Article

Transhepatic portal vein embolization: anatomy, indications, and technical considerations.

Department of Diagnostic Imaging, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Box 57, Houston, TX 77030-4009, USA.
Radiographics (Impact Factor: 2.79). 22(5):1063-76.
Source: PubMed

ABSTRACT Portal vein embolization (PVE) is increasingly being accepted as a useful procedure in the preoperative treatment of patients selected for major hepatic resection. PVE is performed via either the percutaneous transhepatic or the transileocolic route and is usually reserved for patients whose future liver remnants are too small to allow resection. It is a safe and effective method for inducing selective hepatic hypertrophy of the nondiseased portion of the liver and may thereby reduce complications and shorten hospital stays after resection. A thorough knowledge of hepatic segmentation and portal venous anatomy is essential before performing PVE. In addition, the indications and contraindications for PVE, the methods for assessing hepatic lobar hypertrophy, the means of determining optimal timing of resection, and the possible complications of PVE need to be fully understood before undertaking the procedure. Technique may vary among operators, and further research is necessary to determine the best embolic agents available and the expected rates of liver regeneration for PVE. Nevertheless, as hepatobiliary surgeons become more experienced at performing extended hepatic resections, PVE may be requested more frequently.

1 Bookmark
 · 
60 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Portal vein occlusion through embolization or ligation (PVE, PVL) offers the possibility of increasing the future liver remnant (FLR) and thus reducing the risk of hepatic failure after extended hepatectomy We reviewed the indications, scope and applicability of PVE/PVL in treatment of primary and secondary liver tumours. A thorough PubMED, Embase, Ovid and Cochrane database search was carried out for all original articles with 30 patients or more undergoing either PVE and any patient series with PVL, irrespective of number with outcome measure in at least one of the following parameters: FLR volume change, complications, length of stay, time to surgery, proportion resectable and survival data. PVE can be performed with a technical success in 98.9 % (95 % confidence interval 97-100) patients, with a mean morbidity of 3.13 % (95 % CI 1.21-5.04) and a median in-hospital stay of 2.1 (range 1-4) days (very few papers had data on length of stay following PVE). The mean increase in volume of the FLR following PVE was 39.75 % (95 % CI 30.8-48.6) facilitating extended liver resection after a mean of 37.13 days (95 % CI 28.51-45.74) with a resectability rate of 76.88 % (95 % CI 70.91-82.84). Morbidity and mortality following such extended liver resections after PVE is 26.58 % (95 % CI 19.20-33.95) and 2.59 % (95 % CI 1.34-3.83) respectively with an in-patient stay of 13.57 days (95 % CI 9.8-17.37). However following post-PVE liver hypertrophy 6.29 % (95 % CI 2.24-10.34) patients still have post-resection liver failure and up to 14.2 % (95 % CI -8.7 to 37) may have positive resection margins. Up to 4.80 % (95 % CI 2.07-7.52) have failure of hypertrophy after PVE and 17.46 % (95 % CI 11.89-23.02) may have disease progression during the interim awaiting hypertrophy and subsequent resection. PVL has a greater morbidity and duration of stay of 5.72 % (95 % CI 0-15.28) and 10.16 days (95 % CI 6.63-13.69) respectively; as compared to PVE. Duration to surgery following PVL was greater at 53.6 days (95 % CI 32.14-75.05). PVL induced FLR hypertrophy by a mean of 64.65 % (95 % CI 0-136.12) giving a resectability rate of 63.68 % (95 % CI 56.82-70.54). PVL failed to produce enough liver hypertrophy in 7.4 % of patients (95 % CI 0-16.12). Progression of disease following PVL was 29.29 (95%CI 15.69-42.88). PVE facilitates an extended hepatectomy in patients with limited or inadequate FLR, with good short and long-term outcomes. Patients need to be adequately counselled and consented for PVE and EH in light of these data. PVL would promote hypertrophy as well, but clearly PVE has advantages as compared to PVL on account of its inherent "minimally invasive" nature, fewer complications, length of stay and its feasibility to have shorter times to surgery.
    Indian journal of surgical oncology. 03/2014; 5(1):30-42.
  • [Show abstract] [Hide abstract]
    ABSTRACT: To examine the efficacy and safety of portal vein embolization (PVE) when used during two-stage hepatectomy for bilobar colorectal liver metastases (CLM). PVE was performed as an adjunct to two-stage hepatectomy in 56 patients with CLM. Absolute future liver remnant (FLR) volumes, standardized FLR ratios, degree of hypertrophy (DH), and complications were analyzed. Segment II and III volumes and DH were also measured separately. All volumetric measurements were compared with a cohort of 96 patients (n = 37 right portal vein embolization [RPVE], n = 59 right portal vein embolization extended to segment IV portal veins [RPVE+4]) in whom PVE was performed before single-stage hepatectomy. For patients who completed RPVE during two-stage hepatectomy (n = 17 of 17), mean absolute FLR volume increased from 272.1 cm(3) to 427.0 cm(3) (P < .0001), mean standardized FLR ratio increased from 0.17 to 0.26 (P < .0001), and mean DH was 0.094. For patients who completed RPVE+4 during two-stage hepatectomy (n = 38 of 39), mean FLR volume increased from 288.7 cm(3) to 424.8 cm(3) (P < .0001), mean standardized FLR increased from 0.18 to 0.26 (P < .0001), and mean DH was 0.083. DH of the FLR was not significantly different between two-stage hepatectomy and single-stage hepatectomy. Complications after PVE occurred in five (8.9%) patients undergoing two-stage hepatectomy. PVE effectively and safely induced a significant DH in the FLR during two-stage hepatectomy in patients with CLM.
    Journal of vascular and interventional radiology: JVIR 12/2013; · 1.81 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose To retrospectively analyze the degree of artefacts in CT and MRI scans caused by coils and vascular plugs used for portal vein embolization (PVE). Materials and Methods All patients who underwent PVE between July 2011 and December 2012 and received either plug or coil embolization additional to particle embolization were retrospectively analyzed. Artefacts causes by embolization materials were measured in CT and MRI scans following PVE. Results The sum of the artefact diameters caused from coils was significantly higher in CT (188.3 ± 26.1 mm) than in MRI T1 (50.5 ± 6.5 mm) or T2 imaging (39.5 ± 9.7 mm) (P < 0.05). In MRI, the diameter in T1 and T2 sequences did not differ significantly (P = 0.977). The sum of the artefact diameters from vascular plugs in MRI T1 sequences (62.5 ± 8.7 mm) were significantly higher than in CT (46.6 ± 4.8 mm; P < 0.05) and MRI T2 sequences (52.8 ± 3.8 mm; P < 0.05). Conclusion PVE with particles and vascular plug causes significantly fewer artefacts than PVE with particles and coils on CT scans following embolization, which can be important in the event of vascular complications or in follow-up scans, should the patient become unresectable.
    European journal of radiology 01/2014; · 2.65 Impact Factor