MR differential diagnosis of normal-pressure hydrocephalus and Alzheimer disease: significance of perihippocampal fissures.

Publication Type	Academic Article
Authors	Holodny A, Waxman R, George A, Rusinek H, Kalnin A, de Leon M
Journal	AJNR Am J Neuroradiol
Volume	19
Issue	5
Pagination	813-9
Date Published	05/01/1998
ISSN	0195-6108
Keywords	Alzheimer Disease, Hippocampus, Hydrocephalus, Normal Pressure, Magnetic Resonance Imaging
Abstract	PURPOSE: In the older patient with dilated ventricles, it is often difficult to differentiate normal pressure hydrocephalus (NPH) from cerebral atrophy caused by Alzheimer disease (AD). This study was undertaken to see if dilatation of the perihippocampal fissures (PHFs) could be used as a distinguishing characteristic of these two disorders. METHODS: MR images of 17 patients with AD were compared with those from an equal number of patients with NPH who improved after ventriculoperitoneal shunting. The PHFs, lateral ventricles, third ventricle, and temporal horns were graded subjectively. Objective, computer-aided volumetric measurements of the PHFs and lateral ventricles were obtained. The preshunt images of the NPH patients were evaluated. RESULTS: Significant differences between the two groups were found for the PHFs and lateral ventricles by both the subjective and objective methods, with a high degree of correlation between the two methods. CONCLUSION: The degree of dilatation of PHFs appears to be a sensitive and specific marker for differentiating AD from NPH by both subjective and objective means, with a very small overlap between the two groups. This observation may have relevance in day-to-day practice.
PubMed ID	9613493
PubMed Central ID	PMC8337558