From the Departments of Anatomy University of Mississippi Medical Center, Mississippi, U.SA.
Abstract: (5403 Views)
Subarachnoid hemorrhage (SAH) resulting from a ruptured intracranial aneurysm
can induce cerebral vasospasm with subsequent reduction in cerebral blood flow
(CBF). The present study examines the pathological alterations in the wall of human
cerebral arteries at autopsy, especially with regard to intimal pathology, following
aneurysmal SAH. Arterial segments from the circle of Willis were fixed in 10%
formalin, embedded in paraffin, sectioned at 4µ and stained with hematoxylin-eosin
or toluidine blue. Similar numbers of sectioned vessels were also examined in control
material. The areas of intima, lumen and the length of internal elastic lamina were
compared witth those from control sections. Pathological changes such as myonecrosis
and fibrosis in muscular layers associated with a possible loss of compliance and
elasticity of the vessel wall were also noted. The average luminal area decreased to
56.8% ± 12.5% compared to comparable controls (p<0.005). The tunica intima was
the most abnormal component of the arterial wall with cellular proliferation which
was made up predominantly of collagen fibers and loose fibroblasts. These pathological
findings are mainly due to myonecrotic changes and intimal proliferation with the
resultant luminal constriction and CBF impairment which might explain the high
incidence of cerebral infarction in cases of SAH.