The effect of craniectomy on the biomechanics of normal brain

1987 ◽  
Vol 67 (4) ◽  
pp. 573-578 ◽  
Author(s):  
Shizuo Hatashita ◽  
Julian T. Hoff
Keyword(s):  
White Matter ◽  
Brain Tissue ◽  
Volume Index ◽  
Normal Brain ◽  
Tissue Pressure ◽  
Content Type ◽  
Cerebrovascular Resistance ◽  
Tissue Resistance ◽  
Tissue Compliance ◽  
Fine Print

✓ Does an open skull alter the fundamental biomechanical properties of normal brain tissue? This question was studied in 32 anesthetized cats, 16 of which underwent a standard craniectomy (2.5 × 2.0 cm) in the left frontoparietal region. Brain tissue pressure, regional cerebral blood flow (rCBF), and brain water content were measured from the same area of cortical gray and white matter, and intracranial pressure (ICP) was recorded from the cisterna magna. Brain tissue resistance, tissue compliance, and the pressure-volume index were analyzed in response to a bolus injection of saline into brain tissue or the cisterna magna. Cerebrovascular resistance was also calculated. In craniectomized animals 2 hours after surgery, ICP had fallen to 3.75 ± 0.39 mm Hg, and cortical gray and white matter tissue pressure had fallen to 3.19 ± 0.47 and 4.69 ± 0.54 mm Hg, respectively (mean ± standard error of the mean); these variables did not fall further over 4 hours. The pressure-volume index in the same animals increased significantly from 0.67 ± 0.01 to 0.86 ± 0.04 ml. Tissue compliance rose in the cortical gray matter but tissue resistance fell, approximating that found in subjacent white matter. There was no significant difference between animals with and without craniectomy in rCBF, cerebrovascular resistance, or brain water content in either gray or white matter. These findings indicate that in the cat craniectomy causes an increase in the compensatory capacity of the intracranial cavity to increased volume. The data also indicate that cortical tissue has high hydraulic conductivity and compliance when the skull is opened.

Dynamic determination of human glioma invasion in vitro

1998 ◽  
Vol 89 (3) ◽  
pp. 441-447 ◽  
Author(s):  
Svein J. T. Nygaard ◽  
Hans K. R. Haugland ◽  
Ole Didrik Laerum ◽  
Morten Lund-Johansen ◽  
Rolf Bjerkvig ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Tumor Cell ◽  
Brain Tissue ◽  
Normal Brain ◽  
Tumor Spheroids ◽  
Normal Brain Tissue ◽  
Content Type ◽  
Biopsy Specimens ◽  
Fine Print

Object. The goal of this study was to evaluate whether there is any relationship between survival of patients with brain tumor and tumor proliferation or tumor invasion in vitro. Methods. Samples of freshly resected brain tumors from 14 patients with glioblastoma multiforme (GBM) were directly grown as three-dimensional multicellular spheroids. The tumor spheroids were cocultured with fetal rat brain cell aggregates (BCAs), used to represent an organotypical normal brain tissue model. Before the coculture, the tumor spheroids and the BCAs were stained with two different carbocyanine dyes, 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate (DiI) and 3,3′-dioctadecycloxacarbocyanine perchlorate (DiO), respectively. During the coculture, confocal laser scanning microscopy allowed a sequential analysis of tumor cell invasion by visualizing dynamic aspects of the invasive process. Single cocultures were examined at three different time points (24, 48, and 96 hours). During the observation period there was a change in the structural morphology of the cocultures, with a progressive decrease in BCA volume. Furthermore, the scanning confocal micrographs revealed a bidirectional movement of tumor cells and normal cells into brain and tumor tissue, respectively. It is also shown that there is a considerable variation in the rate of BCA destruction in cocultures of glioma spheroids generated directly from biopsy specimens. This variation is seen both between spheroids generated from the same biopsy as well as between spheroids that are grown from different biopsy specimens. Cell proliferation measured by Ki-67 immunohistochemical analysis of biopsy samples obtained in the same patients revealed a correlation between tumor cell proliferation and tissue destruction of the BCAs, as determined by a reduction in BCA volume (p = 0.0338). No correlation was found when survival was related to the same parameters (p > 0.05). Conclusions. The present work provides a model for quick and efficient assessment of dynamic interactions between tumor and normal brain tissue shortly after surgery.

