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Charles H. Tator and Izumi Koyanagi

traumatized spinal cord in rats, 20, 21, 34, 45 cats, 1, 5, 7, 31 rabbits, 8, 27, 44 and monkeys. 11 The pathophysiology of vascular mechanisms of secondary neural injury was the topic of a recent review. 37 In the present study, we investigated the vascular system in three uninjured human cervical spinal cords using silicone rubber microangiography. This technique allows three-dimensional analysis of the intramedullary vessels after the spinal cord is made transparent with an alcohol—methylsalicylate technique. 21 The present study is the first to use this technique

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Charles H. Tator and Izumi Koyanagi

Vascular injury plays an important role in the primary and secondary injury mechanisms that cause damage to the acutely traumatized spinal cord. To understand the pathophysiology of human spinal cord injury, the authors investigated the vascular system in three uninjured human spinal cords using silicone rubber microangiography and analyzed the histological findings related to vascular injury in nine acutely traumatized human spinal cords obtained at autopsy. The interval from spinal cord injury to death ranged from 20 minutes to 9 months. The microangiograms of the uninjured human cervical cords demonstrated new information about the sulcal arterial system and the pial arteries. The centrifugal sulcal arterial system was found to supply all of the anterior gray matter, the anterior half of the posterior gray matter, approximately the inner half of the anterior and lateral white columns, and the anterior half of the posterior white columns. Traumatized spinal cord specimens in the acute stage (3-5 days postinjury) showed severe hemorrhages predominantly in the gray matter, but also in the white matter. The white matter surrounding the hemorrhagic gray matter showed a variety of lesions, including decreased staining, disrupted myelin, and axonal and periaxonal swelling. The white matter lesions extended far from the injury site, especially in the posterior columns. There was no evidence of complete occlusion of any of the larger arteries, including the anterior and posterior spinal arteries and the sulcal arteries. However, occluded intramedullary veins were identified in the degenerated posterior white columns. In the chronic stage (3-9 months postinjury), the injured segments showed major tissue loss with large cavitations, whereas both rostral and caudal remote sites showed well-demarcated necrotic areas indicative of infarction mainly in the posterior white columns. Obstruction of small intramedullary arteries and veins by the initial mechanical stress or secondary injury mechanisms most likely produced these extensive white matter lesions. Our studies implicate damage to the anterior sulcal arteries in causing the hemorrhagic necrosis and subsequent central myelomalacia at the injury site in acute spinal cord injury in humans.

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Neurosurgical Forum: Letters to the Editor To The Editor Michael A. Rie , M.D. Brenda G. Fahy , M.D., F.C.C.M. University of Kentucky Medical Center Lexington, Kentucky W. Andrew Kofke , M.D., M.B.A., F.C.C.M. Hospital of the University of Pennsylvania Philadelphia, Pennsylvania 564 566 Abstract Object. Human albumin is used to induce hypervolemia (central venous pressure [CVP] > 8 mm Hg) after subarachnoid hemorrhage (SAH). Unfortunately, human albumin may increase the

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Neurosurgical Forum: Letters to the Editor To The Editor Michael A. Rie , M.D. Brenda G. Fahy , M.D., F.C.C.M. University of Kentucky Medical Center Lexington, Kentucky W. Andrew Kofke , M.D., M.B.A., F.C.C.M. Hospital of the University of Pennsylvania Philadelphia, Pennsylvania 564 566 Abstract Object. Human albumin is used to induce hypervolemia (central venous pressure [CVP] > 8 mm Hg) after subarachnoid hemorrhage (SAH). Unfortunately, human albumin may increase the

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Lawrence C. Dempsey and Surl L. Nielsen

C urrent reexamination of cerebrospinal fluid dynamics in normal and hydrocephalic states has generated new interest in the ultrastructure of human ependyma. In this paper we depict for the first time the ciliated appearance of human lateral ventricles as delineated by scanning electron microscopy (SEM). Materials and Methods An 8-year-old boy with sepsis and pneumonitis suffered a respiratory arrest and died. Within 2 hours of death, multiple 2 × 2 mm sections were taken at autopsy from the lateral ventricular walls and immersed for 12 hours in 3

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Ulrich Batzdorf, Vivian Gold, Nancy Matthews and Josiah Brown

eosinophilic or mixed adenomas. In general, the clinical condition of acromegaly is correlated with the histological diagnosis of eosinophilic or mixed adenoma. The histological diagnosis of chromophobe adenoma, however, is not uncommon in patients with acromegaly. In a recent survey of 64 patients with pituitary tumors, 24 a histological diagnosis of chromophobe adenoma was made in five of 12 acromegalic patients whereas the remaining seven had eosinophilic or mixed tumors, as anticipated. The hypopituitary patients, without exception, had chromophobe adenomas. Human

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Ernst M. H. van den Doel, Gert Rijksen, Paul J. M. Roholl, Cees W. M. van Veelen and Gerard E. J. Staal

E nolase (2-phospho-D-glyceratehydrolase, EC 4.2.1.11) catalyzes the conversion of 2-phospho-D-glycerate to phosphoenolpyruvate in the glycolytic pathway. It is a dimeric enzyme of about 90,000-dalton molecular weight; three subunits have been recognized and designated α, β , and γ. 25, 36 Of the six possible combinations of two subunits, only αα, β β , α β , αγ, and γγ have been found in human tissues; β γ has not been demonstrated. In human tissues, the αα-isoenzyme is most frequently encountered; however, as β β is the predominant enzyme in muscle

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The first human stereotaxic apparatus

The contribution of Aubrey Mussen to the field of stereotaxis

Claude Picard, Andre Olivier and Gilles Bertrand

T he history of stereotaxic instruments began with Dittmar who, in 1873, used a guiding device for his instruments to produce circumscribed lesions of the bulbar vasomotor centers of the rat. 15 In 1889, Zernov, 17 Professor of Anatomy at Moscow University, built his own guiding apparatus, called an “encephalometer.” Although Zernov and his colleagues used this apparatus in human surgery, and it was later recognized by Kandel and Schavinsky 6 as an ancestor of modern stereotaxic apparatus, the “encephalometer” was employed mainly in surface topography for

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Edward R. Laws Jr. and John S. O'Connor

part of a section to another. These considerations and the limitations of histochemical techniques that use stains made it necessary to turn to quantitative techniques applied to small bits of carefully dissected and strictly controlled tissue. The total activity of ATPase, stimulated by optimal concentrations of sodium and potassium, has been quantitatively determined in 59 human brain tumors. Values for basic Mg ++ -ATPase and ouabain-inhibited ATPase were also determined in the majority of the tumors. Materials and Methods All pathological tissue was

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Mallory Peterson, Benjamin C. Warf and Steven J. Schiff

hydrocephalic brain volume growth curves in mice. 21 In that work, normative brain volume growth data from healthy mice were fit with a natural log least squares curve over time. This curve could then be compared with mice with induced hydrocephalus, and different growth patterns were identified. 21 We subsequently compiled normative brain volume growth data for humans using the NIH repository of normal pediatric brain MRI. 2 The resulting data were fit with a one-term power law based on the common use of the power law in the literature on biological allometric growth. The