Box 1.

The gliosis and sclerosis group, comprising subforms described and named by Alzheimer (condensed excerpts).

Perivascular gliosis (perivasculäre Gliose). Characterized by severe arteriosclerosis of brain vessels and marked glial proliferation, with disseminated focal lesions in the cortex and white matter, restricted to one or more gyri, or single brain lobes, and expressed clinically as cortical focal disease (hemianopia, aphasia, cortical deafness, hemiplegia). Mild retraction or greater coarseness of a given gyral surface, on macroscopic neuropathology, and focal lesions with degeneration and loss of ganglion cells [neurons] and of myelinated fibers, on microscopy5,6,9.

Perivascular sclerosis (perivasculäre Sklerose). Previous description reiterated, with the assumption that it would be the cause of Perivascular sclerosis, due to stenosis of one larger arterial branch, with restriction of the necessary nutrition of the territory it supplied, and followed by the above-mentioned changes8.

Perivascular gliosis of the cerebral cortex(perivasculäre Gliose der Hirnrinde). Characterized by arteriosclerotic focal lesions and marked glia proliferation, unevenly distributed throughout the entire cerebral cortex. Small depressions on the cortical surface, with finely or coarsely granulated texture, on gross examination. Individual foci with wedge-shaped appearance, the broader side facing the surface, and the peak reaching the 4th or 5th cortical layer, on microscopy. Older foci evolving occasionally to small softenings, with a degenerated vessel in its central part, where the ganglion cells appeared destroyed, and the astrocytes replaced by coarse glia fibers7.

Perivascular sclerosis of the cerebral cortex (perivasculäre Sklerose der Hirnrinde). Seemingly a related condition to the previous subform which, depending on the affected site, can resemble clinically Senile dementia (e.g., Perivascular gliosis of the frontal lobe), or a slowly developing focal brain disease (cortical paralysis, aphasic symptoms, cortical deafness or blindness). Gross examination of the gyri proves unremarkable, where the severity of the cortical changes can be easily overlooked7.

Senile sclerosis of the cerebral cortex (senile Sklerose der Hirnrinde). The cerebral cortex exclusively affected due to arteriosclerotic degeneration of the small cortical vessels, in its pure form, along with sclerosis of small cortical areas with loss of the nervous elements and proliferation of sustaining tissue [glia]. Old foci often with wedgeshaped form, the wide base oriented toward the cortical surface8.

Senile cortical sclerosis [atrophy] (senile Rindeverödung). Due to disease of the short vessels from the pia mater entering the cerebral cortex, causing small wedge-shaped foci in the superficial cortex, with the base oriented toward the cortical surface, besides deeper cortical foci. Destroyed ganglion cells and myelinated fibers replaced by a dense glia felt [gliosis]. Foci often situated in clusters, in the supply territory of a larger artery, the more superficial related to punctate retractions on the cortical surface9.