Capillary-Venous Abnormalities in Children

According to McCormick’s classification scheme, intracranial vascular malformations of the central nervous systems are originally categorized into four types: cavernous malformations, capillary telangiectasias, developmental venous anomalies (DVAs, formerly known as venous angiomas), and arteriovenous malformations (McCormick 1966). In this chapter, we will describe the former three vascular malformations. According to the classification of pediatric vascular malformation as outlined in the chapter on “▶ Pediatric Vascular Malformations” in this book, these vascular abnormalities can be regarded as focal diseases on the venous end of the spectrum of the arteriovenolymphatic tree. In the past, it was assumed that all these described malformations are congenital lesions. However, observation of multiplicity and coexistence of the lesions (Clatterbuck et al. 2001), as well as sporadic reports of the de novo formation of capillary telangiectasias and/or cavernomas with or without associated DVA (Abla et al. 2008), has suggested that these entities can be acquired or have multifactorial origins or even trigger each other. This appears to be especially true for the cavernomas as will be outlined in greater detail below. We will also try to show that the boundaries between some of these lesions are not clear-cut, with transitory forms existing, for example, between the capillary telangiectasias and the DVAs.