phakomatoses


Also found in: Dictionary, Encyclopedia, Wikipedia.

phakomatoses

phakos, Greek, lens Neurocutaneous syndromes A group of inherited conditions–many are AD–that cause disordered growth of ectodermal tissues, with distinctive skin lesions and tumors and/or defects of the nervous system and/or retina
Phakomatoses
Ataxia-telangiectasia An AR disorder characterized by cerebellar ataxia, oculomotor apraxia, telangiectasias of bulbar conjunctiva, skin of ears, and skin folds–appearing by age 3–and sinopulmonary infections; telangiectasias later extend to the butterfly region of the face; most Pts die in adolescence
Basal cell nevus syndrome See there.
Nevus sebaceous of Jadassohn An occasionally AD clinical condition characterized by a congenital solitary lesion most often present in the scalp which, when large, may be associated with internal derangements eg intracranial masses, seizures, mental retardation, skeletal abnormalities, pigmentary changes, ocular lesions and renal hamartomas; 10% of the skin lesions develop into basal cell carcinoma
Sturge-Weber disease Encephalotrigeminal angiomatosis An occasionally AD condition characterized by congenital capillary hemangiomas of the head & neck, following normal developmental milestones, mental retardation may ensue, caused in part by the sluggish flow of blood through the pial vessels and venous hemangiomas in the leptomeninges and frontoparietal cortex with ipsilateral port-wine nevi, 'tram-track' radiopacities on the skull caused by calcification of the cerebral cortex
Tuberous sclerosis Bourneville-Pringle disease An AD disorder–50% arise de novo Clinical Convulsions, seizures, mental retardation, skin lesions–adenoma sebaceum, sebaceous gland atrophy, angiofibromas, dermal fibrosis with dilated capillaries, shagreen patches, cardiac rhabdomyomas, pulmonary fibrosis, bronchiolar hematomas, bilateral tubular adenomas of kidneys, pancreatic cysts, angiomyolipomas, myxedematous glossitis, spina bifida
von Hippel-Lindau disease An AD condition with retinal hemangioblastoma, ↓ erythropoietin production, cerebellar hemangioblastoma Clinical Ataxia, headache, papilledema, angiomas of the liver, kidney, renal adenomas, papillary cystadenomas of epididymis, pancreatic cysts, adrenal pheochromocytomas;14 develop renal cell cancer
von Recklinghausen disease A relatively common–1/3500 AD condition Clinical Neurofibromas, cafe-au-lait spots of skin, scoliosis, gliosis, glioblastoma multiforme, ependymoma, meningioma and schwannoma, 5-10% sarcomatous degeneration, spina bifida and glaucoma. See Neurofibromatosis.
Note: Neurofibromatosis, tuberous sclerosis, and von Hippel disease constitute the 'classic' phakomatoses

phakomatoses

A group of disorders that involve developmental abnormalities of tissue of ectodermal origin-tissue that gives rise to the skin and the nervous system. The three principal phakomatoses are TUBEROUS SCLEROSIS, VON HIPPEL-LINDAU DISEASE and the STURGE-WEBER SYNDROME.
References in periodicals archive ?
Patient age Chronicity Common causes MR imaging protocol Pediatric New Infection Basic MR brain Venous infarction imaging Metabolic abnormalities MRV/CTV Structural lesions Post contrast FLAIR (less common) Chronic Cortical dysplasias T2* Heterotopic grey matter GRE volumetric T1 Phakomatoses with multiplanar Cavernous malformations reconstructions Low-grade tumors MTS (after age 10) Adult New Infection T2* (younger patient) Post contrast FLAIR Prior trauma (younger patient) Remote infarct (older patient) Malignancy (older patient) Chronic MTS Cor T2* Cavernous malformations Cor T2 FLAIR Cortical dysplasia Cor GRE volumetric T1 Neoplasm Cor T2 with multiplanar reconstructions Prior trauma or infarction Table 3.
Neurofibromatosis type-1 (NF1) is the most common of all the phakomatoses, accounting for more than 90% of all cases, (1) and is the most frequently inherited single-gene disease in human beings.
The phakomatoses are a group of hereditary disorders that affect structures of ectodermal origin.