neuropil islands
Discrete areas of preserved neuropil surrounded by areas of tissue loss or gliosis. Characteristic finding in certain neurodegenerative conditions.
Full Definition
Neuropil islands are distinct regions of relatively preserved neural tissue that appear as discrete 'islands' surrounded by areas of significant tissue loss, gliosis, or other pathological changes. These structures represent areas where the normal complement of dendrites, axons, and synapses remains intact despite surrounding damage. Neuropil islands are characteristically observed in certain neurodegenerative diseases, particularly those involving selective vulnerability of specific neural populations. Their identification requires careful microscopic examination and can provide important insights into disease progression patterns and the relative resistance or susceptibility of different neural elements to pathological processes.
Usage
Usage note: Document size and distribution pattern for diagnostic significance.
In Context
- "Scattered neuropil islands were preserved within the otherwise gliotic white matter." — Progressive multifocal leukoencephalopathy case
- "The pattern of neuropil islands suggested selective vulnerability in this degenerative process." — Neurodegeneration study