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Experimental catheter obstruction of the left gastric (coronary) vein was explored in 10 dogs. Using a transjugular approach, the liver was punctured and the portal vein catheterized. Coaxially introduced catheters were then used to catheterize selectively and produce an intravascular obstruction (tamponade) of the gastric coronary vein. Ballon catheters were used for a temporary occlusion. Injection of a tissue adhesive, isobutyl 2-cyanoacrylate, was used for a definitive obliteration. The achieved results show the anatomical feasibility of this approach and give good perspective for development of a clinical method for percutaneous intravascular tamponade of the bleeding gastroesophageal varices in cirrhotics.

Transcatheter arterial embolization is an interesting technique; its usefulness in urology has not yet been well assessed. The properties and characteristics of some embolic materials among the more commonly used were investigated by means of a new experimental model, i.e., transcatheter embolization of rat kidney. Autologous clots and Oxycel were found to give a transient embolization, whereas Gelfoam, barium, and cyanoacrylates did not allow recanalization or revascularization. Only barium was found in venous vessels. The findings are discussed in view of the clinical application of the embolic materials considered.

Arteriovenous fistula models were created of plastic and in dogs, allowing exploration of the intraarterial use of tissue adhesive, isobutyl cyanoacrylate. A delivery system utilizing superselective coaxial catheterization was developed on the model. Carotid artery to external jugular vein shunts constructed in 19 dogs provided a suitable in vivo model. Using varied injection techniques, the shunts were occluded in 17 of 17 treated animals. Three dogs subsequently died because of embolization to the lungs and one carotid artery was occluded. Techniques to avoid these complications were devised. Refinement of the intraarterial use of these adhesives will offer us another mode of treatment of vascular abnormalities.

In quest of an endarterial treatment for intracranial arteriovenous malformations and fistulas, a microcatheter which can be flow-guided into third- and fourth-order branches of the intracranial arteries was developed. This permits controlled deposition of a vascular occlusive polymer (isobutyl-2 cyanoacrylate). Goals and experimental techniques are reviewed and clinical experience on the first 25 patients is presented. Complications included one stroke and three catheters glued in place, but refinements in technique have permitted avoidance of complications over the 14 months before this report.

A case of frontal arteriovenous malformation, embolized using a new balloon catheter technique, was reported. During liquid embolization of the main feeder from anterior cerebral artery, middle cerebral artery was temporary occluded with another balloon catheter, to decrease blood flow from branches of middle cerebral artery. About 90% of the AVM could be obliterated by this technique.

Balloon catheter and embolization techniques continue to gain importance in the therapy of cerebral and spinal vascular malformations. These methods are applied either preoperatively to improve outset conditions for the operation or as an independent therapeutic measure to partially or completely bypass the malformation. So far the balloon catheter and embolization techniques are applied only within a limited field. Nevertheless, this fairly recently developed method is already indispensable in the therapeutic repertory. There are as yet no generally acknowledged principles with regard to indications for these procedures. Therefore, neurologists, neurosurgeons and neuroradiologists have to be included in the process of decision making.

An attempt at transfemoral transarterial balloon occlusion of a high-flow spontaneous carotid-cavernous fistula was unsuccessful because the carotid artery rent was too small for this approach. During a subsequent transvenous approach to the cavernous sinus through the jugular vein, the inferior petrosal sinus was perforated. A minor subarachnoid hemorrhage occurred before the tear could be sealed by the deposition of three Gianturco coils in the vein. The patient was taken to the operating room for emergency obliteration of the fistula and petrosal sinus in order to remove the risk of further hemorrhage. Under the guidance of intraoperative digital subtraction angiography, isobutyl-2-cyanoacrylate was injected directly into the surgically exposed cavernous sinus. Successful obliteration of the fistula was achieved with preservation of the carotid artery, and the angiography catheter was removed safely from the petrosal sinus. Although initially after surgery the patient had nearly complete ophthalmoplegia, at her 1-year follow-up examination she had normal ocular motility and visual acuity. The transvenous approach to the cavernous sinus and alternative methods of treatment of carotid-cavernous fistulas are discussed.