Accurate and rapid identification of feeding arteries with multidetector-row angiography-assisted computed tomography for transarterial chemoembolization for hepatocellular carcinoma

Preliminary phantom study of four-dimensional computed tomographic angiography for renal artery mapping: Low-tube voltage and low-contrast volume imaging with deep learning-based reconstruction

INTRODUCTION

A hybrid angio-CT system with 320-row detectors and deep learning-based reconstruction (DLR), provides additional imaging via 4D-CT angiography (CTA), potentially shortening procedure time and reducing DSA acquisitions, contrast media, and radiation dose. This study evaluates the feasibility of low-tube voltage 4D-CTA with low-contrast volume and DLR for selective renal artery embolization using a vessel phantom.

METHODS

A custom-made phantom simulating contrast-enhanced vessels filled with contrast medium was scanned. The study assessed image quality under varying image noise and vessel contrast. Quantitative analysis included peak contrast-to-noise ratio (pCNR) and image noise. Qualitative assessment was performed by seven radiologists using a 4-point scale; each radiologist independently recorded their evaluations on an assessment sheet.

RESULTS

A pCNR of approximately 15.0 was identified as the threshold for acceptable image quality. The pCNR decreased as the noise index increased (by 25-75 % when comparing a noise index of 30-70 HU).Vessels with a CT value of 500 Hounsfield units (HU) achieved sufficient image quality with a noise index of 50 HU. Dose reduction was substantial compared to traditional DSA, with effective radiation dose remaining within acceptable clinical levels.

CONCLUSION

4D-CTA, combined with DLR, demonstrated the potential to reduce radiation and contrast agent usage while preserving diagnostic quality for renal artery angiography. Further clinical validation is required to confirm these findings in clinical settings.

IMPLICATIONS FOR PRACTICE

4D-CTA with low-tube voltage and deep learning-based reconstruction (DLR) can reduce radiation and contrast use while maintaining image quality. This approach might improve safety, particularly in patients with renal impairment, and serve as a viable alternative to conventional DSA for selective renal artery embolization.

Low-dose Ultra-high-resolution Photon-Counting Detector CT for Visceral Artery CT Angiography: A Preliminary Study

RATIONALE AND OBJECTIVES

To validate the image quality of low-dose ultra-high-resolution (UHR) scanning mode of photon-counting detector CT (PCD-CT) for visceral artery computed tomography angiography (CTA).

MATERIAL AND METHODS

We prospectively enrolled 57 patients each in the full dose (FD) and low-dose (LD) protocols, respectively, to undergo abdominal CT scans using the UHR mode on a PCD-CT system (NAEOTOM Alpha), between April 2023 and September 2023. Both the FD data and LD data were then reconstructed into two series of images: (a) 0.2 mm slice thickness, reconstruction kernel Bv48, quantum iterative reconstruction (QIR) 4; (b)1 mm slice thickness, Bv40, QIR 3. The signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of seven arteries were objectively measured. The image noise, vessel sharpness, overall quality, and visibility of nine arteries were subjectively assessed by three radiologists.

RESULTS

The SNRs and CNRs of 0.2 mm reconstruction set was inferior to that of 1 mm reconstruction set (p < 0.001 for all the arteries and noise), however, the image quality of 0.2 mm reconstruction set was higher than that of 1 mm reconstruction set in qualitative evaluation especially for tiny arteries in Volume-rendered (VR) image (p < 0.001). The SNRs and CNRs were not significantly higher for FD group than LD group on the same slice thickness except for SNRs of common hepatic artery, splenic artery and bilateral renal arteries in 0.2 mm reconstruction set. In the comparison on image quality between normal weight and overweight patients within the same reconstruction set, the results showed that low-dose scan did not significantly impact the image quality in overweight patients. The ratings of visibility of nine visceral arteries were not significantly different among FD and LD at the same thickness reconstruction set except for superior mesenteric artery (p = 0.002 and 0.007 for 0.2 mm and 1 mm reconstruction set in axial image; p = 0.002 and 0.007 for 0.2 mm and 1 mm reconstruction set in coronal image, respectively) and left gastric artery (p = 0.002 and p < 0.001 for 0.2 mm and 1 mm reconstruction set in VR image, respectively).

CONCLUSION

The low-dose UHR scanning mode of PCD-CT has proven to be adequate for the clinical evaluation of visceral arteries. Utilizing a reconstruction with a slice thickness of 0.2 mm could enhance arterial depiction, particularly for small vessels.

