Prostatic Arterial Embolization for Treatment of Lower Urinary Tract Symptoms Associated with Benign Prostatic Enlargement.

PURPOSE OF REVIEW: Prostatic artery embolization (PAE) is an emerging minimally invasive technique for lower urinary tract symptom reduction from benign prostatic hypertrophy (BPH). While the technique is becoming increasingly popular with patients and interventional radiologists, most urologists remain skeptical of the PAE's long-term efficacy and comparative success to the gold standard transurethral resection of the prostate. RECENT FINDINGS: PAE has been found in multiple meta-analyses to perform similarly to the gold standard transurethral resection of the prostate (TURP) with regard to patient-driven measures like IPSS and IPSS-QoL, while also performing favorably in objective measurements including Qmax and PVR out to at least 12 months post intervention. Furthermore, PAE has a demonstrated shorter hospital length of stay and fewer adverse events when compared to TURP. PAE provides patients with an alternative to transurethral options for the management of LUTS in the setting of bladder outlet obstruction. While long-term evidence demonstrating the durability of PAE is still forthcoming, the procedure has been demonstrated to be safe according to multiple meta-analyses. Patients deserve to be counseled on PAE as an alternative to surgery and made aware that while the overall treatment effect may not be as robust or durable, the procedure carries a favorable adverse event profile that is attractive to patients wishing to avoid a trans-urethral approach.

Assessing the Effects of Geniculate Artery Embolization in a Nonsurgical Animal Model of Osteoarthritis.

PURPOSE: To create a nonsurgical animal model of osteoarthritis (OA) to evaluate the effects of embolotherapy during geniculate artery embolization (GAE). MATERIALS AND METHODS: Fluoroscopy-guided injections of 700 mg of sodium monoiodoacetate were performed into the left stifle in 6 rams. Kinematic data were collected before and after induction. At 10 weeks after induction, Subjects 1 and 4-6 underwent magnetic resonance (MR) imaging with dynamic contrast enhancement (DCE) and Subjects 1, 3, and 4-6 underwent angiography with angiographic scoring to identify regions with greatest disease severity for superselective embolization (75-250-µm microspheres). Target vessel size was measured. At 24 weeks after angiography, DCE-MR imaging, angiography, and euthanasia were performed, and bilateral stifles were harvested. Medial/lateral tibial and femoral condylar, patellar, and synovial samples were cut, preserved, decalcified, and scored using the Osteoarthritis Research Society International criteria. The stifle and synovium Whole-Organ Magnetic Resonance Imaging Score and Multicenter Osteoarthritis Study score were determined. The volume transfer constant (Ktrans) and extracellular volume fraction (ve) were calculated from DCE-MR imaging along the lateral synovial regions of interest. RESULTS: The mean gross and microscopic pathological scores were elevated at 38 and 61, respectively. Mean synovitis score was elevated at 9.2. Mean pre-embolization and postembolization angiographic scores were 5 and 3.8, respectively. Mean superior, transverse, and inferior geniculate artery diameters were 3.1 mm ± 1.21, 2.0 mm ± 0.50, and 1.6 mm ± 0.41 mm, respectively. Mean pre-embolization and postembolization cartilage and synovitis scores were elevated at 35.13 and 73.3 and 5.5 and 9.2, respectively. The Ktrans/ve values of Subjects 4, 5, and 6 were elevated at 0.049/0.38, 0.074/0.53, and 0.065/0.51, respectively. Altered gait of the hind limb was observed in all subjects after induction, with reduced joint mobility. No skin necrosis or osteonecrosis was observed. CONCLUSIONS: A nonsurgical ovine animal knee OA model was created, which allowed the collection of angiographic, histopathological, MR imaging, and kinematic data to study the effects of GAE.

Improving Cone-Beam CT Angiography for Prostatic Artery Embolization: Is a Low-Dose Protocol Equivalent to the Standard?

