João Martins Pisco

Prostatic Arterial Supply: Anatomic and Imaging Findings Relevant for Selective Arterial Embolization

PURPOSE To describe the anatomy and imaging findings of the prostatic arteries (PAs) on multirow-detector pelvic computed tomographic (CT) angiography and digital subtraction angiography (DSA) before embolization for symptomatic benign prostatic hyperplasia (BPH). MATERIALS AND METHODS In a retrospective study from May 2010 to June 2011, 75 men (150 pelvic sides) underwent pelvic CT angiography and selective pelvic DSA before PA embolization for BPH. Each pelvic side was evaluated regarding the number of independent PAs and their origin, trajectory, termination, and anastomoses with adjacent arteries. RESULTS A total of 57% of pelvic sides (n = 86) had only one PA, and 43% (n = 64) had two independent PAs identified (mean PA diameter, 1.6 mm ± 0.3). PAs originated from the internal pudendal artery in 34.1% of pelvic sides (n = 73), from a common trunk with the superior vesical artery in 20.1% (n = 43), from the anterior common gluteal-pudendal trunk in 17.8% (n = 38), from the obturator artery in 12.6% (n = 27), and from a common trunk with rectal branches in 8.4% (n = 18). In 57% of pelvic sides (n = 86), anastomoses to adjacent arteries were documented. There were 30 pelvic sides (20%) with accessory pudendal arteries in close relationship with the PAs. No correlations were found between PA diameter and patient age, prostate volume, or prostate-specific antigen values on multivariate analysis with logistic regression. CONCLUSIONS PAs have highly variable origins between the left and right sides and between patients, and most frequently arise from the internal pudendal artery.

Prostatic Arterial Embolization for Benign Prostatic Hyperplasia: Short- and Intermediate-term Results

PURPOSE To evaluate the safety, morbidity, and short- and intermediate-term results of prostatic arterial embolization (PAE) for benign prostatic hyperplasia (BPH) after failure of medical treatment. MATERIALS AND METHODS This prospective study was approved by the institutional review board, and informed consent was obtained from all participants. Men older than 50 years with a diagnosis of BPH and moderate-to-severe lower urinary tract symptoms that were refractory to medical treatment for 6 months were eligible. PAE with nonspherical 80-180-μm (mean, 100-μm) and 180-300-μm (mean, 200-μm) polyvinyl alcohol particles was performed by means of a single femoral approach in most cases. Effectiveness variables of International Prostate Symptom Score (IPSS), quality of life (QOL) score, peak urinary flow, postvoid residual volume, International Index Erectile Function (IIEF) score, prostate volume, and prostate-specific antigen level were assessed for up to 24 months after the procedure. Statistical analysis included the Kaplan-Meier method and random-effects generalized least squares regression with autoregressive disturbance. RESULTS Eighty-nine consecutive patients (mean age, 74.1 years) were included. PAE was technically successful in 86 of the 89 patients (97%). Cumulative rates of clinical improvement in these patients were 78% in the 54 patients evaluated at 6 months and 76% in the 29 patients evaluated at 12 months. At 1-month follow-up, IPSS decreased by 10 points, QOL score decreased by 2 points, peak urinary flow increased by 38%, prostate volume decreased by 20%, postvoid residual volume decreased by 30 mL, and IIEF score increased by 0.5 point (all differences were significant at P < .01). These changes were sustained throughout the observation period. There was one major complication: Intraluminal necrotic tissue attached to the bladder, which was removed with simple surgery and did not necessitate wall reconstruction. CONCLUSION PAE is a safe and effective procedure, with low morbidity, no sexual dysfunction, and good short- and intermediate-term symptomatic control associated with prostate volume reduction.

Prostatic arterial supply: demonstration by multirow detector angio CT and catheter angiography.

ObjectivesTo evaluate the prostatic arterial supply with multidetector Angio CT and Digital Subtraction Angiography (DSA).MethodsDSA was performed in 21 male patients (7 of these also underwent Pelvic Angio CT); a further 4 patients only underwent Angio CT. Prostatic arteries were classified according to their origin, direction, number of pedicles, termination and anastomoses with surrounding arteries in 50 pelvic sides.ResultsThe most frequent origin was the internal pudendal artery (n = 28; 56%) with the common gluteal-pudendal trunk the next commonest (n = 14; 28%). Less frequent origins were the obturator artery (n = 6; 12%) or the inferior gluteal artery (n = 2; 4%). Two separate vascular pedicles were found in 12 pelvic sides (24%). There were anastomoses with the termination of the internal pudendal artery in 24% of cases (n = 12), with the contra-lateral prostatic arteries in 6 cases (12%), and to the superior vesical artery in 4 cases (8%).ConclusionsDefining prostatic artery origin and direction is paramount to allow selective catheterisation. Angio CT is very useful as a pre-intervention tool. The number of independent vascular pedicles and the presence of anastomoses with surrounding arteries should be taken into account when planning prostatic arterial embolisation.

