Embolization of an aortic arch pseudoaneurysm with coils and N-butyl-cyanoacrylate

Endovascular treatment strategies are evolving as viable alternatives for the treatment of aortic pseudoaneurysms. The present report describes an enlarging aortic arch pseudoaneurysm that was successfully treated with a combination of embolization with detachable coils and N-butyl-cyanoacrylate.

Controlled myocardial infarction induced by intracoronary injection of n-butyl cyanoacrylatein dogs: a feasibility study

Concentrated ethanol has been used to induce controlled myocardial infarct in patients with hypertrophic obstructive cardiomyopathy. We report the acute and early follow-up results of an alternative agent, n-butyl cyanoacrylate (n-BCA) glue, in a dog model. In 11 mongrel dogs, we injected n-BCA into different branches of the left anterior descending artery. Biplane left ventriculogram and coronary angiogram were performed before and after injection. In the surviving animals, we performed programmed stimulation (PS) to test for inducible ventricular tachycardia (VT) 48 days later. Following euthanasia, the removed hearts were studied with computer tomography (CT) and gross and histologic examination. Three dogs were lost before injection. Four dogs died within 2 hr to 4 days, and four animals survived 48 days. Accidental embolization of n-BCA into nontarget vessels was documented in four subjects. In the n-BCA-injected animals, homogeneous circumscribed scar was demonstrated by CT and histology. The glue was confined strictly to the tributary of the injected vessel, infiltrating arterioles of 14 mum. There was intense granulomatous reaction (GR) in the vessel wall and in the surrounding myocardium. Remote areas were unaffected. Monomorphic VT was not inducible with PS. We report a feasibility study of n-BCA injection to selected coronary arteries of dogs to cause controlled myocardial infarction. We demonstrated that the glue does not escape from the target artery through capillaries or small collateral vessels and thus produces a sharply demarcated and homogeneous scar, which is confined strictly to the supply zone of the injected vessel. Improvement of the delivery system is necessary to eliminate inadvertent embolization. Long-term follow-up is needed to study the GR induced by n-BCA.

Estimation of the remaining periodontal ligament from attachment-level measurements

AIM

Accurate assessment of the remaining area of periodontal attachment assists in determining the prognosis of a tooth. The aim of this study was to determine formulae to estimate the remaining area of periodontal attachment from attachment-level measures.

MATERIALS AND METHODS

Roots of 30 extracted teeth of each tooth type were coated with vinyl acetate solution and alpha-cyanoacrylate monomer to produce a membrane. The membrane was removed after guidelines were drawn to simulate various attachment levels. The root surface area on the apical side of each simulated attachment level was measured using image analysis software. The net or percent root surface area and corresponding attachment level data were fitted to a linear, quadratic, cubic, and exponential functions and a growth curve.

RESULTS

The linear function provided the most appropriate fit for the data. For net root surface area, a steeper slope was evident for tooth types with a larger mean total root surface area. For percent root surface area, a steeper slope was evident for tooth types with a shorter root length.

CONCLUSIONS

A linear function provides the most appropriate formula for estimation of the remaining area of periodontal attachment based on the attachment-level measurement.

Use of Indermil tissue adhesive for closure of superficial skin lacerations in children

BACKGROUND

The aim of this study was to assess the use of tissue adhesive for paediatric wound closure in a minor injuries environment.

METHODS

A n-butyl 2-cyanoacrylate adhesive formulation was used for the closure of traumatic skin lacerations in 56 children.

RESULTS

Tissue adhesive succeeded in approximating skin margins in all cases. No episodes of wound dehiscence were experienced. There were no incidences of wound infection.

CONCLUSIONS

This study indicates that this form of tissue adhesive can safely and effectively be utilised for traumatic superficial skin closure in children.

Arteriotomy closure by glued patch in the porcine carotid artery

BACKGROUND

A thoracoscopic approach to coronary bypass grafting warrants renewed search for facilitated vascular anastomosis methods. We reassessed tissue adhesion, sealing properties, and histotoxicity of iso-butyl-cyanoacrylate, in a simplified anastomosis model.