PURPOSE: To compare the utility of low-dose versus standard cone-beam computed tomography (CT) angiography protocols in identifying nontarget embolization (NTE) during prostatic artery embolization (PAE). MATERIALS AND METHODS: A prospective, single-center, Phase-1 study (NCT02592473) was conducted for lower urinary tract symptoms in benign prostatic hyperplasia. Prostate volume, international prostate symptom score (IPSS), quality of life score (QoL), International Index of Erectile Function (IIEF), peak flow rate, UCLA Prostate Cancer Index (UCLA-PCI), and postvoid residual were recorded at baseline and 1, 3, 6, 12, and 24-months after PAE. Six-second (standard protocol, n = 29) or 5-second (low-dose protocol n = 45) rotations were made. Images were selected and matched in pairs by areas of NTE and compared by readers using a binomial generalized estimating equation model. Procedural outcomes were analyzed using a linear mixed model. RESULTS: Seventy-four cone-beam CT angiographies were performed in 21 patients. IPSS and QoL scores significantly improved (P <.05). There was no change in UCLA-PCI or IIEF scores. Dose area product of the low- and standard-dose protocol were 37,340.82 mGy·cm2 ± 104.66 and 62,645.66 mGy·cm2 ± 12,711.48, respectively, representing a dose reduction of 40.4%. A total of 120 comparisons showed no preference between the 2 protocols (P =.24). Observers identified 76 and 69 instances of NTE in the standard- and low-dose protocols, respectively (P =.125). CONCLUSIONS: Low-dose cone-beam CT angiography achieved equivalent clinical utility in identifying NTE during PAE, with the advantage of a lower radiation dose.

Decreased portal vein velocity is predictive of the development of portal vein thrombosis: A matched case-control study.

BACKGROUND & AIMS: Portal vein thrombosis (PVT) in cirrhosis may lead to hepatic decompensation and increased mortality. We aimed to investigate if decreased portal vein (PV) velocity is associated with future PVT. METHODS: Data on adult patients with cirrhosis and PVT between January 1, 2005 and July 30, 2015 were obtained. Cases with PVT were matched by age, gender and Model for End-stage Liver Disease (MELD) score to corresponding controls without PVT. Cox proportional hazards models, receiver operator curves and Kaplan Meier curves were constructed. RESULTS: One hundred subjects (50 matched pairs) with mean age 53.8±13.1 y and MELD score 14.9±5.5 were included in our analysis. Sixty-four percent were male and 76% were Child-Turcotte-Pugh Class A or B. Baseline characteristics (prior to development of PVT) were similar, except for baseline PV velocity (16.9 cm/s, 95% CI 13.9-20.0 PVT vs 25.0, 95% CI 21.8-28.8 no PVT, P<.001). 30 PVT subjects had PV velocity <15 cm/s compared to five without PVT (P<.001). On adjusted multivariable analysis, PV velocity was the strongest independent risk factor predicting PVT development (HR 0.86, 95% CI 0.80-0.93). The predictive value for PVT development was greatest for flow <15 cm/s (c-statistic 0.77). PV velocity <15 cm/s had a highly significant association with future PVT (HR 6.00, 95% CI 2.20-16.40, P=<.001). CONCLUSIONS: Decreased PV velocity is associated with increased risk of future PVT. Patients with cirrhosis and decreased PV velocity are a high-risk subgroup that warrants further investigation with prospective study.

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.

Transcaval Aortic Access for Percutaneous Thoracic Aortic Aneurysm Repair: Initial Human Experience.

Transcaval aortic access has been used for deployment of transcatheter aortic valves in patients in whom conventional arterial approaches are not feasible. The present report describes its use for thoracic endovascular aortic repair (TEVAR) in a 61-year-old man with a descending thoracic aneurysm. Transcaval access was performed in lieu of a surgical iliac conduit in view of small atherosclerotic pelvic arteries. TEVAR was successfully performed, followed by intervascular tract occlusion with the use of a ventricular septal occluder. Computed tomography 2 d later demonstrated no extravasation. At 1 mo, the aneurysm was free of endoleaks, the aortocaval tract had healed, and the patient had returned to baseline functional status.