Feasibility Study of Transarterial Chemotherapy Followed by Chemoembolization for Recurrent Breast Cancer

PURPOSE

To assess the treatment response to transarterial chemotherapy followed by chemoembolization for locally recurrent breast cancer.

MATERIALS AND METHODS

Thirty-nine women with locally recurrent breast cancer after standard therapy underwent selective intra-arterial chemotherapy followed by embolization using drug-eluting microspheres for locally recurrent tumors and axillary lymph node metastases. Tumor response and toxicity were assessed by the Response Evaluation Criteria in Solid Tumors (RECIST) and Common Terminology Criteria for Adverse Events (CTCAE), and survival was evaluated by the Kaplan‒Meier method.

RESULTS

The local responses of breast tumors at 3 and 6 months were as follows: complete response, 5.1% and 7.2%; partial response, 35.9% and 67.8%; stable disease, 59.0% and 21.4%; and progressive disease, 0.0% and 3.6%, respectively. All adverse events were mild and did not require treatment. The median overall survival (OS) was 46.5 months, and the OS rates for 1 and 2 years were 81.4% and 69.2%, respectively. The size of recurrent tumors and axillary lymph node metastases did not impact prognosis, but both liver and bone metastases adversely affected survival.

CONCLUSION

Transarterial chemotherapy followed by chemoembolization may provide a favorable tumor response in patients with locally recurrent breast cancer in whom conventional therapy has failed.

Number of computed tomography scanners and regional disparities based on population and medical resources in Japan

This study aimed to discover the associations between the number of computed tomography (CT) scanners and the population, as well as number of medical resources to identify regional disparities in Japan. The number of CT scanners was tabulated for each detector row of CT scanners for hospitals and clinics in each prefecture. The number of CT scanners, patients, medical doctors, radiological technologists, facilities, and beds per 100,000 population was compared. Additionally, the number of hospitals with ≥ 200 beds and multidetector-row CT scanners with ≥ 64 rows were tabulated, and their ratios were calculated. Medical institutions in Japan have installed 14,595 scanners. CT scanners per 100,000 population were the highest in Kochi Prefecture, although the number of CT scanners in hospitals was the highest in Tokyo Prefecture. Multivariate analysis revealed the number of radiological technologists (β coefficient: 0.49; P = 0.03), facilities (β coefficient: 0.12; P < 0.01) and beds (β coefficient: 0.46; P < 0.01) as independent factors for the number of CT scanners. Prefectures with a high proportion of hospitals with ≥ 200 beds also had a relatively high proportion of CT scanners with ≥ 64 rows (P < 0.01). Our survey revealed an association between regional disparities in the number of CT scanners in Japan, the population, and number of medical resources. A positive correlation was found between hospital size and number of CT scanners with ≥ 64 rows.

Efficacy of adjuvant TACE on the prognosis of patients with HCC after hepatectomy: a multicenter propensity score matching from China

BACKGROUND

The survival benefit of adjuvant transarterial chemoembolization (TACE) in patients with hepatectomy for hepatocellular carcinoma (HCC) after hepatectomy remains controversial. We aimed to investigate the survival efficacy of adjuvant TACE after hepatectomy for HCC.

METHODS

1491 patients with HCC who underwent hepatectomy between January 2018 and September 2021 at four medical centers in China were retrospectively analyzed, including 782 patients who received adjuvant TACE and 709 patients who did not receive adjuvant TACE. Propensity score matching (PSM) (1:1) was performed to minimize selection bias, which balanced the clinical characteristics of the two groups.

RESULTS

A total of 1254 patients were enrolled after PSM, including 627 patients who received adjuvant TACE and 627 patients who did not receive adjuvant TACE. Patients who received adjuvant TACE had higher disease-free survival (DFS, 1- ,2-, and 3-year: 78%-68%-62% vs. 69%-57%-50%, p < 0.001) and overall survival (OS, 1- ,2-, and 3-year: 96%-88%-80% vs. 90%-77%-66%, p < 0.001) than those who did not receive adjuvant TACE (Median DFS was 39 months). Among the different levels of risk factors affecting prognosis [AFP, Lymphocyte-to-monocyte ratio, Maximum tumor diameter, Number of tumors, Child-Pugh classification, Liver cirrhosis, Vascular invasion (imaging), Microvascular invasion, Satellite nodules, Differentiation, Chinese liver cancer stage II-IIIa], the majority of patients who received adjuvant TACE had higher DFS or OS than those who did not receive adjuvant TACE. More patients who received adjuvant TACE accepted subsequent antitumor therapy such as liver transplantation, re-hepatectomy and local ablation after tumor recurrence, while more patients who did not receive adjuvant TACE accepted subsequent antitumor therapy with TACE after tumor recurrence (All p < 0.05).

