IR Quarterly
IR Quarterly
By Nassir Rostambeigi, MD, MPH
Inside Access: Standardizing PAE techniques
Rostambeigi N, et al. Standardized Technique for Prostatic Artery Embolization: A Delphi Consensus Study on Optimized Methods and Emerging Concepts. JVIR, 2025;37.
In this Inside Access interview, JVIR author Nassir Rostambeigi, MD, MPH, discusses the international consensus effort to standardize prostatic artery embolization techniques and improve patient outcomes.
Tell us about you, your team, and your institution.
Nassi Rostambeigi, MD, MPH: I am an interventional radiologist at Washington University in St. Louis, Missouri. At our institution, we have developed a robust prostatic artery embolization (PAE) service line. Like other leading centers, our program has achieved considerable success, reflecting the strong safety profile and clinical effectiveness of this procedure.
The work featured in JVIR represents a multi‑institutional collaboration, bringing together world‑recognized experts in PAE from centers across the United States, South America and multiple countries in Europe. This international effort highlights a shared commitment to advancing PAE practice, establishing high‑quality standards and improving outcomes for patients worldwide.
Why did you pursue this topic?
Dr. Rostambeigi: The nationwide and global expansion of PAE service lines has naturally introduced considerable variability in how the procedure is performed. Such heterogeneity can influence both the effectiveness and safety of PAE, particularly given the degree to which procedural nuances shape clinical outcomes. As the PAE procedure has grown and become more prevalent, the field is now well positioned to establish a unified, expert‑driven consensus. To address this need, the GEST Research Committee undertook a structured initiative to develop a comprehensive guideline.
The committee selected a panel of international experts, and as the primary author, I created an initial draft, which was then circulated in multiple rounds of rigorous discussion with the panelists to refine and reconcile differing perspectives. I held one-to-one discussions which were anonymous to others, so that the input stays unbiased and non-influenced by other votes. This iterative, collaborative process ultimately resulted in a consensus guideline intended to reduce practice variability, support procedural safety and align global standards for PAE.
What are the key takeaways from your research?
Dr. Rostambeigi: Our research highlights several essential points for ensuring reproducible outcomes for PAE. First, successful PAE requires meticulous preprocedural planning and a thorough understanding of pelvic arterial anatomy, which remains the cornerstone of the procedure.
The article further outlines a structured sequence of procedural steps—including preprocedural imaging, antibiotic regimens, arterial access selection and device choice for catheterization and embolization.
Moreover, a detailed systematic description of strategies to prevent non‑target embolization is outlined. These recommendations reflect broad agreement among the panelists and serve as a practical framework for clinicians.
Finally, the guideline includes a dedicated section on emerging or controversial concepts that warrant further investigation and research. These include novel approaches such as the use of permanent liquid embolic agents and the coil‑out technique, both of which represent potential advancements in improving long-term outcomes. These areas highlight opportunities for continued research as the field of PAE continues to evolve.
How might this research influence treatment, practice, or clinical processes in interventional radiology?
Dr. Rostambeigi: A key achievement of this work is the high level of agreement reached among experts from 14 international centers on most procedural steps involved in PAE. This strong consensus underscores the reliability of the recommendations and supports the adoption of these standardized steps to promote consistent and favorable outcomes across diverse practice environments.
The guideline also emphasizes the importance of adhering to established techniques to prevent non‑target embolization, an essential aspect of procedural safety. The paper provides detailed, practical guidance on these techniques as well as on the devices that can assist in minimizing risk, thereby offering clinicians a clear framework for improving procedural precision.
Despite the substantial evidence supporting safety and efficacy of PAE, important knowledge gaps remain. These gaps highlight the ongoing need for further investigation, continuous quality improvement and the maintenance of thorough patient registries. Such efforts will be critical for advancing the field, refining best practices and informing future innovations in interventional radiology.
What key technical steps do experts agree are most important for performing safe and effective PAE?
Dr. Rostambeigi: Anatomy, anatomy, anatomy. Experts unanimously highlighted that the foundation of safe and effective PAE is a comprehensive and detailed understanding of pelvic vascular anatomy. Mastery of common prostatic artery origins as well as recognition of anatomic variants is essential, and this principle cannot be overemphasized.
