Endovascular Treatment of Vascular Pathology of the Head and Neck

Abstract

More than 20% of the patients evaluated or treated by our service have pathological processes involving the extracranial head, neck, or skull base. Endovascular techniques have proved effective in provocative testing of regional blood supply, presurgical embolization of vascular tumors, palliation fbr conditions such as epistaxis, arid, potentially, cure of cutaneous vascular lesions. This article describes some of the more common abnormalities that the interventional neuroradiologist may encounter and outlines the therapeutic strategies arid techniques used at our institution.Guiding catheters are required as part of the coaxial system used in the small vessels. These catheters range in size from 5F to 1OF and are usually thin walled and nontapered. The tip is positioned in the parent artery, where it acts as an introducer for the smaller microcatheter, which passes through a rotating hemostatic valve connected to the guiding catheter hub. The dead space is continuously flushed with heparinized saline to prevent clot formation. A threeway stopcock on the rotating valve sidearm allows the injection of contrast material through the guiding catheter for serial angiograms or roadmapping while the microcatheter is in place.Available microcatheters are either steerable with the use of a guidewire or are flow directed. The steerable systems are most frequently used in the treatment of head and neck lesions because: (1) the evenly distributed blood flow throughout the external carotid system makes flow-directed catheters impractical;(2) the external carotid vessels have mnultiple side branches and curves requiring a steerable system for selective catheterization;(3) the lumen is of sufficient size to accept a variety of embolic agents including particles, gelatin sponge pledgets, platinum microcoils, and liquid agents; and (4) detachable or hand-tied niicroballoons can be mounted on the distal tip for temporary or permanent vascular occlusion.Other catheters are available for special uses, including a double-lumen test occlusion catheter used in t.emporary occlusion testing of larger arteries (see Provocative Testing section below).