Toward an agreement on terminology of nuclear and subnuclear divisions of the motor thalamus

1997 ◽  
Vol 86 (4) ◽  
pp. 670-685 ◽  
Author(s):  
Giorgio Macchi ◽  
Edward G. Jones
Keyword(s):  
Nonhuman Primates ◽  
Experimental Studies ◽  
Medial Lemniscus ◽  
Nuclear Mass ◽  
Content Type ◽  
Human Thalamus ◽  
Human Motor ◽  
Motor Thalamus ◽  
Fine Print ◽  
Somatosensory Areas

✓ The nomenclature most commonly applied to the motor-related nuclei of the human thalamus differs substantially from that applied to the thalamus of other primates, from which most knowledge of input—output connections is derived. Knowledge of these connections in the human is a prerequisite for stereotactic neurosurgical approaches designed to alleviate movement disorders by the placement of lesions in specific nuclei. Transfer to humans of connectional information derived from experimental studies in nonhuman primates requires agreement about the equivalence of nuclei in the different species, and dialogue between experimentalists and neurosurgeons would be facilitated by the use of a common nomenclature. In this review, the authors compare the different nomenclatures and review the cyto- and chemoarchitecture of the nuclei in the anterolateral aspect of the ventral nuclear mass in humans and monkeys, suggest which nuclei are equivalent, and propose a common terminology. On this basis, it is possible to identify the nuclei of the human motor thalamus that transfer information from the substantia nigra, globus pallidus, cerebellum, and proprioceptive components of the medial lemniscus to prefrontal, premotor, motor, and somatosensory areas of the cerebral cortex. It also becomes possible to suggest the principal functional systems involved in stereotactically guided thalamotomies and the functional basis of the symptoms observed following ischemic lesions in different parts of the human thalamus.

Toward an agreement on terminology of nuclear and subnuclear divisions of the motor thalamus

1997 ◽  
Vol 86 (1) ◽  
pp. 77-92 ◽  
Author(s):  
Giorgio Macchi ◽  
Edward G. Jones
Keyword(s):  
Nonhuman Primates ◽  
Experimental Studies ◽  
Medial Lemniscus ◽  
Nuclear Mass ◽  
Content Type ◽  
Human Thalamus ◽  
Human Motor ◽  
Motor Thalamus ◽  
Fine Print ◽  
Somatosensory Areas

✓ The nomenclature most commonly applied to the motor-related nuclei of the human thalamus differs substantially from that applied to the thalamus of other primates, from which most knowledge of input—output connections is derived. Knowledge of these connections in the human is a prerequisite for stereotactic neurosurgical approaches designed to alleviate movement disorders by the placement of lesions in specific nuclei. Transfer to humans of connectional information derived from experimental studies in nonhuman primates requires agreement about the equivalence of nuclei in the different species, and dialogue between experimentalists and neurosurgeons would be facilitated by the use of a common nomenclature. In this review, the authors compare the different nomenclatures and review the cyto- and chemoarchitecture of the nuclei in the anterolateral aspect of the ventral nuclear mass in humans and monkeys, suggest which nuclei are equivalent, and propose a common terminology. On this basis, it is possible to identify the nuclei of the human motor thalamus that transfer information from the substantia nigra, globus pallidus, cerebellum, and proprioceptive components of the medial lemniscus to prefrontal, premotor, motor, and somatosensory areas of the cerebral cortex. It also becomes possible to suggest the principal functional systems involved in stereotactically guided thalamotomies and the functional basis of the symptoms observed following ischemic lesions in different parts of the human thalamus.

Induction of glioblastoma multiforme in nonhuman primates after therapeutic doses of fractionated whole-brain radiation therapy

2002 ◽  
Vol 97 (6) ◽  
pp. 1378-1389 ◽  
Author(s):  
Russell R. Lonser ◽  
Stuart Walbridge ◽  
Alexander O. Vortmeyer ◽  
Svetlana D. Pack ◽  
Tung T. Nguyen ◽  
...  
Keyword(s):  
Radiation Therapy ◽  
Glioblastoma Multiforme ◽  
Mr Imaging ◽  
Nonhuman Primates ◽  
Molecular Analyses ◽  
Content Type ◽  
Whole Brain Radiation ◽  
Brain Radiation ◽  
Fine Print

