Hypothalamic hamartoma classification

Classification system proposed by Delalande and Fohlen in 2003. Type I: Hypothalamic hamartoma lesion in which the horizontal plane of attachment is completely below the floor of the third ventricle. Type II: Hypothalamic hamartoma lesion in which there is a vertical plane of attachment to the walls of the third ventricle, completely above the floor of the third ventricle. Type III: Hypothalamic hamartoma lesion in which the plane of attachment is both above and below the floor of the third ventricle, and thereby possessing a plane of attachment that is both vertical (in the third ventricle) and horizontal (attached to the inferior surface of the hypothalamus). Type IV: characterized as “giant” hypothalamic hamartoma lesions, without clear criteria for the boundary between Types III and IV. (Used with permission from Barrow Neurological Institute.)