also known as Cavernous hemangioma.
First described by Luschka in 1854, Cavernous malformation (CCM)s are benign, low-flow vascular lesions with thin elastic endothelial walls that lack adventitial smooth muscle and frequently present with little intervening brain parenchyma.
Also called cavernous angioma, or cavernoma (often when referring to presence in the brain), is a type of hemangioma, where a collection of dilated blood vessels form a tumor. Because of this malformation, blood flow through the cavities, or caverns, is slow. Additionally, the cells that form the vessels do not form the necessary junctions with surrounding cells and the structural support from the smooth muscle is hindered causing leakage into the surrounding tissue. It is the leakage of blood, known as a hemorrhage from these vessels that causes a variety of symptoms known to be associated with this disease.
Cavernous malformations (cavernous angiomas, cavernomas, cavernous hemangiomas) are well-defined, grossly visible lesions that may reach a significant size. They are composed of a compact mass of sinusoidal-type vessels immediately in apposition to each other without any recognizable intervening neural parenchyma.
Radiation-induced cavernous haemangiomas (RICHs) are a known late complication of radiation exposure, especially in young children.
Occurring in familial autosomal dominantly inherited or isolated forms. Once CCM are diagnosed by magnetic resonance imaging, the indication for genetic testing requires either a positive family history of cavernous lesions or clinical symptoms such as chronic headaches, epilepsy, neurological deficits, and hemorrhagic stroke or the occurrence of multiple lesions in an isolated case. Following these inclusion criteria, the mutation detection rates in a consecutive series of 105 probands were 87% for familial and 57% for isolated cases. Thirty-one novel mutations were identified with a slight shift towards proportionally more CCM3 mutations carriers than previously published (CCM1: 60%, CCM2: 18%, CCM3: 22%). In-frame deletions and exonic missense variants requiring functional analyses to establish their pathogenicity were rare: An in-frame deletion within the C-terminal FERM domain of CCM1 resulted in decreased protein expression and impaired binding to the transmembrane protein heart of glass (HEG1). Notably, 20% of index cases carrying a CCM mutation were below age 10 and 33% below age 18 when referred for genetic testing. Since fulminant disease courses during the first years of life were observed in CCM1 and CCM3 mutation carriers, predictive testing of minor siblings became an issue 8).
Microscopically, cavernous angiomas consist of sclerotic, variably calcified compact vessels in a honeycomb pattern.
Unlike telangiectasis and arteriovenous malformation these lesions do not contain interstitial parenchyma.