The intracerebral distribution of BCNU delivered by surgically implanted biodegradable polymers

1992 ◽  
Vol 76 (4) ◽  
pp. 640-647 ◽  
Author(s):  
Stuart A. Grossman ◽  
Carla Reinhard ◽  
O. Michael Colvin ◽  
Mark Chasin ◽  
Robert Brundrett ◽  
...  
Keyword(s):  
New Zealand ◽  
Brain Tissue ◽  
Direct Injection ◽  
Normal Brain ◽  
Local Concentration ◽  
Content Type ◽  
Drug Concentrations ◽  
New Zealand White Rabbits ◽  
The Brain ◽  
Fine Print

✓ The local concentration and distribution of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) within normal brain tissue were studied following surgical implantation of biodegradable polymer containing BCNU in New Zealand White rabbits. Cylindrical discs of poly(bis(p-carboxyphenoxy)-propane:sebacic acid) copolymer in a 20:80 formulation were made containing [3H]-inulin or [3H]-BCNU labeled in the methylene hydrogens of the chloroethyl groups. These were implanted in the brains of 56 New Zealand White rabbits. The animals were sacrificed 3, 7, 14, or 21 days later and the brains were rapidly removed, frozen, and prepared for quantitative autoradiography. Autoradiographs from coronal sections bisecting the polymer were analyzed to determine both the proportion of the brain section exposed to the tracer and the local drug concentrations as a function of distance from the polymer. Tritiated BCNU was also injected directly into the brains of eight additional rabbits, and local brain concentrations were studied over time. The results of this study demonstrate that approximately 50% of the area of the brain sections was exposed to radiolabeled compound 3 days after BCNU-polymer implantation, 15% at 7 days, and less than 10% at 14 and 21 days. Polymer discs containing 600 µg BCNU generated 6 mM concentrations of BCNU in brain tissue 10 mm from the polymer at 3 and 7 days. Pharmacological studies demonstrated that approximately 25% of the tritium label was associated with intact BCNU 3 days following polymer implantation. Radiolabeled inulin delivered by polymer remained dispersed throughout the ipsilateral hemisphere for 14 days. Direct injection of [3H]-BCNU into brain parenchyma resulted in widely distributed tracer at 1 and 3 hours with rapid disappearance thereafter. It is concluded that local delivery of BCNU to brain tissue with this polymeric drug delivery system results in sustained high local concentrations of BCNU which may be of value in the treatment of patients with brain tumors.

A comparative study on the pharmacokinetics and biodistribution of boronated porphyrin (BOPP) and sulfhydryl boron hydride (BSH) in the RG2 rat glioma model

1995 ◽  
Vol 83 (1) ◽  
pp. 86-92 ◽  
Author(s):  
Crister P. Ceberg ◽  
Arne Brun ◽  
Stephen B. Kahl ◽  
Myoung Seo Koo ◽  
Bertil R. R. Persson ◽  
...  
Keyword(s):  
Body Weight ◽  
Tumor Cells ◽  
Brain Tissue ◽  
Malignant Gliomas ◽  
Normal Brain ◽  
Boron Hydride ◽  
Content Type ◽  
Rat Glioma ◽  
Glioma Model ◽  
Fine Print

✓ Boron neutron capture therapy is a treatment modality for cancer that depends on the specific uptake of boron by the tumor cells. The infiltrative growth of malignant gliomas requires that boron reach and accumulate in migrating cells outside the margin of the tumor; thus, it is important that the biodistribution of new boron compounds is also studied in the surrounding healthy brain tissue. This study is undertaken in the present work, in which the biodistribution and pharmacokinetics of sulfhydryl boron hydride (BSH) and boronated porphyrin (BOPP) in the RG2 rat glioma model are investigated. This model mimics the characteristics of human glioma with cells migrating into the surrounding brain. The animals were infused intravenously with either BSH (25 µg or 175 µg of boron per gram of body weight) or BOPP (12 µg of boron per gram body weight). For the low dose of BSH, the maximum tumor—boron content was 8 ppm at approximately 9 hours after the infusion with a tumor-to-blood ratio of 0.6. At the higher dose, the corresponding figures were 15 ppm after 12 hours with a tumor-to-blood ratio of 0.5. For BOPP, a tumor—boron concentration of 81 ppm was achieved 24 hours after the infusion and sustained in that range for at least 72 hours. The tumor-to-blood ratio at 24 hours was slightly above 6, but continued to increase as the blood was cleared. These results indicate that both compounds are spread into the normal brain tissue following the same pathways as the migrating tumor cells and in this way can be taken up even in distant tumor cell foci.