METHODS

In 12 Dutch landrace pigs, five arteriotomies were made in each carotid artery. The arteriotomies were closed by conventional microvascular suturing or by pericardial patch (Peri-Strips) and iso-butyl-cyanoacrylate. The animals were sacrificed at 2 hours (n = 2), 2 days (n = 5), and 4 weeks (n = 5). The arteries were examined by flow measurement, angiography, and histologic analysis.

RESULTS

The time required to close arteriotomies by conventional suturing was 257 +/- 43 seconds (mean +/- SD) and by glued patch 51 +/- 27 seconds (p < 0.001). In all arteriotomies covered by glued patch, complete hemostasis was obtained. At 2 days and 4 weeks, with both methods the same histologic results were observed. At follow-up, all carotid arteries were patent without stenoses.

CONCLUSIONS

Arteriotomy closure by glued patch was simple, fast, reliable, and without signs of histotoxicity. Adhesives deserve to be reconsidered as an alternative to suturing in closed chest beating-heart coronary surgery.

Study of the mechanism of insulin encapsulation in poly(isobutylcyanoacrylate) nanocapsules obtained by interfacial polymerization

In previous studies, insulin-loaded poly(alkylcyanoacrylate) nanocapsules were found to reduce the blood glucose level after oral administration to diabetic rats and dogs. The reduction of the glycemia induced by the nanocapsules was the same regardless of the insulin doses administered, but the effect appeared only after a delay of a few days. The purpose of this study was to investigate the mechanism of insulin encapsulation and the type of interactions that may exist between the polymer forming the nanocapsule wall and the insulin. The results of this study showed, based on the interfacial polymerization of isobutylcyanoacrylate, that the insulin molecule is not chemically modified during the nanoencapsulation process. In addition, no interaction between the poly(isobutylcyanoacrylate) and the insulin could be observed. The observed high encapsulation efficiency of intact insulin may be explained by the fact that the ethanol used in the preparation of the nanocapsules is responsible for the initiation of the interfacial polymerization of isobutylcyanoacrylate instead of the insulin. The zeta potential measurements suggest that insulin is located within the core of the nanocapsules. Thus the biological activity of the nanoencapsulated peptide and the high efficiency of insulin encapsulation achieved with this nanoencapsulation process cannot be explained by a specific interaction of the insulin with the polymer forming the nanocapsule's wall. It may be due, however, to the fact that the encapsulated insulin molecule is chemically intact and located within the oily core of the nanocapsules.

Embolization of spinal dural arteriovenous fistulae: results and follow-up

OBJECTIVE

To evaluate the efficacy of embolization for spinal dural arteriovenous fistulae (SDAVF).

METHODS

We reviewed 49 cases of SDAVF treated by embolization. An acrylic material was used in all except two cases. Variable stiffness microcatheters were used in 38 cases.

RESULTS

"Adequate" initial treatment was performed in 39 cases (80%). After the introduction of variable stiffness microcatheters, the initial success rate of embolization increased to 87% (33 of 38 cases). Eight patients underwent subsequent embolization for recurrence after "adequate" embolization. Causes of recurrence were collateralization in five cases, development of new fistulae in one, and unknown in two. Two additional patients developed subsequent aggravation of the symptoms, probably caused by progressive venous thrombosis, that responded to heparinization. Ten cases were initially "inadequately" embolized. Five of the 10 cases were treated before the introduction of variable stiffness microcatheters. Each of three of the remaining five cases had a common trunk from which the feeder and a spinal cord artery arose.

CONCLUSION

Embolization with an acrylic material should be the first choice of treatment for SDAVF, unless a spinal cord artery shares the same pedicle as the feeder of SDAVF. Subsequent aggravation of the symptoms after embolization can occur by various mechanisms. Therefore, periodic and long-term follow-up examinations are important.

