It has been widely accepted that the detachable balloon catheter technique is the treatement of choice in thecarotid-cavernous fistula and in the unclippable giant aneurysm at the cavernous or petrous portion of theinternal carotid artery. The authors successfully treated one case of the carotid-carvernous fistula and one caseof giant aneurys, located in petrous portion of the internal carotid artery using Debrun's latex datachableballoon catheter technique. In thecase with carotid-cavernous fistula, the only fistula was occluded with adetachable balloon, presserving the intrenal carotid artery. In the aneurysm case, both internal carotid arteryand aneurysm itself were completely occluded with 3 latex detachable balloons. Both patients have nocomplications. The authors will describe and discuss the Debrun's latex detachable balloon catheter technique.