Phakomatoses

The phakomatoses are a group of neurocutaneous disorders characterized by the involvement of structures that arise from the embryonic ectoderm (thus central nervous system, skin, and eyes). Other organs may also be involved.

Terminology

For practical purposes, the terms "phakomatoses" and "neurocutaneous disorders" can be considered synonymous.

Pathology

As a group, they are characterized by widespread abnormalities often with characteristic appearances. 

Most commonly seen:

• neurofibromatosis
  • neurofibromatosis type 1 (NF1) (von Recklinghausen disease)
  • neurofibromatosis type 2 (NF2) (mnemonic)
• tuberous sclerosis (Bourneville-Pringle disease)
  • tuberous sclerosis diagnostic criteria
• Sturge-Weber syndrome (encephalotrigeminal angiomatosis)
• von Hippel-Lindau disease (retinocerebellar angiomatosis | mnemonic)

Less common:

• ataxia telangiectasia
• incontinentia pigmenti (Bloch-Sulzberger syndrome)
• basal cell nevus syndrome (Gorlin-Goltz syndrome)
• Wyburn-Mason syndrome (Bonnet-Dechaume-Blanc syndrome)
• encephalocraniocutaneous lipomatosis 
• hypomelanosis of Ito
• Nijmegen breakage syndrome
• epidermal nevus syndrome
  • Schimmelpenning syndrome
  • phacomatosis pigmentokeratotica
  • nevus comedonicus syndrome
  • angora hair nevus syndrome
  • Becker nevus syndrome
  • Proteus syndrome
  • type 2 segmental Cowden disease
  • CHILD syndrome
  • FGFR3 epidermal nevus syndrome
• ​neurocutaneous melanosis 
• progressive facial hemiatrophy (Parry-Romberg syndrome)
• PHACE syndrome
• Cowden disease/COLD syndrome
• Gomez-Lopez-Hernandez syndrome