A reproducible model of an epidural mass lesion in rodents. Part II: Characterization by in vivo magnetic resonance imaging

2002 ◽  
Vol 97 (6) ◽  
pp. 1419-1423 ◽  
Author(s):  
Martin Bendszus ◽  
Ralf Burger ◽  
Giles Hamilton Vince ◽  
Laszlo Solymosi
Keyword(s):  
Magnetic Resonance Imaging ◽  
White Matter ◽  
Magnetic Resonance ◽  
Parietal Lobe ◽  
Mass Lesion ◽  
Resonance Imaging ◽  
Content Type ◽  
Sustained Inflation ◽  
Fine Print

Object. The goal of this study was to characterize a novel epidural space-occupying lesion caused by balloon expansion in rodents by using sequential in vivo magnetic resonance (MR) imaging Methods. Ten Sprague—Dawley rats were intraperitoneally sedated. A trephination was performed over the left parietal cortex to attach a balloon-expansion device, which was secured with dental cement. Measurements were performed using a 1.5-tesla MR imaging device to obtain sequential T2-weighted and diffusion-weighted (DW) sequences in the coronal plane. A three-dimensional, constructed interference in steady state sequence was used for calculation of the balloon volume. The animal's temperature, heartbeat, and the arterial percentage of oxygen saturation were monitored continuously. After a baseline examination had been performed, the balloon was inflated for a 30-minute period until it reached a maximum volume of 0.3 ml; this procedure was followed by a period of sustained inflation lasting 30 minutes, balloon deflation, and a period of reperfusion lasting 3 hours. After perfusion fixation of the animals, morphometric analysis of the lesion size and examination of the percentage of viable neurons in the hippocampus were performed. Magnetic resonance imaging allowed for the precise visualization of the extension and location of the epidural mass lesion, narrowing of the basal cisterns, and development of a midline shift. A white-matter focus of hyperintensity, consistent with brain edema, developed predominantly in the contralateral temporal lobe. During sustained inflation the volume of the balloon did not change and comprised 5 to 7% of total intracranial volume. During the same period the white-matter edema progressed further but no increased signal was revealed on DW images. After balloon deflation the brain reexpanded to the calvaria and imaging signs of raised intracranial pressure subsided. A cortical area of hyperintensity on T2-weighted images developed in the parietal lobe in the region of the former balloon compression. This area appeared bright on DW images, a finding that corresponded to an early cytotoxic edema. After deflation white-matter vasogenic edema in the temporal lobes regressed within 3 hours after reperfusion. The cortical edema in the parietal lobe and the ipsilateral basal ganglia became sharply demarcated. The histopathological results (that is, the extent of tissue damage) corresponded with findings of the authors' companion investigation, which appears in this issue. Conclusions. Magnetic resonance imaging allows for a precise and sequential in vivo monitoring of a space-occupying epidural mass lesion and visualizes the time course of vasogenic and cytotoxic brain edema. This rodent model of an epidural mass lesion proved to be reproducible.

Altered diffusion and perfusion in hydrocephalic rat brain: a magnetic resonance imaging analysis

2000 ◽  
Vol 92 (3) ◽  
pp. 442-447 ◽  
Author(s):  
Eric M. Massicotte ◽  
Richard Buist ◽  
Marc R. Del Bigio
Keyword(s):  
Magnetic Resonance Imaging ◽  
White Matter ◽  
Magnetic Resonance ◽  
Rat Brain ◽  
Relaxation Times ◽  
Resonance Imaging ◽  
Waste Products ◽  
Content Type ◽  
Experimental Hydrocephalus ◽  
Fine Print