Prophylactic oral administration of metabolically active insulin entrapped in isobutylcyanoacrylate nanocapsules reduces the incidence of diabetes in nonobese diabetic mice

Nonobese diabetic (NOD) mice develop an autoimmune disease with a long prodromal period and constitute a model for investigating the prevention of human type 1 diabetes. Since prophylactic insulin injections reduced the incidence of diabetes in NOD mice, we tested a new prophylactic strategy to prevent diabetes in NOD mice consisting of oral administration of insulin, protected in polyalkylcyanoacrylate nanocapsules from degradation in the gastrointestinal tract. In humans, this form of prophylactic insulin administration would be less constraining than insulin injections. Ninety female NOD mice were randomized at weaning and fed once a week (from 60 to 300 days of age) with insulin nanocapsules (100 U/kg) or empty nanocapsules. Within the group fed with insulin nanocapsules, the incidence of diabetes was reduced (38% vs 75%; P < 0.02), the onset of disease was delayed (P < 0.02), and the severity of lymphocytic inflammation of endogenous islets was reduced (P < 0.03). Although the oral treatment was stopped at 300 days of age, the incidence of diabetes at 360 days remained lower in mice previously fed insulin nanocapsules (P < 0.02). Previous feedings with insulin nanocapsules did not protect against cyclophosphamide-induced diabetes, since final incidence of diabetes (sum of the incidence during the initial 360 days and the further CY-induced incidence) reached the final incidence obtained in mice previously fed empty nanocapsules and treated with cyclophosphamide. Intestinal absorption of insulin nanocapsules was evidenced by HPLC separation of human insulin in NOD sera. During cotransfer, T splenocytes from mice fed insulin nanocapsules were able to reduce the capacity of T cells from diabetic donors to adoptively transfer the disease (P < 0.01). Antigens for islet-cell autoantibodies (ICA) in pancreata from both NOD groups were compared by immunofluorescence with the same ICA-positive human sera to ensure that differences were due to quantitative changes in antigen. These antigens, which could serve as an index of a possibly more extended antigen beta-cell rest, were decreased (P < 0.02) and pancreatic insulin content was reduced (P < 0.05) in mice fed with insulin nanocapsules, suggesting a mechanism of 'beta cell rest'. To summarize, early feeding with insulin nanocapsules reduces diabetes and insulitis in the NOD mouse model that mimics human type 1 diabetes. This may be due both to generation of cellular mechanisms that actively suppress disease and a decrease in antigens which makes beta cells less vulnerable to autoimmune aggression.

Formation and characterization of cyclosporine-loaded nanoparticles

The commercially available formulations of cyclosporine (cyclosporin A, CyA) are associated with acute hemodynamic changes that result in high nephrotoxicity. Among colloidal vectors, nanoparticles (NPs) are receiving much attention as potential drug carriers that would avoid the therapeutic risks of conventional formulations. Two different mechanisms for obtaining polymeric NPs loaded with CyA were studied with regard to their preparation and physicochemical characterization. Isobutyl-2-cyanoacrylate monomer (IBCA) was polymerized, whereas poly-E-caprolactone (PCL, a preformed polymer) was precipitated; both reactions took place in an aqueous medium containing Pluronic F-68 (polyoxypropylene polyoxyethylene block copolymer) as a surface active agent. The encapsulation efficiencies were 78.49 +/- 5.87 and 84.85 +/- 5.02%, respectively, and they remained stable over a wide range of drug concentrations. The polymeric NP had average sizes of 81 +/- 25 and 95 +/- 25 nm for poly-IBCA and PCL, respectively, as confirmed by photon correlation spectroscopy. Poly-IBCA NPs were built from oligomers with molecular weights of 157 to 2644 that joined to form a polymeric nanomatrix. In vitro activity of the drug and the carrier was tested by inhibition of lymphocyte proliferation induced by Concanavalin A. Drug-loaded PCL NPs and free CyA inhibited lymphocyte proliferation by 91.40 and 86.19%, respectively. However, drug-free NPs also exhibited statistically significant (p < 0.05) immunosuppressive activity.

[Long-term efficacy of endovascular embolization with silk particles and their effects on surrounding tissues in rabbits]

Long-term efficacy of therapeutic embolization with silk particles in rabbits was observed. The effectiveness of embolization and their histotoxicity on surrounding tissues were compared with dry dura mater particles, polyvinyl alcohol foam (i.e. Ivalon) and isobutyl 1-2-cyanoacrylate (IBCA). The results showed that the endovascular embolization with silk particles was almost as effective as that with IBCA and superior to dry dura mater particles or Ivalon. The toxicity of silk particles was similar to Ivaion, but less than IBCA and dry dura mater particles. The authors considered that silk particles are a good embolic agent at present.

