DOI: 10.1148/rg.245035224
Preoperative Hepatic Vascular Evaluation with CT and MR Angiography: Implications for Surgery1
Dushyant Sahani, MD,
Aparna Mehta, MBBS, DMRE,
Michael Blake, MD,
Srinivasa Prasad, MD,
Gordan Harris, PhD and
Sanjay Saini, MD
1 From the Division of Abdominal Imaging and Intervention, Departments of Radiology (D.S., A.M., M.B., S.P., S.S.) and 3D Image Processing (G.H.), Massachusetts General Hospital, White 270, 55 Fruit St, Boston, MA 02114. Presented as an education exhibit at the 2001 RSNA scientific assembly. Received December 12, 2003; revision requested January 20, 2004; final revision received February 25; accepted March 9. All authors have no financial relationships to disclose. Address correspondence to D.S. (e-mail: dsahani@partners.org).
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Figure 1. Sagittal T1-weighted MR image demonstrates placement of a 3D slab. For MR angiography of the liver and mesenteric arteries, the 3D slab should be placed anteriorly covering the aorta to include the superior mesenteric and celiac arteries.
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Figure 2. Three-dimensional MIP image from CT data demonstrates the hepatic venous confluence in which the left hepatic vein (LHV) (solid arrow) and middle hepatic vein (MHV) (open arrow) form a common trunk extrahepatically before joining to form the inferior vena cava (IVC). This configuration is important in left lateral resection, since the surgeon can simply clamp the LHV extrahepatically and then secure the venous drainage to the graft. The MHV is secured to preserve the venous drainage of segment IV.
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Figure 3a. Reformatted images from CT (a) and MR imaging (b) data depict the normal course and branching pattern of the hepatic artery. Note that in a, the gastroduodenal artery (curved arrow) branches off from the common hepatic artery (CHA). The proper hepatic artery divides into the left hepatic artery (LHA) and right hepatic artery (RHA). CA = celiac artery, SMA = superior mesenteric artery.
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Figure 3b. Reformatted images from CT (a) and MR imaging (b) data depict the normal course and branching pattern of the hepatic artery. Note that in a, the gastroduodenal artery (curved arrow) branches off from the common hepatic artery (CHA). The proper hepatic artery divides into the left hepatic artery (LHA) and right hepatic artery (RHA). CA = celiac artery, SMA = superior mesenteric artery.
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Figure 4a. (a) Curved two-dimensional reformatted image from CT data depicts the entire course of the replaced LHA (Michel type II variant) (arrow) from the left gastric artery. (b) Catheter angiogram shows the same arterial anatomy. This anomaly in a donor does not influence pediatric split liver transplantation. However, in left lobe transplantation, surgical technique must be modified in the donor, since two left hepatic arteries are anastomosed. LHA = left hepatic artery, Left Gastric = left gastric artery.
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Figure 4b. (a) Curved two-dimensional reformatted image from CT data depicts the entire course of the replaced LHA (Michel type II variant) (arrow) from the left gastric artery. (b) Catheter angiogram shows the same arterial anatomy. This anomaly in a donor does not influence pediatric split liver transplantation. However, in left lobe transplantation, surgical technique must be modified in the donor, since two left hepatic arteries are anastomosed. LHA = left hepatic artery, Left Gastric = left gastric artery.
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Figure 5. Axial CT scan demonstrates the normal draining pattern of the hepatic veins. The LHV and MHV form a common trunk (arrow) that drains into the IVC.
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Figure 6. On an axial 3D MIP-VR image from MR angiographic data, the MHV and LHV join to form a common trunk (large arrow) that drains into the IVC. RHV = right hepatic vein.
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Figure 7. Schematic illustrates the transection plane (arrows) used in right lobe liver transplantation. The surgical plane extends craniocaudally to the right of the MHV. The MHV drains segment IV and therefore is carefully preserved with the remnant liver of the donor.
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Figure 8. Schematic illustrates pediatric left lobe liver transplantation, with a hepatectomy plane to the left of the MHV. Structures at the liver hilum, which include the bile duct (arrowhead), hepatic artery (solid arrow), and portal vein (open arrow), are carefully dissected.
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Figure 9. Intraoperative photograph shows the resection plane used in liver donor surgery. Note the positioning of clamps along the portal vein (open arrow), hepatic artery (arrowhead), and hepatic vein (solid arrow) to secure the pedicle of the transplant graft.
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Figure 10. Coronal reformatted image from CT data demonstrates an accessory RHV (open arrow) draining separately into the IVC (arrowhead). This accessory vein measured over 4 mm in diameter and was located more than 5 cm from the insertion site of the main RHV (solid arrow) into the IVC. An accessory RHV is separately anastomosed with the graft in a recipient, a procedure that increases the complexity of transplant surgery.
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Figure 11a. Venous phase CT scan (a) and axial T1-weighted MR image (b) reflect the limitations of CT in demonstrating small hepatic veins: The MR image demonstrates two small accessory RHVs (arrows) that are not visualized on the CT scan.
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Figure 11b. Venous phase CT scan (a) and axial T1-weighted MR image (b) reflect the limitations of CT in demonstrating small hepatic veins: The MR image demonstrates two small accessory RHVs (arrows) that are not visualized on the CT scan.
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Figure 12. Schematic illustrates variant venous drainage for segment IV, which is drained by a branch of the LHV (curved arrow). The MHV drains segments V and VIII. Therefore, for right hepatectomy, the resection plane will run to the left of the MHV.
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Figure 13. Axial CT scan demonstrates the transection planes used in right lobe liver transplantation (black lines). The presence of portal vein trifurcation increases the complexity of the surgery. The right anterior (open arrow) and posterior (solid black arrow) veins would have to be ligated individually.
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Figure 14. MIP image from MR imaging data demonstrates the Michel type II variant, in which the replaced LHA (long solid arrow) originates from the left gastric artery (straight open arrow) and the MHA (short solid arrow) arises from the proper hepatic artery (curved open arrow). In cases of left lobe tumor, the surgical technique would have to be modified: The LHA would have to be ligated at its origin from the left gastric artery.
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Figure 15. Three-dimensional VR image (inferior oblique view) from CT angiographic data demonstrates trifurcation of the portal vein (curved solid arrow) into the right anterior (straight solid arrow), right posterior (arrowhead), and left portal (open arrow) veins. Thus, in cases of right lobe tumor, these three latter veins must be ligated individually to preserve the portal venous supply to the left hepatic lobe.
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Figure 16. MIP image from CT angiographic data shows a replaced RHA arising from the superior mesenteric artery (SMA). For chemotherapy pump placement, the replaced RHA is ligated beforehand to optimize the chemotherapy. CA = celiac artery, LHA = left hepatic artery.
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Figure 17. Axial MIP image from CT angiographic data demonstrates early branching of the celiac artery (CA) into the LHA, RHA, and splenic artery (black arrow). The presence of this arterial variant necessitates modification of the surgical technique for intraarterial chemotherapy pump placement. The pump catheter is placed in the dominant hepatic artery, and the other branch is usually ligated.
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Copyright © 2004 by the Radiological Society of North America.