Object. To determine the acute and long-term effects of a therapeutic dose of brain radiation in a primate model, the authors studied the clinical, laboratory, neuroimaging, molecular, and histological outcomes in rhesus monkeys that had received fractionated whole-brain radiation therapy (WBRT). Methods. Twelve 3-year-old male primates (Macaca mulatta) underwent fractionated WBRT (350 cGy for 5 days/week for 2 weeks, total dose 3500 cGy). Animals were followed clinically and with laboratory studies and serial magnetic resonance (MR) imaging. They were killed when they developed medical problems or neurological symptoms, lesions appeared on MR imaging, or at study completion. Gross, histological, and molecular analyses were then performed. Nine (82%) of 11 animals that underwent long-term follow up (> 2.5 years) developed neurological symptoms and/or enhancing lesions on MR imaging, which were defined as glioblastoma multiforme (GBM), 2.9 to 8.3 years after radiation therapy. The GBMs were categorized as either unifocal (three) or multifocal (six), and were located in the supratentorial (six), infratentorial (two), or both (one) cranial regions. Histological examination revealed distant, noncontiguous tumor invasion within the white matter of all nine animals harboring GBMs. Novel interspecies comparative genomic hybridization (three animals) uniformly showed deletions in the GBMs that corresponded to chromosome 9 in humans. Conclusions. The high rate of GBM formation (82%) following a therapeutic dose of WBRT in nonhuman primates indicates that radioinduction of these neoplasms as a late complication of this therapy may occur more frequently than is currently recognized in human patients. The development of these tumors while monitoring the monkeys' conditions with clinical and serial MR imaging studies, and access to the tumor and the entire brain for histological and molecular analyses offers an opportunity to gather unique insights into the nature and development of GBMs.

Madreporic coral: a new bone graft substitute for cranial surgery

1988 ◽  
Vol 69 (4) ◽  
pp. 510-513 ◽  
Author(s):  
François X. Roux ◽  
Daniel Brasnu ◽  
Bernard Loty ◽  
Bernard George ◽  
Geneviève Guillemin
Keyword(s):  
Bone Graft ◽  
Reconstructive Surgery ◽  
Experimental Studies ◽  
Bone Graft Substitute ◽  
Biological Properties ◽  
Content Type ◽  
Skull Defects ◽  
Cranial Fossa ◽  
Burr Holes ◽  
Fine Print

✓ Since 1985, the authors have been using madreporic coral fragments (genera Porites) as a bone graft substitute. Of the 167 coral grafts implanted, 150 were coral “corks” used to obliterate burr holes (diameter 10 mm), five were large implants (length 20 to 40 mm) to repair skull defects, and 12 were coral blocks to reconstruct the floor of the anterior cranial fossa. Previous experimental studies suggested that coral grafts would be well tolerated and become partially reossified as the calcific skeleton was resorbed. The authors describe their experience and detail the main biological properties of these materials, which appear to be very promising for use in cranial reconstructive surgery.

Effects of timing of methylprednisolone or naloxone administration on recovery of segmental and long-tract neurological function in NASCIS 2

1993 ◽  
Vol 79 (4) ◽  
pp. 500-507 ◽  
Author(s):  
Michael B. Bracken ◽  
Theodore R. Holford
Keyword(s):  
Clinical Management ◽  
Experimental Studies ◽  
Neurological Function ◽  
Neurological Recovery ◽  
Content Type ◽  
Naloxone Administration ◽  
Delayed Treatment ◽  
Cord Injury ◽  
Neurological Response ◽  
Fine Print

✓ Previous analyses of the National Acute Spinal Cord Injury Study (NASCIS) have not distinguished recovery of segmental function at the injury level from recovery of the long spinal tracts. Recovery at the injury level could be of considerable clinical significance, but long-tract recovery is the ultimate therapeutic goal. This analysis demonstrates that the greatest proportion of all neurological recovery and of recovery due to treatment with very high doses of methylprednisolone within 8 hours of injury occurs below the lesion. Methylprednisolone treatment administered early following injury has been found to improve recovery below the lesion in patients initially diagnosed as having complete or incomplete injuries; it also leads to greater (but still relatively small) improvement in the injury level. The analysis indicates that delayed treatment with methylprednisolone is associated with decreased neurological recovery. Naloxone administration also improved neurological function below the lesion in patients with incomplete injuries; these results support further experimental work with this drug. This observation of differential neurological response within a narrow treatment window has important implications for both experimental studies and clinical management. Early clinical management with highdose methylprednisolone is supported by this analysis.

