[Pathomorphology and pathogenesis of leptomeningeal hemorrhages in fetuses and newborn infants].

Leptomeningeal hemorrhages (LMH) were studied neurohistologically and electron-microscopically on 54 stillborn and liveborn infants. Five main types of LMH were revealed: diapedesal in the grooves; punctate; macular; large focal, and hematomas. In 33.3% of cases there was a combination of different LMH types. Their morphological and pathogenetic features are described. LMH are further subdivided according to the number of foci as single and multiple, according to their extension as generalized and localized, according to their localization as unilateral or bilateral (symmetric and asymmetric) and according to the localization of extravasation as subarachnoid, subpial and mixed. The most significant lesions of the underlying dura matter are observed in cases of large focal LMH and hematomas.