Role of electrothrombosis in aneurysm treatment with Guglielmi detachable coils: An in vitro scanning electron microscopic study

BACKGROUND AND PURPOSE: In the 1990s, the introduction of the Guglielmi det achable coil (GDC) system in clinical practice was followed by extensive cl inical use of this endovascular device in the treatment of brain aneurysms. This technology is based on electrothrombosis and electrolytic detachment of platinum coils. Despite the extensive use of this treatment technique, t he role of electrothrombosis has not been fully investigated and clarified. An in vitro electron microscopic study of human blood was performed to elu cidate the role that electrothrombosis might play in triggering the biologi c response of thrombosis of the aneurysmal sac. METHODS: Human blood from five patients was used to fill plastic containers in which GDCs had been deposited. These five patients had subarachnoid hem orrhage and were similar in age and clinical presentation. Electron microsc opic studies were performed on GDCs that had been electrically charged and on GDCs that had not. RESULTS: All electron microscopic studies revealed that the electrically ch arged GDCs were covered by blood elements and fibrin adherent to the surfac e of the coil. Noncharged GDCs did not have deposits or adhesions of these blood constituents. CONCLUSION. These findings demonstrated that passage of electric current th rough the GDC induces attraction of blood constituents. This attraction may trigger a thrombotic reaction on the surface of the coil. The greater the time of current application, the more pronounced the cellular reaction and the deposition of fibrin and blood cells on the GDC.