Decrease in platelet count as an independent risk factor for symptomatic vasospasm following aneurysmal subarachnoid hemorrhage

2005 ◽  
Vol 102 (5) ◽  
pp. 882-887 ◽  
Author(s):  
Yutaka Hirashima ◽  
Hideo Hamada ◽  
Masanori Kurimoto ◽  
Hideki Origasa ◽  
Shunro Endo
Keyword(s):  
Platelet Count ◽  
Subarachnoid Hemorrhage ◽  
Blood Cells ◽  
White Blood Cells ◽  
Experimental Studies ◽  
Content Type ◽  
Symptomatic Vasospasm ◽  
Cell Counts ◽  
Fisher Grade ◽  
Fine Print

Object. Increased platelet consumption is expected in patients with cerebral vasospasm, according to data from clinical and experimental studies. The authors investigated sequential changes in platelet counts in patients with subarachnoid hemorrhage (SAH) and the difference in platelet consumption between patients with and those without symptomatic vasospasm (SV). Variables related to platelet count as well as other clinical and radiological variables were analyzed as independent predictors of SV. Methods. One hundred consecutive patients who had undergone surgery within 48 hours after SAH onset were entered in the study. Clinical and radiological variables and blood cell counts, including red blood cells, white blood cells, and platelets, after SAH were retrospectively examined. Twenty of these variables were entered into univariate and multivariate analyses to determine predictors for SV. After SAH, the platelet count decreased to a minimum and then increased rapidly to levels greater than those recorded on admission. This change was specific to SAH, and platelet consumption was more severe in patients with SV than in those without. There were three independent predictors of SV: a ratio of the lowest platelet count and the admission count greater than 0.7 (odds ratio [OR] 0.322, 95% confidence interval [CI] 0.124–0.834, p = 0.0196) and a history of hypertension (OR 0.338, 95% CI 0.126–0.906, p = 0.0311) were negatively significant (that is, decreases the occurrence of SV), and a Fisher Grade 3 (OR 4.42, 95% CI 1.48–13.2, p = 0.0077) was positively significant (that is, increases the occurrence of SV). Conclusions. The association between a decrease in platelet count and the occurrence of SV indicates the important role of platelets in the pathophysiology of vasospasm following SAH.

History of spinal cord stereotaxy

1996 ◽  
Vol 85 (4) ◽  
pp. 725-731 ◽  
Author(s):  
Eric M. Gabriel ◽  
Blaine S. Nashold
Keyword(s):  
Spinal Cord ◽  
Clinical Practice ◽  
Spinal Fusion ◽  
Spinal Surgery ◽  
Experimental Studies ◽  
Functional Neurosurgery ◽  
Content Type ◽  
Anatomy And Physiology ◽  
History Of ◽  
Fine Print

✓ Stereotactic and functional neurosurgery has experienced a remarkable degree of development during the last 50 years, from the plaster of Paris frame of Spiegel and Wycis to the technology of frameless stereotaxis. Although predominantly used for intracranial procedures, stereotaxy has its roots in experimental studies of the spinal cord. The field of spinal cord stereotaxy has not received the same amount of attention as supratentorial surgery, but there have been significant contributions to the field that have helped to further our understanding of spinal cord anatomy and physiology. Now that frameless stereotaxis has reached clinical practice, there may be further developments in the field of spinal surgery: this technique may prove useful for spinal fusion operations and, possibly, intramedullary operations as well.

