Angiography

If symptoms of interruption of the vertebro-basilar circulation are present e.g., in cases of Jefferson fracture) vertebral angiography is mandatory. In severe subluxation of the atlanto-occipital joint damage to the vertebral artery is rather common. 

In basilar impression marked angulation of the vertebral artery can to be seen. An abnormal position of the PICA may identify the Chiari malformation. 

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Economic Aspects. The cardiovascular devices market is estimated to be approximately 2.9 biUion annually on a worldwide basis. This market can be further segmented as follows angiography and angioplasty, 644 x 10 arrhythmia control, 1500 x 10 cardiovascular surgery, 700 x 10 cardiac assist (intra-aortic balloon pump), 80 x 10 and artificial hearts, which are experimental. 

Table 2. Properties of Ionic Monomeric Radiopaques for Angiography and Urography...

Catheter angiography provides exquisite image detail and can visualize vessels as small as 0.1 mm in diameter, considerably smaller than those seen by CT- and MR-based vascular imaging techniques. Catheter angiography also provides high temporal resolution, which can help to distinguish arteries from veins and to detect prolonged intravascular stasis of blood. 

At the other extreme are those acute stroke patients who have no visible arterial occlusion whatsoever, presumably because their infarcts were due to lesions in small arteries that cannot be imaged, or because an embolus in a large proximal artery has broken up spontaneously. Several smdies (again using catheter angiography rather than CTA) have shown that such patients generally enjoy relatively favorable outcomes. 

Kucinski T, Koch C, Grzyska U, Freitag HJ, Kromer H, Zeumer H. The predictive value of early CT and angiography for fatal hemispheric swelling in acute stroke. Am J Neuroradiol 1998 19 839-846. 

Wildermuth S, Knauth M, Brandt T, Winter R, Sartor K, Hacke W. Role of CT angiography in patient selection for thrombolytic therapy in acute hemispheric stroke. Stroke 1998 29 935-938 [see comment]. 

Remonda L, Held O, Schroth G. Carotid artery stenosis, occlusion, and pseudoocclusion first-pass, gadolinium-enhanced, three-dimensional MR angiography— preliminary study. Radiology 1998 209 95-102 [see comment]. 

Heiserman JE, Drayer BP, Keller PJ, Fram EK. Intracranial vascular stenosis and occlusion evaluation with three-dimensional time-of-flight MR angiography. Radiology 1992 185 667-673. 

The effectiveness of catheter-based intra-arterial therapy to remove residual thrombus after IV rt-PA treatment is being tested in the Interventional Management of Stroke study (IMS-Ill). This study will randomize patients to 0.6 mg/kg IV rt-PA, followed by angiography with additional intra-arterial therapy as indicated, or IV full-dose rt-PA (0.9 mg/kg). A nonrandomized safety study suggested that intraarterial therapy, after 0.6 mg/kg IV rt-PA, could be accomphshed with acceptable rates of sICH. ° ... 

FIGURE 4.5 A 72-year-old man with medical history remarkable for hypertension and dyslipidemia presented with posterior circulation infarct (a). CTA and posterior circulation angiography (left vertebral artery injection) performed demonstrated severe mid-basilar artery stenosis (b and c). Left vertebral artery injection demonstrated near-complete reversal of the stenosis after a drug-eluting balloon expandable stent (Cypher, Cordis Johnson Johnson) was deployed (d). 

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