What is NF1?

It is more common that cystic fibrosis and hereditary muscular dystrophy combined.

NF1 has also been referred to as peripheral neurofibromatosis or von Recklinghausen disease. It differs clinically from another type of neurofibromatosis, called NF2. Individuals with NF1 will not develop NF2 and will not pass NF2 onto their children.


Cafe-au-lait Macules in NF1

Cafe-au-lait macules are flat, darkly pigmented spots or birthmarks on the skin, typically present at birth.

Cafe-au-lait macules in NF1
Cafe-au-lait macules in NF1

Skinfold Freckling in NF1

These freckles are commonly seen in patients with NF1 in areas of the body not exposed to the sun, like the armpits and groin. They also may be found under the neck or under the breasts in women.

Skinfold freckling in NF1
Skinfofld freckling in NF1

Lisch Nodules in NF1

These nodules are benign pigmented growths on the iris (the colored portion of the eye). They are usually found in both eyes but do not interfere with vision.

NF 1 Lisch Nodule


NF1 Neurofibromas

Neurofibromas are benign growths which typically develop on or just underneath the skin but may also occur within the body. These are seen in nearly all adults with NF1. These tumors are not contagious. This disease is progressive and the majority of people with NF will experience increases in tumor number and size. Regular evaluation in a coordinated care clinic specializing in NF1 is necessary to identify and address potential problems early. Read more about NF1 Neurofibromas.

NF1 Neurofibromas
NF1 neurofibromas

NF1 Plexiform Neurofibromas

In contrast, 25 to 30 percent of individuals with NF1 will develop a larger more diffuse type of neurofibroma, termed a plexiform neurofibroma, which can grow to large proportions and affect adjacent structures and organs. Rarely, these tumors can become malignant. Read more about NF1 Neurofibromas.


NF1 plexiform neurofibromas
NF1 plexiform neurofibromas
NF1 plexiform neurofibromas
NF1 plexiform neurofibromas
NF1 plexiform neurofibromas
NF1 plexiform neurofibromas

NF1 Optic Pathway Gliomas

Optic pathway gliomas are brain tumors that arise in the visual pathway and can lead to loss of vision or brain dysfunction. They typically are found in young children. Yearly eye exams by an experienced ophthalmologist are important to exclude visual abnormalities in preschool age children. Read more about NF1 Optic Nerve Glioma.

NF1 T2 Hyperintensities

NF1 T2 Hyperintensities


NF1 Bone Abnormalities

Children with NF1 are prone to the development of bone deformities involving the lower leg, forearm and eye socket. Deformities of the lower leg and forearms can cause a bowing of these bones and lead to repeated fractures. Those bone problems involving the eye socket can affect the way the eye sits in the socket. All of these bone deformities are typically noticed early in childhood and are treated promptly.

NF1 bone abnormalities
NF1 bone abnormalities

T2 Hyperintensities

Children with NF1 frequently will have T2 Hyperintensities on magnetic resonance imaging (MRI) of the brain. They are commonly located in the optic nerve pathway, basal ganglia, cerebellum, and brainstem. These bright spots are not tumors and will not develop into brain tumors. T2 Hyperintensities are most commonly seen in children and disappear in adulthood.


NF1 unidentified bright spots (UB0s)
NF1 unidentified bright spots (UB0s)

NF1 Learning Disabilities

Fifty to sixty percent of children with NF1 will have some form of learning disability. Learning disabilities frequently are seen in NF1 patients as specific problems with reading, writing and the use of numbers, in children with normal intelligence. However, children with NF1 rarely have mental retardation. Over 50% of children with NF1 also have issues with attention and executive function.  Many of these children are successfully treated with medication and behavioral therapy.   In addition, problems with fine and gross motor skills are frequently encountered in children with NF1. Affected individuals are often managed with physical and occupational therapy.

Inattentive girl in classroomLearning disabilities in the classroom