Types of NF
Of the two types of neurofibromatosis — NF1 and NF2 — NF1 is more common, occurring in 1 of every 2,500-3,000 births and affecting an estimated 100,000 Americans. It is also known as von Recklinghausen disease.
NF2 is characterized by the presence of bilateral acoustic neurofibroma-like tumors and is rarer, seen in 1 in 25,000 births. People with NF2 usually develop benign tumors on the nerves in their ears, causing hearing loss, eventual deafness, and problems with balance.
The severity of both types of neurofibromatosis varies greatly. In families where more than one person has NF, it can present with different physical signs and complications for each person. At diagnosis, it isn't possible to know right away whether a case will be mild or lead to severe complications.