073 - Anatomic and Procedural Considerations for Geniculate Artery Embolization
Purpose: Geniculate artery embolization (GAE) is a minimally invasive intra-arterial intervention that selectively targets geniculate artery branches corresponding to an area of knee pain. The principle in its mechanism of action is to curtail geniculate arterial supply of proinflammatory mediators that contribute to synovitis and joint vascularity. GAE is technically challenging due to the variations in vascular anatomy and risk of nontarget embolization. For example, one of the more concerning complications include skin ulceration and necrosis from inadvertent embolization of cutaneous branches arising from the proximal genicular branches. Therefore, it is important for the interventional radiologist to master geniculate artery anatomy and to be equipped with procedural pearls to minimize adverse events.
Material and Methods: GAE can be used for pain relief from hemarthrosis or osteoarthritis. GAE can also be considered for preoperative tumor embolization affecting the osseous or soft tissue components near the knee. Vascularity is divided into the three compartments of the knee, and the goal of the procedure is to target two to three hypervascular vessels per compartment to preserve vascularity to the joint capsule.
Results: There is limited but ongoing research regarding geniculate artery anatomy, which is known to have variable branching patterns. Ergo, initial angiography is critical for preprocedural planning. For example, genicular branches may be obscured by a knee prosthesis, highlighting the importance of serial oblique projections/angiography to better delineate vasculature. Having the patient identify his or her area of maximal pain and marking the site with an external radiopaque marker can help correlate a synovial blush or hyperremia to the area of concern, which is likely to occur near said marker. Application of an ice pack to the knee during the procedure and use of larger embolic particles can also reduce complications from non-targeted embolization. High-yield clinical pearls will be discussed via case-based format.
Conclusions: As GAE grows in popularity, particularly for its palliative potential in the setting of osteoarthritis, IRs need to have expert knowledge of the knee’s vasculature to optimize both technical and clinical outcomes.