All of the neurocutaneous signs are seen in Neurofibromatosis Type 2, EXCEPT:
**Core Concept**
Neurofibromatosis Type 2 (NF2) is a rare genetic disorder characterized by the development of multiple noncancerous tumors in the nervous system, particularly in the brain and spinal cord. NF2 is distinct from Neurofibromatosis Type 1 (NF1) in terms of its clinical manifestations and genetic mutations.
**Why the Correct Answer is Right**
NF2 is primarily associated with the development of bilateral vestibular schwannomas, also known as acoustic neuromas, which are benign tumors that affect the balance and hearing nerves. The presence of these tumors is a hallmark of NF2 and is often used as a diagnostic criterion. In addition to vestibular schwannomas, NF2 can also involve other types of tumors, including meningiomas, ependymomas, and spinal cord tumors.
**Why Each Wrong Option is Incorrect**
**Option A:** Café-au-lait spots are a common feature of Neurofibromatosis Type 1 (NF1), not NF2. These are light brown or coffee-colored skin patches that can occur anywhere on the body.
**Option B:** Neurofibromas are also more characteristic of NF1, which is a distinct entity from NF2. Neurofibromas are benign nerve sheath tumors that can occur anywhere on the body.
**Option C:** Lisch nodules are small, pigmented lesions that occur on the iris and are a hallmark of NF1. They are not typically associated with NF2.
**Clinical Pearl / High-Yield Fact**
Neurofibromatosis Type 2 is often associated with a higher risk of developing meningiomas and other types of central nervous system tumors, particularly in individuals with a family history of the disorder.
**Correct Answer:** D.