The Pena-Collateral Spear Technique during Prostatic Arterial Embolization

• To recognize the application of the Pena-Collateral Spear Technique to avoid non-target embolization to the glans penis


• To describe the anatomy and procedural technique of the Pena-Collateral Spear Technique


• To recognize the common anatomical variations of the prostatic artery

Prostatic arterial embolization (PAE) is a minimally invasive treatment for symptomatic benign prostatic hyperplasia (BPH). Identifying collateral anastomoses of the prostatic artery is vital during PAE to avoid non-target embolization complications like ulceration and necrosis of the glans penis. {1} Although protective coil embolization can be used, the small and tortuous nature of these pena-collateral connections often makes access difficult or impossible.

This educational exhibit demonstrates the Pena-Collateral Spear technique, using a needle to temporarily block intraprostatic collaterals connected to the dorsal penile arteries during administration of the embolic material. 

Clinical Findings/Procedure Details:

Digital subtraction angiography (DSA) assesses prostatic arterial vasculature and identifies pelvic and intra-prostatic anastomoses. The Pena-collateral connection to the dorsal penile artery is typically midline, posterior to the pubic symphysis, on the anterior surface of the prostate gland. Cone-beam CT (CBCT) provides 3D visualization for planning. A 22G spinal needle is inserted through the pubic symphysis to occlude the communicating artery. Occlusion of this artery is confirmed by DSA and CBCT by the absence of contrast in distal branches. Bilateral prostatic arterial embolization then proceeds without complications, and the needle is removed at the end of the procedure.

Conclusion and/or Teaching Points:

The Pena-Collateral Spear technique in PAE occludes collateral circulation to the glans penis, preventing nontarget embolization and complications like ulceration and necrosis of the glans penis. This technique reduces the time of the procedure and in turn, can reduce radiation and contrast dose. The alternative to this procedure would be a coil embolization of the collateral circulation which also adds to the overall cost of the procedure.