1/22. A case of thalamic syndrome: somatosensory influences on visual orientation.The ability to set a straight line to the perceived gravitational vertical (subjective visual vertical, SVV) was investigated in a 21 year old woman with long standing left hemihypaesthesia due to a posterior thalamic infarct. The putative structures involved were the somatosensory and vestibular thalamus (VPL, VPM) and associative (pulvinar) thalamus. The SVV was normal when seated upright. When lying on her right side, line settings deviated about 17 degrees to the right, which is the normal A-effect. When lying on the hypaesthetic side the mean SVV remained close to true vertical-that is, the A-effect was absent, and there was a large increase in variability of the SVV settings. The findings support the view that the body tilt-induced bias of the SVV (A-effect) is largely mediated by somatosensory afferents. The finding that the A-effect was absent only when lying on the hypaesthetic side suggests that, during body tilt, the somatosensory system participates in visuogravitational orientation.- - - - - - - - - - ranking = 1keywords = vertical (Clic here for more details about this article) |
2/22. Correlation of clinical and neuroradiological findings in down-gaze palsy.BACKGROUND: Isolated down-gaze palsy is the least common pathology of vertical gaze. patients with low-gaze palsy may consult an ophthalmologist with difficulty in reading and this may be the only ocular finding of a central nervous system lesion. methods: A 43-year-old man with isolated down-gaze palsy was examined. The medical history of the patient revealed that he had had myocardial infarction. RESULT: magnetic resonance imaging disclosed an ischemic area at the right thalamus. CONCLUSION: Down-gaze palsy may be an important sign for the diagnosis of thalamic infarctions due to embolic syndrome.- - - - - - - - - - ranking = 0.33333333333333keywords = vertical (Clic here for more details about this article) |
3/22. Monocular central dazzle after thalamic infarcts.The authors observed a patient after he had ischemic strokes in both paramedian thalamic regions, which were more marked on the left side. Symptoms included dysphasia, vertical binocular diplopia, right-sided hemianopia, and a right-sided sensory and motor deficit, sparing the face. However, the most disturbing phenomenon was a painless, left monocular dazzle, which was the presenting symptom and also the only persisting symptom. This report shows that a thalamic lesion may be at the origin of central dazzle, and to the authors' knowledge, it is the first clinical observation of its monocular occurrence. It is conceivable that this dazzle was due to optic-trigeminal summation.- - - - - - - - - - ranking = 0.33333333333333keywords = vertical (Clic here for more details about this article) |
4/22. Unilateral thalamic infarction and vertical gaze palsy: cause or coincidence?Although vertical gaze palsy (VGP) is commonly associated with lesions of the rostral mesencephalon, there is some evidence that VGP may also be caused by a unilateral thalamic lesion. The case of a 68-year-old man with persistent upward gaze palsy after a unilateral thalamic infarction, demonstrated on computed tomography and magnetic resonance imaging scans, is presented. Subsequent high-resolution magnetic resonance scanning, however, showed involvement of the rostral mesencephalon as well. The authors suggest that in previous patients with VGP ascribed to a unilateral thalamic infarction, a coexisting mesencephalic involvement may have been missed because of inappropriate imaging techniques. Strong evidence of unilateral thalamic infarction as a cause of VGP is still lacking.- - - - - - - - - - ranking = 1.6666666666667keywords = vertical (Clic here for more details about this article) |
5/22. Total recovery after bilateral paramedian thalamic infarct.Bilateral paramedian thalamic infarcts are characterised initially by the association of acute vigilance disorders and vertical gaze palsy, followed by persisting dementia with severe mnemic disturbance, global aspontaneity and apathy. We describe a patient with a dramatic neuropsychological recovery, confirmed by testing examination and completed by a cerebral metabolism study. The pathophysiology of this type of cognitive deficit is discussed.- - - - - - - - - - ranking = 0.33333333333333keywords = vertical (Clic here for more details about this article) |
