Selective conventional arteriography and computed tomography with and without contrast infusion: minimal requirements for the assessment of transient ischemic attacks.

The authors report two unusual cases referred for extracranial bypass surgery. These patients presented with symptoms of transient ischemic attacks (TIAs) and demonstrated the necessity of conventional selective angiography and computed tomography (CT), with and without contrast infusion, as part of the preoperative assessment. The authors discuss how digital subtraction angiography alone is inadequate and how CT without contrast enhancement may fail to visualize lesions that may exhibit TIA-like symptoms. In the face of the multiplicity of preoperative tests used to evaluate patients with TIA symptoms, the authors stress the importance of selective conventional angiography and CT with and without contrast administration.