Improving cone-beam computed tomography image quality for transarterial therapy of liver malignancies: Evaluation of
Abdul Rehman Mustafa1, Adham Khalil1, Arun Kamireddy1
1Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, United States.
Objectives:
The objectives of the study are to compare the effect on image quality of a motion artifact correction algorithm (CAVAREC) alone versus in combination with an automated bone removal algorithm (ZIBOS) for motion-degraded intraprocedural liver cone-beam computed tomography (CBCT) images.
Material And Methods:
In this retrospective, two-center, Institutional Review Board (IRB)-approved study, 48 CBCTs from 41 patients were included. Inclusion criteria were (a) age ≥18; (b) liver CBCT with contrast injected at the main, right, or left hepatic artery; and (c) CBCT motion-degraded. Exclusion criteria were (a) no visible tumor and (b) CBCT not capturing the entire liver. The mean (standard deviation [SD]) age was 64 (7) years, 81% male. 65% had hepatocellular carcinoma and 35% metastatic cancer. 69% CBCTs were from transarterial radioembolization (TARE) mapping, 25% transarterial chemoembolization, and 6% TARE treatment. Mean (SD) maximum tumor diameter was 4.6 (2.7) cm. CBCT images were processed with CAVAREC (prototype, Siemens Healthineers AG, Forchheim, Germany) and CAVAREC + ZIBOS (work in progress, Comprehenso, Hannover, Germany). Using CoroEval, sharpness for two segmental arteries per case was obtained quantitatively. Three blinded interventional radiologists independently evaluated overall image quality on a 0-100 scale and large vessels, small vessels, vessel sharpness, tumor feeders, tumor blush, and streak artifacts on a -50 to +50 scale relative to uncorrected images. Results were analyzed with paired t-tests and Wilcoxon signed-rank tests, adjusting P-values with the Benjamini-Hochberg procedure.
Results:
On quantitative assessment, mean (SD) sharpness for uncorrected, CAVAREC, and CAVAREC + ZIBOS (C+Z) images was 0.281 (0.04), 0.287 (0.04), and 0.284 (0.04), respectively, P = 0.02 for uncorrected versus CAVAREC and P > 0.05 for other comparisons. On qualitative assessment, mean (SD) overall quality for uncorrected, CAVAREC, and C+Z images was 45 (14), 53 (16), and 53 (17), respectively, P < 0.001 for both uncorrected versus CAVAREC and uncorrected versus C+Z and P = 0.06 for CAVAREC versus C+Z. The mean preference for both CAVAREC and C+Z compared to uncorrected images for all parameters ranged from +4.3 to +9.5, P < 0.001, except tumor blush which was +1.6 for CAVAREC and +0.9 for C+Z, P > 0.05. CAVAREC versus C+Z was not significant for any parameter.
Conclusion:
Motion artifact correction of liver CBCT images using CAVAREC improves image quality significantly. According to observer studies, integrating the automated bone segmentation algorithm ZIBOS with CAVAREC does not degrade image quality.
