Bronchial artery embolization using small particles is safe and effective: a single center 12-year experience.

BACKGROUND: Bronchial artery embolization (BAE) using particles is an established treatment for hemoptysis. The use of polyvinyl alcohol (PVA) with a particle size of 300 µm or larger is thought to reduce the risk of non-target embolization but may result in more proximal vessel occlusion than is ideal, resulting in a high rate of early recurrent hemorrhage. OBJECTIVE: This study evaluates the safety and efficacy of BAE using PVA particles with a size of less than 300 µm. METHODS: All patients who underwent BAE between 2010 and 2022 at a tertiary center were included. Demographic data, etiology and volume of hemoptysis, technical and clinical success, procedure-related complications, and follow-up information were collected from patients' electronic records. 150-250 µm PVA particles were used to commence embolization in all patients with the subsequent use of larger-sized particles in some individuals. The Kaplan-Meier method was used to estimate recurrence and survival rates. RESULTS: One hundred forty-four patients underwent 189 embolization procedures between 2010 and 2022 and were followed up for a median of 35 months [IQR 19-89]. 150 µm to 250 µm PVA particles were used as the sole embolic agent in 137 cases. Hemoptysis recurred within 30 days in 7%. The median time to repeat intervention was 144 days [IQR 42-441]. Seventeen out of 144 patients had a pulmonary artery branch pseudoaneurysm. The rate of major complications was 1% with no instances of stroke or spinal artery ischemia. Thirty-day mortality was 2% (4/189). CONCLUSION: BAE using 150-250 µm PVA particles is safe and effective with few complications and low rates of early hemoptysis recurrence. CLINICAL RELEVANCE STATEMENT: BAE using small particles is likely to improve outcomes, particularly the rate of early recurrence, in patients with hemoptysis, without an increase in procedural complications. KEY POINTS: BAE is a safe and effective treatment for patients with hemoptysis. Using small PVA particles in BAE has few complications and low rates of early recurrence. Pulmonary artery pseudoaneurysms should be actively sought in those with hemoptysis undergoing BAE.

Pulmonary arteriovenous malformations in Rendu-Osler-Weber syndrome.

Rendu-Osler-Weber syndrome, also known as hereditary hemorrhagic telangiectasia, is an autosomal dominant hereditary disorder. It is characterized by presence of multiple arteriovenous malformations (AVMs) and telangiectasias. This article reports two cases of patients with Rendu-Osler-Weber syndrome who had pulmonary AVMs and underwent successful endovascular treatment. A brief review of the literature shows that up to 50% of patients with the syndrome have pulmonary AVMs and there is usually a positive family history in these patients. These pulmonary AVMs are multiple in 30% of cases and are associated with the most severe disease complications. Most patients are asymptomatic, even in the presence of AVMs with right-left shunts. When these shunts exceed 25% of the total blood volume, dyspnea, cyanosis, digital clubbing, and extracardiac murmurs may occur. Endovascular treatment is safe and offers control of complications from hereditary hemorrhagic telangiectasia and is currently the treatment of choice for these lesions.

Catheter-directed hemorrhoidal embolization for rectal bleeding due to hemorrhoids (Goligher grade I-III): prospective outcomes from a Spanish emborrhoid registry.

