Absence seizures
Frequent, brief events (lasting 5-30 seconds). Someone experiencing an absence seizure may briefly loose awareness, stop talking or stare.

Atonic seizures
Seizures that involve a loss of tone in the head, upper torso or whole body.

Attention-deficit/hyperactivity disorder (ADHD)
ADHD can difficulties with staying focused and may also cause behavioural problems, and hyperactivity.

Angiomyolipomas (AMLs)
Growths composed of blood vessels, smooth muscle, and fat tissue.
Autism / Autistic Spectrum Disorder
A disorder of neural (brain) development. People affected by autism may have difficulties with social interaction and communication and may also have repetitive behaviours.

Cardiac rhabdomyomas
Growths in the heart that are present at birth, which get smaller with age and disappear in adult life.

Computed tomography (CT)
A type of imaging that uses x-rays to create a computer-generated, 3D image of a body structure.

‘Confetti’ skin lesions
Light patches of skin measuring 1 to 3 mm that are scattered on the arms and legs.

Cortical tubers
Small areas in the cortex (the outer layer of the brain) which do not develop normally. It is thought that cortical tubers disrupt the normal ‘wiring’ of the brain and cause seizures.

Echocardiography (ECG)
Ultrasound used to examine the structures of the heart.

Electroencephalogram (EEG)
A recording of the electrical activity of the brain.

Epileptic seizure
An abnormal, excessive, sudden discharge of electrical impulses by the neurons in the brain.

Facial angiofibromas
Flesh-coloured or red growths, typically occurring over the nose, cheeks and chin.

A condition that occurs in more family members than would be expected by chance.

A growth that is composed primarily of fibrous tissue.
Forehead plaque
Raised, discoloured areas on the forehead.

Gingival fibromas
Growths consisting mainly of fibrous tissue that are found in the gums.
These growths are made up of abnormally developed tissue that is natural to a part or organ.

High-resolution chest computed tomography (HRCT)
A scan that takes x-rays of the chest at slightly different angles. A computer produces a detailed picture of the inside of your body and the airways inside your lungs (the bronchi) should show up clearly.

An increase in the amount of (cerebrospinal) fluid in the brain.

Hypomelanotic macule
A patch of skin that is lighter than the surrounding skin.
Lymphangioleiomyomatosis (LAM)
A build up of smooth muscle cells in the airways of the lungs. LAM may lead to the growth of cysts in the lungs.
Magnetic resonance imaging (MRI)
MRI uses a powerful magnet, radio waves and a computer to produce images of the inside the body.

When a person possesses cells of two or more different genetic compositions.
Relating to the ability to think and reason and involving the central nervous system.

Periungual fibroma
A growth found on a fingernail or toenail that is made up mostly of fibrous tissue.

Polycystic kidney disease
A hereditary condition that causes cysts to form on both kidneys.

Shagreen patch
An area of thick, leathery skin usually found on the lower back or nape of the neck.

Skin tags
Harmless skin growths that resemble a small piece of soft, hanging skin.

Somatic mosaicism
The presence of two or more populations of cells with different genotypes (genetic makeup) in a single person.

Subependymal giant cell astrocytomas (SEGAs)
Also know as SGCT, a growth that is usually found in the ventricles of the brain. Ventricles are natural spaces inside the brain that are filled with fluid.
Subependymal nodules (SENs)
A type of growth that develops near the walls of the ventricles of the brain. Ventricles are natural spaces inside the brain that are filled with fluid.

TSC Associated Neuropsychiatric Disorders.
Tonic-clonic seizures
These used to be called ‘grand mal’ seizures. This type of seizure begins with stiffening of the extremities followed by jerking of all extremities. Most tonic-colonic seizures last less than three minutes.

The tuberous sclerosis 1 gene that produces a protein called ‘hamartin’. Together hamartin and tuberin (the product of the TSC2 gene) play a role in cell growth and division.

The tuberous sclerosis 2 gene that produces a protein called ‘tuberin’. Together tuberin and hamartin (the product of the TSC1 gene) play a role in cell growth and division.

An abnormal mass of tissue in the body. In TSC, tumours are benign (non-cancerous).

Part of a system of communicating cavities in the brain or heart. In the brain, ventricles are natural spaces that are filled with fluid.

Wood's lamp
A lamp that gives out ultraviolet (UV) light. This type of lamp makes it easier to see areas of skin that have less pigment than surrounding skin.

If you there is a term you would like us to add, please email sophie.jenkin@tuberous-sclerosis.org