Hiroshi Tanaka1, Tsuyoshi Igami2, Yoshie Shimoyama3, Tomoki Ebata1, Yukihiro Yokoyama1, Kensaku Mori4,5, Masato Nagino1. 1. Division of Surgical Oncology, Department of Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan. 2. Division of Surgical Oncology, Department of Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, 466-8550, Japan. igami@med.nagoya-u.ac.jp. 3. Department of Pathology and Clinical Laboratories, Nagoya University Graduate School of Medicine, Nagoya, Japan. 4. Graduate School of Informatics, Nagoya University, Nagoya, Japan. 5. Information Strategy Office, Information and Communications, Nagoya University, Nagoya, Japan.
Abstract
PURPOSE: Perineural invasion (PN) is often found in perihilar cholangiocarcinoma. New procedure was developed to assess PN around the right hepatic artery (RHA) using dual-energy computed tomography (DECT). METHODS: Thirty patients with perihilar cholangiocarcinoma who underwent DECT before biliary drainage were retrospectively reviewed. Mask images, i.e., the periarterial layer (PAL) around the RHA and superior mesenteric artery (SMA), were made from late arterial phase DECT. The mean CT number of the PAL was measured. RESULTS: Twenty patients with PN around the RHA were classified into the PN (+) group. The remaining 10 patients without PN and other 26 patients with other diseases that are never accompanied with PN were classified into the PN (-) group. The PAL ratio (the CT number of the PAL around the RHA relative to that around the SMA) was calculated. Both the mean CT number of the PAL around the RHA and the PAL ratio were significantly higher in the PN (+) group than in the PN (-) group. According to an ROC analysis, the predictive ability of the PAL ratio was superior. Using the cutoff value of the PAL ratio 1.009, a diagnosis of PN around the RHA was made with approximately 75% accuracy. CONCLUSIONS: Assessment with CT number of the PAL reconstructed from DECT images is an easy and objective method to diagnose PN.
PURPOSE: Perineural invasion (PN) is often found in perihilar cholangiocarcinoma. New procedure was developed to assess PN around the right hepatic artery (RHA) using dual-energy computed tomography (DECT). METHODS: Thirty patients with perihilar cholangiocarcinoma who underwent DECT before biliary drainage were retrospectively reviewed. Mask images, i.e., the periarterial layer (PAL) around the RHA and superior mesenteric artery (SMA), were made from late arterial phase DECT. The mean CT number of the PAL was measured. RESULTS: Twenty patients with PN around the RHA were classified into the PN (+) group. The remaining 10 patients without PN and other 26 patients with other diseases that are never accompanied with PN were classified into the PN (-) group. The PAL ratio (the CT number of the PAL around the RHA relative to that around the SMA) was calculated. Both the mean CT number of the PAL around the RHA and the PAL ratio were significantly higher in the PN (+) group than in the PN (-) group. According to an ROC analysis, the predictive ability of the PAL ratio was superior. Using the cutoff value of the PAL ratio 1.009, a diagnosis of PN around the RHA was made with approximately 75% accuracy. CONCLUSIONS: Assessment with CT number of the PAL reconstructed from DECT images is an easy and objective method to diagnose PN.
Authors: Wolfgang M Thaiss; Alexander W Sauter; Malte Bongers; Marius Horger; Konstantin Nikolaou Journal: Eur J Radiol Date: 2015-06-06 Impact factor: 3.528