Operationalizing protocol differences for EADC-ADNI manual hippocampal segmentation

Alzheimers Dement. 2015 Feb;11(2):184-94. doi: 10.1016/j.jalz.2013.03.001. Epub 2013 May 21.


Background: Hippocampal volumetry on magnetic resonance imaging is recognized as an Alzheimer's disease (AD) biomarker, and manual segmentation is the gold standard for measurement. However, a standard procedure is lacking. We operationalize and quantitate landmark differences to help a Delphi panel converge on a set of landmarks.

Methods: One hundred percent of anatomic landmark variability across 12 different protocols for manual segmentation was reduced into four segmentation units (the minimum hippocampus, the alveus/fimbria, the tail, and the subiculum), which were segmented on magnetic resonance images by expert raters to estimate reliability and AD-related atrophy.

Results: Intra- and interrater reliability were more than 0.96 and 0.92, respectively, except for the alveus/fimbria, which were 0.86 and 0.77, respectively. Of all AD-related atrophy, the minimum hippocampus contributed to 67%; tail, 24%; alveus/fimbria, 4%; and the subiculum, 5%.

Conclusions: Anatomic landmark variability in available protocols can be reduced to four discrete and measurable segmentation units. Their quantitative assessment will help a Delphi panel to define a set of landmarks for a harmonized protocol.

Keywords: Alzheimer's Disease Neuroimaging Initiative; Alzheimer's disease; Anatomic landmark; Atrophy; Degeneration; Harmonization; Hippocampal atrophy; Hippocampal volumetry; Hippocampus; Magnetic resonance; Manual segmentation protocol; Manual tracing; Medial temporal lobes; Neuroimaging; Standard operating procedures.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Alzheimer Disease / pathology
  • Atrophy
  • Cognitive Dysfunction / pathology
  • Delphi Technique
  • Female
  • Hippocampus / anatomy & histology
  • Hippocampus / pathology*
  • Humans
  • Image Processing, Computer-Assisted / methods*
  • Imaging, Three-Dimensional / methods
  • Magnetic Resonance Imaging / instrumentation
  • Magnetic Resonance Imaging / methods*
  • Male
  • Neuroimaging / methods*
  • Organ Size
  • Reproducibility of Results