OBJECTIVES: To evaluate the safety and efficacy of catheter-directed hemorrhoidal embolization (CDHE) by microcoil embolization for rectal bleeding due to hemorrhoids classified as Goligher grade I-III. METHODS: Eighty patients (62.5% males) with a mean age of 48 ± 9 years were recruited prospectively. All patients had symptomatic bleeding hemorrhoids. All patients were classified according to Goligher classification: grade I (13.7%), grade II (71.1%), grade III (15%), and no grade IV were recruited in this study. In all cases, microcoils were used to embolize the superior rectal artery(SRA), and microspheres if recurrence of bleeding occurred. Follow-up evaluation (1, 3, 6, and 12 months) included clinical examination and anoscopy. A questionnaire was conducted to determine improvement regarding bleeding, quality of life before, and the degree of patient satisfaction of each participant. RESULTS: Technical success was achieved in 100% of the cases. Fifty-five (68.7%) participants had the absence of rectal bleeding after 12 months of embolization. VAS and QL improved 4 points and 1.5 respectively after embolization. A total of 25/80 (31.3%) had a recurrence in rectal bleeding. Seventeen (21.3%) patients underwent a second embolization, and four patients (5%) were treated with open hemorrhoidectomy. No major complications were observed. Sixteen participants had minor complications. Subjective post-treatment symptom and QL surveys showed significant differences from the baseline survey. Likewise, the degree of satisfaction in the telephone survey at 12 months revealed a high degree of patient satisfaction (8.3±1.1). CONCLUSIONS: The present study demonstrates that CDHE is a feasible, well-tolerated, ambulatory, anal sphincter-sparing procedure for the treatment of internal hemorrhoids. CLINICAL RELEVANCE STATEMENT: CDHE is a simple procedure, well tolerated and accepted by patients, that preserves the anal sphincter and presents few complications when metal devices or microspheres are used as embolic agents. KEY POINTS: • The technical success rate of CDHE, defined as the closure of all the SRA in their distal segment, was achieved 100% of all patients. However, a second embolization treatment was required since 21.25% of the patients experienced rectal bleeding. • Overall, CDHE's safety profile is acceptable. After the procedure and 1 year of follow-up, no significant complications were observed. • Encouraging clinical outcomes have demonstrated CDHE in individuals with hemorrhoids and mild prolapse Goligher grades I-III with persistent rectal bleeding.

Upper Gastrointestinal Bleeding Due to a Left Gastric Artery Pseudoaneurysm: A Case Series.

BACKGROUND: Left gastric artery (LGA) pseudoaneurysm presenting with upper gastrointestinal (UGI) bleeding is rare but fatal, unless treated. AIMS: We aimed to describe the clinical and endoscopic features of patients with UGI bleeding due to LGA pseudoaneurysms. METHODS: We performed a computerized search of our hospital's de-identified clinical data warehouse to identify patients with UGI bleeding due to an LGA pseudoaneurysm between 2000 and 2020. Patients' electronic medical records and data on esophagogastroduodenoscopy and digital subtraction angiography were reviewed retrospectively. RESULTS: Of 26 patients with an LGA pseudoaneurysm, six patients had UGI bleeding related to an LGA pseudoaneurysm. No patients had previous vascular diseases or pancreatitis. One patient had liver cirrhosis and a history of radiofrequency ablation for hepatocellular carcinoma, one had colon cancer, two had undergone abdominal surgeries, one had received chemoradiotherapy for renal cell carcinoma, and one had no intraabdominal diseases. Symptoms were hematemesis in two, hematochezia in the other two, and melena in the remaining two patients. Esophagogastroduodenoscopy showed a pulsating bulge in the ulcer in two and a large Dieulafoy's lesion-like structure in four patients. All patients achieved hemostasis by angioembolization. CONCLUSION: LGA pseudoaneurysm should be suspected in UGI bleeding if a large Dieulafoy's lesion-like structure or a pulsating bulge in the ulcer is found at the lesser curvature of the gastric body on endoscopy and if the patient has any intra-abdominal inflammatory disease.

Novel use of precipitating hydrophobic injectable liquid (PHIL) in pre-operative angioembolisation of a large posterior auricular arteriovenous malformation.

BACKGROUND: Large arteriovenous malformations are often managed via endovascular embolisation followed by surgical resection. We describe the use of a new liquid embolic agent (LEA) - precipitating hydrophobic injectable liquid (PHIL) and its advantages over existing LEAs. CASE: A 60-year-old male presented with a progressively enlarging right post-auricular arteriovenous malformation. He underwent successive angioembolisation with PHIL and subsequent surgical resection on post-embolisation day 1. CONCLUSION: To our knowledge, this is the first reported case of PHIL being used in pre-operative embolization of a large extra-cranial head and neck AVM. Its excellent penetration into small calibre vessels, decreased glare artefact on imaging and decreased skin pigmentation render it a compelling alternative to existing LEAs.

