Role of contrast-enhanced ultrasound in the evaluation of post-liver transplant vasculature.

Liver transplantation is a frequently used treatment for patients with end-stage liver disease and ultrasound is often the first-line imaging technique for detection of vascular complications after liver transplant. Although colour Doppler ultrasound is a good screening method for evaluation of post-liver transplant vasculature, it has limitations in evaluating small-calibre vessels and vessels in close proximity. Contrast-enhanced ultrasound (CEUS) has been proposed to overcome these limitations by improving visualisation of post-liver transplant vasculature and reducing the number of false-positive cases, which necessitate unnecessary additional investigations such as computed tomography or angiography. Liver transplant anatomy and the wide array of post-transplant imaging findings on colour Doppler have already been well described but literature on the use of CEUS and its image interpretation remain scarce. This review aims to discuss the indications for CEUS after liver transplant, to demonstrate CEUS technique and familiarise readers with the imaging appearances of post-transplant vascular complications on CEUS.

Role of Coronary Angiography in Pre-Liver Transplantation Cardiac Evaluation: Experience From an Asian Transplant Institution.

BACKGROUND: Liver transplant (LT) patients with significant coronary artery disease (CAD) have poorer outcomes. Pre-LT coronary angiography (CA) is associated with significant complications in cirrhotic patients. METHODS: This study aimed to identify predictors of abnormal CA in pre-LT cardiac assessment and to develop a predictive model to reduce unnecessary CA. From January 2006 to June 2013, 122 patients underwent CA based on the current institutional protocol. RESULTS: Forty-one (33.6%) patients had abnormal CA. Univariate analysis showed age ≥65 years (P = .001), cryptogenic cirrhosis (P = .046), cardiac comorbidities (P = .027), ischemic heart disease (IHD; P = .002), left ventricular hypertrophy (LVH; P = .004), hypertension (P = .002), diabetes mellitus (P = .017), dyslipidemia (P < .001), metabolic syndrome (P = .003), ≥2 CAD risk factors (P = .001), and high Framingham risk score (hard CAD risk, P = .018; cardiovascular disease: lipids, P = .002; body mass index, P < .001) to be significant predictors of abnormal CA. A predictive model was developed with the use of multivariable logistic regression and included diabetes, dyslipidemia, IHD, age ≥65 years, and LVH, achieving a specificity of 55.1% and sensitivity of 90.0%. This would reduce unnecessary CA by up to one-half in our study population (from 81 to 35) while maintaining a false negative rate of only 8.5%. CONCLUSIONS: Diabetes, dyslipidemia, IHD, age ≥65 years, and LVH appear to be predictors of abnormal CA in pre-LT patients. Our predictive model may help to better select patients for CA, although further validation is required.

Endoscopic ultrasonography for gastric cancer: does it influence treatment?

BACKGROUND: This study aimed to evaluate the utility and shortcomings of endoscopic ultrasound (EUS) in tumor node metastasis (TNM) staging of gastric cancer and its influence on treatment. METHODS: The series included 126 patients (65 men and 44 women) with gastric cancer who underwent EUS from July 1997 to June 2003 at the National University Hospital, Singapore. The final analysis included 109 patients ranging in age from 29 to 97 years (mean, 63.13 years). RESULTS: EUS staging for primary disease: Specimen histology was available for 102 of the 109 patients who underwent surgery. The accuracy was 79% for T1, 73.9% for T2, 85.7% for T3, and 72.7% for T4. The overall accuracy was 80.4%. EUS staging for nodes: The sensitivity of EUS for detecting nodal disease was 74.2% for N0, 78% for N1, 53.8% for N2, and 50% for N3. Overall, the N staging by EUS showed a sensitivity of 82.8%, a specificity of 74.2%, a positive predictive value of 85.4%, a negative predictive value of 70.2%, and an accuracy of 77.7%. Radical gastrectomy was proposed for 95 patients on the basis of the staging with EUS and computed tomography (CT) scan, and 87 patients (91.6%) underwent the surgery. Preoperative staging accurately predicted the operative strategy for 89% of the patients. No significant predictor for accuracy was achieved by performing a logistic regression analysis for the correct staging of T stage using EUS and adjusting for tumor location (middle part/distal third/whole stomach vs proximal/cardioesophageal) (p = 0.873), operator (p = 0.546), and subject's sequence (initial 50 vs last 50 cases) (p = 0.06). CONCLUSION: Ultrasound is the most accurate and reliable method for the preoperative staging of gastric carcinomas, and it is mandatory if a tailored therapeutic approach is planned according to stage.

Value of alpha-foetoprotein for screening of recurrence in hepatocellular carcinoma post resection.

INTRODUCTION: The aim of this study was to establish the value of alpha-foetoprotein (AFP) for the screening of recurrences in hepatocellular carcinoma (HCC) in patients who have undergone curative hepatic resection. METHODS: 72 HCC patients who had curative resection/liver transplant in 2000-2006 were monitored for recurrence by evaluating the three- or six-monthly AFP and computed tomography images. Patients without recurrence were followed up for a mean duration of 7.27 years. RESULTS: Out of the 72 patients, 34 (47.2%) suffered from HCC recurrence. 65.4% of recurrent cases had AFP values showing an upward trend. Patients with recurrence had higher AFP values than those without at last follow-up (119.45 µg/L vs. 3.1 µg/L, p < 0.001). AFP at recurrence was independent of gender, race, history of alcohol consumption and hepatitis C or cirrhosis status. Patient with hepatitis B or those with tumours larger than 5 cm had higher AFP values. The best cut-off AFP indicative of HCC recurrence was 5.45 µg/L (sensitivity 84.4%; specificity 77.1%). High preoperative AFP was associated with high AFP at recurrence (correlation coefficient 0.553, p = 0.01). CONCLUSION: AFP alone is an inadequate screening test for HCC recurrence since only about two-thirds of patients showed upward AFP trend on recurrence. Our study found a relatively low cut-off point for detection of recurrence (5.54 µg/L). Patients with high preoperative AFP tended to have high AFP on recurrence. Imaging is recommended for patients with AFP levels > 5.45 µg/L, especially when AFP shows a rising trend.