CONCLUSIONS

Adjuvant TACE may be a potential way to monitor early tumor recurrence and improve postoperative survival in patients with HCC.

Safety, feasibility, and comfort of hepatic angiography and transarterial intervention with radial access for hepatocellular carcinoma

Background and Aim

Hepatic angiography procedures such as transarterial chemoembolization (TACE) are essential procedures for managing patients with hepatocellular carcinoma (HCC), and are usually performed with femoral access. However, femoral access causes patient discomfort and may be associated with the risk of hematoma or pseudoaneurysm at puncture site. We evaluated the safety, feasibility, and patient comfort of hepatic angiography procedures performed with radial access.

Methods

In this single‐institution, retrospective, time‐frame study, a total of 206 patients who underwent hepatic angiography procedures with radial access, which were first used on October 2017 at our institution, were compared with 240 patients who underwent the same procedures with femoral access before this period. Several measures were assessed, including procedure time and safety. In addition, a questionnaire was used to compare the access types regarding procedure‐associated discomfort.

Results

Hepatic angiography procedures performed with radial access, including TACE, were completed in all patients without complications. The procedure time was comparable between radial access and femoral access. Most patients preferred radial to femoral access. Patients taking anticoagulants were able to complete the procedures without discontinuing these drugs.

Conclusions

Hepatic angiography procedures with radial access resulted in less discomfort than those with femoral access, and the two approaches showed similar feasibility and safety. Radial access can be introduced as a routine technique for hepatic angiography procedures.

Radiation Exposure During Transarterial Chemoembolization: Angio-CT Versus Cone-Beam CT

INTRODUCTION

Cone-beam computed tomography (CBCT) has been developed to improve reliability of many interventional radiology (IR) procedures performed with Angio system, such as transarterial chemoembolization (TACE). Angio-CT has emerged as a new imaging technology that combines a CT scanner with an Angio system in the same IR suite. The purpose of our study was to compare Angio system with CBCT capability and Angio-CT in terms of patient radiation exposure during TACE procedures.

MATERIALS AND METHODS

Consecutive TACE procedures performed between January 2016 and September 2017 with the two imaging modalities (Artis Zeego defining the CBCT group and Infinix-i 4D-CT defining the Angio-CT group) were reviewed. TACE and patient's characteristics and patient radiation exposure parameters were collected. Dose-area products (DAP) and dose-length products (DLP) were converted into effective doses (ED) using conversion factors. Accuracy of tumor targeting and response was retrospectively assessed.

RESULTS

A total of 114 TACE procedures in 96 patients were included with 57 procedures in each group. The total ED in the Angio-CT group was 2.5 times lower than that in the CBCT group (median 15.4 vs. 39.2 mSv, p < 0.001). Both 2D ED and 3D ED were lower in the Angio-CT group than in the CBCT group (5.1 vs. 20 mSv, p < 0.001, and 7.4 vs. 17.9 mSv, p < 0.001, respectively). There was no significant difference neither in terms of classes of tumor targeting (p = 0.509) nor in terms of classes of tumor response (p = 0.070) between both groups.

CONCLUSION

Angio-CT provides significant decrease in patient effective dose during TACE procedures compared to Angio system with CBCT.

Discrepant imaging findings of portal vein thrombosis with dynamic computed tomography and computed tomography during arterial portography in hepatocellular carcinoma: possible cause leading to inappropriate treatment selection

We encountered a patient with hepatocellular carcinoma who had discrepant imaging findings on portal vein thrombosis with portal phase dynamic computed tomography (CT) and CT during arterial portography (CTAP). CTAP, via the superior mesenteric artery and via the splenic artery, both showed a portal perfusion defect in the right hepatic lobe, indicating portal vein thrombosis in the main trunk of the right portal vein. Portal phase dynamic CT clearly depicted portal perfusion of the same hepatic area. Transarterial chemoembolization was successfully performed, but it was associated with severe liver injury. Clinicians should be cautious about this possible discrepancy based on imaging technique. The inaccurate evaluation of portal vein thrombosis may result in inappropriate treatment selection, which can worsen patient prognosis.