Prevention of cerebral vasospasm by a humanized anti-CD11/CD18 monoclonal antibody administered after experimental subarachnoid hemorrhage in nonhuman primates

2003 ◽  
Vol 99 (2) ◽  
pp. 376-382 ◽  
Author(s):  
Richard E. Clatterbuck ◽  
Philippe Gailloud ◽  
Lynn Ogata ◽  
Abeyu Gebremariam ◽  
Gregory N. Dietsch ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Subarachnoid Hemorrhage ◽  
Cerebral Vasospasm ◽  
Subarachnoid Space ◽  
Nonhuman Primates ◽  
Leukocyte Migration ◽  
Content Type ◽  
Areal Fraction ◽  
Chronic Vasospasm ◽  
Fine Print

Object. Leukocyte—endothelial cell interactions occurring in the first hours after subarachnoid hemorrhage (SAH) initiate changes in the endothelium and vessel wall that lead to an influx of leukocytes and the development of chronic vasospasm days later. Upregulation of intercellular adhesion molecule—1 (ICAM-1), also called CD54, appears to be a crucial step in this process. There is increasing experimental evidence that blocking the interaction between ICAM-1, which is expressed on endothelium, and integrins such as lymphocyte function—associated antigen—1 (CD11a/CD18) and macrophage antigen—1 (complement receptor 3, CD11b/CD18), which are expressed on the surface of leukocytes, prevents not only inflammation of vessel walls but also chronic vasospasm. The authors extend their previous work with monoclonal antibody (mAb) blockade of leukocyte migration to a nonhuman primate model of chronic, posthemorrhagic cerebral vasospasm. Methods. Before surgery was performed, six young adult male cynomolgus monkeys underwent baseline selective biplane common carotid and vertebrobasilar artery cerebral angiography via a transfemoral route. On Day 0, a right frontosphenotemporal craniectomy was performed with arachnoid microdissection and placement of 2 to 3 ml of clotted autologous blood in the ipsilateral basal cisterns. The animals were given daily intravenous infusions of 2 mg/kg of either a humanized anti-CD11/CD18 or a placebo mAb beginning 30 to 60 minutes postoperatively. The monkeys were killed on Day 7 after a repeated selective cerebral angiogram was obtained. The area of contrast-containing vessels observed in each hemisphere on anteroposterior angiographic views was calculated for the angiograms obtained on Day 7 and expressed as a percentage of the area on baseline angiograms (percent control areal fraction). Review of flow cytometry and enzyme immunoassay data confirmed the presence of the anti-CD11/CD18 antibody in the serum and bound to leukocytes in the peripheral blood of treated animals. Comparisons of the groups revealed 53 ± 4.8% control vascular areal fraction in the placebo group (two animals) and 95.8 ± 9.4% in the anti-CD11/CD18—treated group (three animals), a statistically significant difference (p = 0.043, t-test). Conclusions. These results show that blockade of leukocyte migration into the subarachnoid space by an anti-CD11/CD18 mAb is effective in preventing experimental cerebral vasospasm in nonhuman primates, despite the unaltered presence of hemoglobin in the subarachnoid space. These experimental data support the hypothesis that inflammation plays a role in cerebral vasospasm after SAH.

The effects of prostaglandins E1, A1, and F2a on the cerebral circulation of dogs and monkeys

1972 ◽  
Vol 36 (1) ◽  
pp. 34-42 ◽  
Author(s):  
Ira C. Denton ◽  
Richard P. White ◽  
James T. Robertson
Keyword(s):  
Cerebral Circulation ◽  
Experimental Studies ◽  
The Other ◽  
Prostaglandin E ◽  
Perfusion Technique ◽  
Content Type ◽  
Selective Increase ◽  
Intracarotid Administration ◽  
Specific Influence ◽  
Fine Print

✓ Alterations in cerebrovascular tone caused by the intracarotid administration of prostaglandin E1, A1, and F2a were evaluated by means of a standard perfusion technique in dogs and monkeys. Only PGF2a evoked a selective increase in cerebrovascular tone. This effect was observed in both species and resembled the action of serotonin. On the other hand, prostaglandin E1 selectively reduced cerebrovascular tone in dogs, but had no such specific action in the monkey. Prostaglandin A1 lacked a specific influence on the cerebral circulation of either species. Since different prostaglandins produced specific and diametrically opposite effects on cerebral circulation, these substances may be useful in experimental studies of vasospasm, and may normally influence cerebrovascular tone.