Object. It can be inferred from data published in the literature that brain compression occurs in the early stages of acute hydrocephalus and that drainage of extracellular waste products is impaired. The authors hypothesized that compression of the cortex would alter water distribution and retard the diffusion of fluid in the hydrocephalic brain.Methods. Proton diffusion, blood perfusion, and T1 and T2 relaxation times were determined in adult rat brain by using magnetic resonance imaging prior to, and 1 and 8 days after induction of hydrocephalus by kaolin injection. Five anatomical regions of interest were studied. The striatum, dorsal cortex, and lateral cortex exhibited decreased T2 and apparent diffusion coefficient (ADC) values but no change in perfusion. Examination of white matter revealed an initial decrease in ADC followed by a significant increase. The T2 relaxation times increased and perfusion decreased progressively between 1 and 8 days after induction of hydrocephalus.Conclusions. Acute experimental hydrocephalus causes compression of gray matter, perhaps associated with reduction in total water, which impairs diffusion of water in the tissue. White matter compression and hypoperfusion precede the development of edema. These findings have importance for understanding the neurochemical changes that occur in hydrocephalic brains.

A new reproducible model of an epidural mass lesion in rodents. Part I: Characterization by neurophysiological monitoring, magnetic resonance imaging, and histopathological analysis

2002 ◽  
Vol 97 (6) ◽  
pp. 1410-1418 ◽  
Author(s):  
Ralf Burger ◽  
Martin Bendszus ◽  
Giles Hamilton Vince ◽  
Klaus Roosen ◽  
Anthony Marmarou
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Mr Imaging ◽  
Mass Lesion ◽  
Neurophysiological Monitoring ◽  
Histopathological Analysis ◽  
Resonance Imaging ◽  
Eeg Activity ◽  
Content Type ◽  
Fine Print

Object. The goal of this study was to characterize a new model of an epidural mass lesion in rodents by means of neurophysiological monitoring, magnetic resonance imaging, and histopathological analysis. Methods. Changes in intracranial pressure (ICP), cerebral perfusion pressure (CPP), and laser Doppler flowmetry (LDF) values, intraparenchymal tissue partial oxygen pressure (PtiO2), and electroencephalography (EEG) activity were evaluated in the rat during controlled, epidural expansion of a latex balloon up to a maximum ICP of 60 mm Hg. The initial balloon inflation was followed by periods of sustained inflation (30 ± 1 minute) and reperfusion (180 ± 5 minutes). Histopathological analysis and magnetic resonance (MR) imaging were performed to characterize the lesion. The time to maximum balloon expansion and the average balloon volume were highly reproducible. Alterations in EEG activity during inflation first appeared when the CPP decreased to 57 mm Hg, the LDF value to 66% of baseline values, and the PtiO2 to 12 mm Hg. During maximum compression, the CPP was reduced to 34 mm Hg, the LDF value to 40% of baseline, and the PtiO2 to 4 to 5 mm Hg. The EEG tracing was isoelectric during prolonged inflation and the values of LDF and PtiO2 decreased due to accompanying hypotonia. After reperfusion, the CPP was significantly decreased (p < 0.05) due to the elevation of ICP. Both the LDF value and EEG activity displayed incomplete restoration, whereas the value of PtiO2 returned to normal. Histological analysis and MR imaging revealed brain swelling with a midline shift and a combined cortical—subcortical ischemic lesion beyond the site of balloon compression. Conclusions. This novel model of an epidural mass lesion in rodents closely resembles the process observed in humans. Evaluation of pathophysiological and morphological changes was feasible by using neurophysiological monitoring and MR imaging.

Optic pathway glioma infiltrating into somatostatinergic pathways in a young boy with gigantism

1994 ◽  
Vol 81 (4) ◽  
pp. 595-600 ◽  
Author(s):  
Thomas J. Manski ◽  
Charles S. Ha worth ◽  
Bertrand J. Duval-Arnould ◽  
Elisabeth J. Rushing
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Optic Pathway Glioma ◽  
Optic Pathway ◽  
Resonance Imaging ◽  
Content Type ◽  
Hyperintense Signal ◽  
Immunocytochemical Studies ◽  
Stereotactic Biopsies ◽  
Fine Print

✓ The authors report gigantism in a 16-month-old boy with an extensive optic pathway glioma infiltrating into somatostatinergic pathways, as revealed by magnetic resonance imaging and immunocytochemical studies. Stereotactic biopsies of areas showing hyperintense signal abnormalities on T2-weighted images in and adjacent to the involved visual pathways provided rarely obtained histological correlation of such areas. The patient received chemotherapy, which resulted in reduction of size and signal intensity of the tumor and stabilization of vision and growth velocity.

