Abstract

Background: An Evans’ index (EI) greater than 0.3 has been associated with a diagnosis of idiopathic normal pressure hydrocephalus (iNPH). However, ventricular enlargement is also present in Alzheimer's disease (AD) in the elderly. To assess the differences between ventricular enlargement in AD and iNPH, we developed a geometric model that incorporated different linear brain measurements and compared it with EI.

Materials and Methods: Different ventricular linear measurements were obtained from 124 brain CT scans of normal participants, AD and iNPH patients. We developed a geometric model that yielded a linear measurement proportional to the skull shape.

The maximum frontal horn distance was divided by this new tool and compared with EI to identify a cutoff point that can allow radiological differentiation between AD and iNPH.

Results: The area under the receiver operating characteristic curve (ROC) when EI was used was 0.803, and the corresponding value with the geometric model (VW_N) was 0.802, i.e. almost identical. The cutoff EI to differentiate between AD and iNPH was 0.36, and the cutoff VW_N to distinguish between AD and iNPH was 1.6.

Conclusion: We show that our novel geometrical method is similar to EI for identifying AD and iNPH. Further research and validation of other ventriculomegaly pathologies are required to increase the usage of the geometrical method. Different patterns of ventricular dilatation with size differences in the dilated frontal ventricular horn are observed in AD and iNPH; linear brain measurements can characterize these differences.

Keywords: Normal Pressure Hydrocephalus; MRI; Dementia; Alzheimer Disease

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Citation

Citation: Marcos Escosa Bage., et al. “Novel Brain Linear Measurements to Differentiate between Alzheimer Disease and Normal Pressure Hydrocephalus". Acta Scientific Neurology 3.12 (2020): 32-38.

Copyright

Copyright: © 2020 Marcos Escosa Bage., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.