In addition, the following technical steps reached strong consensus among the panelists:
-
Use of ipsilateral oblique angiographic views, which are crucial for accurately identifying the prostatic artery and its variants.
-
Positioning the microcatheter distally to ensure complete stasis during embolization. This distal position improves embolic delivery and reduces the likelihood of reflux or non‑target embolization.
-
Continuous, careful evaluation of angiograms throughout the embolization process, allowing operators to promptly identify and mitigate potential sources of non‑target flow.
-
Routine incorporation of cone beam CT, which was highly endorsed by the panel due to its superior ability to delineate pelvic vascular anatomy, confirm target vessel selection, and reduce the risk of complications.
Together, these technical steps form a consistent, evidence supported framework that enhances procedural success and minimizes risk across diverse practice settings.
How should operators approach preprocedural imaging, arterial access and embolic material selection when planning PAE?
Dr. Rostambeigi: Among the expert panelists, practices varied in regard to preprocedural imaging, from routinely obtaining MRI to using ultrasound as a minimum evaluation for prostate size.
However, there was unanimous agreement on several key principles:
-
Prostate cancer must be adequately evaluated prior to PAE, and if already diagnosed, its stage should be well understood before treatment proceeds.
-
Preprocedural imaging should clearly delineate prostate size and morphology.
-
Imaging can be helpful in evaluating major arterial disease.
Regarding arterial access, both radial and femoral access were considered acceptable approaches for PAE. However, recent findings from the MOSAIC study—highlighting a higher-than-expected incidence of silent brain infarcts associated with radial access—underscore the importance of careful patient selection. In these cases, minimizing the time required to cannulate the descending aorta, ideally to less than one minute, was emphasized as a key safety consideration in this recent study.
For embolic material selection, the panel reached agreement that both 300–500 μm and 100–300 μm particles are clinically effective, with no significant differences in major adverse events, while smaller particles may be associated with a higher rate of minor side effects.
What strategies are recommended to reduce the risk of nontarget embolization during PAE?
Dr. Rostambeigi: Our paper outlines a stepwise approach to minimizing the risk of nontarget embolization. Providers should carefully identify all potential sources of non‑target flow, both prior to embolization and continuously throughout the procedure. Vigilant angiographic evaluation is essential during each phase of the case.
Initial management can focus on the least invasive corrective measures, beginning with adjustments in pressure–flow dynamics. By reducing injection pressure and delivering embolic material slowly, operators can direct particles preferentially toward the target vasculature. If non‑target channels persist, the next recommended step is vasodilator administration, which can dilate the prostatic arterial lumen and diminish competitive flow from collaterals.
When necessary, the final step in the algorithm is coil embolization of identified non‑target branches. This should be performed judiciously and always with a thorough understanding of pelvic vascular anatomy to avoid compromising perfusion to critical territories such as the pudendal or rectal regions.
Any next steps or plans for follow‑up research?
Dr. Rostambeigi: There are several promising avenues for future research in PAE. For example, additional data is needed on patients with concomitant local prostate cancer. In addition, data are needed on older patient populations, who represent a substantial and growing demographic but remain relatively understudied in long-term analyses. Further investigation is also warranted into different embolic materials, including newer liquid embolics, as their safety profiles, durability and long‑term clinical impact require more evidence. Establishing and maintaining comprehensive patient registries will be essential to support these efforts and to generate high-quality, longitudinal data.
Beyond embolic materials, there is strong interest in evaluating techniques such as the coil‑out approach and the potential role of liquid embolics in reducing long‑term recurrence. Because PAE addresses a non‑life‑threatening condition in a population with often long life-expectancy, optimizing long‑term outcomes is particularly important.
Finally, advancements in AI‑guided embolization technologies represent an exciting frontier. These tools have the potential to enhance procedural planning, improve identification of target vessels, and support real‑time decision‑making during embolization. Assessing the impact of such technologies on safety, efficiency, and reproducibility will be an important area for future work as the field continues to evolve.