Influence of Interventionists' Experience on Radiation Exposure of Patients Who Underwent Prostate Artery Embolization: 4-Year Results from a Retrospective, Single-Center Study

Prostatic Artery Embolization: Lessons From 551 Procedures at a Single-Center

RATIONALE AND OBJECTIVES

This retrospective study evaluates the efficacy and safety of Prostatic Artery Embolization (PAE) for the treatment of benign prostatic hyperplasia (BPH) over five years at a single center, conducted by an experienced interventional radiologist.

MATERIALS AND METHODS

We analyzed 551 PAE interventions from January 2019 to July 2023. Key metrics included patient demographics, procedural details (radiation exposure, particle size), complication rates, pre- and post-interventional prostatic volume (PV), Prostate-specific Antigen (PSA) levels, International Prostate Symptom Score (IPSS), Quality of Life (QoL) scores and International Index of Erectile Function (IIEF) scores. We assessed data normality, performed group and paired sample comparisons, and evaluated correlations.

RESULTS

For 551 men, the average patient age was 68.81 ± 8.61 years undergoing bilateral embolization. The particle size predominantly used was 100-300 µm (n = 441). PAE lead to significant (p < .001) reduction of both PV (-9.67 ± 14.52 mL) and PSA level (-2,65 ± 1.56 ng/mL) between pre- and three months after PAE. Substantial improvement were observed for IPSS (-9 points) and QoL scores (-2 points), with stable IIEF scores. Only minor complications (n = 16) were reported, and no major complications were observed. Between the first PAE in 2019 and the routinely performed PAE in 2023 significant (p < .0001) reductions in fluoroscopy (-25.2%), and procedural times (-26.1%) were observed.

CONCLUSION

In conclusion, PAE is a safe and effective treatment for BPH, offering significant improvements in lower urinary tract symptoms (LUTS) and QoL while maintaining sexual function.

Value of magnetic resonance angiography before prostatic artery embolization for intervention planning

Knowledge about anatomical details seems to facilitate the procedure and planning of prostatic artery embolization (PAE) in patients with symptomatic benign prostatic hyperplasia (BPS). The aim of our study was the pre-interventional visualization of the prostatic artery (PA) with MRA and the correlation of iliac elongation and bifurcation angles with technical success of PAE and technical parameters. MRA data of patients with PAE were analysed retrospectively regarding PA visibility, PA type, vessel elongation, and defined angles were correlated with intervention time, fluoroscopy time, dose area product (DAP), cumulative air kerma (CAK), contrast media (CM) dose and technical success of embolization. T-test, ANOVA, Pearson correlation, and Kruskal-Wallis test was applied for statistical analysis. Between April 2018 and March 2021, a total of 78 patients were included. MRA identified the PA origin in 126 of 147 cases (accuracy 86%). Vessel elongation affected time for catheterization of right PA (p = 0.02), fluoroscopy time (p = 0.05), and CM dose (p = 0.02) significantly. Moderate correlation was observed for iliac bifurcation angles with DAP (r = 0.30 left; r = 0.34 right; p = 0.01) and CAK (r = 0.32 left; r = 0.36 right; p = 0.01) on both sides. Comparing the first half and second half of patients, median intervention time (125 vs. 105 min.) and number of iliac CBCT could be reduced (p < 0.001). We conclude that MRA could depict exact pelvic artery configuration, identify PA origin, and might obviate iliac CBCT. Vessel elongation of pelvic arteries increased intervention time and contrast media dose while the PA origin had no significant influence on intervention time and/or technical success.

PAE planning: Radiation exposure and image quality of CT and CBCT

PURPOSE

To determine accurate organ doses, effective doses, and image quality of computed tomography (CT) compared with cone beam CT (CBCT) for correct identification of prostatic arteries.

METHOD

A dual-energy CT scanner and a flat-panel angiography system were used. Dose measurements (gallbladder (g), intestine (i), bladder (b), prostate (p), testes (t), active bone marrow of pelvis (bmp) and femura (bmf)) were performed using an anthropomorphic phantom with 65 thermoluminescent dosimeters in the pelvis and abdomen region. For the calculation of the contrast-to-noise ratio (CNR) of the pelvic arteries, a patient whose weight and height were almost identical to those of the phantom was selected for each examination type.

