Objective: To assess the feasibility and efficiency of a perspective view technology (Fly Thru) for the detection of portal vein tumor thrombus (PVTT) in hepatocellular carcinoma (HCC) patients.
Methods: Fly Thru was performed in 79 HCC patients. The images were reviewed off-site for evaluation of the imaging quality and diagnosis. Pathology and/or contrast-enhanced CT was used as the reference standard for PVTT. The diagnostic quality of the images, presences of PVTT, and patency of the target vessels were recorded by two-dimensional ultrasound (2DUS) and Fly Thru image. The diagnostic performances of resident and staff radiologists were compared between 2DUS with or without off-line Fly Thru.
Results: Fly Thru was performed successfully in 43 of 79 patients (54.4%). The Fly Thru Imaging quality was good in 30/43 patients (69.8%), suboptimal but diagnostic in 10/43 (23.2%), and non-diagnostic in the remaining 3/43 (7.0%). PVTTs were detected in 31 patients according to the reference standard, with 8 in the main portal vein, 15 in the first branch, and 8 in the second branch of the portal vein. The agreement was good between conventional 2DUS and Fly Thru (κ = 0.783, p = 0.000). There was a significant association between the quality and the ability of Fly Thru in the detection of PVTTs (p = 0.001). The diagnostic performance for both readers between 2DUS with or without Fly Thru showed no statistically significant differences, except for the sensitivity for resident radiologist. The sensitivity of 2DUS (71.0%, 22/31) for resident radiologists was lower than that of Fly Thru as an adjunctive diagnostic tool (90.3%, 28/31) (p = 0.041).
Conclusion: Fly Thru is of diagnostic quality and can provide useful information for the detection of PVTT in HCC patients.