Design of new formulations for topical ocular administration: polymeric nanocapsules containing metipranolol

To investigate the potential of polymeric nanocapsules for ocular delivery of beta-blockers, several formulations of polyisobutylcyanoacrylate and polyepsiloncaprolactone nanocapsules containing metipranolol base were developed. These formulations differed in the polymer forming the coating and in the type and volume of the oil encapsulated. Analysis of particle-size distribution, electrophoretic mobility, and loading efficiency of the nanocapsules revealed that the type of oil is the most important factor influencing these properties. From the in vitro release studies, we concluded that drug diffusion through a dialysis membrane is delayed as a consequence of the encapsulation process. However, the release profiles were not influenced by the polymeric coating, suggesting that drug release from these systems is governed mainly by the partition of the drug between the oily core and the aqueous release medium. Nevertheless, despite the inability of the polymer coat to control the release of the drug, its contribution to the stabilization of the emulsion was noted. Finally, the suitability of these formulations for ophthalmic administration was investigated. Although the pharmacologic response was not affected by the encapsulated metipranolol compared with the commercial eye drops, a drastic reduction of the drug's systemic side effects was observed.

Successful excision of a juvenile-type spinal arteriovenous malformation following intraoperative embolization. Case report

The case of a 57-year-old woman with a 14-year history of progressive paraparesis is presented. Selective spinal angiography revealed a juvenile-type spinal arteriovenous malformation (AVM) with a typical large size and rapid flow. The AVM was located primarily in the retromedullary space at the cervicothoracic junction. The AVM was successfully obliterated by intraoperative embolization using isobutyl-2-cyanoacrylate and surgical excision.

Nonsuture closure of arterial defect by vein graft using isobutyl-2-cyanoacrylate as a tissue adhesive

Nonsuture repair of intracranial blood vessel is still a challenging issue in neurosurgery. In this experimental study isobutyl-2-cyanoacrylate was used for nonsuture repairing of carotid artery to observe its histotoxicity. Isobutyl-2-cyanoacrylate was dropped over the edge of defect on carotid artery of rat under the surgical microscope and jugular vein was placed to cover the defect. Rats were divided in 6 group according to postoperative survival period (2, 5, 7, 14, 21, 28 days respectively). The carotid arteries were patent of all rats according to angiography and autopsy specimen. Histopathological results showed that: the changes are mainly inflammatory respons +, there was no necrotic tissue at any time the healing progress and no significant differences in the vein graft. Therefore isobutyl-2-cyanoacrylate is considered helpful and safe adhesive material for the nonsuture repair of blood vessel.

Evaluation of the apical leakage of isobutyl cyanoacrylate when used as a root canal sealant

The sealing properties of isobutyl cyanoacrylate were evaluated in extracted single-rooted human teeth. In the experimental group, instrumented root canals were obturated with isobutyl cyanoacrylate and gutta-percha by using the lateral condensation technique. In the control group instrumented root canals were obturated with gutta-percha only. The penetration of radioactive 131I was evaluated by an autoradiographic technique. No leakage was observed in the experimental group. This study shows that isobutyl cyanoacrylate is a good apical sealant.

Left main-stem bronchial stenosis complicating bronchial artery embolization

A 36-year-old patient was found to have severe left main-stem bronchial stenosis two years after bronchial artery embolization (BAE) for hemoptysis. Embolization-induced bronchial ischemia appeared to be the only potential cause for the observed lesions, and, to our knowledge, this constitutes the first report of late bronchial sequelae following BAE. Despite balloon-catheter dilatation of the stenosis, the severity of poststenotic lesions led to left pneumonectomy. The anatomic data further supported the hypothesis of a complication of BAE. Clinicians and radiologists should be aware of this potential complication of a widely used therapeutic procedure.

