Disproportionately enlarged subarachnoid-space hydrocephalus (DESH) in normal pressure hydrocephalus misinterpreted as atrophy: autopsy and radiological evidence

ABSTRACT

Disproportionately enlarged subarachnoid-space hydrocephalus (DESH), a feature of normal pressure hydrocephalus (NPH), is often misinterpreted as cortical atrophy. We report a 67-year-old man with features of NPH but not diagnosed because radiographic findings were interpreted as cortical atrophy. Autopsy showed findings consistent with NPH and no neurodegenerative disease. The second patient with DESH underwent shunt surgery. Entrapped fluid diminished after the surgery, confirming this is not atrophy, but due to a CSF dynamic process. Patients with DESH have tight sulci adjacent to the entrapped fluid pockets, distinguishing it from cortical atrophy. 18F-Fluorodeoxyglucose PET can help differentiate DESH from cortical atrophy.

KEYWORDS:

• Hydrocephalus
• DESH
• atrophy
• MRI
• FDG PET
• ventriculoperitoneal shunting

Acknowledgments

The authors acknowledge support from the brain bank for neurodegenerative disorders at Mayo Clinic, including Rachel LaPaille-Harwood, Virginia Phillips, Michael DeTure, and Monica Castendes-Casey.

Availability of data and materials

Individual de-identified participant data will be shared, including neuroradiologic images, gross and microscopic neuropathology images, and redacted medical summaries. The study did not involve a research study protocol or statistical analysis. Data will be made available for a period of not more than 5 years after publication. All reasonable requests for data will be provided upon written request to either Dr. Graff-Radford or Dr. Dickson.

Author contributions

Arthur M. McCarty: drafting of manuscript, acquisition of data

David T. Jones: drafting of manuscript, acquisition of data, analysis and interpretation of data, critical revisions

Dennis W. Dickson: study concept and design, acquisition of data, interpretation of data, critical revisions

Neill R. Graff-Radford: study concept and design, critical revisions, interpretation of data, acquisition of data

Disclosure statement

Arthur M. McCarty and David T. Jones declare no competing interests.

Dennis W. Dickson receives research support from the NIH (P50 AG016574; P50-NS072187; P01-AG003949) from the Rainwater Foundation, the Mangurian Foundation Lewy Body Dementia Program at Mayo Clinic and the Robert E. Jacoby Professorship. Dr. Dickson is an editorial board member of Acta Neuropathologica, Annals of Neurology, Brain, Brain Pathology, and Neuropathology, and he is editor-in-chief of American Journal of Neurodegenerative Disease.

Neill R. Graff-Radford serves on the editorial boards of The Neurologist and Alzheimer Disease and Therapy; has received publishing royalties from UpToDate, Inc.; and receives research support from Biogen, Lilly and Axovant. He has consulted for Cytox.

Additional information

Funding

This work was supported by the NIH under grants [P50-AG016574, P50-NS072187, and P01-AG003949]; the Rainwater Foundation; the Mangurian Foundation Lewy Body Dementia Program at Mayo Clinic; and the Robert E. Jacoby Professorship.