Cerebral arteriovenous malformations, steal, and the hypertensive breakthrough threshold

1987 ◽  
Vol 66 (4) ◽  
pp. 563-567 ◽  
Author(s):  
Michael K. Morgan ◽  
Ian Johnston ◽  
Michael Besser ◽  
David Baines

✓ An experiment was designed to investigate the effects of arteriovenous (AV) fistula occlusion on cerebral autoregulation. A right carotid-jugular fistula was created in 63 rats in such a way as to produce an intracranial AV fistula with a loop extension into the neck. The fistula was occluded after an 8-week interval with the rats under both normotension and metaraminol-induced hypertension, and evidence of blood-brain barrier disruption was investigated with an Evans blue dye technique. The results indicate that an intracranial AV fistula may cause cerebral steal which is responsible for a reduction in the threshold for hypertensive breakthrough following fistula occlusion.

1974 ◽  
Vol 40 (3) ◽  
pp. 313-321 ◽  
Author(s):  
John A. Kusske ◽  
William A. Kelly

✓ The authors report their experience with embolization of unresectable cerebral arteriovenous malformations in 10 patients; seven showed clinical improvement, two no change, and one became worse. Follow-up studies for up to 9 years suggest that partial obliteration of a lesion that shunts blood away from normal brain alleviates the clinical syndrome by enhancing cerebral perfusion. Thus, satisfactory results may be obtained without occlusion of malformations causing symptomatology on the basis of a cerebral steal.


2003 ◽  
Vol 99 (1) ◽  
pp. 65-70 ◽  
Author(s):  
Sònia Abilleira ◽  
Joan Montaner ◽  
Carlos A. Molina ◽  
Jasone Monasterio ◽  
José Castillo ◽  
...  

Object. Matrix metalloproteinases (MMPs) are overexpressed in the presence of some neurological diseases in which blood—brain barrier disruption exists. The authors investigated the MMP-9 concentration in patients after acute intracerebral hemorrhage (ICH) and its relation to perihematomal edema (PHE). Methods. Concentrations of MMP-9 and related proteins were determined in plasma by performing an enzyme-linked immunosorbent assay of samples drawn after hospital admission (< 24 hours after stroke) from 57 patients with ICH. The diagnosis of ICH was made on the basis of findings on computerized tomography (CT) scans. The volumes of ICH and PHE were measured on baseline and follow-up CT scans at the same time that the patient's neurological status was assessed using the Canadian Stroke Scale and the Glasgow Coma Scale. Increased expression of MMP-9 was found among patients with ICH. In cases of deep ICH, MMP-9 was significantly associated with PHE volume (r = 0.53; p = 0.01) and neurological worsening (237.4 compared with 111.3 ng/ml MMP-9; p = 0.04). A logistic regression model focusing on the study of absolute PHE volume showed ICH volume as an independent predictor (odds ratio [OR] 3.37; 95% confidence interval [CI] 1.1–10.3; p = 0.03). A second analysis of relative PHE volume (absolute PHE volume/ICH volume) in patients with deep ICH demonstrated that the only factor related to it was MMP-9 concentration (OR 11.6; 95% CI 1.5–89.1; p = 0.018). Conclusions. Expression of MMP-9 is raised after acute spontaneous ICH. Among patients with deep ICH this increase is associated with PHE and the development of neurological worsening within the acute stage.


1996 ◽  
Vol 85 (6) ◽  
pp. 1056-1065 ◽  
Author(s):  
Bernhard Zünkeler ◽  
Richard E. Carson ◽  
Jeff Olson ◽  
Ronald G. Blasberg ◽  
Hetty Devroom ◽  
...  

✓ Hyperosmolar blood-brain barrier disruption (HBBBD), produced by infusion of mannitol into the cerebral arteries, has been used in the treatment of brain tumors to increase drug delivery to tumor and adjacent brain. However, the efficacy of HBBBD in brain tumor therapy has been controversial. The goal of this study was to measure changes in vascular permeability after HBBBD in patients with malignant brain tumors. The permeability (K1) of tumor and normal brain blood vessels was measured using rubidium-82 and positron emission tomography before and repeatedly at 8- to 15-minute intervals after HBBBD. Eighteen studies were performed in 13 patients, eight with glioblastoma multiforme and five with anaplastic astrocytoma. The HBBBD increased K1 in all patients. Baseline K1 values were 2.1 ± 1.4 and 34.1 ± 22.1 µl/minute/ml (± standard deviation) for brain and tumor, respectively. The peak absolute increases in K1 following HBBBD were 20.8 ± 11.7 and 19.7 ± 10.7 µl/minute/ml for brain and tumor, corresponding to percentage increases of approximately 1000% in brain and approximately 60% in tumor. The halftimes for return of K1 to near baseline for brain and tumor were 8.1 ± 3.8 and 4.2 ± 1.2 minutes, respectively. Simulations of the effects of HBBBD made using a very simple model with intraarterial methotrexate, which is exemplary of drugs with low permeability, indicate that 1) total exposure of the brain and tumor to methotrexate, as measured by the methotrexate concentration-time integral (or area under the curve), would increase with decreasing infusion duration and would be enhanced by 130% to 200% and by 7% to 16%, respectively, compared to intraarterial infusion of methotrexate alone; and 2) exposure time at concentrations above 1 µM, the minimal concentration required for the effects of methotrexate, would not be enhanced in tumor and would be enhanced by only 10% in brain. Hyperosmolar blood-brain barrier disruption transiently increases delivery of water-soluble compounds to normal brain and brain tumors. Most of the enhancement of exposure results from trapping the drug within the blood-brain barrier, an effect of the very transient alteration of the blood-brain barrier by HBBBD. Delivery is most effective when a drug is administered within 5 to 10 minutes after disruption. However, the increased exposure and exposure time that occur with methotrexate, the permeability of which is among the lowest of the agents currently used clinically, are limited and the disproportionate increase in brain exposure, compared to tumor exposure, may alter the therapeutic index of many drugs.


