Subependymal giant cell astrocytoma is blocking the foramen of Monro, causing massive hyrdocephalus. Cyst of the frontal horn of the lateral ventricle has caused subfalcine hernation. Both of these findings are typical for tuberous sclerosis. The pathologic hydrocephalus is particularly worrisome and must be treated emergently.
Neurocutaneous syndrome with autosomal dominant inheritance pattern with the development of hamartomas and benign neoplasms.
Genetics
Autosomal dominant inheritance pattern
TSC1 mutation on chromosome 9
TSC1 encodes for hamartin.
TSC2 mutation on chromosome 16
TSC2 encodes for tuberin.
Both hamartin and tuberin are involved in inhibition of the mechanistic Target of Rapamycin (mTOR) pathway (mTOR is also an important factor in the development of gliomas in Neurofibromatosis, Type 1).
Clinical Manifestations:
Hamartomas (firm, like "potatoes") of the CNS (cortex) and skin.
Note that Everolimus is an mTOR inhibitor and is used in the treatment of enlarging SEGAs.
Cysts
Candle Guttering Sign
Note that the "candle gutterings" are sub-ependymal nodules found in tuberous sclerosis: they are smooth, round projections into the ventricles that look like drippings of wax along a candle.
References
“December 27, 2010 e-Pearl of the Week: ‘Candle Guttering’ Sign in Tuberous Sclerosis | Neurology.” Accessed August 6, 2018. http://n.neurology.org/epearls/20101227.