1/309. Bilateral enhancing thalamic lesions in a 10 year old boy: case report. A young boy presented with monoparesis of the left arm. MRI disclosed bilateral enhancing thalamic lesions. biopsy results and subsequent clinical history were most compatible with postinfectious or acute disseminated encephalomyelitis. This represents one of the first cases of acute disseminated encephalomyelitis affecting the thalami, established by biopsy. This uncommon disease entity is reviewed and how it may affect the deep grey matter is described. ( info) |
2/309. Thalamic hemorrhage following carotid endarterectomy-induced labile blood pressure: controlling the liability with clonidine--a case report. Carotid endarterectomy can lead to alterations in baroreceptor sensitivity. Impairment of this sensitivity can in turn lead to volatility of blood pressure (baroreflex failure syndrome--BFS). Rapid elevations in blood pressure can cause hypertensive encephalopathy in a patient with BFS. A patient is presented with hypertensive intracerebral hemorrhage associated with BFS. ( info) |
| The effects of conditioning stimulation of an upper limb on motor evoked potentials (MEPs) of relaxed muscles in both lower limbs were studied in 7 normal subjects and two patients with left thalamic infarction. A possible mechanism for the Jendrassik maneuver (JM) is that induced proprioceptive input ascends supraspinally to facilitate the descending volleys. In order to mimic the JM with a more controlled influence, we used an electrical conditioning (C) stimulation (4 times sensory threshold) delivered to the left index finger preceding the transcranial (T) magnetic stimulation at C-T intervals of 0-200 ms. The MEP facilitation of bilateral tibialis anterior (TA) and gastrocnemius medialis (GC) was within C-T 70-110 ms. The peak facilitation was at C-T 80 ms for ipsilateral TA (309%) and GC (405%) and at C-T 90 ms for contralateral TA (207%) and GC (283%). In the two thalamic infarction patients with right-sided sensory loss, the facilitation did not occur when the conditioning stimulation was delivered to the affected index finger. Therefore, it is likely that the peripheral volley must be transmitted supraspinally to facilitate MEPs of the lower limbs. This method for studying sensory facilitation is more quantitative and reproducible than the JM and technically better than other previously described methods for somatosensory conditioning. ( info) |
4/309. MR spectroscopy of bilateral thalamic gliomas. This study reports the MR spectroscopic patterns of two patients with bithalamic glioma. In one patient, phosphorus (31P) MR spectroscopy was performed. In both patients, the proton MR spectroscopic scans showed an increased creatine-phosphocreatine peak in the tumor. In the patient who underwent 31P-MR spectroscopy, an increased phosphocreatine peak was also observed. This group of thalamic tumors may be distinguished from other gliomas clinically, radiologically, and metabolically. ( info) |
5/309. 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. ( info) |
6/309. Bilateral thalamic pain secondary to bilateral thalamic infarcts relieved by a further unilateral ischaemic episode. This study reports a patient with severe, debilitating bilateral thalamic pain caused by bilateral thalamic infarcts. The authors consider it to be a unique case as a further clinically unilateral lesion led to pain relief bilaterally. ( info) |
| A 72-year-old woman experienced a sudden onset of spontaneous tremor and myoclonus of right extremities that completely subsided 24 hours after onset. neuroimaging study revealed an infarct at the left ventral portion of thalamus and subthalamic nucleus. Concomitant dyskinetic movement disorders after stroke are extremely rare and the mechanism is herein discussed. ( info) |
8/309. Motor neglect following left thalamic hemorrhage: a case report. We present a report on a patient who developed unilateral motor neglect of the right hemibody after a left thalamic hemorrhage. He presented with pure motor neglect without aphasia, ideomotor apraxia, or unilateral spatial neglect due to a lesion in the centromedian parafascicular (CMPF) and ventrolateral (VL) nuclei of the left thalamus. Although unilateral motor neglect is usually associated with right hemispheric lesions, a left thalamic lesion may also result in isolated motor neglect. ( info) |
9/309. Simultaneous bilateral thalamic hemorrhage: case report. A 60-year-old man presented with an extremely rare case of simultaneous hypertensive bilateral thalamic hemorrhage manifesting as left hemiparesis with headache followed by deterioration in consciousness and tetraparesis. CT scan confirmed the bilateral thalamic hemorrhages 17 hours after onset. magnetic resonance imaging showed the bilateral thalamic lesions had similar signal intensities, consistent with the simultaneous onset, and had no evidence of hemorrhagic reason. Conservative treatment achieved some neurological improvement, but he died of pneumonia six months after onset. The prognosis of a patient with bilateral hemorrhages is worse than would be indicated by the size of the hemorrhages. ( info) |
10/309. The stereotactic volumetric information: its role in two-step resection of brainstem and thalamic giant tumor. Report of three cases and technical note. BACKGROUND: A compact intracerebral tumoral lesion is usually considered to be completely resectable. Nevertheless, radical resection of a huge lesion located in a critical area may damage the surrounding compressed brain tissue. In cases with a good prognosis, a two-step removal appears to be a safer strategy. methods: In three cases, two with huge brain stem lesions and one with a thalamic lesion, a two-step volumetric stereotactic resection was planned. This strategy allowed us to evaluate the amount of tumor to be removed during the first procedure and to have, during the second operation, an exact definition of the reduced mass with regard to the scar tissue and postoperative adhesions. Furthermore, we avoided significant shifting of the cerebral structures during both procedures. RESULTS: There was a very good final recovery in the cases with brain stem lesions and a minimal deficit in the patient with the thalamic lesion. The patient with a mesencephalic lesion remained comatose for almost 2 days after the first procedure, confirming our fears about too radical a one-step resection. CONCLUSIONS: We think that by using current techniques, it is possible to remove a well circumscribed lesion regardless of its position. This is probably easier with giant lesions where a safe trajectory can be planned. In these cases, with lesions located in very critical areas but with a good prognosis, a two-step resection appears to be a good option. ( info) |