Hyperspectral Retinal Observations for the Cross-sectional Detection of Alzheimer's Disease

Two devices will be tested in this research:

1. Mantis Photonics' hyperspectral camera for non-invasive retinal examination (i.e., a hardware medical device under investigation).
2. Blekinge CoGNIT cognitive ability test (i.e., an assessment).

Worldwide, millions of people are affected by neurodegenerative diseases (e.g., Alzheimer's disease, dementia). Those diseases are having a tremendous socio-economic impact on our society. The cost associated with treating and caring for those diseases is enormous. Overwhelming evidence indicates how selective lifestyle changes (e.g., reducing exposure to known risk factors) can sometimes significantly decrease the probability of developing the disease or delay its onset. However, the diseases must be diagnosed early for them to be effective. There is a lack of accessible, inexpensive, and non-invasive practices that would allow for an early diagnosis of different diseases, even at the primary physician's office. Mantis Photonics and Blekinge Tekniska Högskola (Institustionen för Hälsa) aim to fill this urgent unmet medical need.

Strong indications of the possibility of classifying Alzheimer's status based on hyperspectral scans of the retina have been published by different researchers. These results were obtained based on images taken with hyperspectral cameras with a different working principle than the Mantis Photonics camera. The working principle of the Mantis Photonics camera allows making a hyperspectral retinoscopy with the same spectral range and comparable or better spectral resolution with a machine that is more modular and lower in cost. There is thus reason to hypothesize retinal scans taken with the Mantis Photonics camera can be used for the same classification task.

Previous studies on the automated tablet computer cognitive test CoGNIT have established validity, reliability and sensitivity for testing patients with Normal Pressure Hydrocephalus (NPH) . Recently feasibility of testing in Mild Cognitive Impairment (MCI) was affirmed (Behrens, Berglund, \& Anderberg, CoGNIT Automated Tablet Computer Cognitive Testing in Patients With Mild Cognitive Impairment: Feasibility Study, 2022). In NPH patients, CoGNIT was more sensitive to cognitive impairment at baseline and cognitive improvement after shunt surgery than the Mini-Mental State Examination (MMSE).

Blood tests for amyloid-β and other biomarkers related to Alzheimer's disease are being investigated for clinical practice, but the technique is not accepted as a standard test. Research has shown that renal function influences amyloid-β clearance from the body. Also, analytical errors influence test results. Therefore, one can question the influence of normal repeatability of the blood test result.

The aim of this investigation is the evaluation, (further) development and comparison of non-invasive techniques for the evaluation of patients suffering mild cognitive impairment, in particular, the Mantis Photonics hyperspectral camera with classification machine learning model in combination with the CoGNIT test of Dr Behrens (Blekinge Tekniska Högskola). These techniques will be compared to the result of cerebrospinal fluid analysis (CSF), the reference biological diagnostic technique for Alzheimer's disease.

Eligibility Criteria:
Inclusion Criteria:

* subject age over 18 years old
* The subject has undergone a lumbar puncture an cerebrospinal fluid analysis as part of the standard care.
* The subject has at least one healthy eye.
* The subject is applicable for taking a blood sample for the blood analysis test.
* The informed consent is provided, explained and understood by the person. The person has consented to the informed consent.

Exclusion Criteria:

* There are contra-indications for lumbar puncture (eg: brain tumor with suspicion of raised intracranial pressure, coagulopathies or ongoing anticoagulant medications) will be excluded from the study.
* When the subject suffers from excessive visual or auditive impairment, the he/she will be excluded from the CoGNIT track.