The effect of brain temperature on hemoglobin extravasation after traumatic brain injury

2002 ◽  
Vol 97 (4) ◽  
pp. 945-953 ◽  
Author(s):  
Kosaku Kinoshita ◽  
Katina Chatzipanteli ◽  
Ofelia F. Alonso ◽  
Mackenzie Howard ◽  
W. Dalton Dietrich
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Injury Severity ◽  
Brain Temperature ◽  
Experimental Studies ◽  
Hemoglobin Concentration ◽  
Contralateral Hemisphere ◽  
Ipsilateral Hemisphere ◽  
Content Type ◽  
Fine Print

Object. Although the benefits of posttraumatic hypothermia have been reported in experimental studies, the potential for therapeutic hypothermia to increase intracerebral hemorrhage remains a clinical concern. The purpose of this study was to quantify the amount of extravasated hemoglobin after traumatic brain injury (TBI) and to assess the changes in intracerebral hemoglobin concentrations under posttraumatic hypothermic and hyperthermic conditions. Methods. Intubated and anesthetized rats were subjected to fluid-percussion injury (FPI). In the first experiment, rats were divided into moderate (1.8–2.2 atm) and severe (2.4–2.7 atm) TBI groups. In the second experiment, the effects of 3 hours of posttraumatic hypothermia (33 or 30°C), hyperthermia (39°C), or normothermia (37°C) on hemoglobin levels following moderate trauma were assessed. The rats were perfused with saline at 24 hours postinjury, and then the traumatized and contralateral hemispheres, including the cerebellum, were dissected from whole brain. The hemoglobin level in each brain was quantified using a spectrophotometric hemoglobin assay. The results of these assays indicate that moderate and severe FPI induce increased levels of hemoglobin in the ipsilateral hemisphere (p < 0.0001). After severe TBI, the hemoglobin concentration was also significantly increased in the contralateral hemisphere (p < 0.05) and cerebellum (p < 0.005). Posttraumatic hypothermia (30°C) attenuated hemoglobin levels (p < 0.005) in the ipsilateral hemisphere, whereas hyperthermia had a marked adverse effect on the hemoglobin concentration in the contralateral hemisphere (p < 0.05) and cerebellum (p < 0.005). Conclusions. Injury severity is an important determinant of the degree of hemoglobin extravasation after TBI. Posttraumatic hypothermia reduced hemoglobin extravasation, whereas hyperthermia increased hemoglobin levels compared with normothermia. These findings are consistent with previous data reporting that posttraumatic temperature manipulations alter the cerebrovascular and inflammatory consequences of TBI.

Tremor cells in the human thalamus: differences among neurological disorders

2004 ◽  
Vol 101 (1) ◽  
pp. 43-47 ◽  
Author(s):  
Jason A. Brodkey ◽  
Ronald R. Tasker ◽  
Clement Hamani ◽  
Mary Pat McAndrews ◽  
Jonathan O. Dostrovsky ◽  
...  
Keyword(s):  
Neurological Disorders ◽  
Critical Role ◽  
Thalamic Nuclei ◽  
Related Activity ◽  
Content Type ◽  
Pathological Conditions ◽  
Human Thalamus ◽  
Patient Groups ◽  
Cerebellar Disorders ◽  
Fine Print

Object. Thalamic neurons firing at frequencies synchronous with tremor are thought to play a critical role in the generation and maintenance of tremor. The authors studied the incidence and locations of neurons with tremor-related activity (TRA) in the thalamus of patients with varied pathological conditions—including Parkinson disease (PD), essential tremor (ET), multiple sclerosis (MS), and cerebellar disorders—to determine whether known differences in the effectiveness of thalamic stereotactic procedures for these tremors could be correlated to differences in the incidence or locations of TRA cells. Methods. Seventy-five operations were performed in 61 patients during which 686 TRA cells were recorded from 440 microelectrode trajectories in the thalamus. The locations of the TRA cells in relation to electrophysiologically defined thalamic nuclei and the commissural coordinates were compared among patient groups. The authors found that TRA cells are present in patients with each of these disorders and that these cells populate several nuclei in the ventral lateral tier of the thalamus. There were no large differences in the locations of TRA cells among the different diagnostic classes, although there was a difference in the incidence of TRA cells in patients with PD, who had greater than 3.8 times more cells per thalamic trajectory than patients with ET and approximately five times more cells than patients with MS or cerebellar disorders. Conclusions. There was an increased incidence of TRA in the thalamus of patients with PD. The location of thalamic TRA cells in patients with basal ganglia and other tremor disorders was similar.

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