Advanced image guidance for prostatic artery embolization - a multicenter technical note

Benefits and advances of Cone Beam CT use in prostatic artery embolization: review of the literature and pictorial essay

Prostatic artery embolization (PAE) has proven to be an efficacious treatment for urinary symptoms of benign prostatic hyperplasia. PAE is performed in a complex and challenging anatomical field which may pose difficulties from procedural standpoint. Cone beam computed tomography (CBCT) has been proposed as an invaluable tool during the PAE procedure. A review of different techniques and advancements, as well as demonstration of CBCT benefits via a pictorial overview of the salient examples is lacking. The techniques of CBCT are discussed herein and the virtual injection technology as an advancement in CBCT is discussed. To show the merits of CBCT in PAE, a pictorial overview of various clinical scenarios is presented where CBCT can be crucial in decision making. These scenarios are aimed at showing different benefits including identification of the origin of the prostatic artery and avoiding non-target embolization. Other benefits may include ensuring complete embolization of entire prostate gland as angiographic appearance alone can be inconclusive if it mimics a severely thickened bladder wall or ensuring adequate embolization of the median lobe to provide relief from "ball-valve" effect. Further examples include verification of embolization of the entire prostate when rare variants or multiple (> 2) arterial feeders are present.

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.

Prostatic Artery Embolization Using Polyethylene Glycol Microspheres: A 1-Year Follow-up Prospective Study Including 30 Patients

PURPOSE

To evaluate safety and effectiveness of prostatic artery embolization (PAE) using polyethylene glycol (PEG) microspheres in patients with moderate-to-severe benign prostatic hyperplasia (BPH).

MATERIALS AND METHODS

A single-center, prospective study of 30 patients who underwent PAE from August 2020 to December 2021 using PEG 400-μm microspheres was conducted. Patient evaluation data using International Prostate Symptom Score (IPSS), quality of life (QoL) score, prostate-specific antigen (PSA), peak urinary flow rate (Qmax), postvoid residual volume (PVR), and prostate volume (PV) at baseline and 3 and 12 months after PAE were obtained.

RESULTS

Bilateral PAE was performed in all patients. One patient had early clinical failure (3.3%) and another presented with lower urinary tract symptoms (LUTSs) recurrence (3.3%) at the 12-month follow-up. Twenty-eight patients (93.3%) experienced significant and durable LUTS improvement. Mean absolute (and relative) improvement at 3 and 12 months were: IPSS, 14.6 points (-69%) for both; QoL, 3.3 points (-70%) and 3.5 points (-74%); Qmax, 6.3 mL/s (+78%) and 8.6 mL/s (+100%); PSA reduction, 1.2 ng/mL (-22%) and 1.0 ng/mL (-15%); PVR reduction, 48 mL (-56%) and 58.2 mL (-49%); PV reduction, 23.4 cm3 (-29%) and 19.6cm3 (-25%); (P < .05 for all). No major adverse events were observed. Minor adverse events included urinary tract infection (4/30, 13.3%), prostatic tissue elimination (3/30, 10%), penile punctiform ulcer (1/30, 3.3%), and urinary retention (1/30, 3.3%).

CONCLUSIONS

PAE using PEG microspheres was observed to be effective with sustained LUTS improvement at the 12-month follow-up. The incidence of urinary infection and prostatic tissue elimination was higher than previously reported for other embolics.

Controversies in Prostate Artery Embolization: Future Best Practice

Prevalence of lower urinary tract symptoms secondary to benign prostatic hyperplasia is correlated with age. Men seeking treatment options with a low side effect profile often turn to prostate artery embolization (PAE). PAE continues to be refined with advanced tools and optimized techniques. Nonetheless, there exist controversies in terms of best practices for the management of lower urinary track symptoms (LUTS) with PAE. These controversies are essential for medical progress. Herein we suggest best practices moving forward based on currently available data. Given extensive safety data, we recommend PAE be considered alongside medical management and as a precursor to surgery. Given demonstrated efficacy across gland sizes, PAE can be performed in a single session, ideally in a hybrid angio-CT suite, without preoperative cross-sectional imaging. PAE should be initially performed with 300- to 500-μm size particles, and instead consider exploring other particles and sizes for repeat PAE. Finally, PAE can also be considered as first-line option for recurrent disease given the efficacy and excellent safety profile. This article is not meant to purport a dogma, but rather to serve as a guide to the experienced practitioner in challenging his or her own biases when performing PAE.

