Photon counting detector CTA for prostate arterial evaluation during the workup for prostate artery embolization

PURPOSE: To evaluate small field of view (FOV) ultra-high spatial resolution pelvic photon-counting detector prostate CT angiograms (UHR PCD CTA) for identifying prostate arterial anatomy and extraprostatic anastomoses in patients undergoing workup for prostate artery embolization (PAE). METHODS: IRB-approved retrospective imaging and electronic medical record review of men who consecutively underwent UHR PCD CTA for PAE workup at our institution from 8/1/2022 to 12/1/2024. UHR PCD CTAs were evaluated by two vascular and interventional radiologists for main and accessory candidate prostatic arteries (PA/s) and anastomoses to penile, bladder, or rectal arteries. A main PA was defined as supplying the central gland and an accessory PA was defined as supplying the peripheral zone. PAs were categorized using the Carnevale classification. In patients who proceeded to PAE, digital subtraction angiograms (DSA) were retrospectively compared with UHR PCD CTA findings. RESULTS: UHR PCD CTA was obtained prior to PAE consultation for 50 men. We evaluated 100 pelvic sides, identifying 180 candidate PAs with a median of 3 candidate PAs per patient (mean, 3.6; range, 2-7). Overall, 56% (101/180) of candidate PAs were main and 44% (79/180) were accessory. Abridged Carnevale classifications: Type 5-21% (38/180). Eight accessory candidate PAs arose from the superior rectal artery. At least one candidate anastomosis arose from 40% (72/180) of candidate PAs. Of 95 total candidate anastomoses, 69 were extraprostatic (30 rectal, 20 bladder, 19 penile) and 26 were intraprostatic collaterals; 56% (53/95) arose from accessory and 44% (42/95) from main candidate PAs. Twenty-eight of 50 (56%) men underwent PAE, during which 72% (74/103) of available candidate PAs were selected, and prostatic supply was confirmed by DSA in 100% (74/74) of selected vessels. CONCLUSION: Small FOV UHR PCD CTA is useful in identifying candidate PA supply, as well as potential extraprostatic anastomoses, providing an arterial roadmap for PAE planning. Candidate PA supply was confirmed by DSA in all selected vessels among patients who proceeded to PAE.