Digital subtraction angiography in cerebrovascular disease: current practice and perspectives on diagnosis, acute treatment and prognosis

An important factor in making a recommendation for treatment of a patient with arteriovenous malformation (AVM) is to estimate the risk of surgery for that patient. A simple, broadly applicable grading system that is designed to predict the risk of morbidity and mortality attending the operative treatment of specific AVM's is proposed. The lesion is graded on the basis of size, pattern of venous drainage, and neurological eloquence of adjacent brain. All AVM's fall into one of six grades. Grade I malformations are small, superficial, and located in non-eloquent cortex; Grade V lesions are large, deep, and situated in neurologically critical areas; and Grade VI lesions are essentially inoperable AVM's. Retrospective application of this grading scheme to a series of surgically excised AVM's has demonstrated its correlation with the incidence of postoperative neurological complications. The application of a standardized grading scheme will enable a comparison of results between various clinical series and between different treatment techniques, and will assist in the process of management decision-making.

Intracranial saccular or berry aneurysms are common, occurring in about 1-2% of the population. Unruptured intracranial aneurysms are increasingly being detected as cross-sectional imaging techniques are used more frequently in clinical practice. Once an unruptured intracranial aneurysm is detected, decisions regarding optimum management are made on the basis of careful comparison of the short-term and long-term risks of aneurysmal rupture with the risk associated with the intervention, whether that be surgical clipping or endovascular management. Several factors need to be carefully considered, including aneurysm size and location, the patient's family history and medical history, and the availability of an interventional option that has an acceptable risk. The patient's knowledge that they have an unruptured intracranial aneurysm can lead to substantial stress and anxiety, and their perspective regarding treatment, after hearing an unbiased appraisal of the rupture risks and the risk of interventional treatment, is of the utmost importance. Controversy remains regarding optimum management, and thorough assessments of the risks and benefits of contemporary management options, specific to aneurysm size, location, and many other aneurysm and patient factors, are needed.

The aim of this updated statement is to provide comprehensive and evidence-based recommendations for management of patients with unruptured intracranial aneurysms.