Inadvertent bucrylate pulmonary embolization: a case report

Detection of small, dense, rectangular opacities that follow the course of pulmonary vessels on chest radiographs should raise the suspicion of a prior therapeutic occlusion of the blood supply of a mass or of an arteriovenous fistula elsewhere with embolization of the occlusive material to the lungs. This article demonstrates the radiographic findings of such an occurrence in an asymptomatic woman.

[Embolization therapy of cavernous hemangiomas]

Hemangiomas are the most frequent tumors found in newborns, but mostly regress by the age of 7. Spontaneous progression and such complications as hemorrhage, disseminated intravascular coagulation (Kasabach-Merritt syndrome), threatened cardiovascular decompensation, and threatened interference with vital functions are rare and must be treated. Embolization therapy is a new therapeutic approach: vascular malformations and hemangiomas with pronounced arteriovenous shunts are treated by selective arterial embolization of the most peripheral branches of the supplying blood vessels. In contrast, lesions with a steady, slow blood perfusion can be treated by direct embolization of the cavernous system; further thrombosis and organization of the thrombus may lead to a permanent and complete occlusion of the hemangioma. If permanent occlusion cannot be achieved, temporary or partial thrombosis may allow curative plastic or reconstructive surgery, which would otherwise be impossible.

Contribution of hydroxyapatite to the tensile strength of the isobutyl-2-cyanoacrylate-bone bond

The bonding strength between bone and alpha-2-cyanoacrylate polymers, with or without the addition of powdered hydroxyapatite, was determined. The tensile strength of a bone-cyanoacrylate bond was measured for each polymer: 4.31 +/- 0.88 MPa (methyl-), 5.74 +/- 0.62 MPa (ethyl-), and 8.33 +/- 0.41 MPa (isobutyl-). The tensile strength of the isobutyl-2-cyanoacrylate bond increased to 12.03 +/- 0.72 MPa with the addition of 10% (w/v) hydroxyapatite before decreasing to 7.89 +/- 0.58 MPa on addition of 15% (w/v) hydroxyapatite. An optimal concentration of hydroxyapatite significantly increased the tensile strength of a bone-cyanocacrylate bond in vitro in a manner comparable to reinforced bone replacement materials.

Endoscopic closure of bronchopleural fistulas using a tissue adhesive

Bucrylate tissue adhesive has been found to be effective in achieving closure of surgically created bronchopleural fistulas in dogs. Success was obtained with both endoscopic and direct application. Clinical application of this method in one patient was successful [unpublished observations]. We believe that the speed, low risk, and cost-effectiveness of this approach justifies its further use in these difficult situations.

Cement coating of osteoarticular allografts in rats to prevent the immune response

Recently, more attention is being paid to the treatment of the articular surface defect in the young, active individual. Resurfacing or "shell" allografts are being considered as one of the alternatives for treatment. The immune response by the host may be the chief obstacle to the successful use of fresh osteoarticular allografts. Since proteins on the surfaces of allograft bone cells are considered to be the principal antigens eliciting the immune response, we hypothesized that mechanical masking of these cells by a biodegradeable blocking agent might prevent the immune response. Osteoarticular allografts of the distal femur were performed in rats and the cut surfaces of the graft were coated with cement before implantation. In a preliminary experiment, six biodegradeable cement materials were tried (bone wax, zinc polycarboxylate, collodion, fibrin adhesive, zinc oxide, and isobutyl-cyanoacrylate). Of these, the zinc oxide cement and isobutyl-cyanoacrylate were effective in inhibiting the immune response observed in control rat distal femur allografts. A second experiment was performed using nine rats with zinc oxide and nine rats with isobutyl-cyanoacrylate cements. These were compared with 20 control rats that had allografts without cement coating. Eighteen of the control rats (90%) developed an immune response, while only 22% (2/9) of the rats with zinc oxide coating and 33% (3/9) of the rats with isobutylcyanoacrylate developed an immune response. In a third experiment distal femur allografts were performed in 13 rats using only the liquid component of the zinc oxide cement.(ABSTRACT TRUNCATED AT 250 WORDS)

Artificial embolization with isobutyl-2-cyanoacrylate for the treatment of carotid-ophthalmic aneurysm

A large carotid-ophthalmic aneurysm was successfully obliterated by the combined treatment of clipping the aneurysmal neck and intraaneurysmal injection of isobutyl-2-cyanoacrylate. Reflux of the glue into the artery was prevented by temporary trapping of the carotid artery. The obliteration of an aneurysm with isobutyl-2-cyanoacrylate is an effective procedure in cases where clipping of the aneurysmal neck is not completed due to technical difficulties.

