Photon Counting Detector CTA for Prostate Artery Evaluation Prior to Prostate Artery Embolization

To evaluate the use of small field of view (FOV) high spatial resolution (0.2 mm slice thickness) photon-counting detector (PCD) prostate CT angiogram (CTA) for delineating prostate arterial anatomy in patients undergoing workup for prostate artery embolization (PAE).

Materials and Methods: In this IRB-approved study, imaging and electronic medical record review of men who underwent pelvic PCD prostate CTA as part of PAE workup at our institution from 2022 to 2024 was performed. PCD prostate CTAs were evaluated prospectively and independently by two vascular and interventional radiologists for prostate arterial supply, and consensus was achieved in all cases using the Carnevale PA classification. Candidate anastomoses to penile or rectal arteries were identified. In patients who went on to PAE, conventional angiograms were retrospectively compared with PCD CTA for confirmation of prostate arterial supply.

Results:

PCD prostate CTA was obtained prior to PAE consultation for 33 men (mean age 75y; range, 53–98y). We evaluated 66 pelvic sides, identifying 112 candidate PAs (cPAs) with a median of 3 cPAs per patient (mean, 3.4; range, 2–7). cPAs classified as follows: Type 1 – 32% (n = 36); Type 2 – 16% (n = 18); Type 3 – 15% (n = 17); Type 4 – 19% (n = 21); Type 5 – 18% (n = 20). Type 5 cPAs originated from the superior rectal artery in 6 cases on PCD CT and were confirmed angiographically in 3 cases. To date, 64% of patients (n=21) have gone on to PAE and main prostatic arterial supply at PCD CTA was confirmed at conventional angiography in all cases (100%). No non-target embolization occurred.

Conclusion:

High spatial resolution (0.2 mm slice thickness) PCD prostate CTA can detect the origin and course of prostatic arterial supply with high diagnostic accuracy in patients undergoing workup prior to PAE. Compared to cone beam CT performed intra-procedurally, PCD prostate CTA can delineate PA anatomy pre-procedurally, allowing for informed consultations, procedure planning, and identification of candidate extra-prostatic collateral vessels for evaluation at the time of PAE. Further work is needed to determine if the prostate arterial anatomy information from pre-procedure PCD prostate CTA can reduce PAE procedure time and improve clinical outcomes of PAE.