1987 ◽  
Vol 66 (3) ◽  
pp. 345-351 ◽  
Author(s):  
Robert A. Solomon ◽  
Bennett M. Stein

✓ A series of 250 surgically treated cerebral arteriovenous malformations (AVM's) is presented, in which 22 lesions were located primarily in the thalamus and caudate nucleus. A standardized interhemispheric approach through the posterior corpus callosum and into the atrium of the lateral ventricle was utilized for the surgical removal of these AVM's. Total removal was confirmed by angiography in 18 patients; removal was subtotal in four cases. There were no deaths in this group of patients. Disturbances of recent memory pre- and postoperatively were seen in half of the patients, but most of these deficits were temporary. Other complications included: postoperative homonymous hemianopsia (six cases), transient hemiparesis (three cases), hemisensory loss (two cases), Parinaud's syndrome (one case), and recurrent hemorrhage 2 years after surgery (one case). All 22 patients returned to their previous occupations and are leading independent lives. The results of this experience indicate that thalamocaudate AVM's can be effectively treated by resection.


1980 ◽  
Vol 52 (5) ◽  
pp. 705-708 ◽  
Author(s):  
Laurence D. Cromwell ◽  
A. Basil Harris

✓ It is believed that surgical excision of arteriovenous malformations is the best treatment when technically feasible without causing significant damage to adjacent brain. The introduction of polymers or particulate emboli by catheter has been used either alone or as an adjunct in attempts to reduce the size of these lesions prior to surgery; however, it is seldom possible to embolize the entire malformation. The authors have used direct injection of a 50% mixture of bucrylate and iophendylate into the feeding arteries supplying the area at craniotomy, with success in three cases. The cases are described to illustrate the method.


1979 ◽  
Vol 51 (5) ◽  
pp. 621-627 ◽  
Author(s):  
Sean Mullan ◽  
Henry Kawanaga ◽  
Nicholas J. Patronas

✓ A useful variation of an established technique is described for embolization of cerebral arteriovenous malformations. Silastic sponge emboli that fit into No. 16, 17, and 18 stub adapters are passed through standard-sized transfemoral catheters. Of 28 treated patients, obliteration was regarded as very successful in 16. Partial success was achieved in four. Eight were regarded as failures because the reticulum was too large for these microemboli.


2001 ◽  
Vol 95 (2) ◽  
pp. 346-349 ◽  
Author(s):  
Francisco A. Ponce ◽  
Patrick P. Han ◽  
Robert F. Spetzler ◽  
Alexa Canady ◽  
Iman Feiz-Erfan

✓ Wyburn-Mason syndrome is a rare condition associated with multiple cerebral arteriovenous malformations. The disease, also called retinoencephalofacial angiomatosis, includes lesions of the retina, brain, and skin. This disorder stems from a vascular dysgenesis of the embryological anterior plexus early in the gestational period when the primitive vascular mesoderm is shared by the involved structures. The timing of the insult to the embryonic tissue determines which structures are affected. Extensions of the lesions vary widely but cutaneous lesions are unusual. Among reports in the literature, only three cases appear to have manifested without retinal involvement. The authors report the fourth case of Wyburn-Mason syndrome in which there was no retinal involvement and the first to involve neither the retina nor the face.


1981 ◽  
Vol 55 (5) ◽  
pp. 819-825 ◽  
Author(s):  
Harry V. Vinters ◽  
Gérard Debrun ◽  
John C. E. Kaufmann ◽  
Charles G. Drake

✓ There is controversy as to the possible toxic effects of isobutyl-2-cyanoacrylate (bucrylate) when this substance is used for purposes of therapeutic embolization. Two cases are presented in which cerebral arteriovenous malformations were resected, one 42 days and the other a year after bucrylate embolization. In both, pathological examination revealed a brisk intimal foreign-body giant-cell reaction wherever bucrylate was present in a vessel, along with chronic inflammation in the vessel walls and adjacent brain parenchyma. The findings are discussed in the light of other observations on the histotoxicity of bucrylate.


Neurosurgery ◽  
1985 ◽  
Vol 16 (4) ◽  
pp. 449-453 ◽  
Author(s):  
Jeffrey W. Cozzens ◽  
Leonard J. Cerullo

Abstract The carbon dioxide laser has recently received clinical acceptance in neurosurgical practice. There are, however, few studies reported in the neurosurgical literature, either clinical or experimental, concerning its safety or efficacy on a physiological level by comparison to a more conventional tool. This study is not a description of a surgical technique, but is rather a basic physiological comparison of two surgical instruments. In this study, 11 cats were pretreated with the protein-bound dye, Evans blue. A corticotomy was performed in one hemisphere with the carbon dioxide laser and in the other with a microbipolar coagulator and a sharp blade. The subsequent extravasation of dye was presumed to be proportional to the amount of blood-brain barrier disruption associated with each lesion. When effective power settings for the two devices were compared, the laser lesions had significantly less extravasation of blue dye. This indicated that there was less damage to the blood-brain barrier surrounding laser corticotomy than surrounding conventional bipolar coagulation and sharp dissection at comparable power settings for each modality.


Sign in / Sign up

Export Citation Format

Share Document