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[en] The physiological mechanisms of deep brain stimulation (DBS) are not completely clear. Our understanding of them may be facilitated with the use of proton magnetic resonance spectroscopy (1H-MRS). Serial 1H-MRS of both thalami was performed during the course of DBS of bilateral globus pallidus internus in a patient with primary generalized dystonia. Two days after microelectrode implantation, a pulse frequency of 185 Hz was applied for stimulation. It resulted in relief of symptoms and a decrease of Burke-Fahn-Marsden dystonia rating scale (BFMDRS) scores, and was accompanied by a prominent increase of N-acetylaspartate (NAA)/choline-containing compounds (Cho) ratio, a mild increase of NAA/creatine (Cr) ratio, and a moderate decrease of Cho/Cr ratio. Two weeks later, for a search of the optimal stimulation mode, the pulse frequency was switched to 60 Hz, which resulted in clinical deterioration and significant increase of BFMDRS scores. At that time, all investigated 1H-MRS-detected metabolic parameters had nearly returned to the pretreatment levels. Use of serial 1H-MRS investigations of various brain structures during DBS in cases of movement disorders permits detailed evaluation of the treatment response, has a potential for its possible prediction, and may facilitate understanding of the physiological mechanisms of stimulation. (orig.)
[en] In the past six years, we have had experience with 40 patients with hypertensive thalamic hemorrhages, as verified by CT scan at our hospital within 24 hours. These patients were classified into the following three groups according to the location of the bleeding point and the size of the hematoma: (1) anteromedial (4 cases), (2) posterolateral (16 cases), and (3) massive (20 cases). The (1) and (2) hematomas were small (less than 3 cm in diameter), while those in (3) were large (more than 3 cm in diameter). Twenty cases (50% of all the thalamic hematomas) were small hematomas. The characteristic clinical symptoms of the anteromedial type were a mild disturbance of consciousness and thalamic dementia, while those of the posterolateral type were motor and sensory disturbance, and thalamic aphasia, respectively. Twenty cases (50%) were large hematomas. The clinical symptoms of these cases were mainly consciousness disturbance; 7 of them expired. Based on this experience, it may be considered that the patients whose hematoma size was larger than 3 cm had a poor prognosis and that the patients with the posterolateral type had a poor functional diagnosis. (author)
[en] The cerebral activation pattern due to acupuncture is not completely understood. Although the effect of acupuncture on cerebral haemodynamics has been studied, no previous report has focused on different puncture and stimulation methods. We used functional MRI (fMRI) in 15 healthy subjects to investigate cortical activation during stimulation of two real acupoints (Liv3 and G40) and one sham point, needled in a random and, for the subjects, blinded order employing rotating and non-rotating methods, using a blocked paradigm on a 1.5 tesla imager. Compared to the non-rotating stimulation method, during rotating stimulation of the real acupoints, we observed an increase in activation in both secondary somatosensory cortical areas, frontal areas, the right side of the thalamus and the left side of the cerebellum; no such effects of the needling technique were seen while stimulating the sham point. The observation that rotating the needle strengthened the effects of acupuncture only at real acupoints suggests that, as claimed in Chinese traditional medicine, stimulation of these acupoints has a specific effect on cortical neuronal activity, absent with sham acupoints. These specific cerebral activation patterns might explain the therapeutic effects of acupuncture in certain subjects. (orig.)
[en] There is described a rare case of the abscess localized in the left thalamus of dominant hemisphere of the brain. In case report with review of literature are emphasized advantages of the stereotactic method, which minimally invasively gives a possibility to aspirate even reaspirate abscess in this surgically inaccessible region if initial aspiration and antibiotic therapy proves ineffective. One year after surgery patient is without neurological deficit and follow up MR scans showed complete resolution of the lession. Application of MR methods is essential during diagnostic procedure and for evaluation of efficacy of selected treatment. Stereotactic aspiration is useful method in management of abscesses located in deep – seated or eloquent areas of the brain.
[en] Lysosomal disorders are rare and are caused by genetically transmitted lysosomal enzyme deficiencies. A decreased T2 signal in the thalamus has occasionally been reported. Because the finding of bilateral abnormal signal intensity of the thalamus on T2-weighted images has not been systematically reviewed, and its value as a diagnostic tool critically evaluated, we carried out a systematic review of the literature. Articles in English with 30 trios of keywords were collected from PubMed. Exclusion criteria were lack of conventional T2-weighted images in the protocol and not being a human study. Finally, 111 articles were included. The thalamus was considered affected only if mentioned in the text or in the figure legends. Some 117 patients with various lysosomal diseases and five patients with ceruloplasmin deficiency were reported to have a bilateral decrease in T2 signal intensity. At least one article reported a bilateral decrease in signal intensity of the thalami on T2-weighted images in association with GM1 and GM2 gangliosidosis and with Krabbe's disease, aspartylglucosaminuria, mannosidosis, fucosidosis, and mucolipidosis IV. Furthermore, thalamic alteration was a consistent finding in several types of neuronal ceroid lipofuscinosis (NCL) including CLN1 (infantile NCL), CLN2 (classic late infantile NCL), CLN3 (juvenile NCL), CLN5 (Finnish variant late infantile NCL), and CLN7 (Turkish variant late infantile NCL). A decrease in T2 signal intensity in the thalami seems to be a sign of lysosomal disease. (orig.)
