Certified Neuroscience Registered Nurse (CNRN) Practice Exam

What condition is most likely indicated by a patient's reported numb chin syndrome?

1. Intracranial hemorrhage

2. Metastatic cancer

3. Peripheral neuropathy

4. Trigeminal neuralgia

The correct answer is: Metastatic cancer

Numb chin syndrome is characterized by a loss of sensation in the chin and lower lip area, which can be a significant clinical indicator. This condition is particularly associated with metastatic cancer, especially when there is involvement of the mandible or surrounding structures, leading to involvement of the mental nerve, which provides sensation to the chin. In the context of metastatic cancer, the progression of the disease may cause pressure on or compromise nearby nerves, which can result in sensory changes such as numbness. This occurrence often raises a red flag for healthcare providers and may prompt further investigation for underlying malignancies, particularly in patients with a history of cancer or risk factors for it. While other options, such as intracranial hemorrhage, peripheral neuropathy, and trigeminal neuralgia, may involve sensory changes, they are not primarily associated with the isolated symptom of a numb chin as seen in numb chin syndrome. Intracranial hemorrhage often presents with more widespread neurological symptoms, peripheral neuropathy generally involves more diffuse symptoms, and trigeminal neuralgia mostly affects the facial sensations but does not specifically manifest as numbness of the chin alone. Thus, the association of numb chin syndrome with metastatic cancer makes it the most likely condition indicated in this scenario.