Trisacryl gelatin microspheres for therapeutic embolization, II: preliminary clinical evaluation in tumors and arteriovenous malformations.

PURPOSE To evaluate an embolic agent that is precisely calibrated, perfectly spherical in shape, and soft but nonresorbable for use in the embolization of vascular disease of the head, neck, and spine in humans. METHODS We used supple, hydrophilic, and calibrated trisacryl gelatin microspheres 200, 400, 600, 800 and 1000 microns in diameter for superselective embolization in 105 patients (27 tumors, 14 facial arteriovenous malformations [AVMs], 37 spinal cord AVMs, 21 cerebral AVMs, and 6 miscellaneous diseases). We used particles in 200 to 600 microns in diameter for tumors and for facial AVMs, particles 400 to 600 microns in diameter for spinal cord AVMs, and particles over 1000 micros in diameter for cerebral AVMs. RESULTS Delivery of the embolic material was easy: microspheres did not aggregate and catheters did not become obstructed by particles. It was possible to control the embolization through precise accounting of the amount of microspheres and matching of the particle size to the size of the pathologic vascular network. CONCLUSION The microspheres are easy to use and allow precise control of the embolization procedure. Their physical characteristics make them a safe embolic agent.