Experience with bucrylate (isobutyl-2-cyanoacrylate) embolization of cerebral arteriovenous malformations during surgery

Stretched and sheared microcatheter retained after onyx embolization of infantile myofibromatosis

We describe a rare neurointerventional complication, namely a stretched and sheared microcatheter, extending 52 cm from its point of retention within an Onyx cast in an infant patient's neck mass, to the groin. The tumor was an unusual manifestation of infantile myofibromatosis and prior attempts at resection had proven impossible due to bleeding. Recommendations regarding microcatheter selection, diagnostic workup, and management of the ensuing complication are given.

Management of a retained catheter in an arteriovenous malformation. Case report

The long-term effects of retained catheters in patients are not well known; therefore, the clinical presentation may differ. The authors present the case of a 21-year-old man with a pseudoaneurysm of the left common femoral artery, which developed 3 months after a transfemoral microcatheter embolization of a cerebral arteriovenous malformation (AVM) in which the catheter was inadvertently glued into the AVM and was retained at the groin.

Trapped Microcatheter from Vessel Spasm: Safe Removal after Double Microcatheter Technique and Local Papaverine Infusion

In a child undergoing combined transarterial and direct percutaneous puncture embolization of an extensive and complex facial arteriovenous malformation, severe arterial spasm fixed a flow-directed microcatheter in an ethmoidal branch of the left ophthalmic artery. Multiple traction attempts failed to remove the microcatheter. After catheterization of the distal, post central retinal artery part of the same ophthalmic artery, with a second flow-directed microcatheter and following intraarterial papaverine injection through this second microcatheter, the fixed microcatheter could be removed without complication. This case demonstrates a technique that can be attempted before deciding to leave the microcatheter in the patient or to remove it surgically.

Glued Catheters during Embolisation of Brain AVMs with Acrylic Glue

SUMMARY

We evaluated the frequency and the side effects associated with gluing a piece of microcatheter in the feeder during embolisation of brain AVMs with acrylic glue. A retrospective analysis of 233 brain AVMs embolised with acrylic glue over a 15 year period has shown that 29 microcatheters were glued into the feeder. This represents 936 superselective catheterizations of different feeders followed by injection of glue. There was no side effect in 27 cases. Eight cases were operated upon a few hours or days after the complication occurred. The piece of tubing was removed in six cases. The reason for early surgery was the fear of extensive thrombosis of a major trunk (MCA or BA) or taking advantage of the catheter being still free in the cerebral vessel. In one case of temporal AVM, a Magic 1.5F coiled up into the distal basilar and PCA. In one case of left parietotemporal AVM, surgery was done one month after having glued a piece of tubing into the left MeA without side effect. The patient became hemiplegic and aphasic two hours after surgery. The thrombosed left MeA was reopened with Urokinase. The patient recovered with minor residual aphasia. The risk of side effects increases with the use of the Magic 1.5F that coils up into the vessel more easily than the Magic 1.8F. Leaving a piece of Magic catheter in the feeder to a brainAVM usually has no side effect. When there is a risk of thrombosis of a major trunk (MCA, BA) or when surgical resection is indicated, surgery should be done as soon as possibile because it is usually possible and easy to retrieve the piece of tubing from the intracranial circulation. The frequency of this complication has decreased since we starded using more diluted acrylic glue.

The surgical treatment of small deep intracranial ateriovenous malformations: a report of 85 cases

