1/6. Cerebellar dysfunction in chronic toluene abuse: beneficial response to amantadine hydrochloride.CASE REPORT: A 21-year-old man who had sniffed toluene since the age of 13 presented with a 4-year history of progressive cerebellar dysfunction and visual deterioration. The patient's condition did not improve despite 5 months of abstinence. magnetic resonance imaging revealed cerebral atrophy and hypointensity signals in the white matter and bilaterally in the globus pallidus, thalamus, red nucleus, and substantia nigra. amantadine hydrochloride therapy (100 mg/d, then 200 mg/d) resulted in dramatic improvement of his cerebellar and visual symptoms.- - - - - - - - - - ranking = 1keywords = nucleus (Clic here for more details about this article) |
2/6. Complex visual hallucinations (Charles Bonnet syndrome) in visual field defects following cerebral surgery. Report of four cases.The development of visual hallucinations after loss of vision is known as the Charles Bonnet syndrome. This phenomenon was first described in 1760 by Charles Bonnet and others during their observations of elderly patients with degeneration of the retina or cornea. To date a clear association between visual hallucinations and neurosurgical procedures has not been reported. Because of their clear demarcation, however, surgical lesions in the cerebrum offer a unique opportunity to determine the pathoanatomical aspects of visual hallucinations. During a 3-year period, 41 consecutive patients who acquired visual field defects after neurosurgery were examined for the occurrence of visual hallucination. Postoperatively, four of these patients experienced visual hallucinations. In two of them an upper quadrantanopia developed after the patients had undergone selective amygdalohippocampectomy. In the other two patients a complete hemianopia developed, in one case after resection of a parietal astrocytoma and in the other after resection of an occipital glioblastoma multiforme. The visual hallucinations were transient and gradually disappeared between 4 days and 6 months postoperatively. The patients were aware of the fact that their hallucinations were fictitious and displayed no psychosis. Electroencephalographic recordings were obtained in only two patients and epileptic discharges were found. Deafferentiation of cortical association areas may lead to the spontaneous generation of complex visual phenomena. In the present series this phenomenon occurred in approximately 10% of patients with postoperative visual field defects. In all four cases the central optic radiation was damaged between the lateral geniculate nucleus and the primary visual cortex. The complex nature of the visual hallucination indicates that they were generated in visual association areas.- - - - - - - - - - ranking = 1keywords = nucleus (Clic here for more details about this article) |
3/6. Severe delirium due to basal forebrain vascular lesion and efficacy of donepezil.A severe intractable delirium caused by the basal forebrain vascular lesion and its dramatic recovery after donepezil administration were reported. A 68-year-old man had suffered for a month from delirium of mixed type caused by the right basal forebrain vascular lesion after surgery for craniopharyngioma. magnetic resonance imaging (MRI) showed hemorrhagic infarcts in the head of the right caudate nucleus and the right basal forebrain of the medial septal nucleus, diagonal band of broca and nucleus basalis of Meynert. He had been treated with anti-psychotics, anti-depressants and hypnotics, which resulted in little improvement. Donepezil administration dramatically improved his intractable delirium at the 19th post-donepezil administration day, but this was followed by amnestic symptoms. Clinical correlates of delirium with the basal forebrain lesion and efficacy of donepezil support the hypocholinergic theory of delirium.- - - - - - - - - - ranking = 3keywords = nucleus (Clic here for more details about this article) |
4/6. phacoemulsification in anterior megalophthalmos.This case outlines the phacoemulsification technique used to overcome the challenge of the hyperdeep anterior chamber, weak zonules, abnormal anterior capsule, and large capsular bag. Key steps included trypan blue staining of the anterior capsule, a large capsulorhexis, prolapse of the nucleus into the anterior chamber with phacoemulsification anterior to the capsulorhexis, and a posterior chamber-placed iris-clip intraocular lens. Successful visual rehabilitation is achievable in these anatomically challenging eyes.- - - - - - - - - - ranking = 1keywords = nucleus (Clic here for more details about this article) |
5/6. Behr syndrome: a clinicopathologic report.Two sisters had Behr syndrome; autopsy was performed on one. The autopsy revealed central atrophy of the optic nerves and total disarray of the normal laminar pattern of the lateral geniculate nucleus, dropout of neurons, and gliosis. There were numerous axonal spheroids in the neuropil. Similar spheroids with cell loss and gliosis were also observed in other thalamic nuclei and, rarely, in the pallida. We raise the possibility that Behr syndrome is a manifestation of a heterogeneous group of disorders, and suggest relationship of this particular disease to infantile neuroaxonal dystrophy.- - - - - - - - - - ranking = 1keywords = nucleus (Clic here for more details about this article) |
6/6. Congruous and incongruous sectoral visual field defects with lesions of the lateral geniculate nucleus.Quantitative perimetric studies in two women, each 52 years of age, with involvement of the lateral geniculate nucleus (caused by a small arteriovenous malformation in one and by an astrocytoma in the other) disclosed a striking wedge-shaped horizontal sectoranopia that was perfectly congruous in one case and incongruous in the other. Selective interruption of the dual blood supply to the lateral geniculate nucleus (with the anterior choroidal artery supplying the anterior hilus, together with the anterior and lateral nucleus and the lateral choroidal artery supplying the remainder of the nucleus) may result in a congruous visual field defect with steeply sloping borders because such a lesion must respect the anatomic boundaries produced by this vascular supply. Partial infiltration or involvement of the lateral geniculate nucleus (where uncrossed retinal projections terminate in one group of laminae, while crossed retinal projections terminate in another) provides a logical explanation for the occurrence of incongruous visual field defects. This unusual horizontal wedge-shaped defect should suggest lateral geniculate nucleus involvement, especially in the absence of trauma.- - - - - - - - - - ranking = 10keywords = nucleus (Clic here for more details about this article) |