Isobutyl cyanoacrylate nanoparticles as a solid phase for an efficient immunoradiometric assay

The interaction of monoclonal antibodies and seric proteins with cyanoacrylic nanoparticles was investigated. A high binding capacity, rapid kinetics of adsorption as well as a good stability of the linkage were found. Furthermore, the immunoreactivity was conserved after coating antibody to nanoparticles. A new competitive immunoradiometric assay was also proposed for determination of alpha-fetoprotein amounts as low as 0.1 ng per assay.

Factors affecting the probability of conception after treatment of subfertile men with varicocele by transcatheter embolization with Bucrylate

Retrospective analysis of 100 patients treated for varicocele-associated infertility by means of transcatheter embolization with 2-isobutyl-cyano acrylate (Bucrylate, Ethicon Inc., Somerville, NJ) reveals that the age of the man and the duration of infertility do not influence the probability of pregnancy after treatment. Patients treated for subclinical varicoceles had the same probability of success as patients with larger varicoceles. The following factors were found to have predictive power as far as the posttreatment success rate is concerned: the coincidence of other disease interfering with the fertility of the man or woman, serum follicle-stimulating hormone concentration, total testicular volume, and pretreatment semen quality. Depending on the latter factors, the probability of conception varies between 8% and 80%. It seems possible to define certain subgroups of varicocele patients with poor, moderate, or good fertility prognosis.

Experimental carotid aneurysms: Part 2. Endovascular treatment with cyanoacrylate

Using our modification of the vein patch technique, we created 16 aneurysms in the common carotid arteries of dogs. After a stabilizing and healing period, these aneurysms were treated using percutaneous catheter techniques. Coaxial microcatheters were placed into the aneurysms, and a mixture of isobutyl 2-cyanoacrylate and tantalum dust was infused through the microcatheter using real time fluoroscopic control. Fifteen of the 16 aneurysms were successfully occluded; 1 was a failure because of total occlusion of the carotid artery. One human facial artery aneurysm was similarly treated. The ease and technical details of the treatment are discussed. Although the results are encouraging, we believe that it would be prudent to broaden the animal experimentation rather than to begin human use. Because no experimental aneurysm models are yet physiological, our results must be applied with caution to human intracranial aneurysms.

Rolandic arteriovenous malformations: improvement in limb function by IBC embolization

Three patients with arteriovenous malformations in the rolandic region and significant limb deficit showed virtually complete functional recovery after awake operative embolization of most of the malformations using isobutyl-2 cyanoacrylate. Two of these patients, with functionally useless hands, had sustained the deficits months earlier as the result of a specific brain-damaging event: one as a result of surgery and the other as a result of a hemorrhage. Both of these showed significant return of function during the awake operative embolization procedure. The other patient had had progressive leg weakness over a 2 year period. The theory of steal phenomenon as an explanation for progressive neurologic deficits in association with large arteriovenous malformations must be extended to explain apparently stable deficits after some brain trauma (surgery or hemorrhage). These results suggest that some patients with arteriovenous malformations and without clinical deficits who are near a critical level of "near ischemia" may be thrown out of balance by an acute interceding event.

Isobutyl-2-cyanoacrylate pulmonary emboli associated with occlusive embolotherapy of cerebral arteriovenous malformations

Three patients had cerebral arteriovenous malformations (AVM) treated by occlusive embolotherapy using isobutyl-2-cyanoacrylate (IBC). At necropsy two had asymptomatic IBC pulmonary emboli. The numbers of emboli and the size of pulmonary vessels occluded correlated roughly with an increasing frequency and volume of injectate made in the cerebral tissue. The extent of pulmonary vascular occlusion in one case suggests that pulmonary vascular hypertension could develop as a complication of this form of treatment.

