Dual-Energy CT in Hemorrhagic Progression of Cerebral Contusion: Overestimation of Hematoma Volumes on Standard 120-kV Images and Rectification with Virtual High-Energy Monochromatic Images after Contrast-Enhanced Whole-Body Imaging

Abstract

The 120-kV images, which are comparable with single-energy CT images, significantly overestimated the hematoma volumes, hence the rate of hemorrhagic progression of contusions, after contrast-enhanced whole-body CT. Hence, follow-up of hemorrhagic contusions should be performed on dual-energy CT, and 190-keV images should be used for the assessment of hematoma volumes.

Is Dual-Energy CT Ready for Prime Time in Traumatic Brain Injury?

“…When it comes to different types of hemorrhage detection in patients with TBI, thin-section virtual high-energy monochromatic images at 190 keV created with DE CT were found to be superior to standard CT images in the detection of subdural hematomas, supratentorial contusions, and epidural hematomas, while subarachnoid bleeds were best depicted with standard 120-keV images (9). More directly related to the current work, the same team has shown that when follow-up of hemorrhagic contusions is performed with unenhanced CT after contrast material has been administered for polytrauma wholebody CT, virtual unenhanced images created with DE CT more accurately depicted contusion progression because conventional CT results in overestimation of hematoma volume secondary to contrast material leakage (10). While these prior studies have shown that DE CT can be useful to compensate for confounding contrast material leakage artifacts observed in patients undergoing a contrast-enhanced polytrauma whole-body CT protocol, the present work is important in its suggestion that contrast material administration and DE CT may actually be advantageous as a biomarker of secondary injury mechanisms driving HPC.…”

Quantification of Iodine Leakage on Dual-Energy CT as a Marker of Blood-Brain Barrier Permeability in Traumatic Hemorrhagic Contusions: Prediction of Surgical Intervention for Intracranial Pressure Management

“…For measuring the iodine concentration in the contusion, DECT data from follow-up head CT studies were used with the modified Brain Hemorrhage application on the postprocessing workstation (syngo.via). 2 In patients with .1 follow-up head CT, measurements were also obtained from the second follow-up study to facilitate the calculation of the fractional rate of iodine washout from the contusions. Average iodine concentration was measured by drawing an ROI around each contusion.…”

“…Pseudohematoma is defined as enhancing penumbra caused by an iodine leak on follow-up 120-kV images. 2 The attenuation contribution of iodine tends to be negligible at 190 keV, therefore demonstrating attenuation only from the hematoma, allowing measurement of true hematoma volume. 2 Hence, with the availability of hematoma volume on 120 kV-(true hematoma þ enhancing penumbra) and true hematoma volume on 190-keV images, the pseudohematoma volume can be calculated as the following: Pseudohematoma Volume = (B -C), where B is the volume on 120-kV and C is volume on 190-keV images.…”

“…to increased intracranial pressure (ICP). [1][2][3] Vasogenic edema caused by BBB disruption in contusions is an important contributing factor for ICP elevation. 4 An uncontrolled increase in ICP is a poor prognostic factor in closed-head injuries.…”

“…15 The contrast bolus administered during the admission WBCT leaks into and is retained in the epicenter and penumbra of hemorrhagic contusion due to capillary fragmentation and BBB disruption. 2 Dual-energy CT (DECT) has proved helpful in differentiating and quantifying the iodine leakage from hemorrhages in cerebral infarctions, subdural spaces, and spontaneous hemorrhages. 2,16,17 Using both unenhanced admission and short-term follow-up head DECTs obtained after WBCT, we aimed to identify imaging variables and clinical parameters that correlate with surgical intervention for ICP management.…”