[en] Non-surgical transfermoral embolization of centrally located huge intracerebral arteriovenous malformation (AVM) was successfully performed by using conventional 6.5F DAVIS II Catheter in the department of Radiology, Kangdong Sacred Heart Hospital, May 17, 1988. The large A.V.M. was located in left basal ganglia and thalamus on brain C.T. and was supplied by multiple dilated lateral lenticulostriate arteries from left middle cerebral artery and posterior thalamoperforating artery, posterior choroidal artery from left posterior cerebral artery angiographically. The AVM was partially obliterated after embolization of lateral lenticulostriate arteries and thalamoperforating artery with P.V.A. (Polyvinyl Alcohol, ivalon) using conventional 6.5F DAVIS II angiographic catheter. There was no complication which was related to those embolization procedures except transient drowsy consciousness after embolization but it is completely recovered to the level of preembolization state after 10 hours.
[en] The subjects studied in this report included 17 surgical cases which underwent evacuation of hematoma by means of BRW CT stereotaxic system approximately 14 days after its onset, and 11 non-operated cases. The average age was 65.5 years for the operated and 68.7 years for the non-operated groups. The neurological grades on admission were Grade III or above (slight or mild disturbance of consciousness). The evaluation of the cases was made according to (1) laterality of the hematoma on the left or right, (2) neurological grading, (3) maximum anterio-posterior, lateral diameters, and maximum depth of the hematoma, (4) CT classification (Kanaya, 1981) and ADL (5 grades) at 4.5 months after onset. No correlation was found between ADL and the laterality of the lesion in both groups. As for neurological grading I and ADL on admission, 6/8 cases in the operated and 3/8 in the nonoperated groups recovered to ADL grade 2 or above and 2 bed-ridden cases were included in the latter group. In regard to the extent of the hematoma, the mean ADL was 1.83 in the operated group. While 2.75 in the non-operated group where the hematoma was 25 mm or less in its maximum anterioposterior diameter. On CT, there existed a significant difference in ADL at IIb and 4/5 of the operated and 1/4 of the non-operated groups appeared to be ADL 2 or above. Assessment of the activities (mental change, willingness) as well as the muscle strength was performed within 3 days after surgery in operated group and 88.2 % and 35.3 % improvements were observed, respectively. One of the reasons for stereotaxic operation improving ADL seemed due to an early appearance of activity which leads to effective rehabilitation. (author)
[en] Nine patients with histologically confirmed germinomas of the basal ganglia and thalamus (GBT) were treated by radiotherapy. The average dose of 52.5 Gy was delivered to the tumor bed, 37 Gy to the whole brain and 24.8 Gy to the CNS axis. The local control, which was verified by CT scan, was achieved in all patients. All patients are alive 11 to 96 months after radiotherapy. As with other intracranial germinomas, germinomas of the basal ganglia and thalamus respond well to radiotherapy and the prognosis is good after treatment. (author). 20 refs., 1 fig., 1 tab
[en] Purpose: Elderly, high-risk surgical patients, may be unfit for radiofrequency thalamotomy for Parkinson's tremor. We have performed gamma knife radiosurgery in this select patient population, in lieu of open surgery, in an attempt at amelioration of disabling tremor. Materials and Methods: Radiosurgical nucleus ventralis intermedalis thalamotomy using gamma unit technique was performed on 38 patients (median age, 72 years; range: 50-88 years) over a period of 5 years. A median dose of 155 Gy (range: 110-160 Gy) was delivered using a single 4-mm collimator to 40 nuclei (2 patients underwent bilateral thalamotomy) using only anatomical atlas landmarks. The number of males and females were evenly divided, and their ages ranged from 50 to 88 years (median: 72 years). Two-thirds of the patients underwent left thalamotomy for right-sided trmor. Patients were followed-up for a median of 14 months (range: 6 to 43 months). Independent neurological evaluation of tremor as well as subjective patient evaluation were based on a 4-tiered scale: no improvement, mild improvement (0-33% effect), good improvement (33-66% effect), and excellent improvement (66-100%). Results: Eight thalamotomies (20%) failed, four (10%) gave mild improvement, and 28 (70%) gave good to excellent improvement of tremor (median time of onset of improvement was 3 months; range: 1-11 months). In 12 patients (32%) the tremor was eliminated completely. Concordance between independent neurologist evaluation and that of the patient was significant (p<0.001). Two patients in the failure group had an initial transient improvement. Two patients who underwent unilateral thalamotomy had bilateral improvement of their tremor. A permanent 5-6 mm lesion was seen on all follow-up MRIs and there were no radiological complications. A worsening of hand strength was seen in only patient. Conclusion: The safety and efficacy of gamma unit radiosurgical thalamotomy is on par with that of radiofrequency thalamotomy, and in a select surgical high-risk patient population, it may be the treatment choice
[en] We report specific changes bilaterally in the basal ganglia and thalamus following reperfusion after complete cerebral ischaemia. A 69-year-old man, resuscitated after cardiac arrest, showed symmetrical low-density lesions in the head of the caudate nucleus and lentiform nucleus on CT. MRI revealed methaemoglobin derived from minor haemorrhage in the basal ganglia and thalamus, not evident on CT. We suggest that this haemorrhage results from diapedesis of red blood cells through the damaged capillary endothelium following reperfusion. (orig.)