The essential role of thoracic duct embolization in management of traumatic iatrogenic chylothorax.

This study aims to describe a case series of patients who underwent thoracic duct embolization (TDE) to treat traumatic iatrogenic chylothorax (TIC). Three patients were included: Case #1, a 49-year-old woman with follicular lymphoma developed a TIC following video-assisted thoracoscopic surgery to resect a solid right paravertebral mass and was treated with TDE using microcoils and N-butyl cyanoacrylate (NBCA) glue. Case #2, a 68-year-old man with cardiac amyloidosis developed a TIC following heart transplantation and was treated with TDE using microcoils and ethylene vinyl alcohol copolymer. Case#3: A 6-year-old patient with congenital heart disease developed a TIC following a Fontan procedure and was treated with TDE using NBCA glue. All lesions were identified during lymphangiography and TDE was successfully performed in all cases. TDE is a safe and valuable technique that provides minimally invasive treatment for TCI.

Este estudo objetiva descrever uma série de casos de pacientes submetidos a embolização do ducto torácico (EDT) para tratamento de quilotórax iatrogênico (QI). Três pacientes foram incluídos. Caso 1: um homem de 49 anos com linfoma folicular apresentou QI após ressecção de uma massa paravertebral por toracoscopia vídeo-assistida e foi submetido a EDT com micromolas e n-butil-cianoacrilato (NBCA). Caso 2: um homem de 68 anos com amiloidose cardíaca apresentou QI após ser submetido a transplante cardíaco e foi submetido a EDT com micromolas e copolímero de etileno e álcool vinílico. Caso 3: um paciente de 6 anos com malformação cardíaca congênita apresentou QI após cirurgia de Fontan e foi submetido a EDT com NBCA. Todas as lesões foram identificadas durante a linfangiografia, e a EDT foi realizada com sucesso. A EDT é uma técnica segura e valiosa, que pode oferecer um tratamento minimamente invasivo em casos de QI.

Utility and Outcome of Angioembolization for High-Grade Renal Trauma Management in a Large Hospital-Based Trauma Registry.

PURPOSE: We evaluated angioembolization (AE) use for high-grade renal trauma (HGRT) management and compared AE vs surgical repair (SR) in requiring nephrectomy. MATERIALS AND METHODS: Using National Trauma Data Bank® 2013-2018, we identified patients with HGRT who underwent AE or SR as initial management. Therapy failure was defined as performing subsequent nephrectomy, partial nephrectomy, SR or AE. Logistic regression was performed to assess the association between intervention type (AE vs SR) and nephrectomy. Analysis was repeated in a propensity score-matched cohort constructed by matching AE to SR patients on American Association for the Surgery of Trauma (AAST) grade, injury mechanism (blunt vs penetrating) and hemodynamic instability (systolic blood pressure <90 mmHg). RESULTS: There were 266 patients in the AE group and 215 in the SR group. Median age was 29.5 years and 212 patients (44.1%) had penetrating injuries. AE was successful in 94.2% and 85.3% of grade IV and V injuries, respectively, whereas SR was successful in 82.1% and 56%, respectively. Grade V injury was associated with AE failure in the adjusted analysis (OR 3.55, 95% CI 1.22-10.2, p=0.02). Nephrectomy was less likely to be performed after AE vs after SR in HGRT (6.4% vs 17.2%, p=0.01), AAST grade IV (4.2% vs 13.7%, p=0.001) and AAST grade V (12% vs 44%, p=0.001). The matched cohort comprised 528 patients. In post-match regression, AE, compared to SR, was associated with lower odds of nephrectomy (OR 0.18, 95% CI 0.04-0.70, p=0.013). CONCLUSIONS: AE achieved superior kidney salvage compared to SR in this observational cohort. These results inform both clinical practice and future prospective trials.