Occlusion of a hepatic artery to portal vein fistula with bucrylate

A 49-year-old woman with cirrhosis and portal hypertension was evaluated for a portal-systemic shunt procedure following recurrent variceal hemorrhage. The preoperative visceral angiogram demonstrated a hepatic arterial to portal venous fistula, presumably a complication of a previous liver biopsy. The fistula was successfully closed using isobutyl-2-cyanoacrylate (Bucrylate) delivered through a flow-directed, calibrated-leak balloon microcatheter.

Percutaneous embolization of bony pelvic neoplasms with tissue adhesive

Eight patients with tumors of the bony pelvis underwent embolization with isobutyl-2-cyanoacrylate (IBCA). Five patients had primary bone tumors, of which 2 were malignant and 3 were benign; 3 patients had metastases to the bony pelvis from the thyroid gland, kidney, and femur, respectively. Embolization was performed to minimize blood loss during resection of a giant-cell tumor in one patient and insertion of a hip prosthesis in another who had metastatic renal carcinoma. It was also done prior to scheduled surgery in one of the patients with aneurysmal bone cyst, but healing was sufficient to cancel the operation; in the other patient, embolization was the only therapy. Palliative embolization was performed in 4 patients with malignant tumors after other means failed to control pain or slow progression. IBCA appears to be an efficient means of occluding the vessels feeding selected primary bone tumors and metastases.

Interventional radiology polymer update: acrylic

An overview of intravascular interventional embolic materials is presented. The physicochemical and biological properties of the monomer isobutyl 2-cyanoacrylate are discussed with specific details regarding therapeutic applications.

Transhepatic embolization in patients with acute variceal hemorrhage

Control of acute variceal bleeding by transhepatic embolization was investigated in 14 patients with alcoholic liver disease. In these patients hemorrhage was unresponsive to general supportive measures, intravenous vasopressin and balloon tamponade. Embolization was performed using Gelfoam and a synthetic polymer, bucrylate. Acute hemorrhage was arrested in 86 percent of patients. Rebleeding after transhepatic embolization occurred in 35 percent of patients. There were three deaths from intraabdominal hemorrhage related directly to transhepatic embolization (21 percent). Six patients (43 percent) left the hospital alive. In a group of cirrhotic patients in whom transhepatic embolization was employed after traditional modes of therapy had failed to control variceal hemorrhage, mortality and rebleeding rates were high.

[Trans-catheter embolisation of the spleen with butyl-2-cyanoacrylate. Experimental results and clinical application (author's transl)]

Partial and total trans-catheter embolisation of the spleen with butyl-2-cyanoacrylate-lipiodol in 23 dogs lead to partial necrosis and cicatrisation of the spleen after 3 to 5 weeks. The embolised vessels do not recanalise, but are by-passed by extra- and intra-splenic collaterals. In five animals there was a reduction in the number of erythrocytes; after embolisation there was increase in the number of leucocytes, whereas the thrombocytes were unchanged. The most common complication which occurred in five animals was a 1.5 to 2.5 cm. splenic abscess. The procedure was employed without success in one patient with bleeding oesophageal varices. The procedure was complicated by extensive necrosis of the gastric mucosa. Trans-catheter embolisation of the spleen has significant complications, despite strict asepsis and antibiotic cover. The main indication of the procedure is hypersplenism which cannot be treated surgically.

Definitive treatment of selected vascular injuries and post-traumatic arteriovenous fistulas by arteriographic embolization

Arteriographic embolization of carefully selected post-traumatic arteriovenous fistulas or bleeding vessels is a useful, safe alternative to direct surgical treatment, particularly in cases in which the involved vessel is not a critical artery and may be obliterated safely without fear of distal ischemia. The embolization procedure is readily accomplished at the time of diagnostic arteriography. It is ideally suited to treat lesions that are not readily accessible for surgical correction or in patients in whom surgery is thought to be too hazardous. The ease, efficacy and excellent long-term results achieved with arteriographic embolization and the lack of complications related to the procedure suggest that it should be used more frequently in treating carefully selected surgically accessible lesions.