A series of 85 patients having what are defined as small, deep intracranial arteriovenous malformations (AVMs) is analysed in terms of presentation, investigation, treatment and outcome. This group of patients is taken from a consecutive series of 306 patients with AVM treated over a 20 year period. The anatomical distribution was as follows: cerebral hemisphere 54 patients, basal ganglia and thalamus 6 patients, brain stem and cerebellum 19 patients and deep dural 6 patients. Haemorrhage, both subarachnoid and intraparenchymal, was the predominant mode of presentation (71 of 85 cases). Other presentations were with epilepsy (5 cases), headache only (4 cases), progressive focal deficit (1 case) and mixed (4 cases). The vast majority of patients (71 of 85, 83.5%) were treated surgically: 67 by surgery only, 3 by surgery following partial embolisation and one with focussed irradiation after subtotal excision. The overall outcome in this group at 1 month was 27 (38.0%) improved (largely due to haematoma removal), 42 (59.2%) unchanged and 2 (2.8%) worse. One of the unchanged group died during the second month with pulmonary complications following prolonged impairment of consciousness. The two patients worse at 1 month (Gd I -> Gd II) returned to Gd I within 3 months. There were 3 patients treated non-surgically (2 by focussed irradiation and 1 by embolisation) while 11 patients were not treated because they declined treatment (3 cases), they died before treatment could be carried out (3 cases), or treatment was deemed inadvisable (5 cases). The results of surgical treatment in small deep AVMs are compared with those of other treatment modalities, in particular focussed irradiation. It is argued on the basis of these figures that surgery remains the best treatment for these lesions.

Cure, morbidity, and mortality associated with embolization of brain arteriovenous malformations: a review of 1246 patients in 32 series over a 35-year period

Published reports of cure, morbidity, and mortality associated with the embolization of 1246 brain arteriovenous malformations during the last 35 years were reviewed. Embolization resulted in cure in 5% of arteriovenous malformations. The cure rates of embolization were 4% in reports of 708 patients published before 1990 and 5% in reports of 538 patients published since 1990 (P = not significant). Temporary morbidity from embolization was 10%, and permanent morbidity was 8%. Permanent morbidity was 9% before 1990 and 8% since 1990 (P = not significant). Death after embolization of brain arteriovenous malformations occurred in 1% of patients. Mortality associated with the embolization was 2% before 1990 and 1% since 1990 (P = not significant). Long-term morbidity associated with the use of neurotoxic embolization materials is worrisome but has never been proven.

Neuropathological changes following occlusion of the superior sagittal sinus and cerebral veins in the cat

Superior sagittal sinuses (SSS) of 36 mongrel cats were occluded by polymer injection. Immediately prior to the occlusion, Evans-blue (EB) was administered intravenously. The cats were killed 1,3,6,12,24,72 and 120 h after sinus occlusion. Two sham-operated cats were killed 6 h and two 120 h after the operation. In 16 cats in which the occlusion was limited to the SSS, as well as in the sham-operated cats, no EB extravasation was present. However, ultrastructurally in two animals, the extracellular spaces were moderately enlarged, corresponding to increased permeability for water without opening of the BBB for proteins. In 20 cats in which cortical veins were occluded, in addition to the SSS, EB was extravasated. In nine of these cats, which had moderate oedema, EB-staining was present only in the cortex. In 11 cats with severe oedema, massive EB was extravasated. In nine of these cats, which had moderate oedema, EB-staining was present only in the cortex. In 11 cats with severe oedema, massive EB extravasation was observed also in the white matter. The U-fibre layer was free of EB, suggesting that the extension of oedema was blocked by this zone. Cats with severe oedema showed extensive haemorrhagic cerebral infarction widely, but not completely, overlapping with ischaemic necrosis, and corresponding to the differences in the territories of arterial supply and of venous drainage. Seven animals displayed haematomas in the parasagittal white matter. Electron microscopy (EM) showed damage to the endothelium of capillaries and venules with extravasation of platelets. In cats which survived longer than 24 h, the extracellular spaces were filled with proteinaceous transudate.(ABSTRACT TRUNCATED AT 250 WORDS)

Histopathological studies of a new liquid embolization method using estrogen-alcohol and polyvinyl acetate. Experimental evaluations with a model of cortical arterial cannulation in the canine brain