Thoracic duct embolization in treating postoperative chylothorax: does bail-out retrograde access improve outcomes?

OBJECTIVES: To evaluate clinical outcomes of thoracic duct embolization (TDE) for the management of postoperative chylothorax with the aid of the bail-out retrograde approach for thoracic duct cannulation (TDC). MATERIALS AND METHODS: Forty-five patients with postoperative chylothorax underwent Lipiodol lymphangiography (LLG) between February 2016 and November 2019. If targetable central lymphatic vessels were identified in LLG, TDC, a prerequisite for TDE, was attempted. While the conventional antegrade transabdominal approach was the standard TDC method, the retrograde approach was applied as a bail-out method. Embolization, the last step of TDE, was performed after confirming leakages in the trans-TDC catheter lymphangiography. Technical and clinical success rates were determined retrospectively. RESULTS: TDC was attempted in 40 among 45 patients based on LLG findings. The technical success rate of TDC with the conventional antegrade approach was 78% (31/40). In addition, six more patients were cannulated using the bail-out retrograde approach, which raised the technical success rate to 93% (37/40). While 35 patients underwent embolization (TDE group), ten patients did not (non-TDE group) for the following reasons: (1) lack of targetable lymphatics for TDC in LLG (n = 5), (2) technical failure of TDC (n = 3), and (3) lack of discernible leakages in the transcatheter lymphangiography (n = 2). The clinical success of the TDE group was 89% (31/35), compared with 50% (5/10) of the non-TDE group. One major procedure-related complication was bile peritonitis caused by the needle passage of the distended gallbladder. CONCLUSIONS: Bail-out retrograde approach for TDC could improve the overall technical success of TDC significantly. KEY POINTS: • Bail-out retrograde thoracic duct access may improve the overall technical success of thoracic duct access, thus improving the clinical success of thoracic duct embolization.

Pragmatic role of noncontrast magnetic resonance lymphangiography in postoperative chylothorax or cervical chylous leakage as a diagnostic and preprocedural planning tool.

OBJECTIVES: To define the roles of noncontrast magnetic resonance lymphangiography (MRL) in the management of postoperative chylothorax or cervical chylous leakage. METHODS: A total of 50 consecutive patients underwent noncontrast MRL, intranodal lymphangiography, and thoracic duct embolization between May 2016 and April 2020. Their mean age was 62.6 years ± 10.3 (SD) years, and 35 of the participants were men. Conventional lymphangiographic images were sufficient in quality as a reference for the evaluation of diagnostic accuracy of leakage and location in 35 patients (70%) and for evaluation of anatomic details of the thoracic duct and jugulovenous junction in 34 patients (68%). RESULTS: MRL showed that the sensitivity, specificity, and positive and negative predictive values for leakage detection were 100%, 97.1%, 100%, and 100%, respectively, and the concordance rate was 97.14% (95% confidence interval [CI], 85.08-99.93%; p < .001). Leakage location was concordant between MRL and conventional lymphangiography in 27 patients (77.1%, 27/35). Regarding anatomical details of the thoracic duct, variation of the thoracic duct was missed in 11.7% of patients (4/34). The jugulovenous junction was observed in 91.1% (31/34), and its opening into the central vein was depicted in 76.4% (26/34). The concordance rate was between 76.47 and 91.18. CONCLUSIONS: Noncontrast MRL has a high sensitivity for the detection of postoperative thoracic and cervical chylous leakage but is suboptimal for the localization of the leak and depiction of anatomical details of the thoracic duct. This method is worthy of consideration as either a decision-making or planning tool for subsequent interventions. KEY POINTS: • Noncontrast MRL provides limited resolution images of CLS but has a high sensitivity for the detection of postoperative chylous leakage in the thoracic and neck regions. • Noncontrast MRL is suboptimal for depicting anatomic details in the thoracic duct and jugulovenous junction but can play a role as a decision-making and a planning tool for subsequent lymphatic interventions.