RESULTS

The effective dose of CT was 2.7 mSv and that of CBCT was 21.8 mSv. Phantom organ doses were lower for CT than for CBCT in all organs except the testes (g: 1.2 mGy vs. 3.3 mGy, i: 5.8 mGy vs. 23.9 mGy, b: 6.9 mGy vs. 19.4 mGy, p: 6.4 mGy vs. 13.2 mGy, t: 4.7 mGy vs. 2.4 mGy, bmp: 5.1 mGy vs. 18.2 mGy, bmf: 3.3 mGy vs. 6.6 mGy). For human pelvic arteries, the CNR of CT was better than that of CBCT, with the exception of one prostate artery that showed stenosis on CT. Evaluation by experienced radiologists also confirmed the better detectability of prostate arteries on CT examination.

CONCLUSIONS

In our study preprocedural CT had lower organ doses and better image quality comparedd with CBCT and should be considered for the correct identification of prostatic arteries.

Multicenter Quantification of Radiation Exposure and Associated Risks for Prostatic Artery Embolization in 1476 Patients

Background Prostatic artery embolization (PAE) is a safe, minimally invasive angiographic procedure that effectively treats benign prostatic hyperplasia; however, PAE-related patient radiation exposure and associated risks are not completely understood. Purpose To quantify radiation dose and assess radiation-related adverse events in patients who underwent PAE at multiple centers. Materials and Methods This retrospective study included patients undergoing PAE for any indication performed by experienced operators at 10 high-volume international centers from January 2014 to May 2021. Patient characteristics, procedural and radiation dose data, and radiation-related adverse events were collected. Procedural radiation effective doses were calculated by multiplying kerma-area product values by an established conversion factor for abdominopelvic fluoroscopy-guided procedures. Relationships between cumulative air kerma (CAK) or effective dose and patient body mass index (BMI), fluoroscopy time, or radiation field area were assessed with linear regression. Differences in radiation dose stemming from radiopaque prostheses or fluoroscopy unit type were assessed using two-sample t tests and Wilcoxon rank sum tests. Results A total of 1476 patients (mean age, 69.9 years ± 9.0 [SD]) were included, of whom 1345 (91.1%) and 131 (8.9%) underwent the procedure with fixed interventional or mobile fluoroscopy units, respectively. Median procedure effective dose was 17.8 mSv for fixed interventional units and 12.3 mSv for mobile units. CAK and effective dose both correlated positively with BMI (R2 = 0.15 and 0.17; P < .001) and fluoroscopy time (R2 = 0.16 and 0.08; P < .001). No radiation-related 90-day adverse events were reported. Patients with radiopaque implants versus those without implants had higher median CAK (1452 mGy [range, 900-2685 mGy] vs 1177 mGy [range, 700-1959 mGy], respectively; P = .01). Median effective dose was lower for mobile than for fixed interventional systems (12.3 mSv [range, 8.5-22.0 mSv] vs 20.4 mSv [range, 13.8-30.6 mSv], respectively; P < .001). Conclusion Patients who underwent PAE performed with fixed interventional or mobile fluoroscopy units were exposed to a median effective radiation dose of 17.8 mSv or 12.3 mSv, respectively. No radiation-related adverse events at 90 days were reported. © RSNA, 2024 See also the editorial by Mahesh in this issue.

Virtual Injection Software Reduces Radiation Exposure and Procedural Time of Prostatic Artery Embolization Performed with Cone-Beam CT

PURPOSE

To evaluate the impact of virtual injection software (VIS) use during cone-beam computed tomography (CT)-guided prostatic artery embolization (PAE) on both patient radiation exposure and procedural time.

MATERIALS AND METHODS

This institutional review board (IRB)-approved comparative retrospective study analyzed the treatment at a single institution of 131 consecutive patients from January 2020 to May 2022. Cone-beam CT was used with (Group 1, 77/131; 58.8%) or without VIS (Group 2, 54/131, 41.2%). Radiation exposure (number of digital subtraction angiography [DSA] procedures), dose area product (DAP), total air kerma (AK), peak skin dose (PSD), fluoroscopy time (FT), and procedure time (PT) were recorded. The influences of age, body mass index, radial access, and use of VIS were assessed.

RESULTS

In bivariate analysis, VIS use (Group 1) showed reduction in the number of DSA procedures (8.6 ± 3.7 vs 16.8 ± 4.3; P < .001), DAP (110.4 Gy·cm2 ± 46.8 vs 140.5 Gy·cm2 ± 61; P < .01), AK (642 mGy ± 451 vs 1,150 mGy ± 637; P = .01), PSD (358 mGy ± 251 vs 860 mGy ± 510; P = .001), FT (35.6 minutes ± 15.4 vs 46.6 minutes ± 20; P = .001), and PT (94.6 minutes ± 41.3 vs 115.2 minutes ± 39.6, P = .005) compared to those in Group 2. In multivariate analysis, AK, PSD, FT, and PT reductions were associated with VIS use (P < .001, P < .001, P = .001, and P = .006, respectively).