Observations of intracranial neoplasms treated with gamma knife radiosurgery

2002 ◽  
Vol 97 ◽  
pp. 623-626 ◽  
Author(s):  
György T. Szeifert ◽  
Nicolas Massager ◽  
Daniel DeVriendt ◽  
Philippe David ◽  
Françoise De Smedt ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Brain Tissue ◽  
Gamma Knife ◽  
Tumor Tissue ◽  
Gamma Knife Radiosurgery ◽  
Normal Brain ◽  
Vascular Endothelial ◽  
Normal Brain Tissue ◽  
Content Type ◽  
Fine Print

Object. The purpose of this study was to compare histopathological changes with imaging findings in different tumors after gamma knife radiosurgery (GKS). Methods. Five patients of a series of 220 treated with GKS underwent craniotomy for tumor removal 3 to 12 months after radiosurgery. There were two patients with multiple cerebral metastases, one with vestibular schwannoma, one with malignant glioma, and one with meningioma. A portion of normal brain tissue outside the prescription dose volume was acquired wherever possible to facilitate examination of the effects of radiosurgery. Histopathological and immunohistochemical investigations were performed. In addition to the routine hematoxylin and eosin and Mallory trichrome stains, immunohistochemical reactions were also performed for Factor VIII—associated antigen (FVIII) and CD34 antigen to study vascular endothelial effects of the irradiation. Endothelial cells of vessels in the normal brain tissue covering the tumor, outside of the prescription isodose volume, expressed marked CD34 and FVIII positivity. In the irradiated targeted tumor tissue samples, however, both reactions decreased remarkably. Conclusions. The results of the present immunohistochemical study provide support to the experimental hypothesis that vascular endothelial cells are the principal targets of single high-dose irradiation. The loss of central contrast enhancement of tumor tissue following radiosurgery might be consequence of the vascular damage.

Regional brain tissue pressure gradients created by expanding extradural temporal mass lesion

1997 ◽  
Vol 86 (3) ◽  
pp. 505-510 ◽  
Author(s):  
Christopher E. Wolfla ◽  
Thomas G. Luerssen ◽  
Robin M. Bowman
Keyword(s):  
Intracranial Pressure ◽  
Frontal Lobe ◽  
Brain Tissue ◽  
Temporal Lobe ◽  
Mass Lesion ◽  
Pressure Monitor ◽  
Tissue Pressure ◽  
Content Type ◽  
Regional Brain ◽  
The Right

✓ A porcine model of regional intracranial pressure was used to compare regional brain tissue pressure (RBTP) changes during expansion of an extradural temporal mass lesion. Measurements of RBTP were obtained by placing fiberoptic intraparenchymal pressure monitors in the right and left frontal lobes (RF and LF), right and left temporal lobes (RT and LT), midbrain (MB), and cerebellum (CB). During expansion of the right temporal mass, significant RBTP gradients developed in a reproducible pattern: RT > LF = LT > RF > MB > CB. These gradients appeared early, widened as the volume of the mass increased, and persisted for the entire duration of the experiment. The study indicates that RBTP gradients develop in the presence of an extradural temporal mass lesion. The highest RBTP was recorded in the ipsilateral temporal lobe, whereas the next highest was recorded in the contralateral frontal lobe. The RBTP that was measured in either frontal lobe underestimated the temporal RBTP. These results indicated that if a frontal intraparenchymal pressure monitor is used in a patient with temporal lobe pathology, the monitor should be placed on the contralateral side and a lower threshold for therapy of increased intracranial pressure should be adopted. Furthermore, this study provides further evidence that reliance on a single frontal intraparenchymal pressure monitor may not detect all areas of elevated RBTP.

Use of an intracranial near-infrared probe for localization during stereotactic surgery for movement disorders

2000 ◽  
Vol 93 (3) ◽  
pp. 498-505 ◽  
Author(s):  
Cole A. Giller ◽  
Maureen Johns ◽  
Hanli Liu
Keyword(s):  
White Matter ◽  
Gray Matter ◽  
Movement Disorders ◽  
Near Infrared ◽  
Subcortical White Matter ◽  
Stereotactic Surgery ◽  
Resected Specimen ◽  
Subcortical Structures ◽  
Content Type ◽  
Fine Print

