Dual-energy CT virtual noncalcium technique: detecting posttraumatic bone marrow lesions--feasibility study

Area of Science:

• Radiology
• Medical Imaging
• Orthopedics

Background:

• Traumatic bone marrow injuries, such as bone bruises, are common in acute knee trauma.
• Magnetic resonance (MR) imaging is the current standard for detecting bone bruises, but computed tomography (CT) is more widely available.
• Dual-energy (DE) CT offers potential for improved tissue characterization compared to conventional CT.

Purpose of the Study:

• To evaluate the efficacy of a dual-energy (DE) computed tomographic (CT) virtual noncalcium technique for assessing traumatized bone marrow.
• To determine if DE CT virtual noncalcium imaging can detect posttraumatic bone bruises in the knee.

Main Methods:

• Prospective study involving 21 patients with acute knee trauma who underwent DE CT and MR imaging.
• A software application was used to virtually subtract calcium from DE CT images.
• Two radiologists rated bone bruises on a four-point scale and recorded CT numbers in specific regions, with MR imaging serving as the reference standard.

Main Results:

• After artifact exclusion, 59 bone bruises were identified in 236 regions by MR imaging.
• Areas under the curve for visual rating ranged from 0.886 to 0.974, and for CT numbers, they ranged from 0.922 to 0.974.
• Sensitivities for detecting bone bruises were 86.4% for both observers, with specificities of 94.4% and 95.5%.

Conclusions:

• The DE CT virtual noncalcium technique successfully subtracts calcium from cancellous bone.
• This technique allows for bone marrow assessment and shows potential for detecting posttraumatic bone bruises of the knee using CT.