Prostatic Artery Embolization: Technical Pearls

Benign prostatic hyperplasia (BPH) is a condition that primarily affects men between the fourth and seventh decades of life, occurring due to enlargement of the prostate which subsequently causes compression of the prostatic urethra causing chronic obstruction of the urinary outflow tract. BPH can cause significant quality-of-life issues such as urinary hesitancy, intermittency, decreased urinary stream, a sensation of incomplete emptying, dysuria, urinary retention, hematuria, and nocturia. Several medical and surgical treatment modalities are available for the treatment of lower urinary tract symptoms and other BPH-related sequela; however, increasingly prostate artery embolization is being utilized in this patient population. Technical demands for this procedure in this population can be significant. This article describes the optimal techniques, tricks, and advanced imaging techniques that can be used to achieve desired technical outcomes.

Prostate artery embolization on lower urinary tract symptoms related to benign prostatic hyperplasia: A systematic review and meta-analysis

BACKGROUND

Prostate artery embolization (PAE) is a promising minimally invasive therapy that improves lower urinary tract symptoms (LUTS) related to benign prostatic hyperplasia (BPH). Transurethral resection of the prostate (TURP) is the gold standard therapy for LUTS/BPH.

AIM

To evaluate the efficacy and safety of PAE vs TURP on LUTS related to BPH.

METHODS

A literature review was performed to identify all published articles on PAE vs TURP for LUTS/BPH. Sources included PubMed, Embase, Cochrane library databases, and Chinese databases before June 2022. A systematic review and meta-analysis were conducted. Outcome measurements were combined by calculating the mean difference with a 95% confidence interval. Statistical analysis was carried out using Review Manager 5.3.

RESULTS

Eleven studies involving 1070 participants were included. Compared with the TURP group, the PAE group had a similar effect on the International Index of Erectile Function (IPSS) score, Peak urinary flow rate (Qmax), postvoid residual volume (PVR), Prostate volume (PV), prostatic specific antigen (PSA), The International Index of Erectile Function short form (IIEF-5) scores, and erectile dysfunction during 24 mo follow-up. Lower quality of life (QoL) score, lower rate of retrograde ejaculation and shorter hospital stay in the PAE group. There was no participant death in either group. A higher proportion of haematuria, urinary incontinence and urinary stricture was identified in the TURP group.

CONCLUSION

PAE may be an appropriate option for elderly patients, patients who are not candidates for surgery, and patients who do not want to risk the potential adverse effects of TURP. Studies with large cases and long follow-up time are needed to validate results.

Single-Center Retrospective Comparative Study Evaluating the Benefit of Computed Tomography Angiography Prior to Prostatic Artery Embolization

PURPOSE

To explore whether a computed tomography angiography (CTA) of the pelvis prior to prostatic artery embolization (PAE) is a beneficial preprocedural planning tool regarding the technical success.

MATERIALS AND METHODS

Eighty patients with lower urinary tract symptoms treated with PAE were analyzed retrospectively. Forty of these patients received a CTA of the pelvis prior to the procedure (Group A) and were compared to 40 patients who were treated with PAE without prior CT imaging (Group B). Technical success rate, rate of complications, fluoroscopy time (FT), and mean dose area product (DAP) were assessed and compared. All operators performed at least 50 PAE prior to this study. When needed, cone-beam CT (CBCT) was available during intervention.

RESULTS

Mean age was 68.43 ± 8.30 years in Group A and 70.42 ± 7.11 years in Group B (p = 0.252). Mean body mass index was 26.78 ± 3.73 in Group A and 26.85 ± 3.5 in Group B (p = 0.319). Overall technical success was 96.3%. Bilateral PAE was achieved in 60 patients (75.0%) while unilateral PAE was performed in 17 patients (21.3%). Technical failure (no embolization) occurred in two patients of Group A and one patient of Group B. No statistical significance was seen between groups for technical success rate (p = 1.0). Mean DAP was 10,164 × cm² ± 3944 cGy × cm² in Group A and 10,039 × cm² ± 3761 cGy × cm² in Group B (p = 0.885). Mean FT was 49.27 ± 22.97 min in Group A and 44.32 ± 17.82 min in Group B (p = 0.285). No intervention-related complications during PAE were reported.

CONCLUSION

With experienced interventionalists and CBCT available during PAE, preprocedural CTA has no additional benefit for technical outcome.