✓ Localization of targets during stereotactic surgery is frequently accomplished by identification of the boundaries between the gray matter of various nuclei and the surrounding white matter. The authors describe an intracranial probe developed for this purpose, which uses near-infrared (NIR) light.The probe fits through standard stereotactic holders and emits light at its tip. The scattered light is detected and analyzed by a spectrometer, with the slope of the trailing portion of the reflectance curve used as the measurement value.Near-infrared readings were obtained during 27 neurosurgical procedures. The first three operations were temporal lobectomies, with values obtained from tracks in the resected specimen and resection bed. In the next five procedures, the probe was inserted stereotactically to a depth of 1 to 2 cm with measurements obtained every 1 mm. The probe was then used in 19 stereotactic procedures for movement disorders, obtaining measurements every 0.5 to 1 mm to target depths of 6 to 8 cm to interrogate subcortical structures. The NIR signals were correlated to distances beneath the cortical surface measured on postoperative computerized tomography or magnetic resonance imaging by using angle correction and three-dimensional reconstruction techniques.The NIR values for white and gray matter obtained during the lobectomies were significantly different (white matter 2.5 ± 0.37, gray matter 0.82 ± 0.23 mean ± standard deviation). The NIR values from the superficial stereotactic tracks showed initial low values corresponding to cortical gray matter and high values corresponding to subcortical white matter.There was good correlation between the NIR signals and postoperative imaging in the 19 stereotactic cases. Dips due to adjacent sulci, a plateau of high signal due to subcortical white matter, a dip in the NIR signal during passage through the ventricle, dips due to the caudate nucleus, and peaks due to the white matter capsule between ventricle and thalamus were constant features. The putamen—capsule boundary and the lamina externa and interna of the globus pallidus could be distinguished in three cases. Elevated signals corresponding to the thalamic floor were seen in 10 cases. Nuances such as prior lesions and nonspecific white matter changes were also detected. There was no incidence of morbidity associated with use of the probe. Data acquisition was straightforward and the equipment required for the studies was inexpensive.The NIR probe described in this article seems to be able to detect gray—white matter boundaries around and within subcortical structures commonly encountered in stereotactic functional neurosurgery. This simple, inexpensive method deserves further study to establish its efficacy for stereotactic localization.

Intracranial volume-pressure relationship in man

1982 ◽  
Vol 56 (4) ◽  
pp. 524-528 ◽  
Author(s):  
Joseph Th. J. Tans ◽  
Dick C. J. Poortvliet
Keyword(s):  
Best Approximation ◽  
Continuous Monitoring ◽  
Fluid Pressure ◽  
Constant Term ◽  
Volume Index ◽  
Intracranial Volume ◽  
Content Type ◽  
The Best Approximation ◽  
Ventricular Fluid Pressure ◽  
Fine Print

✓ The pressure-volume index (PVI) was determined in 40 patients who underwent continuous monitoring of ventricular fluid pressure. The PVI value was calculated using different mathematical models. From the differences between these values, it is concluded that a monoexponential relationship with a constant term provides the best approximation of the PVI.

The deposition of Hg203-chlormerodrin in experimental brain tumors

1971 ◽  
Vol 35 (3) ◽  
pp. 303-308 ◽  
Author(s):  
Tatsuya Kobayashi ◽  
Louis Bakay ◽  
Joseph C. Lee
Keyword(s):  
Brain Tumors ◽  
Tumor Cells ◽  
Normal Brain ◽  
Intracranial Tumors ◽  
Electron Microscopic ◽  
Electron Microscopic Autoradiography ◽  
Content Type ◽  
Meningeal Tumors ◽  
Vacuolar System ◽  
Fine Print

✓ The deposition of Hg203-chlormerodrin was studied in intracranial tumors in mice induced by implantation of 20-methyl cholanthrene by tissue assay, as well as light microscopic and electron microscopic autoradiography. The investigations were carried out in astrocytomas, glioblastomas, and meningeal tumors. The chlormerodrin content of the tumors exceeded that of normal brain with a significant tumor/brain ratio ranging from 5.8 to 22.5. It was found that the chlormerodrin molecule becomes rapidly incorporated in the tumor cells, with a preference for that portion of the cytoplasm associated with the vacuolar system.

