Hemosiderin is a form of iron .. deposit ..
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perivascular hemosiderin deposition
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Epilepsia. 2005 Sep;46(9):1495-501. Related Articles, Links
Unusual findings in brain biopsies of two patients with acute magnetic
resonance imaging lesions associated with focal seizures.
McClelland S 3rd, Libien JM, Chin SS, Adams DJ, Resor SR Jr, Chan S,
Goodman RR.
Department of Neurological Surgery, ColumbiaCollege of Physicians and
Surgeons, New York, New York 10032, USA.
PURPOSE: Patients with focal seizures often have magnetic resonance
imaging (MRI) abnormalities in the brain region of their presumed
seizure focus. Neoplasms, ischemic infarctions, inflammatory processes,
and other specific pathologic entities have been diagnosed by biopsies
of such MRI abnormalities. Two patients with this presentation had
brain lesion biopsies with a leading presumptive diagnosis of glial
neoplasm but were found to have indistinct histopathology. METHODS:
Each patient was initially seen with focal seizures (right parietal
region, right hippocampus) corresponding with focally increased T2
signal on MRI. In both patients, the preoperative clinical suspicion
was for neoplastic or inflammatory processes. RESULTS: Several weeks
after seizure onset, craniotomy in patient 1 and stereotactic needle
biopsy in patient 2 revealed mild gliosis with reactive vascular
changes and perivascular hemosiderin deposition, not diagnostic of but
compatible with venous congestion (or possibly venous thrombosis).
Postoperatively, patient 1 had brief sensory seizures that stopped 5
months after surgery, whereas subsequent seizures did not develop in
patient 2. Both patients had normalization of their MRI (except for
postoperative changes) and have remained seizure free. CONCLUSIONS: We
describe two patients who had brain biopsies of striking focal
increased T2 signal MRI abnormalities associated with seizures.
Pathologic findings contradicted our preoperative suspicions (neoplasm
or inflammatory process), compatible with (but not conclusive for)
subacute venous congestion/thrombosis. These findings indicate that
patients with seizures may have an associated discrete intraaxial MRI
lesion that is not neoplastic. To our knowledge, this is the first
report of focal seizure-associated MRI lesions with biopsy findings
compatible with venous congestion/thrombosis.
PMID: 16146445 [PubMed - in process]
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