Internal Capsule Infarction Research Articles

Recurrent herpes zoster encephalitis: A case report

AbstractAn 89‐year‐old lady presented with severe right‐sided ophthalmic herpes zoster infection and secondary bacterial infection. Two weeks after admission she became very unwell with confusion and drowsiness and later developed bilateral upgoing plantar reflexes. An EEG was highly suggestive of herpes encephalitis and she made a good recovery with acyclovir. Neuropsychological tests showed pathological signs of impaired left temporal lobe function. After a further three weeks she again developed symptoms and signs of herpes zoster encephalitis and a repeat CT scan showed a right internal capsule infarct had developed. Encephalitis after herpes zoster infection is a rare complication but possibly underreported due to difficulties in diagnosis.

I-123 Hydroxyiodobenzyl Propanediamine (HIPDM) Cerebral Blood Flow Imaging Demonstrating Transtentorial Diaschisis

To assess the clinical significance of transtentorial diaschisis (TTD) as demonstrated by I-123 HIPDM brain imaging, SPECT and/or planar images of 35 patients with stroke, 26 patients with Alzheimer's disease (AD), 2 patients with Creutzfeldt-Jakob disease (CJD), and 1 patient with a schizoaffective disorder were analyzed. TTD was observed in 21 of the 35 patients with strokes. In 13 stroke patients, TTD was associated with large infarcts in the middle cerebral artery (MCA) territory; in the remaining 8 stroke patients, TTD was associated with internal capsule and/or basal ganglia infarcts. TTD was not associated with small occipital or parietal infarcts. Despite cortical perfusion decrements, TTD was not seen in the AD patients, the CJD patients, or the patient with schizoaffective disorder. It is concluded that 1) TTD frequently occurs following cerebral infarct of the MCA territory (60% of the patients in this sample); 2) absence of TTD in the presence of a large cerebral perfusion abnormality may represent neuronal dysfunction of the cerebral cortex; and 3) the presence of TTD without a significant cortical perfusion abnormality may indicate basal ganglia and/or internal capsule infarct.

Effects of capsular or thalamic stroke on metabolism in the cortex and cerebellum: a positron tomography study.

We used positron emission tomography to study the cortical and cerebellar metabolic rates in 21 strictly selected patients with pure internal capsular infarct (n = 8), thalamocapsular hemorrhage (n = 6), or pure thalamic stroke (n = 7). Significant diffuse ipsilateral cortical hypometabolism relative to 62 controls free of cerebrovascular risk factors was frequently, although not consistently, found in the 13 patients with thalamocapsular or thalamic lesions and neuropsychological impairment but was absent from the eight patients with pure internal capsule infarct and free of neuropsychological deficit. These data suggest that damage to the thalamus or the thalamocortical projections is important in the development of ipsilateral cortical hypometabolism and that the latter may underlie the associated neuropsychological impairment. Significant contralateral cerebellar hypometabolism relative to 49 controls was found in three of six patients with pure internal capsule infarct, suggesting a pathogenetic role for the corticopontocerebellar system. However, the occurrence of hypometabolism in two of six patients with thalamic lesions indicates that this phenomenon may also result either from damage to the ascending cerebellothalamocortical system or indirectly from hypofunction of the cerebral cortex. No systematic association was observed between crossed cerebellar hypometabolism and ipsilateral ataxia.

Pure dysarthria due to anterior internal capsule and/or corona radiata infarction: a report of five cases.

Five cases with a sudden onset of dysarthria in the setting of hypertension are presented. No case had limb weakness or other neurological deficits. Computed tomographic scan demonstrated a small low density lesion in the anterior part of the internal capsule or the adjacent corona radiata. All cases showed a good recovery from dysarthria within two to four weeks.