Quantitative portal vein velocity of liver cancer patients with transcatheter arterial chemoembolization on angiography

Retrograde portal vein flow and transarterial chemoembolization in patients with hepatocellular carcinoma - a case-control study

BACKGROUND AND AIMS

Transarterial chemoembolization (TACE) is the most common treatment for hepatocellular carcinoma (HCC). In case of portal vein (PV) flow diversion, outcome may be compromised due to a decompensation of hepatic perfusion following arterial embolization. The aim of this study was to determine whether TACE in patients with retrograde PV flow results in a stronger deterioration of liver function and a poorer survival compared to patients with orthograde PV flow.

METHODS

A database of 606 patients treated with TACE between 2000 and 2015 at Hannover Medical School was screened for Doppler ultrasound (US) findings on PV flow prior to TACE. A total of 407 patients were identified, among which 32 patients had retrograde PV flow.

RESULTS

Patients with retrograde PV flow had significantly more often liver cirrhosis with advanced hepatic dysfunction (93.5% vs. 72.7%, p < .05). Median overall survival (OS) was 12 and 19 months in patients with retro- and orthograde PV flow, respectively (HR 1.27, p > .05). Patients with retrograde PV flow showed a trend for a shorter OS when matched for cirrhosis (12 vs. 21months, HR 1.51), Child-Pugh score/albumin-bilirubin grade (12 vs. 15 months). There was no difference in the deterioration of liver function after repeated treatments between both groups as assessed by increase of CP points and ALBI grade.

CONCLUSIONS

Retrograde PV flow alone was not a significant prognostic marker, but patients with retrograde PV flow and advanced liver cirrhosis treated with TACE had a very short survival. Assessment of PV flow prior TACE may be helpful in borderline cases considered for TACE.

Quantitative analysis of digital subtraction angiography using optical flow method on occlusive cerebrovascular disease

BACKGROUND AND PURPOSE

Traditional digital subtraction angiography (DSA) provides detailed spatial resolution in the treatment of cerebrovascular disease. However, the available temporal information is often underutilized. The purpose of this study is to use deformable image registration with DSA to quantify the hemodynamic improvement of intracranial vessels after carotid stenting.

MATERIALS AND METHODS

Eighteen patients with carotid stenosis (greater than 70% degree by NASCET criteria) were treated using percutaneous transluminal angioplasty with stents. Carotid angiograms of the anterior-posterior and lateral views were acquired before and after the treatment. The arterial and venous phases of each single acquisition were classified according to the first arrival time of contrast in the distal middle cerebral artery and the superior sagittal sinus, respectively. The optical flow method was subsequently applied to determine the blood flow velocity in intracranial vessels. Blood flow velocity comparisons were performed to determine the therapeutic effects of blood flow restoration.

RESULTS

The pixel-by-pixel blood flow velocity was estimated using the optical flow method. A color scale was used in the visualization and estimation of the blood flow velocity in the vascular bed. The improvements of blood flow velocity in both the arterial and the venous phases were significant (p<0.05). The changes with contrast agent motion were more easily observed in the arterial phase compared with the venous phases.

CONCLUSION

Quantitative digital subtraction angiography provides reliable blood flow velocity measurements, which facilitates pretherapeutic evaluation and a reliable follow-up analysis method for the evaluation of occlusive vascular disorder treatment in the head and neck regions.

Quantification of blood flow in internal cerebral artery by optical flow method on digital subtraction angiography in comparison with time-of-flight magnetic resonance angiography

Objective

This study compared data on the blood flow velocity in the internal carotid artery, which was obtained using the optical flow method (OFM) with digital subtraction angiography (DSA) and the time-of-flight (TOF) technique using magnetic resonance angiography (MRA).

Materials and Methods

Images were obtained from 12 cerebrovascular patients who underwent both brain DSA and MRA imaging. The OFM was applied on the DSA images to determine the average blood flow velocity. The calculated results were compared with the values obtained from the TOF-MRA data. A linear fit was performed on the data and Bland-Altman plots were analyzed.

Results

The blood flow velocity was closely associated with vascular diseases. Color-coding of the OFM measurements were superimposed on to the DSA images, which quantitatively illustrated the relative flow in the vessels. The average blood flow velocity was calculated using OFM and DSA, which demonstrated a high correlation with the MRA measurements in the anterior-posterior (AP) view (R = 0.71). In contrast, the average blood flow velocity was low in the lateral view (R = 0.28). The consistency between the high and low blood velocity in the AP view was better compared to the lateral view. The blood flow velocity distribution in the AP view was statistically closer to the MRA measurement compared to the lateral view.

Conclusions

This study evaluated the correlation of blood flow measured using DSA and TOF-MRA in a small heterogeneous group of patients with cerebrovascular lesions. OFM with DSA imaging reveals hemodynamic information and TOF-MRA.