We typically first identify the aneurysm either in a CT scan, or, more commonly, in an MRI scan. If we find an aneurysm by CT or MRI scan, we then obtain an angiogram or arteriogram. At this time, the angiogram is the test that most accurately shows the aneurysm and its relationship to the surrounding arteries. At Johns Hopkins, we treat aneurysms using one of two methods, depending on the type of aneurysm. These two methods are microsurgical clipping and endovascular coiling.
Microsurgical clipping is the more established of the two techniques.
During microsurgical clipping, we perform a craniotomy and using the microscope occlude the base of the aneurysm with a specialized clip, thus preserving flow in the artery from which the aneurysm arises. The first aneurysm ever treated by surgical clipping was operated on at Johns Hopkins by Dr. Walter Dandy on March 3, 1937. Endovascular coiling is more recent and has been used in patients since 1991. During endovascular coiling, we pass a catheter through the groin up into the artery with the aneurysm and release platinum coils inside the aneurysm. The coils induce clotting of the aneurysm and in this way prevent blood from getting into it.