Non-neoplastic, non-progressive congenital malformation in or around the hypothalamus.

It may be responsible for :

-        precocious puberty, as in Pallister-Hall syndrome (see this term)

-        epileptic seizures, usually pharmaco-resistant. Some of these seizures are pathognomonic, manifesting as paroxysmal laughter that is often bizarre and irrelevant. These are known as gelastic seizures (see gelastic epilepsy).

-        developmental, learning or neuropsychiatric disorders 

The type of symptomatology observed depends on the location and/or extension of the hamartoma (Delalande classification modified by Choi):

-        intrahypothalamic lesion (type I) connected to the posterior hypothalamus and IIIrd ventricle, near the mammillary bodies: epileptic seizures

-        parahypothalamic (type II) or pediculated lesion located near the anterior hypothalamus or the tuber cinereum or pituitary stalk, connected to the floor of the IIIrd ventricle: precocious puberty.

A combination of the 2 types of symptomatology is sometimes observed: type III or IV.

The histological appearance of the lesion is similar to gray matter, with mature ganglion cells, glial cells and myelinated and non-myelinated fibers. Macroscopically, they are spherical or ovoid lesions, varying in size from a few millimetres to several centimetres, attached to the tuber cinereum at the lower part of the hypothalamus, and sometimes including the mammillary tubercles.

Treatment: tumor removal by stereotactic thermo-coagulation (laser) or disconnection by intracranial video surgery.

Anesthetic implications: 

drug-resistant epilepsy; neurosurgery close to the third ventricle

References : 

-        Oehl B, Brandt A, Fauser S, Bast T, Trippel M, Schulze-Bonhage A.
Semiologic aspects of epileptic seizures in 31 patients with hypothalamic hamartoma.
Epilepsia 2010 ; 51:2116-23

-        Shim KW, Park EK, Kim JS, Kim DS. 
How would we deal with hypothalamic hamartomas? 
World J Surg Proced 2015; 5 : 65-74 [DOI: 10.5412/wjsp.v5.i1.65]

-        Wang S, Zhao M, Li T, et al.
Stereotactic radiofrequency thermocoagulation and resective surgery for patients with hypothalamic hamartoma.
J Neurosurg. 2020;1:1-8

-        Van Dong H,Van Dinh T, Dinh-Hoa N, Van Vu H5, Tuan Anh N et al.
Successful endoscopic disconnection for hypothalamic hamartomas in a child with gelastic seizures: an unusual case in a resource-scare setting.
International Medical Case Reports Journal 2020:13 425-9

Updated: January 2024