Combined multi-kernel head computed tomography images optimized for depicting both brain parenchyma and bone

Abstract

BACKGROUND: The hybrid convolution kernel technique for computed tomography (CT) is known to enable the depiction of an image set using different window settings. OBJECTIVE: Our purpose was to decrease the number of artifacts in the hybrid convolution kernel technique for head CT and to determine whether our improved combined multi-kernel head CT images enabled diagnosis as a substitute for both brain (low-pass kernel-reconstructed) and bone (high-pass kernel-reconstructed) images. METHODS: Forty-four patients with nondisplaced skull fractures were included. Our improved multi-kernel images were generated so that pixels of >100 Hounsfield unit in both brain and bone images were composed of CT values of bone images and other pixels were composed of CT values of brain images. Three radiologists compared the improved multi-kernel images with bone images. RESULTS: The improved multi-kernel images and brain images were identically displayed on the brain window settings. All three radiologists agreed that the improved multi-kernel images on the bone window settings were sufficient for diagnosing skull fractures in all patients. CONCLUSIONS: This improved multi-kernel technique has a simple algorithm and is practical for clinical use. Thus, simplified head CT examinations and fewer images that need to be stored can be expected.

Image Quality Required for the Diagnosis of Skull Fractures Using Head CT: A Comparison of Conventional and Improved Reconstruction Kernels

“…Though the quality of combined multikernel images for the diagnosis of skull fractures has been reported to be poorer than the quality of bone images, 3 we observed no significant differences in the present study. The quality of combined multikernel images has also been reported to be clearly better than the quality of brain images when bone window settings are used and equal to the quality of brain images when brain window settings are used.…”

“…The quality of combined multikernel images has also been reported to be clearly better than the quality of brain images when bone window settings are used and equal to the quality of brain images when brain window settings are used. 3 Conversely, the disadvantages of conventional 2D bone images and the efficacy of additional 3D CT image reconstruction have been reported. 2,11 Therefore, we recommend combined multi-kernel image and 3D image reconstruction for improved diagnostic performance for skull fractures and simplification of head CT examinations.…”

“…Combined multikernel head CT images were generated by combining the brain and bone images by using the threshold method with customized software developed by Microsoft Visual C# (Microsoft, Redmond, Washington). 3 A total of 4614 images (1538 images per kernel type, approximately 31 images per patient) were analyzed.…”

“…To resolve this issue, the usefulness of a combined multikernel technique that enables the evaluation of both brain and bone through a change in the window settings of an image set for the assessment of skull fractures has been reported. 3,4 The use of this technique not only decreases the number of stored images and simplifies head CT examinations, but also enables the assessment of bone tissue in all cases. However, the diagnostic performance of this technique has not been sufficiently investigated.…”

A novel multiple-windows blending of CT images in red-green-blue (RGB) color space: Phantoms study

“…Similar results were reported by Sabouri et al [15]. These examples indicate that the use of multiple windows may improve the diagnostic accuracy of a CT scan [14][15][16][17]. However, interpretation using multiple windows takes additional time and more effort from the radiologists.…”