Angiography And Orbital Interventions

FIGURE 9.10. Radiographs from views of a right internal carotid angiogram. (A) Anterior-posterior (AP) view shows a typical high-flow fistula from the right carotid artery to the cavernous sinus. (B) Lateral view: typically type A fistulas are treated endovascularly from the arterial side.

tient.22 23 In addition, there are case reports of ocular injuries due to deflection of small metallic fragments present in the orbits of sheet metal workers when these patients were placed in the magnet.24 Thermal

With the development of magnetic resonance angiography (MRA) and computed tomographic angiography (CTA), the use of catheter diagnostic angiography has diminished dramatically. Catheter diagnostic angiog-raphy is not commonly used for orbital tumor diagnosis other than for vascular lesions. This imaging technique, however, remains the examination of choice for evaluating some of the vascular pathologies, particularly carotid cavernous fistula. The cath-

FIGURE 9.11. Angiograms of a right internal carotid artery after placement of a detachable balloon: (A) AP view and (B) lateral view.
Greater Wing Sphenoid Images
FIGURE 9.15. Tip of microcatheter in cavernous sinus; microcoils at level of fistula.

eter angiogram is essential to classify the arteriovenous fistula and also determines the best treatment option.31'32 Angiography is briefly reviewed in this chapter because of its limited role in differential diagnosis of lesions occupying orbit-cranial space. Barrow and coworkers classify spontaneous carotid cavernous fistulas as follows:31

Type A: Direct high flow fistula between the internal carotid artery and the cavernous sinus (Figures 9.10, 9.11, and 9.12) Type B: Dural shunts between meningeal branches of the internal carotid artery and the cavernous sinus (Figures 9.13, 9.14, and 9.15) Type C: Dural shunts between meningeal branches of

FIGURE 9.13. A ^ type B fistula: (A) lateral angiogram and (B) en- the external carotid and the cavernous sinus larged lateral angiogram. Type D: Dural shunts between the meningeal branches of both the internal and external carotid arteries and the cavernous sinus

FIGURE 9.14. (A) Sheath placed into the superior ophthalmic vein. (B) Lateral view of microcatheter and contrast injection into the superior ophthalmic view and cavernous sinus. Radiographs of a right internal carotid angiogram after placement of a detachable balloon in the cavernous sinus to seal the fistula; the balloon was introduced from the arterial side.

FIGURE 9.14. (A) Sheath placed into the superior ophthalmic vein. (B) Lateral view of microcatheter and contrast injection into the superior ophthalmic view and cavernous sinus. Radiographs of a right internal carotid angiogram after placement of a detachable balloon in the cavernous sinus to seal the fistula; the balloon was introduced from the arterial side.

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