ABSTRACT
Recently, the concept of CAD has been expanded to the cerebral region. A screening system called the Brain Check-up is widely employed in Japan. A number of CAD schemes are being developed in Japan to assist radiologists in the early detection of cerebrovascular diseases at screening centers and hospitals (Arimura et al. 2004, Hayashi et al. 2003, Kobayashi et al. 2006, Uchiyama et al. 2005, 2007a, Yokoyama et al. 2007). Figure 15.1 shows the trend in leading causes of death in Japan. e number of cerebrovascular diseases has gradually decreased every year. However, it should be noted that the numbers of cases of subarachnoid hemorrhage (SAH) and cerebral infarction are on the increase. erefore, it is important to reduce the incidence of these conditions. In this chapter, CAD schemes developed at Gifu University (Fujita et al. 2008) and observer performance studies are presented, with reference to related works and with an emphasis on potential clinical applications in the future. Subjects for these CAD schemes included in the following sections are (1) detection of intracranial unruptured aneurysms in magnetic resonance angiography (MRA), (2) a new viewing technique for the detection of unruptured aneurysms, (3) detection of arterial occlusion in MRA, (4) detection of lacunar infarcts in T1-and T2-weighted images, and (5) classication of lacunar infarcts and enlarged Virchow-Robin spaces in T1-and T2-weighted images.
