**7. Raman spectroscopy for the diagnosis of dementia**

Alzheimer's disease is the most prevalent type of neurodegenerative dementia in the elderly population worldwide. The key for efficiently and accurately diagnosing dementia occurs during the early stages. Scientists struggle to find a blood-based method to perform an accurate diagnosis of this type of dementia, which affects 35.6 million people worldwide [58].

In this context, Raman microspectroscopy was already used to analyze serum of Alzheimer's disease patients, patients with other dementias and healthy controls. Data were analyzed with multivariate statistics for the differential identification of Alzheimer's disease patients. The study was a proof of concept; however, it proves that Raman microspectroscopy and artificial neural network classification were able to differentiate patients with more than 95% sensitivity and specificity, demonstrating that Raman has potential to become a blood-based tests that may help clinical assessments for effective and accurate differential diagnosis of Alzheimer's disease [59].