Early metabolic alterations in edematous perihematomal brain regions following experimental intracerebral hemorrhage

1998 ◽  
Vol 88 (6) ◽  
pp. 1058-1065 ◽  
Author(s):  
Kenneth R. Wagner ◽  
Guohua Xi ◽  
Ya Hua ◽  
Marla Kleinholz ◽  
Gabrielle M. de Courten-Myers ◽  
...  
Keyword(s):  
White Matter ◽  
Intracerebral Hemorrhage ◽  
Gray Matter ◽  
High Energy ◽  
Brain Regions ◽  
Large Animal ◽  
High Energy Phosphate ◽  
Content Type ◽  
Water Contents ◽  
Fine Print

Object. The authors previously demonstrated, in a large-animal intracerebral hemorrhage (ICH) model, that markedly edematous (“translucent”) white matter regions (> 10% increases in water contents) containing high levels of clotderived plasma proteins rapidly develop adjacent to hematomas. The goal of the present study was to determine the concentrations of high-energy phosphate, carbohydrate substrate, and lactate in these and other perihematomal white and gray matter regions during the early hours following experimental ICH. Methods. The authors infused autologous blood (1.7 ml) into frontal lobe white matter in a physiologically controlled model in pigs (weighing approximately 7 kg each) and froze their brains in situ at 1, 3, 5, or 8 hours postinfusion. Adenosine triphosphate (ATP), phosphocreatine (PCr), glycogen, glucose, lactate, and water contents were then measured in white and gray matter located ipsi- and contralateral to the hematomas, and metabolite concentrations in edematous brain regions were corrected for dilution. In markedly edematous white matter, glycogen and glucose concentrations increased two- to fivefold compared with control during 8 hours postinfusion. Similarly, PCr levels increased several-fold by 5 hours, whereas, except for a moderate decrease at 1 hour, ATP remained unchanged. Lactate was markedly increased (approximately 20 µmol/g) at all times. In gyral gray matter overlying the hematoma, water contents and glycogen levels were significantly increased at 5 and 8 hours, whereas lactate levels were increased two- to fourfold at all times. Conclusions. These results, which demonstrate normal to increased high-energy phosphate and carbohydrate substrate concentrations in edematous perihematomal regions during the early hours following ICH, are qualitatively similar to findings in other brain injury models in which a reduction in metabolic rate develops. Because an energy deficit is not present, lactate accumulation in edematous white matter is not caused by stimulated anaerobic glycolysis. Instead, because glutamate concentrations in the blood entering the brain's extracellular space during ICH are several-fold higher than normal levels, the authors speculate, on the basis of work reported by Pellerin and Magistretti, that glutamate uptake by astrocytes leads to enhanced aerobic glycolysis and lactate is generated at a rate that exceeds utilization.

Subtle deterioration in shunted childhood hydrocephalus

1986 ◽  
Vol 65 (2) ◽  
pp. 211-216 ◽  
Author(s):  
Arno Fried ◽  
Kenneth Shapiro
Keyword(s):  
Buffering Capacity ◽  
Volume Index ◽  
Shunt Revision ◽  
Pressure Waves ◽  
Ventricular Size ◽  
Csf Shunts ◽  
Content Type ◽  
The Mean ◽  
Childhood Hydrocephalus ◽  
Fine Print

✓ Eighteen hydrocephalic children who presented with subtle deterioration when their shunts malfunctioned were studied during shunt revision by means of the pressure-volume index (PVI) technique. Bolus manipulation of cerebrospinal fluid (CSF) was used to determine the PVI and the resistance to the absorption of CSF (Ro). Ventricular size was moderately to severely enlarged in all the children. Steady-state intracranial pressure (ICP) at the time of shunt revision was 17.5 ± 7.3 mm Hg (range 8 to 35 mm Hg). Pressure waves could not be induced by bolus injections in the 8- to 35-mm Hg range of ICP tested. The mean ± standard deviation (SD) of the predicted normal PVI for this group was 18.5 ± 2.7 ml. The mean ± standard error of the mean of the measured PVI was 35.5 ± 2.1 ml, which represented a 187% ± 33% (± SD) increase in volume-buffering capacity (p < 0.001). The ICP did not fall after bolus injections in three children, so that the Ro could not be measured. In the remaining 15 patients, Ro increased linearly as a function of ICP (r = 0.74, p < 0.001). At ICP's below 20 mm Hg, Ro ranged from 2.0 to 5.0 mm Hg/ml/min, but increased to as high as 21 mm Hg/ml/min when ICP was above 20 mm Hg. This study documents that subtle deterioration in shunted hydrocephalic children is accompanied by abnormally compliant pressure-volume curves. These children develop ventricular enlargement and neurological deterioration without acute episodic pressure waves. The biomechanical profile of this group differs from other children with CSF shunts.

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