Magnetic resonance imaging of spinal arteriovenous malformations

1987 ◽  
Vol 66 (6) ◽  
pp. 830-834 ◽  
Author(s):  
John L. Doppman ◽  
Giovanni Di Chiro ◽  
Andrew J. Dwyer ◽  
Joseph L. Frank ◽  
Edward H. Oldfield
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Arteriovenous Malformations ◽  
High Signal ◽  
Resonance Imaging ◽  
Content Type ◽  
Spinal Arteriovenous Malformations ◽  
Magnetic Resonance Imaging Mri ◽  
Spinal Avm ◽  
Fine Print

✓ Magnetic resonance imaging (MRI) was performed on 12 patients with spinal arteriovenous malformations (AVM's). Six lesions were intramedullary, five were dural, and one was in a posterior extramedullary location. Serpentine filling defects similar to the classic myelographic findings were demonstrated within the high-signal cerebrospinal fluid on T2-weighted coronal scans. The intramedullary nidus was identified by MRI as an area of low-signal intensity within the cord in all six intramedullary AVM's. Neither the dural nor the posterior extramedullary lesions showed intramedullary components. It is concluded that MRI may noninvasively provide the initial diagnosis of a spinal AVM and distinguish intramedullary from dural and extramedullary lesions.

Optic nerve ganglioglioma

1993 ◽  
Vol 78 (6) ◽  
pp. 979-982 ◽  
Author(s):  
William Y. Lu ◽  
Marc Goldman ◽  
Byron Young ◽  
Daron G. Davis
Keyword(s):  
Magnetic Resonance Imaging ◽  
Nervous System ◽  
Optic Nerve ◽  
Magnetic Resonance ◽  
Visual Field ◽  
Resonance Imaging ◽  
Optic Nerve Glioma ◽  
Content Type ◽  
Visual Field Deficit ◽  
Fine Print

✓ Gangliogliomas of the optic nerve are extremely rare. The case is reported of a 38-year-old man who presented with a visual field deficit and was discovered to have an optic nerve ganglioglioma. The possible embryological origins of this neoplasm, its histological and immunohistochemical features, and its appearance on magnetic resonance imaging are examined. The prognoses of optic nerve glioma and of gangliogliomas occurring elsewhere in the nervous system are compared.

Correlation of the relationships of brain—tumor interfaces, magnetic resonance imaging, and angiographic findings to predict cleavage of meningiomas

1999 ◽  
Vol 91 (3) ◽  
pp. 384-390 ◽  
Author(s):  
Faruk İldan ◽  
Metin Tuna ◽  
Alp İskender Göcer ◽  
Bülent Boyar ◽  
Hüseyin Bağdatoğlu ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Brain Tumor ◽  
Magnetic Resonance ◽  
Mr Imaging ◽  
Vascular Supply ◽  
Peritumoral Edema ◽  
Resonance Imaging ◽  
Content Type ◽  
Angiographic Findings ◽  
Fine Print

