A Case of Unilateral Hippocampal Infarction with Acute Memory Loss

BACKGROUND: Memory impairment results from various neurologic disorders. Among them, the memory loss associated with stroke is called amnesic stroke. Involved regions in the amnesic stroke are medial temporal lobe, thalamus, basal forebrain, retrosplenial region, and subcortical regions. Unilateral amnesic stroke is posterior cerebral artery territory including thalamus. Isolated infarction of hippocampal region has been rarely reported because hippocampus has dual blood supply from anterior choroidal cerebral artery and posterior cerebral artery. CASE REPORT: A 61-year old male with a history of diabetes for 6 years and hypertension for 13 years, was admitted with acute memory loss occurring 6 days before admission. He could not remember the exact date, place and recent events but could remember remote events about his personal and familial affairs. Brain MRI revealed an infarction in left hippocampal region and cerebral angiography showed multiple focal stenosis and luminal irregularity on left anterior choroidal, middle cerebral, basilar and both posterior cerebral arteries. COMMENTS: We report unilateral amnesic stroke only confined to left hippocampal region with literature review.

2 cases of plasma cell granulomas involving intracranium

Plasma cell Granuloma (PCG) is a form of idiopathic inflammatory pseudotumor (IPT). It is a rare entity character-ized by a nonneoplastic proliferation of inflammatory cells dominated by a polyclonal expansion of the plasma cells. This lesion has been discovered in many parts of the body including the central nervous system. We now report two cases of plasma cell granuloma involving the brain. The first case was a 42-year-old man who presented a right hemi-paresis. He had a lesion in the convexity of the left parietal region. The second case was a 58-year-old woman who was expressed confusion and a frontal-temporal headache. She had a lesion in the convexity of the left temporal region and mastoid bone. The diagnosis of PCG was confirmed by pathological and immunohistochemical studies revealing pre-dominant plasma cells in the affected tissues.

Multifocal ischemic lesions and focal hematoma formation in a meningitis

Cerebrovascular complications are of the most frequent intracranial complications of bacterial meningitis. Most of the previous reports suggest that the prognosis for the pafients with cerebrovascular complications was unfavorable. We recently experienced a case of meningococcal meningitis with fulminant meningococcemia associated with multifocal non-enhancing lesions on, initial brain MRI. These lesions were hyperintense on T2weighted image and were located in left basal ganglia, both medial thalami, periventricular white matter, left cerebellar hemisphere, and right midbrain and were considered to be resulted from small vessel involvement. Gram negative diplococci were detected by Gram staining of specimens from skin lesion. After antimicrobial therapy and glucocorticoid replacement the patient was recovered without any neurologic sequelae. After one month, follow-up MRI showed resolution of all the ischemic lesions except in midbrain. Additionally there was a small focal hemtoma formation in left basal ganglia. The small hematoma was considered to be resulted from rupture of microaneurysm and disappeared on follow up MRI performed after 3 months. This case suggests that the cerebrovascular complications in meningococcal mningitis might be treated successfully.