Advances in the treatment of complex cerebrovascular disorders by interventional neurovascular techniques. Treatment of complex cerebrovascular disorders, including intracranial aneurysms, carotid cavernous sinus fistulas, vertebral fistulas, arteriovenous malformations, atherosclerosis of brachiocephalic vessels, and arterial vasospasm, is being performed in selected cases by interventional neurovascular techniques. Recent advances in microballoon technology, permanent solidifying polymers, newer embolic agents, high-resolution digital subtraction angiography with road-mapping technique, and steerable micro-guide wires and catheters have greatly improved access in the distal intracranial circulation and markedly reduced the morbidity associated with these procedures. Interventional neuroradiology is emerging as an important adjunct to neurosurgery for selected cerebrovascular disorders. 