Embolization of cerebral angiomas by catheterization of cortical arteries

The combined management of cerebral arteriovenous malformations. Experience with 100 cases and review of the literature

A series of 100 patients treated for a cerebral arteriovenous malformation (AVM) is presented. Patients were admitted between 1985 and April 1992. Two groups are considered: the first group including 52 patients treated before the availability of radiosurgery (1985-1988), and the second group including 48 patients treated after the availability of radiosurgery (1989-1992). AVM's were classified in five grades according to the Spetzler's Grading System. Three techniques of treatment were used: surgical resection, intravascular embolization (with cyanoacrylate), and radiosurgery (linear accelerator). These three techniques were used either alone or in association, giving four types of management: surgical resection alone, embolization and resection, embolization alone, and radiosurgery (alone, or after embolization, or after surgical resection). From 1989 on, the availability of radiosurgery was responsible for the decrease of the "embolization and resection" group, which until then was predominantly used as well for low-grade (I, II, III) as for high-grade AVM's (IV, V). Overall, for the low-grade AVM's, the treatment of choice was surgical resection (79% of cases), with pre-operative embolization in one-half of these cases; the other low-grade AVM's were irradiated, with various combinations. For the high-grade AVM's, the treatment of choice was intravascular embolization (95% of cases), either alone, or followed by resection (45%) or radiosurgery (9%). Results were evaluated in terms of deterioration following treatment, in five groups: no deterioration (59%), minor deterioration (20%), long-lasting deficit (10%), major deterioration (5%), and death (6%). Overall, results improved after 1989: favourable outcome (no deterioration and minor deterioration) increased from 67% to 90%. Results were not related to the patients' age. More favourable results were obtained for low-grade AVM's (93%) than for high-grade AVM's (60%). For the low-grade AVM's the evolution from 1989 on (favourable outcomes increasing from 89% to 96%) occurred with the lowering of the mortality rate. For the high-grade AVM's, the evolution from 1989 onwards (favourable outcome increasing from 46% to 78%) occurred with the decrease of the cases with deficits. The angiographic results were strongly related to the management: 95% of complete eradication after surgical resection and 5% only after embolization alone. Concerning the results in irradiated cases, the follow-up is not long enough. The review of the neurosurgical literature since 1972 demonstrates progressive modifications in the therapeutic attitude as regards AVM's. The surgical management which was predominantly used at the beginning gave way progressively to a combined management, with a combination of embolization, surgery, and lately radiosurgery.(ABSTRACT TRUNCATED AT 400 WORDS)

The management of cerebral arteriovenous malformations

The presentation of 129 cases of cerebral angioma is reviewed. There were 4 main methods of presentation: haemorrhage, epilepsy, deteriorating neurological signs and headache. The fifth common method of presentation, heart failure, almost exclusively confined to infants, was not seen in the current series which includes no paediatric cases. Standard techniques of investigation principly angiography and CT scanning were used in diagnosis and the current indication for surgery was haemorrhage. The mortality rate per haemorrhage in the series considered in natural terms was 3.6%, neurological deficit as a result of the haemorrhage, either major or minor, occurred in a total of 8%, 4% each. Complete excision of the angioma was performed in 69 cases, although in 3 of these it was necessary to reoperate following postoperative angiography which was then used again to confirm total removal. There was 1 death in this series of radical removals, a mortality rate of 1.5%. Six cases however, showed significant neurological deterioration postoperatively, a major morbidity of 8.7%. From the period of observation of these cases and the instance of haemorrhage the annual bleeding rate would appear to be 4.2%. From follow-up of our cases where the lesion was not completely removed the re-bleeding rate would appear to be 2.6%.

Embolization of cerebral arteriovenous malformations with bucrylate

Forty-six patients with cerebral arteriovenous malformations (AVM's) were selected for embolization with bucrylate. These patients were assigned to three different groups. Group I consisted of 22 patients with nonresectable AVM's who were selected for embolization with a Silastic calibrated-leak ballon. In 16 or these patients, embolization was achieved, with partial obliteration of the AVM in 14 and complete obliteration in two. Five patients had subarachnoid hemorrhage caused by the balloon bursting and concomitant dissection of the feeding vessel. Four of these patients recovered completely and one died of a brain-stem hemorrhage. A permanent field defect was noted in five cases, and two patients had a transient mild neurological deficit. Group II consisted of 13 patients treated by intraoperative embolization. Complete obliteration by embolization was obtained in four cases, and complete surgical resection after embolization in five. Partial embolization with no surgical resection was achieved in five cases. Three of these patients had a permanent mild neurological deficit and two had transient deficits. There was no mortality in this group. Group III consisted of 11 patients treated by embolization with bucrylate using a new latex calibrated-leak balloon. This balloon has a higher malleability, and takes on the exact configuration of the feeder, with no risk of dissection. This balloon also permits delivery of the faster and larger injection of bucrylate to the arterial feeders of the AVM. Two AVM's were completely obliterated, and embolization was only partially successful in the other cases. Neurological complications consisted of incomplete field defects in two cases, slight memory loss in one case, and transient clumsiness of the arm and face in one case. Two patients have a catheter permanently glued in the malformation, with no neurological complication. There was no mortality in this group.

Homologous controlled-viscosity fibrin for endovascular embolization. Part II: catheterization technique, animal experiments

Part I of the present paper described the development of a substance for endovascular embolization from homologous fibrinogen, aprotinin, thrombin, metrizamide and CaCl2. Part II deals with the applicability of a controlled-viscosity fibrin mixture via different types of arterial catheters. In a flow-dynamic model the embolizing medium injected via a double syringe was shown to block a blood flow corresponding approximately to the flow encountered in cerebral angioma vessels. In the course of animal experiments the embolization of mesenteric arteries of rabbits showed the distribution of the embolizing medium to be dependent on its viscosity; the action of an embolizing medium applied by means of a double syringe was studied in the femoral arteries of rabbits. Scintigraphy was used to study the distribution of the substance in the body of the experimental animal after intravenous (i.v.) application; long-term studies of embolized auricular arteries in rabbits revealed parchment-like necroses after 5 to 10 days and the presence of radiopaque substances in the ear stumps after 6 weeks.

Treatment of cerebral arteriovenous malformations: a combined neurosurgical and neuroradiological approach

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.

[Development of therapeutic neuroradiology (author's transl)]

While therapeutic endovascular occlusions date from as early as 1904, it is in the last 20 years that therapeutic neutroradiology has come into its own. Progress has been made in four directions. (1) Embolization has developed from the original technique involving arteriotomy, through percutaneous methods, to present-day superselective catheterization. Concurrently, the materials used have been improved: from nonmalleable muscle and Silastic balls, to malleable Spongel and dura mater, and most recently to polymerizable fluid plastic substances. The possibility of obstructing very narrow vessels extends the range of indications of embolization. (2) Balloon catheters have been developed, first with nondetachable balloons (1971), more recently with detachable ones (1974). (3) Other techniques may be used to produce a therapeutic thrombosis, e.g., endovascular electrocoagulation and thermocoagulation. (4) Foreign bodies may be extracted safely by catheterization. Further development of techniques should ensure a growing importance for therapeutic neuroradiology in the future.