Endovascular treatment for stenosis of the intracranial arteries

Recently, intracranial artery stenosis has attracted more attention as a cause of atherothrombotic cerebral infarction than before due to the development of imaging technology such as MR angiography and 3D CT angiography. The frequency of intracranial stenosis is no less than extracranial lesions such as cervical carotid stenosis, and the rate of stroke recurrence between extra- and intracranial stenosis is almost equal. Based on the development of neuroendovascular therapy, over the last two decades, percutaneous transluminal angioplasty and stent placement have become feasible as treatment options for lesions of intracranial arteries. Several clinical trials have been published with favorable results, while novel specific devices have been developed for intracranial use. In Japan, reports of cases and series have been increasing despite being an off-label treatment yet to receive government approval. A consensus on indication, standard procedure, and perioperative management has been authorized between specialists. These results highlight the need for controlled clinical trials to determine the value of PTA/stent placement for intracranial stenosis.