Role for sphingosine kinase 1 in colon carcinogenesis.

Sphingosine kinase 1 (SphK1) phosphorylates sphingosine to form sphingosine-1-phosphate (S1P) and is a critical regulator of sphingolipid-mediated functions. Cell-based studies suggest a tumor-promoting function for the SphK1/S1P pathway. Also, our previous studies implicated the SphK1/S1P pathway in the induction of the arachidonic acid cascade, a major inflammatory pathway involved in colon carcinogenesis. Therefore, we investigated whether the SphK1/S1P pathway is necessary for mediating carcinogenesis in vivo. Here, we report that 89% (42/47) of human colon cancer samples stained positively for SphK1, whereas normal colon mucosa had negative or weak staining. Adenomas had higher expression of SphK1 vs. normal mucosa, and colon cancers with metastasis had higher expression of SphK1 than those without metastasis. In the azoxymethane (AOM) murine model of colon cancer, SphK1 and S1P were significantly elevated in colon cancer tissues compared to normal mucosa. Moreover, blood levels of S1P were higher in mice with colon cancers than in those without cancers. Notably, SphK1(-/-) mice subjected to AOM had significantly less aberrant crypt foci (ACF) formation and significantly reduced colon cancer development. These results are the first in vivo evidence that the SphK1/S1P pathway contributes to colon carcinogenesis and that inhibition of this pathway is a potential target for chemoprevention.

The rise and fall of arterial interventions: presentations at the Society of Interventional Radiology annual scientific meeting.

PURPOSE: To address hypotheses concerning a decline in presentations pertaining to vascular interventions by interventional radiologists and the loss of ground in other areas, such as oncology, of presentations in vascular interventions at the Society of Interventional Radiology (SIR) Annual Scientific Meeting. MATERIALS AND METHODS: All abstracts for scientific presentations and scientific exhibits from the program book of the SIR annual meeting were reviewed from the period 1996-2006. The abstracts were grouped in different classes, such as (a) type of methodology, (b) reports on arterial interventions, (c) reports on oncologic interventions, and (d) geographic origin. RESULTS: Scientific abstracts presented at the SIR annual meeting totaled 3,162. Presentations ranged from 177-407 (1996-2003) plus 250 in 2006 with a mean of 288 presentations per year. The overall number of abstracts reporting arterial interventions had a peak of 89 presentations in 2000 and declined to 34 presentations in 2006. Reports of arterial interventions from the United States had a peak of 48 presentations in 2003 and declined to 12 in 2006. Reports of arterial interventions from Europe had a peak of 37 presentations in 2000 and declined to 11 in 2006. Reports of arterial interventions from Asia had a peak of 10 presentations in 1999 and declined to 6 in 2006. The trends are similar for the three components of arterial interventions when analyzed individually. In 1997, 26.6% of all the presentations were arterial interventions; in 2000, 25.1%; and in 2006, only 13.6%. There was a trend in the increase of oncology presentations starting in 2004. In 2003, it was 10%, and it was 22.4% in 2006. CONCLUSIONS: There has been a decline in the overall number of abstracts presented at the SIR annual meeting after a peak in 2003. There has been a decline in the number of arterial intervention reports. The decline in presentations of arterial interventions that originated in the United States was also observed in presentations that originated from Europe and Asia. There has been an increasing trend in interventional oncology reports starting in 2004.

Successful recanalization of bile duct occlusion with a radiofrequency puncture wire technique.

A radiofrequency (RF) wire puncture technique was used in the recanalization of biliary anastomotic occlusions in five patients. The technical success of recanalization, which was defined as successful puncture and crossing of the obstruction followed by balloon cholangioplasty and internal-external biliary drainage without evidence of complications, was 100%. The average follow-up was 13 months (range, 11-16 months). For biliary occlusion recanalization, the RF wire may allow the use of percutaneous therapy in the treatment of a subset of individuals who would otherwise have to undergo open surgical intervention.

