Utility of 4D CT Technology During Prostate Artery Embolization (PAE)

The Canon Medical Alphenix 4D CT system combines two complimentary imaging modalities within the same environment - a sliding computed tomography (CT) scanner system with a state-of-the-art interventional fluoroscopic C-arm. This enables utilization of CT and fluoroscopic images during diagnostic and therapeutic interventions during the same procedure.
This potentially leads to more accurate image-guided interventions with reduced procedure time, providing on-demand true CT imaging during interventional procedures. ^{1, 2}

BPH, sometimes referred to as ‘an enlarged prostate’, is one of the most common medical conditions in older men, effecting 70% of men in their 70s and 80% of men in their 80s.³ Recently, Prostate Artery Embolization (PAE) was recommended by four multidisciplinary medical societies as a “valuable minimally invasive option for patients who cannot tolerate or who have failed medical therapy, and those who are poor surgical candidates or refuse invasive surgery.”⁴ Detailed knowledge of prostatic arterial anatomy is necessary during PAE in order to minimize the risks of ‘non-target’ embolization that can cause ischemic complications to major pelvic organs, such as the urinary bladder, rectum and penis.⁵ Thus, identification of the prostatic artery origin as well as collaterals supplying pelvic viscera, is paramount.

Procedure: Via right common femoral artery approach, both prostatic arteries (PA) were catheterized using a 2.4Fr microcatheter. The left PA (LPA) arose from the obturator artery and a clear intra-prostatic penile collateral was seen during Angiography (Figure 2). After successful coil embolization, the microcatheter was retracted into the main LPA and pelvic CTA was performed after hand injection of 3 cc contrast and 5 seconds delay (120kV, ^SUREExposure, 0.5s rotation time, 0.5 mm x 80, AIDR* 3D) using the 4D CT system. CT imaging was helpful for identifying persistent penile collateral (Figure 3) which was subsequently successfully coil embolized (Figure 3C). After retracting the microcatheter into the main LPA, 5 cc diluted embolic material (2cc 300-500 μm Embosphere^® microspheres in 9 cc saline and 9 cc contrast) was delivered into the LPA under fluoroscopy. The right PA (RPA) was also successfully embolized with 5 cc of diluted embolic material, for a total of 10 cc. No access site or post-procedure complications were seen.

History: A 80-year-old man presented in urinary retention from long-standing BPH with a left total hip arthroplasty and was referred for PAE.

Procedure: Via right common femoral artery approach, both tortuous internal iliac systems were selected and both PAs were catheterized using a 2.4Fr microcatheter. Pelvic CTA of each PA was performed after hand injection of 3 cc contrast and 5 seconds delay (120kV, ^SUREExposure, 0.5s rotation time, 0.5 mm x 80, AIDR 3D) using the 4D CT system. Intraprocedural CT imaging was helpful for being able to exclude intra-prostatic penile collaterals in addition to evaluating the entire enlarged prostate even in the face of the significant streak artifact from the left total hip arthroplasty (Figure 4, 5). Successful embolization was performed under fluoroscopy with a total of 15 cc diluted embolic material (2cc 300-500 μm Embosphere^® microspheres in 9 cc saline and 9 cc contrast) was injected. No access site or post-procedure complications were seen.

Outcome: The patient successfully passed voiding trial at 6 week follow up with mild LUTS (IPSS 6; QoL 1) post catheter removal.