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Operator Learning Curve for Prostatic Artery Embolization and Its Impact on Outcomes in 296 Patients

  • Embolisation (arterial)
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To define operator learning curve inflection points for prostatic artery embolization (PAE) and their impact on technical efficiency, clinical outcomes, and adverse events.

Materials and Methods

Between May 2013 and May 2021, 296 consecutive patients with moderate-to-severe lower urinary tract symptoms, urinary retention, or gross hematuria from benign prostatic hyperplasia underwent PAE by an interventional radiologist without prior PAE-specific experience. Operator learning curves plotted procedure time, fluoroscopy time, contrast volume, and embolic endpoint data against sequential procedure number. Multiple regression analysis evaluated for improvements in these parameters, with segmented linear regression to detect learning curve inflection points. Linear and logistic regression evaluated for learning curve impacts on 6-month clinical outcomes and 90-day adverse events.


No baseline patient characteristic varied over the series apart from decreasing pre-procedural gland volume (P < 0.01). Multiple regression analysis demonstrated experience-dependent improvements in procedure time, fluoroscopy time, and contrast volume (P < 0.01), with corresponding learning curve inflection points at 76 (P < 0.01), 78 (P < 0.01), and 73 (P = 0.10) procedures. Embolic endpoints did not vary with experience (P > 0.05). Post-procedure reductions in International Prostate Symptom Score (21.5 ± 6.2 to 6.7 ± 4.7), Quality of Life score (4.5 ± 1.2 to 1.3 ± 1.2), post-void residual (190 ± 203 to 97 ± 148 mL), and gland volume (142 ± 97 to 76 ± 47 mL) were substantial (P < 0.01) but did not vary with experience (P > 0.05), nor did adverse event frequency/severity (P > 0.05).


Operator technical efficiency plateaued after 73–78 PAE procedures. Clinical improvements were substantial and adverse event frequency/severity low, and neither varied with experience. Operators without prior PAE-specific experience may perform PAE safely and effectively from the outset.

Level of Evidence

Level 2b, Cohort Study.

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Prostatic artery embolization


Lower urinary tract symptoms


Benign prostatic hyperplasia


Charlson comorbidity index


Body mass index


International prostate symptom score


Quality of life score


Prostate gland volume


Post-void residual


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Correspondence to Raj Ayyagari.

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Conflict of interests

Dr. Bhatia receives grants and personal fees from Merit Medical Incorporated, personal fees from Terumo Incorporated, personal fees from Mentice, grants and personal fees from Siemens Medical, stock holdings with Embolx Incorporated, and personal fees from Medtronic, outside the submitted work. All other authors have no conflicts of interest.

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Powell, T., Rahman, S., Staib, L. et al. Operator Learning Curve for Prostatic Artery Embolization and Its Impact on Outcomes in 296 Patients. Cardiovasc Intervent Radiol 46, 229–237 (2023).

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