Transcatheter embolization of the renal artery with bucrylate in renal carcinoma

In 5 patients with large renal carcinomas Bucrylate was injected into the renal artery. One to 3.5 ml Bucrylate were required to obtain occlusion of the arteries. At operation 14 to 38 days later the arteries were still occluded. One patient developed pulmonary embolism, other complications were of less importance. The main indication for the procedure is very large, highly vascularized carcinomas in the upper part of the kidney. Bucrylate seems to be a suitable embolus inducing agent.

Experimental nonsuture colonic anastomoses

A comparative study of sutured colonic anastomoses and anastomoses made by isobutylcyanoacrylate was performed in 60 rats. No difference in the strength of the anastomoses, as expressed by the bursting pressure, was found, and there was no difference in the frequency of adhesions or stenoses, provided the cyanoacrylate was meticulously covered by omentum. Histologic evidence of delayed healing was observed in the cyanoacrylate group; however, this did not seem to reduce the strength of the anastomosis. Provided it is covered with an omental tag, isobutylcyanoacrylate may prove to be a valuable adjunct to conventional suture techniques under special circumstances.

Preoperative embolization of renal tumors--comparison of different methods

Different techniques and materials for preoperative embolization of renal carcinoma have been assessed in 26 cases. The different methods used and compared were gelfoam fragments (10 cases), cyanoacrylate (4 cases), Gianturco stainless steel coil (3 cases) and the combination of gelfoam and the Gianturco device (9 cases). The method of choice appears to be the combination of gelfoam and the Gianturco device which allows excellent peripheral ischemia with complete occlusion of the main arterial trunks. Embolization is particularly useful in invading and hypervascularized renal tumors supplied by collateral blood vessels.

Catheter and material selection for transarterial embolization: technical considerations. II. Materials

In this second part of the report, the authors discuss the advantages and disadvantages of several embolization agents. These include Gelfoam, silicone spheres, polyvinyl alcohol foam (PVA), isobutyl-2-cyanoacrylate (IBCA), silicone fluid mixtures, and tantalum powder. The techniques employed and conditions under which these materials should be used are discussed.

Long-term radiographic-pathologic follow-up of patients treated with visceral transcatheter occlusion using isobutyl 2-cyanoacrylate (Bucrylate)

Visceral transcatheter occlusive therapy was performed with isobutyl 2-cyanoacrylate (Bucrylate) in 14 patients. Of 10 patients who subsequently died, postmortem examination in 6, performed 2--196 days post-embolization, showed only a mild histiocytic foreign body giant cell reaction to Bucrylate. The reaction was confined to the vessel lumina and did not involve the vessel walls or contiguous parenchymal tissues. Clinical and radiographic follow-up in the other 4 patients (range = 30--180 days) showed no evidence of untoward reaction to Bucrylate. No ischemic or inflammatory complications were observed in any of the peripheral organs.

Cyanoacrylate occlusion of a spinal cord arteriovenous malformation. Case report

✓ An arteriovenous malformation of the spinal cord was successfully obliterated by a percutaneous transcatheter technique using isobutyl 2-cyanoacrylate.

Tissue adhesives: new perspectives in corneal perforations

In corneal perforations associated with extensive progressive corneal disease, a technique using tissue adhesive closure of the perforation site and reformation of the anterior chamber before penetrating keratoplasty or conjunctival flap mobilization has been described. Over the past year, six eyes have been successfully treated in this manner. This method allows reformation of the eye under local anesthesia as an emergency procedure without incarceration or injury of the intraocular contents and without pain to the patient. The definitive surgical procedure can then be performed safely under retrobulbar anesthesia.

Palliative embolization of arterial renal tumour supply. Results in 10 cases

Palliative occlusion of the arterial renal tumour supply was performed in 10 patients and the follow up is reported. Nine of the patients had no subsequent nephrectomy. Spongostan (99% gelatin) was used as the embolic material in 4 patients with the addition of steel coils in 2. Bucrylate was used in 6 cases. Six patients are alive with survival rates presently ranging from 3 to 24 months after embolization. Improvement of the survival time cannot be estimated but local symptoms such as hematuria and pain may be treated in those patients with renal tumours who are not considered for surgery.