Usefulness of the advanced monoenergetic image reconstruction in dual-energy computed tomography for detecting the perforator vein of lower extremity varix

Abstract

Background Identification of the perforator vein is important for treating lower extremity varix. Purpose We evaluated the ability of 40-keV advanced monoenergetic images to depict the perforator vein in patients with lower extremity varix. Material and Methods Thirty-three patients aged 52–86 years were examined with contrast-enhanced dual-energy computed tomography (CT) and advanced virtual monoenergetic images (40 keV) were reconstructed. For evaluating enhancement of a lower extremity vein and the difference in CT number between the vein and muscle, we set the region of interest on the popliteal vein (PV). We also evaluated the ability of 100-kVp and 40-keV volume-rendering (VR) images to depict the perforator veins. Results The mean CT numbers of the PV at 100 kVp and 40 keV were 113 ± 16 and 321 ± 63 HU, respectively ( P < 0.01). In 40-keV transverse images of 33 patients, 84 of the perforator veins were detected. In those 84 veins, 70 (83%) were depicted and 14 (17%) were not depicted on VR images that were reconstructed from 40-keV transverse images. At 100 kVp, 10 (12%) of the perforator veins could be depicted in VR images because the muscles buried them or the PVs were blurred due to insufficient enhancement. Conclusion The advanced monoenergetic reconstruction technique is useful for evaluating the perforator vein in patients with lower extremity varix.

Usefulness of advanced monoenergetic reconstruction technique in dual-energy computed tomography for detecting bladder cancer

“…In low-keV images that are reconstructed using the virtual monoenergetic technique, contrast enhancement can be strengthened compared with usual CE-CT images, as shown in our and previous studies [ 13 ]. Using monoenergetic-image reconstruction, the BC–BW value of the 40-keV image was higher than that of the virtual-120-kVp image.…”

“…Monoenergetic images can be reconstructed using two different energies. Contrast of lower kilo electron volt (keV) images is stronger than that of usual low-kVp images such as 80-kVp images [ 13 ]. Therefore, we considered sensitivity of BC detection could be increased if low-keV image is used as routine CE-CT examination (100 s).…”