HarP Protocol Confirms Link Between Hippocampus Volume, Alzheimer’s

4. Diagnostic Challenges
4. Diagnostic Challenges
Researchers set out to validate the new hippocampal measurement protocol against known markers for Alzheimer's.

After years of research, a team of researchers from the University of California Los Angeles have confirmed that the newly agreed-upon method for measuring hippocampal atrophy in structural MRI correlates with pathological changes known to be indicative of Alzheimer’s disease.

Following validation, the new Harmonized Protocol for Hippocampal Segmentation, or HarP protocol, which is meant to determine an accurate measurement of hippocampal volume in the brain, will likely be adopted by neurology researchers around the world. The protocol will also become an integral part in determining the efficacy of new therapies in clinical trials.

The European Alzheimer’s Disease Consortium–Alzheimer’s Disease Neuroimaging Initiative was partly established to address widespread inefficiencies in the measurement of the hippocampus; a key indicator of neurodegenerative disease but one that is very vulnerable to inconsistencies in measurement due to limits on the effectiveness of structural MRI and varied approaches used by researchers. In some cases, differences in imaging approach could result in differences of volume measurement as great as 2,000 cubic millimeters.

In order to validate the new approach to measuring hippocampal volume, the researchers utilized a 7 Tesla MRI scanner to conduct imaging of specimens from 16 postmortem brains, nine with confirmed Alzheimer’s and seven which were cognitively normal. The team was aiming to find a correlation between hippocampal volume and biomarkers of the disease, including a buildup of amyloid tau protein and neuron loss. The scans revealed that hippocampal volume strongly correlated with the state of amyloid tau buildup and neuron loss.

“As a result of the years of scientifically rigorous work of this consortium, hippocampal atrophy can finally be reliably and reproducibly established from structural MRI scans,” researcher Liana Apostolova, MD, MSCR said in a press release.

The researchers hope to further validate the HarP protocol for more automated techniques that can be used more widely in doctor’s offices and patient care settings to diagnose and monitor Alzheimer’s disease. 


  1. Apostolova LG et al. Alzheimers Dement. 2015; doi:10.1016/j.jalz.2015.01.001.