Alzheimer's disease is a condition that affects the brain and is associated with the build-up of waste substances that can damage brain cells. Scientists have recently discovered a natural drainage and cleaning system around the brain, called the meningeal lymphatic system, which may help remove these waste products.

Researchers believe that this brain drainage system is connected to lymph nodes located in the neck. However, this connection has not yet been clearly demonstrated in humans because it is difficult to study.

The purpose of this study is to investigate how fluid drains from the brain to the lymph nodes in the neck. To do this, researchers will use a fluorescent dye called indocyanine green, which can be seen with a special camera. The study will be carried out in potential organ donors who have been authorized for organ donation.

The researchers will record images and videos to observe how the dye moves, how long it takes to reach the lymph nodes, whether the drainage is similar on both sides of the body, and which lymph nodes are involved.

A better understanding of these drainage pathways may help researchers develop and improve future treatments for Alzheimer's disease and other neurological disorders.

Design Prospective interventionist study: in which the flow of lymph fluid from the intracranial region to the deep cervical ganglia will be studied in the potential organ donor (PDO).

Study population Potential organ donor patients (PDO), both donors in Brain Death and Donors in Controlled Asystole, candidates to perform extraction thereof and authorized by the Transplant Coordination of the University Germans Trias i Pujol Hospital.

total number of subjects There will be 20 flow measurements, so if it is bilateral, there would be 10 potential donors.

Variables Images and videos will be obtained using the fluorescence camera. To be evaluated: time, direction, ganglion levels, symmetry. Data source Memory storage of the PDE (Hamamatsu, Photonics) fluorescence device. They will be collected in a database.

Medical history of the donor. Medicinal product or medical device under evaluation (where applicable) Not applicable Data analysis The images and videos collected will be evaluated, analyzing the variables in the different corpses.

Inclusion Criteria:

• Potential organ donor patients, both in Brain Death and in Controlled Asystole, candidates to perform organ harvesting authorized by the Transplant and Tissue Coordination of the Universitary Germans Trias i Pujols Hospital, according to the usual channels and whose family members have previously signed the authorization of the donation and the specific informed consent of the study. Will be included in the study always after death is certified by neurological or cardiocirculatory criteria

Exclusion Criteria:

• Absence of informed consent signed by family members.
• Individuals with a history of having intracranial lymphatic drainage affected.

The porpouse of this clinical study is to know the existence of a migration flow from the meningeal lymphatic system and cervical lymph nodes. It doesn't describe the population or subjects