6/22. Paramedian thalamopeduncular infarction: clinical syndromes and magnetic resonance imaging.We prospectively examined 11 patients with magnetic resonance imaging-documented infarction in the paramedian thalamopeduncular region, which is supplied by the superior mesencephalic and posterior thalamosubthalamic arteries. Variations in the size and rostral-caudal extent of infarction correlated with the following three clinical patterns: (1) With unilateral paramedian mesencephalic infarction, an ipsilateral third nerve paresis was accompanied by mild contralateral hemiparesis or hemiataxia. Contralateral ptosis and impaired upgaze were observed in two patients; one of them showed additional damage to the posterior commissure. (2) With bilateral infarction in the thalamopeduncular junction, involving the mesencephalic reticular formation, supranuclear vertical gaze defects were accompanied by impaired consciousness or memory, and mild aphasia in some patients. Persistent amnesia was observed only when the dominant anterior nucleus or mamillothalamic tract was damaged. (3) With larger thalamopeduncular infarcts, partial or complete third nerve paresis was combined with supranuclear gaze disturbance and delayed contralateral tremor. An unusual gaze disorder, a variant of the vertical "one-and-a-half syndrome," occurred with a small strategically placed lesion at the thalamopeduncular junction, best explained by selective damage to supranuclear pathways or partial nuclear involvement. The primary cause of these infarctions was embolism to the basilar apex or local atheroma at the origin of the posterior cerebral artery.- - - - - - - - - - ranking = 0.66666666666667keywords = vertical (Clic here for more details about this article) |
7/22. Dissociated unilateral convergence paralysis in a patient with thalamotectal haemorrhage.A 47 year old male was admitted in a comatose state. CT scan showed a haemorrhage in the right pulvinar thalamus descending into the right part of the lamina quadrigemina. He presented with anisocoria, prompt bilateral pupillary light reaction, and unilateral convergence paralysis contralateral to the lesion in combination with upward gaze palsy. During an observation period of two months, the convergence reaction returned to normal. MRI showed a lacunar lesion ventral to superior right colliculus. angiography revealed an arteriovenous malformation (right posterior cerebral artery--sinus rectus) as the possible cause of the haemorrhage.- - - - - - - - - - ranking = 70.985979628653keywords = convergence (Clic here for more details about this article) |
8/22. Hypersexuality and dysexecutive syndrome after a thalamic infarct.Hypersexuality can result from insults to several neuroanatomical structures that regulate sexual behavior. A case is presented of an adult male with a thalamic infarct resulting in a paramedian thalamic syndrome, consisting of hypersomnolence, confabulatory anterograde amnesia (including reduplicative paramnesia), vertical gaze deficits, and hypophonic speech. A dysexecutive syndrome also manifested, consisting of social disinhibition, apathy, witzelsucht, motor inhibition deficits, and environmental dependence. Hypersexuality uncharacteristic of his premorbid behavior was evident in instances of exhibitionism, public masturbation, and verbal sexual obscenities. In contrast to the few previous reports of hypersexuality following thalamic infarct, this case neither involved mania nor hemichorea. The relevance of the mediodorsal thalamic nucleus in limbic and prefrontal circuits is discussed.- - - - - - - - - - ranking = 0.33333333333333keywords = vertical (Clic here for more details about this article) |
9/22. Transient vertical diplopia and nystagmus associated with acute thalamic infarction.We describe a patient who presented with a 1-h history of vertical diplopia and nystagmus and was found to have acute left ventrolateral thalamic infarction on the diffusion-weighted magnetic resonance imaging (DWI MRI). This is the first case report demonstrating that vertical diplopia and nystagmus, which typically suggest a lesion in the brainstem or cerebellum, may also occur in acute thalamic infarction. DWI MRI can detect thalamic infarction as early as 1 h after its clinical manifestations.- - - - - - - - - - ranking = 131.06204386835keywords = nystagmus, vertical (Clic here for more details about this article) |
10/22. stroke involving the midbrain and thalamus and causing 'nonfocal' coma.We have described two patients who had coma without focal findings and who were found to have an ischemic stroke involving the midbrain and the thalamus. In both cases metabolic encephalopathy or drug overdose was initially suspected, but recognition of abnormal vertical eye movements led to the proper diagnosis. Examination of vertical eye movements in drowsy or comatose patients may be helpful in arriving at the correct diagnosis early and may prevent unnecessary investigations.- - - - - - - - - - ranking = 0.66666666666667keywords = vertical (Clic here for more details about this article) |
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