What is the classical triad of features of tuberous sclerosis? How often is the full hand present?
Seizures (absent in 1/4 of individuals), mental retardation (up to half of affected individuals have normal intelligence) and adenoma sebaceum (present in ~75% of patients). Overall only 30% of affected individuals demonstrate all three features.
What clue is visible supporting the history of long standing seizures?
The skull vault is thickened in keeping with long standing anti-epileptic medication (e.g. phenytoin).
What are subependymal giant cell astrocytomas?
Patients with TS are at increased risk of subependymal giant cell astrocytoma - a WHO grade 1 tumour. These cannot easily be distinguised from run-of-the-mill subependymal nodules on imaging, except they are usually larger, enhance vividly and most importantly demonstrate growth over time. Most of the time, they are located near or at the foramen of Monro.
True or false: Tuberous sclerosis changes are largely isolated to the brain and skin?
False. Very false. TS has a veritable Augean stable of systemic manifestations (see related articles).
Subcortical tubers (blue) and subependymal nodules (red) are easily discernible. Cortical tubers cannot be identified on non-contrast CT scans.