This experimental report evaluates the histopathological effects of a new embolization method using estrogen-alcohol (E-A) and polyvinyl acetate solution (PVac) as tested on 21 mongrel dogs. Three other animals treated with normal saline served as controls. All agents were introduced through an isolated cortical artery. Estrogen-alcohol induced immediate occlusion of small vessels (less than 20 microns), and then progressive obstruction of larger ones (200-300 microns) within several days. Animals treated with PVac showed vascular obliteration (greater than 100 microns) and moderate chronic fibrosis. The effects of embolization using E-A followed by PVac were found to have the combined advantages of both materials, showing diffuse occlusion of the vascular network with less tissue reaction. Hyalinization of embolized vessels with extensive fibrosis occurred afterward. For 6 weeks there was no evidence of recanalization or foreign body giant cell reaction. This study shows that E-A and PVac are capable of producing vascular occlusions with only mild tissue reaction. Because they are easily controllable and have no adverse effects, they may be suitable for intravascular application in the central nervous system.

Modified ethoxyethyl cyanoacrylate for therapeutic embolization of arteriovenous malformation

Aiming at alleviating the problems of using 2-cyanoacrylates as a material for therapeutic embolization, this experiment made some physical modifications by mixing contrast media. It was found that the physicochemical properties of 2-cyanoacrylates can be altered by changing the concentration and the composition of the contrast media added. A 50 wt% cyanoacrylate-50 wt% contrast medium mixture has enough radiopacity for the practical requirement for embolization. A mixture of 50 wt% (ethoxyethyl cyanoacrylate-5 wt% lactide/epsilon-caprolactone copolymer), 25 wt% lipiodol and 25 wt% tetrafluorodibromoethane provides a viscosity of 13.8 cP, a bonding strength of 14.9 kg/cm2, a set time of 6 s, and a spreading in canine blood of 33 mm. It was concluded that the mixture is much more satisfactory than the conventional cyanoacrylates as an embolus material in vitro. The results obtained by in vivo experiments and clinical trials so far suggest that the mixture is very promising as a material for embolization.

Intraoperative embolization of cerebral arteriovenous malformations

Nineteen patients with large cortical or deep seated cerebral arteriovenous malformation (AVM) were treated with intraoperative embolization using bucrylate (isobutyl-2-cyanoacrylate, IBC). In three cases of medium-sized AVM, the procedure was followed by a total excision of the lesion during the same operation. The results were excellent. In one case a hematoma and brain swelling following embolization necessitated total removal immediately afterwards. In eight patients embolization was carried out in two or three stages, to achieve a gradual obliteration of the shunt and to diminish the risk of postoperative brain swelling. Nevertheless, in three of these patients, postoperative hemiplegia was seen, which, however, improved considerably over a 1-2 year period. Complete occlusion of the shunt was obtained in only two patients. Seven patients underwent single-stage embolization, which resulted in partial obliteration of the AVM in six of them. In two of these, this treatment had been proposed for the accompanying symptoms of seizures and ischemic attacks. In all but one case the epileptic seizures decreased or disappeared completely after embolization. One patient suffered intracerebral bleeding three months after partial obliteration. Mortality was zero. It is argued that an alteration of the cerebral circulation with subsequent hyperemia is the most important sequela of rapid obliteration of large AVMs. Some details concerning the structure of cerebral AVMs are discussed.

The histotoxicity of cyanoacrylates. A selective review

Cyanoacrylates, a group of rapidly polymerizing adhesives, have found widespread uses in oral and general surgery as well as surgical subspecialties, for example as hemostatic and anastomotic agents. They have been utilized most recently as materials for embolotherapy of complex cerebral and extra-cerebral vascular anomalies. The histopathology that results from their deposition in human tissues is thus an important consideration, and the subject of this review. Particular attention is given to the fate of cyanoacrylates in cerebral lesions after iatrogenic embolization procedures. The apparent toxicity of these plastics on blood vessel walls is discussed in relation to experimental observations. It is imperative that clinicians who use this group of substances evaluate their potential functions in the light of the pathologic findings.