Object. The authors examined the relationships of brain—tumor interfaces, specific magnetic resonance (MR) imaging features, and angiographic findings in meningiomas to predict tumor cleavage and difficulty of resection.Methods. Magnetic resonance imaging studies, angiographic data, operative reports, clinical data, and histopathological findings were examined retrospectively in this series, which included 126 patients with intracranial meningiomas who underwent operations in which microsurgical techniques were used. The authors have identified three kinds of brain—tumor interfaces characterized by various difficulties in microsurgical dissection: smooth type, intermediate type, and invasive type. The signal intensity on T1-weighted MR images was very similar regardless of the type of brain—tumor interface (p > 0.1). However, on T2-weighted images the different interfaces seemed to correlate very precisely with the signal intensity and the amount of peritumoral edema (p < 0.01), allowing the prediction of microsurgical effort required during surgery. On angiographic studies, the pial—cortical arterial supply was seen to participate almost equally with the meningeal—dural arterial supply in vascularizing the tumor in 57.9% of patients. Meningiomas demonstrating hypervascularization on angiography, particularly those fed by the pial—cortical arteries, exhibited significantly more severe edema compared with those supplied only from meningeal arteries (p < 0.01). Indeed, a positive correlation was found between the vascular supply from pial—cortical arteries and the type of cleavage (p < 0.05).Conclusions. In this analysis the authors proved that there is a strong correlation between the amount of peritumoral edema, hyperintensity of the tumor on T2-weighted images, cortical penetration, vascular supply from pial—cortical arteries, and cleavage of the meningioma. Therefore, the consequent difficulty of microsurgical dissection can be predicted preoperatively by analyzing MR imaging and angiographic studies.

Intracranial chondroma in a patient with Ollier's disease

1989 ◽  
Vol 70 (2) ◽  
pp. 274-276 ◽  
Author(s):  
Robert F. Traflet ◽  
Ashok R. Babaria ◽  
Giancarlo Barolat ◽  
H. T. Doan ◽  
Carlos Gonzalez ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Computerized Tomography ◽  
Diagnostic Value ◽  
Resonance Imaging ◽  
Content Type ◽  
Ollier’S Disease ◽  
Intracranial Chondroma ◽  
Ollier's Disease ◽  
Fine Print

✓ A case is presented in which a solitary chondroma arose from the clivus of a patient with Ollier's disease. These tumors are rare. The diagnostic value of computerized tomography and magnetic resonance imaging is discussed.

Spinal intramedullary tuberculous lesion: medical management

2000 ◽  
Vol 93 (1) ◽  
pp. 137-141 ◽  
Author(s):  
G. Prakash Rao
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Medical Management ◽  
Treatment Protocol ◽  
Resonance Imaging ◽  
Content Type ◽  
Tuberculous Lesion ◽  
Fine Print

✓ The author describes the successful medical management of intramedullary tuberculous lesions in four patients who received treatment between 1994 and 1997. The role of magnetic resonance imaging and the treatment protocol for intramedullary tuberculous lesions are also discussed.

Wegener granulomatosis manifesting as meningitis

2002 ◽  
Vol 97 (5) ◽  
pp. 1229-1232 ◽  
Author(s):  
Takao Yasuhara ◽  
Toru Fukuhara ◽  
Minoru Nakagawa ◽  
Yoshinori Terai ◽  
Kimihiro Yoshino ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Immunosuppressive Therapy ◽  
Antineutrophil Cytoplasmic Antibody ◽  
Resonance Imaging ◽  
Pia Mater ◽  
Meningeal Enhancement ◽  
Wegener Granulomatosis ◽  
Content Type ◽  
Fine Print

✓ The authors describe a unique presentation of Wegener granulomatosis (WG) manifesting predominantly as meningitis. Magnetic resonance imaging demonstrated diffuse meningeal enhancement, including the pia mater, in a 28-yearold man with meningitis. A diagnosis of atypical WG was based on the findings of a dural biopsy sample and an elevated cytoplasmic antineutrophil cytoplasmic antibody (cANCA) titer, although the patient did not have any of the lesions common to WG. Immunosuppressive therapy was quite effective. With treatment, the meningeal enhancement resolved and the cANCA titer normalized. Meningeal granulomatosis as the sole lesion in WG has never been reported in the literature. This atypical course of WG should be noted.

Sign in / Sign up

Export Citation Format

Share Document