Revista de investigación del cerebro

Brain Tissue Contrast: Ct Versus Mri

Abstract

Ramya Balakrishnan

 Medical images aim to provide adequate structural information to diagnose abnormal conditions and aid in therapeutic procedures. Computed tomography (CT) and Magnetic Resonance Imaging (MRI) are widely used imaging tools for diagnostic purposes and clinical research. These imaging modalities are complementary to each other. However, image quality of CT and MRI greatly varies. For instance, same level of visibility cannot be achieved for white matter displayed on CT and MRI. In 1969, Kurt Rossmann who was a pioneer in modern x-ray imaging research described image quality as that attribute of that image which affects the certainty with which diagnostically useful detail can be detected visually by the radiologist’ [1]. A high-quality image can represent the anatomy of the brain clearly. Quality of an image can be described in terms of contrast, spatial resolution, noise, and artefacts [2]. Contrast is defined as ‘the separation between the darkest and brightest areas of the image’ [3]. In this article, brain tissue contrast exhibited by CT and MRI is discussed in detail. It is important to evaluate the level of contrast provided by CT and MRI for soft and hard tissues of brain, and how human eye perceive these images. An understanding about these concepts helps in choosing the right imaging modality to observe a particular brain tissue.

 Medical images aim to provide adequate structural information to diagnose abnormal conditions and aid in therapeutic procedures. Computed tomography (CT) and Magnetic Resonance Imaging (MRI) are widely used imaging tools for diagnostic purposes and clinical research. These imaging modalities are complementary to each other. However, image quality of CT and MRI greatly varies. For instance, same level of visibility cannot be achieved for white matter displayed on CT and MRI. In 1969, Kurt Rossmann who was a pioneer in modern x-ray imaging research described image quality as that attribute of that image which affects the certainty with which diagnostically useful detail can be detected visually by the radiologist’ [1]. A high-quality image can represent the anatomy of the brain clearly. Quality of an image can be described in terms of contrast, spatial resolution, noise, and artefacts [2]. Contrast is defined as ‘the separation between the darkest and brightest areas of the image’ [3]. In this article, brain tissue contrast exhibited by CT and MRI is discussed in detail. It is important to evaluate the level of contrast provided by CT and MRI for soft and hard tissues of brain, and how human eye perceive these images. An understanding about these concepts helps in choosing the right imaging modality to observe a particular brain tissue.