Radiological Anatomy of Prostatic Arteries

One of the most challenging aspects of prostatic arterial embolization for patients with lower urinary tract symptoms and prostate enlargement or benign prostatic hyperplasia is identifying the prostatic arteries (PAs). With preprocedural computed tomography angiography it is possible to plan treatment and exclude patients when arterial anatomy is not suited, or when extensive atherosclerotic changes may affect technical success. There is an excellent correlation between the computed tomography angiography and digital subtraction angiography findings, enabling correct depiction of the male pelvic arterial anatomy (internal iliac branching patterns, relevant variants as accessory pudendal arteries, and PA anatomy). The prostate has a dual vascular arterial supply: a cranial or vesico-PA (named anterior-lateral prostatic pedicle) and a caudal PA (named posterior-lateral prostatic pedicle). These 2 prostatic pedicles may arise from the same artery in patients with only 1 PA (found in 60% of pelvic sides), or may arise independently in patients with 2 independent PAs (found in 40% of pelvic sides). The anterior-lateral prostatic pedicle vascularizes most of the central gland and benign prostatic hyperplasia nodules, frequently arises from the superior vesical artery in patients with 2 independent PAs, and is the preferred artery to embolize. The posterior-lateral prostatic pedicle has an inferior or distal origin, vascularizes most of the peripheral and caudal gland, and may have a close relationship with rectal or anal branches. In up to 60% of cases considerable anastomoses may be seen between the prostatic branches and surrounding arteries that should be taken into account when planning embolization. PAs lack pathognomonic digital subtraction angiography features; thus correct anatomical identification of the male pelvic and PAs is necessary to avoid untargeted ischemia to the bladder, rectum, anus, or corpus cavernosum.

Meta-Analysis of Prostatic Artery Embolization for Benign Prostatic Hyperplasia

PURPOSE To perform meta-analysis of available data on prostatic artery embolization (PAE). MATERIALS AND METHODS Meta-analysis was conducted on articles published between November 2009 and December 2015. Peer-reviewed studies with > 5 patients and standard deviations and/or individual-level data on one or more of the following outcomes were included: prostate volume (PV), peak flow rate (Qmax), postvoid residual (PVR), International Prostate Symptom Score (IPSS), quality of life (QOL) score, International Index of Erectile Function (IIEF) score, and prostate-specific antigen (PSA) level. A random-effects meta-analysis was performed on the outcomes at 1, 3, 6, and 12 months after PAE compared with baseline values, with a P < .05 decision rule as the null hypothesis rejection criterion. RESULTS Nineteen of 268 studies were included in data collection, with 6 included in the meta-analysis. At 12 months, PV decreased by 31.31 cm3 (P < .001), PSA remained unchanged (P = .248), PVR decreased by 85.54 mL (P < .001), Qmax increased by 5.39 mL/s (P < .001), IPSS improved by 20.39 points (P < .001), QOL score improved by -2.49 points (P < .001), and IIEF was unchanged (P = 1.0). There were a total of 218 adverse events (AEs) among 662 patients (32.93%), with 216 being Society of Interventional Radiology class A/B (99%). The most common complications were rectalgia/dysuria (n = 60; 9.0%) and acute urinary retention (n = 52; 7.8%). No class D/E complications were reported. CONCLUSIONS PAE provided improvement in Qmax, PVR, IPSS, and QOL endpoints at 12 months, with a low incidence of serious AEs (0.3%), although minor AEs were common (32.93%). There was no adverse effect on erectile function.

Medium- and Long-Term Outcome of Prostate Artery Embolization for Patients with Benign Prostatic Hyperplasia: Results in 630 Patients.

PURPOSE To confirm that prostatic artery embolization (PAE) has a positive medium- and long-term effect in symptomatic benign prostatic hyperplasia (BPH). MATERIALS AND METHODS Between March 2009 and October 2014, 630 consecutive patients with BPH and moderate-to-severe lower urinary tract symptoms refractory to medical therapy for at least 6 months or who refused any medical therapy underwent PAE. Outcome parameters were evaluated at baseline; 1, 3, and 6 months; every 6 months between 1 and 3 years; and yearly thereafter up to 6.5 years. RESULTS Mean patient age was 65.1 years ± 8.0 (range, 40-89 y). There were 12 (1.9%) technical failures. Bilateral PAE was performed in 572 (92.6%) patients and unilateral PAE was performed in 46 (7.4%) patients. The cumulative clinical success rates at medium- and long-term follow-up were 81.9% (95% confidence interval [CI], 78.3%-84.9%) and 76.3% (95% CI, 68.6%-82.4%). There was a statistically significant (P < .0001) change from baseline to last observed value in all clinical parameters: International Prostate Symptom Score (IPSS), quality-of-life (QOL), prostate volume, prostate-specific antigen, urinary maximal flow rate, postvoid residual, and International Index of Erectile Function. There were 2 major complications without sequelae. CONCLUSIONS PAE had a positive effect on IPSS, QOL, and all objective outcomes in symptomatic BPH. The medium- (1-3 y) and long-term (> 3-6.5 y) clinical success rates were 81.9% and 76.3%, with no urinary incontinence or sexual dysfunction reported.

