Intraoperative Doppler ultrasound in living-related liver transplantation

Intraoperative Doppler sonogram in pediatric liver transplants: a pictorial review of intraoperative and early postoperative complications

A spectrum of vascular complications can be seen in pediatric liver transplant patients, including occlusion and hemodynamically significant narrowing of the vessels that provide inflow to or outflow from the graft. Intraoperative Doppler ultrasound (US) has the potential benefit of identifying vascular complications in pediatric liver transplant patients prior to abdominal closure. Importantly, intraoperative Doppler US can be used as a problem-solving tool in situations such as position-dependent kinking of the portal or hepatic veins, or in suspected vasospasm of the hepatic artery. Furthermore, this technique can be used for real-time reassessment after surgical correction of vascular complications. This pictorial review of intraoperative Doppler US in pediatric liver transplant patients illustrates normal findings and common vascular complications, including examples after surgical correction, in the perioperative period.

Hepatic artery reconstruction preserving the pancreaticoduodenal arcade in pediatric liver transplantation with celiac axis compression syndrome: report of a case

CACS is rare, although it has been reported to be a potential risk factor for hepatic artery thrombosis following LT. We herein present the case of a 14-yr-old male with stenosis of the origin of the celiac trunk. Preoperative CT and color ultrasonography showed narrowing of the proximal celiac artery. The patient underwent DDLT with standard arterial reconstruction without dividing the gastroduodenal artery. His postoperative course was uneventful, with an excellent hepatic artery flow on Doppler ultrasonography. Applying a meticulous preoperative evaluation and the appropriate surgical technique is crucial in patients with CACS.

Intraoperative assessment of reconstructed vessels in living-donor liver transplantation, using a novel fluorescence imaging technique

BACKGROUND/PURPOSE

In living-donor liver transplantation (LDLT), hepatic arterial thrombosis and portal venous thrombosis are critical problems that can result in graft loss. Only intraoperative Doppler ultrasound (IDUS) is able to evaluate blood flow in the reconstructed vessels. The aim of this study was to evaluate the utility of a newly developed fluorescence imaging technique using indocyanine green (ICG) for visualizing reconstructed vessels.

METHODS

In three patients who had undergone LDLT, IDUS was performed after reconstruction of the portal vein and hepatic artery. Fluorescence images were then recorded, using a SPY system (Novadeq Technologies), which employs ICG as a fluorescent imaging medium activated by light. The ICG (3.75 mg) was injected intravenously, then, 10 s later, the images were recorded for 30 s (first photographic recording). Two minutes later, the same procedure was repeated (second photographic recording), and 40 min later, images were obtained without injection of ICG (third photographic recording).

RESULTS

After portal venous reconstruction, IDUS demonstrated a nonphasic and continuous waveform, with a mean velocity of 52.1 cm/s and a mean portal blood flow volume of 69.5 ml/s per kg. After hepatic arterial reconstruction, a pulsatile waveform with a mean peak systolic velocity of 52.4 cm/s and a mean resistance index of 0.76 was obtained. The first photographic recording clearly visualized the blood flow in the reconstructed hepatic artery, without kinking or stenosis, in all three patients. The second photographic recording visualized the flow in the portal vein without stenosis, kinking, or stagnation. The third photographic recording demonstrated the excretion of ICG into bile, thus confirming bile production by the grafts.

CONCLUSIONS

Fluorescence imaging can clearly visualize the reconstructed hepatic artery and portal vein and demonstrate the production of bile by a transplanted liver graft. A combination of IDUS and the new system can guarantee the patency of the reconstructed vessels.

The Significance of Hepatic Vein Outflow Volume in Hepatic Outflow Insufficiency of Living Right Liver Graft Evaluated by Doppler Ultrasound

The color Doppler ultrasound has been used to evaluate hepatic vein (HV) outflow insufficiency based on flow velocity and waveforms. In our experience, some cases with flat waveforms are clinically asymptomatic. The parameters of HV flow velocity and waveforms are not always correlated with clinical problems. So, we proposed that total HV flow volume (HVFV) may be a more reliable index. From August 2001 to July 2003, 31 cases among 48 adult-to-adult living related transplants of a right liver graft had one HV anastomosis. HV velocity, waveforms, and HVFV were compared both before and after transplantation. We set the minimal HVFV ratio at 80% based on the original HVFV before graft retrieval. There was no significant difference in HVFV before liver graft retrieval between the 2 groups, but there was a significant change after transplantation. There were no cases of HV insufficiency among group A patients (>80%), whose HVFV ranged from 397 to 1181 mL/min with ratios from 75% to 180% (mean 115%). In group B, there were 4 complicated cases with prolonged severe ascites (<80%) with HVFV ratios from 56% to 76% (mean 66%). Fisher exact test showed a great significance (P < .001). Thus the preliminary criteria of 80% minimal HVFV ratio allows detection of HV insufficiency for further interventional management.

Hepatic venous stenosis in partial liver graft transplantation detected by color Doppler ultrasound before and after radiological interventional management

Hepatic outflow insufficiency remains one of the major complications causing postoperative graft failure especially among partial liver graft transplantations (PLT) including living donor liver transplantation (LDLT), reduced size liver transplantation (RLT), and split liver transplantation (SLT). These procedures are different from the whole liver graft transplantations (OLT), which include multiple vascular anastomoses. Color Doppler ultrasound (CDUS) was used to evaluate the hepatic venous outflow from grafts before and after radiological interventional management and to document treatment effects. From June 1994 to March 2003, our 136 cases of PLTs included 131 LDLTs, two RLTs, and three SLTs. Seven cases (six children and one adult) showed postoperative hepatic vein outflow obstruction and persistent massive ascites, as detected by color Doppler ultrasound (CDUS) and confirmed by interventional angiography. The CDUS showed a monophasic flat waveform with a relatively low hepatic vein average peak velocity (Va) in all cases (mean 11 cm/s). Successful interventional procedures included balloon dilatation in three cases and metallic stent replacement in four cases. CDUS was used with guidance during the procedure to confirm restoration of normal hepatic vein flow with a multiphasic waveform and an objective increase of average flow velocity (high to average 66 cm/s). Ascites disappeared dramatically after the procedure. In conclusion CDUS is the prime modality to diagnose and document a treatment response.