Epidemiology of Cavernous Malformations in Children
Incidence and Prevalence
0.4–0.5% prevalence: Postmortem studies performed in the 1980s found that 0.37–0.5% of the population harbored cavernous malformations. Similar results were obtained by MRI examination with a prevalence of 0.4–0.5% (20, 40, 44, 54).
Mean age at presentation 9.1–10.2 years: Cavernous malformations represent 1.7–18% of all vascular malformations in children, and 25% of cavernous malformations are observed in children under 18 years of age, with a mean age of 9.1–10.2 years (34, 41).
Higher prevalence of familial cases in Hispanic-Americans: Cavernous malformations occur in two forms: sporadic and familial. The sporadic form occurs as isolated cases and most commonly with a single lesion. The familial form is characterized by multiple lesions and an autosomal dominant mode of inheritance. The proportion of familial cases has been estimated to be as high as 50% in Hispanic-American patients of Mexican descent, and close to 10–40% in other populations (14, 33, 52).
Prior radiation therapy: Lesions consistent with cavernous malformations of the brain are sometimes seen on MRI scans of patients who received radiation therapy for brain tumors as children. The lesions appear years later in brain tissue that was included in the radiation fields. They rarely require surgical excision and thus seldom have pathological confirmation. However, pathological analysis of three resected lesions showed typical characteristics of cavernous malformations (5). It is possible that cavernous malformations can occur after radiation therapy to the brain of children. These lesions are radiologically and pathologically similar to the idiopathic lesions.
Relationships to Other Disease States and Syndromes
Systemic cavernous malformations
Systemic cavernous malformations: Cavernous malformations as vascular malformations can occur both inside and outside the CNS, such as in the skin, mucosa, eye, liver, gastrointestinal tract, and spine. The incidence is rare, and the course is usually benign (47). The lesions can be sporadic or familial.
Blue rubber bleb nevus syndrome: This syndrome is characterized by multiple, distinctive angiomas of the skin, mucous membranes, and gastrointestinal tract. It is a variant form of systemic cavernous malformations.
Segmental cavernous malformations
Segmental cavernous malformations: Cavernous malformations are present in segmental vascular disease involving the spine in particular. The association of spinal cord vascular malformation, namely AVM, with a cutaneous angioma in the overlying dermatome is known as Cobb syndrome.