbane/AU Page 2 of 26
Images for this section: Fig. 1: Dense enhancement of LOV, none of IVC Page 3 of 26
Methods and Materials The use of MDCT has given new understanding of this finding. The routine use of IV contrast in the portal phase, and the rapid aquisition, allows clear identification of direction of flow in a large LOV.Scans are commonly timed when there is dense enhancement of the renal veins, but before enhancement of the lower IVC and other abdominal veins. Under these conditions enhancement of the LOV must mean retrograde flow, the enhanced blood comes from the Left Renal Vein(LRV) and is passing to the pelvis. There is no pathway in the pelvis to give this early enhancent to the LOV except perhaps a very rare AVM. The enhanced blood must come from above, not be passing superiorly. Why do we find contrast passing down the left ovarian vein? When this prominent, enhanced LOV is seen it is worth reviewing the left renal vein. This will usually be compressed. There may be vascular compression, usually SMA on Aorta(Nutcracker) Fig. 2 on page 4 or compression by tumour mass or other abnormal tissue. Occasionally there is no Nutcracker, no obstructing lesion of the left renal vein and I cannot explain this. Images for this section: Page 4 of 26
Fig. 2: Look at the LRV Page 5 of 26
Results The compromised LRV drainage is compensated by the development of alternative pathways. The blood has to return to the heart. In a woman the major one is via the LOV. Another path, paticularly in men, is via a collateral from the posterior surface of LRV to connect with paraspinal veins and the hemiazygos system. The LOV flow has alternate routes in the pelvis:.to Left IIV or -Via Left broad ligament to Arcuate Veins of uterus to Right broad ligament, and then either to -Right IIV or -Right Ovarian Vein,where it can be seen passing superiorly. On occasion a jet can be seen passing into the non opacified IVC from the insertion of the Ovarian Vein, confirming the direction of flow. Fig. 3 on page 21 Page 6 of 26
Fig. 3 References: Roger Livsey Page 7 of 26
Fig. 4 References: Medical Imaging, Mater Health Services - Brisbane/AU The literature comments on these pelvic veins,the veins of the broad ligament etc. but does not really mention the fact that the shunt across the pelvis is completed by the venous plexus, the arcuate veins, of the myometrium. This can be shown clearly on MDCT. Page 8 of 26
Fig. 5: CORONAL MIPS, Flow down the LOV, across myometrium,up the ROV References: Medical Imaging, Mater Health Services - Brisbane/AU Page 9 of 26
Fig. 6: Sagittal MIPS showing flow through myometrium References: Medical Imaging, Mater Health Services - Brisbane/AU Fig. 7: Transverse MIPS showing flow through myometrium References: Medical Imaging, Mater Health Services - Brisbane/AU The continuity of broad ligament and uterine veins is shown in this HSG that shows venous intravasation and flow to Internal Iliac and Ovarian Veins Page 10 of 26
Fig. 8: Hystero-Salpingogram with intravasation References: Medical Imaging, Mater Health Services - Brisbane/AU What happens in men who have Nutcracker which is associated with varicocele? The left kidney still has to drain. The left testicular vein is not a shunt vein. It does not anastomosis with anything significant, merely passes to the testis in an isolated chamber. The appearance of dilated left testicular vein is not common in a man. Other collateral pathways such as the paraspinal veins are important. Page 11 of 26
Fig. 9: Posterior collateral from LRV due to Nutcracker References: Medical Imaging, Mater Health Services - Brisbane/AU Page 12 of 26
Fig. 10: 10mm higher, the collateral passing beside the vertebra, travels cephalad from here. References: Medical Imaging, Mater Health Services - Brisbane/AU Page 13 of 26
Fig. 11: Cephalad flow in Left Paraspinal Vein References: Medical Imaging, Mater Health Services - Brisbane/AU Compression of the LRV may be less common in men because there is no easy alternative path, the LRV cannot collapse so easily across the aorta. Nutcracker is easily missed at venography. The left renal vein is compressed as it crosses aorta. During venography this stenosis has been crossed when the catheter shows the left gonadal vein. Any difficulty entering the LOV will have been counted as a technical problem, not evidence of pathology. Very hard to show a nutcracker venographically. Images for this section: Page 14 of 26
Fig. 5: CORONAL MIPS, Flow down the LOV, across myometrium,up the ROV Fig. 6: Sagittal MIPS showing flow through myometrium Page 15 of 26
Fig. 7: Transverse MIPS showing flow through myometrium Page 16 of 26
Fig. 9: Posterior collateral from LRV due to Nutcracker Page 17 of 26
Fig. 10: 10mm higher, the collateral passing beside the vertebra, travels cephalad from here. Page 18 of 26
Fig. 11: Cephalad flow in Left Paraspinal Vein Page 19 of 26
Fig. 4 Page 20 of 26
Fig. 8: Hystero-Salpingogram with intravasation Page 21 of 26
Fig. 3 Page 22 of 26
Conclusion Traditionally reverse flow in the LOV has been considered, against all rational and empiric processes, to be a gravitational phenomenon. Understanding the significance of early enhancement of the LOV refutes this theory. Pelvic Congestion.Nutcracker seems an important component which has not been understood.pregnancy allows the shunt veins in the pelvis and uterus to dilate, becoming varicose Even so it is not clear what makes one lady suffer pelvic congestion and another not when they both have the LRV draining via the pelvis. Other points to consider include -The pelvic varices are visible at laparoscopy, in the Trendelenberg position. Page 23 of 26
Fig. 12: Pelvic veins bulging at laparoscopy, Trendelenberg position References: Medical Imaging, Mater Health Services - Brisbane/AU -In the erect position the sump of the pelvis is occupied by organs other than just blood vessels- something has to inflate the pelvic veins against this, ie the shunt. -The veins should distend more in an unsupported extraperitoneal varicocele than inside the abdominal cavity if gravity is the driving force Management implications. Interventional management of pelvic congestion would benefit from CT clarification of LRV anatomy The main thrust of the treatment is to divert the shunt, usually by blocking the LOV, sometimes by direct treatment of the LRV by surgery or stenting. Page 24 of 26
Images for this section: Fig. 12: Pelvic veins bulging at laparoscopy, Trendelenberg position Page 25 of 26
References Nil No previous reference to reverse flow in the Left Ovarian Vein being part of a shunt draining the Left Kidney has been found Personal Information Page 26 of 26