Inhibition of prostaglandin E(2) signaling through the EP(1) receptor does not affect prostacyclin production in human endothelial cells.

Accumulating evidence suggests that cyclooxygenase-2 (COX-2) and prostaglandin E(2) (PGE(2)) may play an important role in colon carcinogenesis. Thus, blockage of this pathway may be a suitable strategy for colon cancer chemoprevention. Recent clinical studies suggest that COX-2 inhibitors cause adverse cardiovascular effects due to prostacyclin (PGI(2)) inhibition. To test our hypothesis that inhibition of PGE(2) signaling through E-prostanoid (EP) receptors may offer a safer cardiovascular profile than COX-2 inhibition, we analyzed expression of 6-keto PGF(1alpha), a hydrated form of PGI(2) and PGI(2) synthase, which was stimulated with cytokines in human umbilical vein endothelial cells (HUVECs) treated with the EP(1) receptor antagonist ONO-8711 or the COX-2 inhibitor celecoxib. ONO-8711 did not inhibit both 6-keto PGF(1alpha) production and PGIS expression, whereas celecoxib did in HUVECs. ONO-8711 also inhibited cytokine-induced tissue factor expression in HUVECs. These results suggest that ONO-8711 may be a safer chemopreventive agent with respect to cardiovascular events.

Venous Compression Syndromes: a Review.

OPINION STATEMENT: Venous compression syndromes present a diagnostic and therapeutic challenge as the clinical presentation can be vague, diagnostic criteria are often not present, and high quality standardization of when and how to treat is not available in part due to the limited number of cases reported and also due to the limited literature available. Significant venous compression should be considered when clinical symptoms correlate to location of compression and there is evidence of hemodynamic changes including venous hypertension, collateral/variceal formation, and/or thrombus formation. In general, treatment of venous compression should address the etiology of the compression as opposed to just treating symptoms associated with it such as significant varices or anticoagulation for thrombus to avoid recurrence of symptoms.

Fluoroscopy-guided jejunal extension tube placement through existing gastrostomy tubes: analysis of 391 procedures.

PURPOSE: We aimed to evaluate the safety and efficacy of fluoroscopically placed jejunal extension tubes (J-arm) in patients with existing gastrostomy tubes. METHODS: We conducted a retrospective review of 391 J-arm placements performed in 174 patients. Indications for jejunal nutrition were aspiration risk (35%), pancreatitis (17%), gastroparesis (13%), gastric outlet obstruction (12%), and other (23%). Technical success, complications, malfunctions, and patency were assessed. Percutaneous gastrostomy (PEG) tube location, J-arm course, and fluoroscopy time were correlated with success/failure. Failure was defined as inability to exit the stomach. Procedure-related complications were defined as adverse events related to tube placement occurring within seven days. Tube malfunctions and aspiration events were recorded and assessed. RESULTS: Technical success was achieved in 91.9% (95% CI, 86.7%-95.2%) of new tubes versus 94.2% (95% CI, 86.7%-95.2%) of replacements (P = 0.373). Periprocedural complications occurred in three patients (0.8%). Malfunctions occurred in 197 patients (50%). Median tube patency was 103 days (95% CI, 71-134 days). No association was found between successful J-arm placement and gastric PEG tube position (P = 0.677), indication for jejunal nutrition (P = 0.349), J-arm trajectory in the stomach and incidence of malfunction (P = 0.365), risk of tube migration and PEG tube position (P = 0.173), or J-arm length (P = 0.987). A fluoroscopy time of 21.3 min was identified as a threshold for failure. Malfunctions occurred more often in tubes replaced after 90 days than in tubes replaced before 90 days (P < 0.001). A total of 42 aspiration events occurred (OR 6.4, P < 0.001, compared with nonmalfunctioning tubes). CONCLUSION: Fluoroscopy-guided J-arm placement is safe for patients requiring jejunal nutrition. Tubes indwelling for longer than 90 days have higher rates of malfunction and aspiration.