Multimodality Medical Image Fusion: Applications in Congenital Cardiology

Abstract

KEYWORDS• congenital cardiology • image fusion • image registration • medical image computing Image fusion: definition Image fusion consists of registering and visualizing different sets of images of a given object or scene. In medical disorders, pathology affects different tissues in a variable manner. These are best imaged in different modalities using diverse technologies. Image fusion helps to integrate all of the information and aids in accurate diagnosis and treatment. The implicit image fusion composed by the treating physician can be subjective and prone to error, which image fusion systems can help to mitigate. Medical image fusion is a very broad field covering aspects of computer vision, pattern recognition, machine learning and artificial intelligence in addition to image processing. Brief historyThe earliest mention of the word 'image fusion' in the clinical context was in 1992 by Swayne, who reported on computer-assisted fusion of single-photon emission computed tomographic (SPECT) and computed tomographic (CT) images in localizing inflammatory processes in 10 patients [1]. A combination of standard scaling, rotation, translation and stretching transformations were used to fuse images with anatomic and external landmarks. Stereotactic neurosurgery [2] was the next major application for image fusion, closely followed by oncology [3]. Rapid improvements in computers and their processing power led to increasing development and use of image fusion, particularly in imageguided surgery in a variety of medical specialties. The problems with software-based posthoc image fusion have led to the development of combined scanners, which acquire both anatomical and functional images during a single imaging session. This is achieved by fusing of technologies such as PET/CT scanner and PET/MRI scanner [4]. This also stimulated the development of co-location of complementary imaging modalities such