Talk:Cardiovascular - Venous Development
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Cite this page: Hill, M.A. (2019, June 18) Embryology Cardiovascular - Venous Development. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Talk:Cardiovascular_-_Venous_Development
Venous Collateral Pathways in Superior Thoracic Inlet Obstruction: A Systematic Analysis of Anatomy, Embryology, and Resulting Patterns
AJR Am J Roentgenol. 2019 Apr 30:1-11. doi: 10.2214/AJR.18.20172. [Epub ahead of print]
Meier A1, Alkadhi H1.
OBJECTIVE. For this study, we reviewed 56 standard-of-care CT examinations over a timespan of 2 years from patients with superior thoracic inlet venous obstruction and identified eight thoracic collateral pathways for venous blood return to the right heart. We evaluated each pathway individually from an anatomic and a pathophysiologic perspective for a better understanding of how such pathways form and what patterns can be expected. MATERIALS AND METHODS. All 56 patients were scanned according to our standard CT protocol. Images of the thoracic region were acquired in the craniocaudal direction during breath-holding using a second-generation dual-source CT scanner. Contrast medium was administered via a cubital or antecubital vein; the amount of contrast material ranged from 49 to 81 mL depending on patient body weight. RESULTS. Of the 56 patients, CT showed superior vena cava syndrome exclusively in 22 (39%) patients and showed superior vena cava syndrome and involvement of the left or right brachiocephalic vein or even the subclavian vein in the remaining 34 (61%) patients. We could not find any remarkable feature leading to the formation of only one collateral pathway or to a specific pattern depending on underlying cause or the level or the extent of obstruction. Thus, we believe that there are no specific patterns for how these venous detours form and that they are most probably driven by pressure gradients. CONCLUSION. Recognizing imaging findings associated with venous collateral pathways may prevent misdiagnosis or unnecessary follow-up examinations. Furthermore, knowledge of these collateral pathways and an understanding of the underlying cause can support interventional radiologists and vascular surgeons in planning interventional procedures and revascularization procedures. KEYWORDS: superior thoracic inlet venous obstruction; venous collateral pathways PMID: 31039029 DOI: 10.2214/AJR.18.20172
Infrahepatic inferior caval and azygos vein formation in mammals with different degrees of mesonephric development
J Anat. 2016 Mar;228(3):495-510. doi: 10.1111/joa.12423. Epub 2015 Dec 11.
Hikspoors JP1, Mekonen HK1, Mommen GM1, Cornillie P2, Köhler SE1, Lamers WH1,3.
Controversies regarding the development of the mammalian infrahepatic inferior caval and azygos veins arise from using topography rather than developmental origin as criteria to define venous systems and centre on veins that surround the mesonephros. We compared caudal-vein development in man with that in rodents and pigs (rudimentary and extensive mesonephric development, respectively), and used Amira 3D reconstruction and Cinema 4D-remodelling software for visualisation. The caudal cardinal veins (CCVs) were the only contributors to the inferior caval (IVC) and azygos veins. Development was comparable if temporary vessels that drain the large porcine mesonephros were taken into account. The topography of the CCVs changed concomitant with expansion of adjacent organs (lungs, meso- and metanephroi). The iliac veins arose by gradual extension of the CCVs into the caudal body region. Irrespective of the degree of mesonephric development, the infrarenal part of the IVC developed from the right CCV and the renal part from vascular sprouts of the CCVs in the mesonephros that formed 'subcardinal' veins. The azygos venous system developed from the cranial remnants of the CCVs. Temporary venous collaterals in and around the thoracic sympathetic trunk were interpreted as 'footprints' of the dorsolateral-to-ventromedial change in the local course of the intersegmental and caudal cardinal veins relative to the sympathetic trunk. Interspecies differences in timing of the same events in IVC and azygos-vein development appear to allow for proper joining of conduits for caudal venous return, whereas local changes in topography appear to accommodate efficient venous perfusion. These findings demonstrate that new systems, such as the 'supracardinal' veins, are not necessary to account for changes in the course of the main venous conduits of the embryo. © 2015 Anatomical Society. KEYWORDS: azygos vein; caudal cardinal veins; human; inferior caval vein; mesonephros; mouse; pig
PMID 26659476 DOI: 10.1111/joa.12423