The phakomatoses (also known as neurocutaneous syndromes) are a heterogeneous group of disorders most characterized by the involvement of structures that arise from the embryonic ectoderm (thus central nervous system, skin, and eyes), although other systems may also be involved.
Pathology
As a group, they are characterized by widespread abnormalities often with characteristic appearances, and although generally due to failure of a tumor suppressor gene are not otherwise related.
Most commonly described:
von Hippel-Lindau disease (retinocerebellar angiomatosis)
Less common:
incontinentia pigmenti (Bloch-Sulzberger syndrome)
Wyburn-Mason syndrome (Bonnet-Dechaume-Blanc syndrome)
History and etymology
The concept of the phakomatoses was originated by Dutch ophthalmologist Jan van der Hoeve in 1921, who originally used the term 'phakoma' (from Greek 'lentil') to describe similar rentinal lesions seen in von Recklinghausen disease (then an umbrella term for both NF1 and NF2) and tuberous sclerosis, later expanding the grouping to include Sturge-Weber and Von Hippel-Lindau 3, 4.
Seperately, in 1931 the term 'neurocutaneous syndromes' was proposed by American neurologist Paul Yakovlev and psychiatrist Riley Guthrie, to describe the same conditions 5.