CONCLUSIONS

The use of VIS during PAE performed under cone-beam CT guidance led to significant reduction in patient radiation exposure and procedural time.

Radiation Exposure during Prostatic Artery Embolization: A Single Institution Review

ABSTRACT

Prostate artery embolization is a minimally invasive treatment for benign prostatic hyperplasia, and imaging is indispensable for the technical success of this procedure; however, imaging is a major source of radiation exposure for patients and healthcare providers. Radiation emission during prostate artery embolization procedures at a single institution was evaluated to determine radiation exposure with the goal to work toward minimizing exposure. All patients at a single institution that underwent outpatient unilateral/bilateral prostate artery embolization between 4 January 2019 and 16 November 2021 were retrospectively evaluated; data collected included body mass index, prostate volume, and indications for prostate artery embolization. Technical parameters recorded were air kerma, procedure time, fluoroscopy time, number of acquisitions, and intra-procedural imaging modalities. Fisher's t-test, ANOVA, and chi-square analyses were used as appropriate for statistical analysis (P < 0.05). Overall, 56 patients were included in the study. Body mass index (obesity; P = 0.0017) was a significant predictor of increased air kerma; prostate size and bilateral vs. unilateral prostate artery embolization were not significantly associated with increased air kerma despite the number of acquisitions being significantly different between bilateral and unilateral embolization (P = 0.0064). When evaluating radiation exposure during prostate artery embolization, increased body mass index significantly predicted increased air kerma. Contrary to the literature, the extent of embolization (bilateral vs. unilateral) was not associated with increased air kerma regardless of higher acquisitions and procedure time associated with bilateral prostate artery embolization. Increased radiation protection efforts should be considered for patients with higher body mass index to protect patients and practitioners.Health Phys. 124(0):000-000; 2023.

Center experience and other determinants of patient radiation exposure during prostatic artery embolization: a retrospective study in three Scandinavian centers

OBJECTIVES

To evaluate the effects of center experience and a variety of patient- and procedure-related factors on patient radiation exposure during prostatic artery embolization (PAE) in three Scandinavian centers with different PAE protocols and levels of experience. Understanding factors that influence radiation exposure is crucial in effective patient selection and procedural planning.

METHODS

Data were collected retrospectively for 352 consecutive PAE procedures from January 2015 to June 2020 at the three centers. Dose area product (DAP (Gy·cm²)) was selected as the primary outcome measure of radiation exposure. Multiple patient- and procedure-related explanatory variables were collected and correlated with the outcome variable. A multiple linear regression model was built to determine significant predictors of increased or decreased radiation exposure as reflected by DAP.

RESULTS

There was considerable variation in DAP between the centers. Intended unilateral PAE (p = 0.03) and each 10 additional patients treated (p = 0.02) were significant predictors of decreased DAP. Conversely, increased patient body mass index (BMI, p < 0.001), fluoroscopy time (p < 0.001), and number of digital subtraction angiography (DSA) acquisitions (p < 0.001) were significant predictors of increased DAP.

CONCLUSIONS

To minimize patient radiation exposure during PAE radiologists may, in collaboration with clinicians, consider unilateral embolization, pre-interventional CTA for procedure planning, using predominantly anteroposterior (AP) projections, and limiting the use of cone-beam CT (CBCT) and fluoroscopy.

KEY POINTS

• Growing center experience and intended unilateral embolization decrease patient radiation exposure during prostatic artery embolization. • Patient BMI, fluoroscopy time, and number of DSA acquisitions are associated with increased DAP during procedures. • Large variation in radiation exposure between the centers may reflect the use of CTA before and CBCT during the procedure.