Prostatic Artery Embolization to Treat Lower Urinary Tract Symptoms Related to Benign Prostatic Hyperplasia and Bleeding in Patients with Prostate Cancer: Proceedings from a Multidisciplinary Research Consensus Panel

AUR = acute urinary retention, BOO = bladder outlet obstruction, BPH = benign prostatic hyperplasia, FDA = U.S. Food and Drug Administration, IDE = investigational device exemption, IPSS = International Prostate Symptom Score, LUTS = lower urinary tract symptoms, PAE = prostatic artery embolization, PV = prostate volume, QOL = quality of life, TUMT = transurethral microwave thermotherapy, TURP = transurethral resection of the prostate, RCP = research consensus panel, UTI = urinary tract infection

How to Perform Prostatic Arterial Embolization

Prostatic arterial embolization (PAE) is an experimental alternative treatment for benign prostatic hyperplasia, with promising preliminary results. In comparison with surgery, its main advantages are the minimally invasive nature, outpatient setting, rapid recovery, and low morbidity. To avoid complications and to achieve technical success it is important to know the procedural technique in detail. In addition, for good clinical results, it is important to perform a bilateral and complete prostatic embolization. In this article, the different technical steps, including the initial site of puncture and the catheters and guidewires to be used, are described. Identification of the prostatic arteries is crucial. Correlation between computed tomography angiography and digital subtraction angiography helps to solve the difficulty of such identification. The skills for superselective catheterization of the prostatic arteries, the amounts of contrast injected, the preparation and size of the used particles and the end point of the procedure are also described.

Vasa vasorum changes following stent placement in experimental arterial stenoses.

PURPOSE Experimental stenoses were created in canine aortae to compare the effects of stent placement and balloon angioplasty on the vasa vasorum. MATERIALS AND METHODS A balloon-expandable Palmaz stent was placed in the proximal stenosis, and angioplasty was performed in the distal stenosis in each of eight dogs. Two dogs were killed at 4, 8, 12, and 18 months, respectively. Specimens were studied by means of microangiography, histology, scanning electronic microscopy, and Spalteholz technique. RESULTS At up to 12 months, there was proliferation of the vasa vasorum and a rich plexus formed in each of the animals at each treated site. More vasa vasorum were seen after stent placement than after angioplasty. The new vessels were mainly venules located in the media. At 18 months, there was regression of the venules and the vasa vasorum distribution returned to baseline. CONCLUSION The authors conclude that the effects of stents on the vasa vasorum are temporary.

Patient Selection and Counseling before Prostatic Arterial Embolization

Prostatic arterial embolization (PAE) for relief of lower urinary tract symptoms (LUTS) in patients with prostate enlargement or benign prostatic hyperplasia (PE or BPH) is an experimental procedure with promising preliminary results. Patient evaluation and selection before PAE is paramount to improve technical and clinical results. Our inclusion criteria for PAE include: male patients, age>40 years, prostate volume>30 cm(3) and diagnosis of PE or BPH with moderate to severe LUTS refractory to medical treatment for at least 6 months (International Prostate Symptom Score [IPSS]>18, or quality of life [QoL]>3, or both) or with acute urinary retention refractory to medical therapy. Exclusion criteria include: malignancy (based on pre-embolization digital rectal and transrectal ultrasound [TRUS] examinations and prostate specific antigen [PSA] measurements with positive biopsy), large bladder diverticula, large bladder stones, chronic renal failure, tortuosity and advanced atherosclerosis of a) iliac or b) prostatic arteries on pre-procedural computed tomographic angiography (CTA), active urinary tract infection and unregulated coagulation parameters. Approximately one-third of the patients seen initially on consultation satisfy the criteria to be selected for PAE after undergoing the pre-procedural patient evaluation workflow. In the pre-procedural consultation patients are informed of all possible therapeutic options for LUTS with the investigational nature of the procedure being strongly reinforced. The major advantage of PAE relies on the minimally-invasive nature of the technique with minimal morbidity and rapid recovery,and it being performed as an outpatient procedure. However, the experimental nature and uncertain clinical outcome should also be weighed before opting for PAE. All these considerations should be explained to the patient and discussed during the informed consent before PAE.