Prostatic Artery Embolization: Indications, Preparation, Techniques, Imaging Evaluation, Reporting, and Complications

Benign prostatic hyperplasia (BPH) is a noncancerous growth of the transitional zone of the prostate, which surrounds the prostatic urethra. Consequently, it can cause lower urinary tract symptoms (LUTS) and bladder outlet obstruction symptoms that may substantially reduce a patient's quality of life. Several treatments are available for BPH, including medications such as α-blockers and 5α-reductase inhibitors and surgical options including transurethral resection of the prostate and prostatectomy. Recently, prostatic artery embolization (PAE) has emerged as a minimally invasive treatment option for selected men with BPH and moderate to severe LUTS. Adequate pre- and postprocedural evaluations with clinical examinations and questionnaires, laboratory tests, and urodynamic and imaging examinations (particularly US, MRI, and CT) are of key importance to achieve successful treatment. Considering that the use of PAE has been increasing in tertiary hospital facilities, radiologists and interventional radiologists should be aware of the main technical concepts of PAE and the key features to address in imaging reports in pre- and postprocedural settings. An invited commentary by Lopera is available online. Online supplemental material is available for this article. ^©RSNA, 2021.

Prostatic Artery Embolization: Influence of Cone-Beam Computed Tomography on Radiation Exposure, Procedure Time, and Contrast Media Use

Purpose

To evaluate the effect of cone-beam computed tomography (CBCT) on radiation exposure, procedure time, and contrast media (CM) use in prostatic artery embolization (PAE).

Materials and Methods

Seventy-eight patients were enrolled in this retrospective, single-center study. All patients received PAE without (group A; n = 39) or with (group B; n = 39) CBCT. Total dose-area product (DAP_total; Gycm²), total entrance skin dose (ESD_total; mGy), and total effective dose (ED_total; mSv) were primary outcomes. Number of digital subtraction angiography (DSA) series, CM use, fluoroscopy time, and procedure time were secondary outcomes. PAE in group A was performed by a single radiologist with 15 years experience, PAE in group B was conducted by four radiologists with 4 to 6 years experience.

Results

For groups A vs. B, respectively, median (IQR): DAP_total 236.94 (186.7) vs. 281.20 (214.47) Gycm²(p = 0.345); ED_total 25.82 (20.35) vs. 39.84 (23.75) mSv (p =  < 0.001); ESD_total 2833 (2278) vs. 2563 (3040) mGy(p = 0.818); number of DSA series 25 (15) vs. 23 (10)(p = 0.164); CM use 65 (30) vs. 114 (40) mL(p =  < 0.001); fluoroscopy time 23 (20) vs. 28 (25) min(p = 0.265), and procedure time 70 (40) vs.120 (40) min(p =  < 0.001). Bilateral PAE was achieved in 33/39 (84.6%) group A and 32/39 (82.05%) group B(p = 0.761), all other patients received unilateral PAE. There were no significant differences between clinical parameters and origins of the prostatic arteries (PA) (p = 0.206–1.00).

Conclusion

Operators with extensive expertise on PAE may not benefit from addition of CBCT to DSA runs, whereas for operators with less expertise, CBCT when used alongside with DSA runs increased the overall radiation exposure.

Efficacy and safety of prostatic artery embolization for benign prostatic hyperplasia: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To investigate the efficacy and safety of prostatic artery embolization (PAE) vs. transurethral resection of the prostate (TURP) in patients affected by benign prostatic hyperplasia (BPH). We also reviewed mean changes from baseline in PAE at selected follow-up points.

METHODS

PubMed, Web of Science, and Embase were searched up to May 1, 2020. Randomized controlled trials on PAE were collected according to specific inclusion and exclusion criteria. Meta-analyses were performed using RevMan 5.3, STATA 14, and GraphPad Prism 8. Pooled patient-reported scores and functional outcomes were calculated by using a fixed or random-effect model.

RESULTS

Eleven articles met our selection criteria and ten independent patient series were included in the final analysis. Pooled estimates suggested no significant difference between TURP and PAE for patient-reported outcomes including International Prostate Symptom Score (2.32 (- 0.44 to 5.09)) and quality of life (0.18 (- 0.41 to 0.77)) at 12 months. PAE was less effective regarding improvements in most functional outcomes such as maximum flow rate, prostate volume, and prostate-specific antigen. Moreover, PAE may be associated with relatively fewer complications, lower cost, and shorter hospitalization. After the PAE procedure, the overall weighted mean differences for all outcomes except sexual health scores were significantly improved from baseline during follow-up to 24 months.

CONCLUSION

PAE is non-inferior to TURP with regard to improving patient-reported outcomes, though most functional parameters undergo more changes after TURP than after PAE. Moreover, PAE can significantly continue to relieve symptoms for 24 months without causing serious complications.

KEY POINTS

• PAE is as effective as TURP in improving subjective symptom scores, with fewer complications and shorter hospitalization times. • PAE is inferior to TURP in the improvement of most functional outcomes. • Improvements due to PAE are durable during follow-up to 24 months.