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.

Diaphragmatic perforation after transcatheter arterial chemoembolization of hepatocellular carcinoma via inferior phrenic artery: a case report.

BACKGROUND: Transcatheter arterial chemoembolization (TACE) via the inferior phrenic artery has been recognized to have its own therapeutic role without causing serious procedural complications. We report a case of diaphragmatic perforation after repeated TACE sessions conducted via the right inferior phrenic artery. CASE PRESENTATION: A 43-year-old man diagnosed with hepatocellular carcinoma was admitted to the hospital with a chief complaint of cough. The patient underwent TACE via the right inferior phrenic artery 3 months prior and was discharged without specific complications. Physical examination revealed decreased breathing sounds in the right lower lung zone. Chest radiograph demonstrated a small right pleural effusion. Chest CT scan revealed a small diaphragmatic perforation. The patient was unable to undergo surgical exploration, and a follow-up CT scan after 2 months revealed progression of the right diaphragmatic perforation with massive herniation of omental fat into the thoracic cavity. CONCLUSIONS: Although TACE via the inferior phrenic artery is a relatively safe procedure, it can be associated with rare but serious complications after repeated procedures. This is a rare case report of diaphragmatic perforation after TACE via the right inferior phrenic artery. Early recognition and prompt surgical management are essential to prevent catastrophic outcomes.

Circumflex Scapular Artery Pseudoaneurysm as an Unusual Source of Emboli in Recurrent Posterior Circulation Stroke.

OBJECTIVE: To present a rare cause of recurrent posterior embolic strokes originating from a partially thrombosed pseudoaneurysm of a shoulder artery after arthroscopy. MATERIALS AND METHODS: The clinical history, complementary studies and follow-up were reviewed. RESULTS: The patient was successfully embolized and presented no new ischemic episodes at the 3-month follow-up visit. CONCLUSIONS: Shoulder artery pseudoaneurysm should be considered as an unusual source of posterior embolic strokes.

[Clinical outcomes following microsurgery and endovascular embolization in the management of spinal dural arteriovenous fistula: A meta-analysis study].

OBJECTIVE: To compare the clinical effect of microsurgery and endovascular embolization in the treatment of spinal dural arteriovenous fistula (SDAVF) by meta-analysis. METHODS: A systematic review was performed to retrieve all relevant literature about surgical treatment or endovascular embolization of SDAVF up to December 2019 through PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials Results, CNKI, Wanfang Data, and SinoMed. The Chinese and English key words included: "SDAVF", "spinal dural arteriovenous fistula", "spinal AVM", "spinal vascular malformation and treatment". The included studies were evaluated using the Newcastle-Ottawa scale. The early failure rate, long-term recurrence, neurological recovery, and complications were evaluated and the clinical effects of the two methods in the treatment of SDAVF were compared by using RevMan 5.3 software. And a further subgroup analysis of the therapeutic effect of endovascular embolization with different embolic agents was conducted. RESULTS: A total of 46 studies involving 1 958 cases of SDAVF were included, in which 935 cases were treated by microsurgery and 1 023 cases were treated by endovascular embolization. The funnel plot demonstrated that there was no publication bias. The results of meta-analysis showed that the incidence of early surgical failure was lower than that of endovascular embolization (OR=0.20, 95%CI: 0.13-0.30, P < 0.05), and the long-term recurrence was also lower than that of endovascular embolization (OR=0.36, 95%CI: 0.22-0.58, P < 0.05). The improvement of neurological function in the surgical patients is significantly higher than that in the patients treated with endovascular embolization (OR=2.86, 95%CI: 1.36-5.99, P < 0.05). There was no significant difference in the occurrence of complications in these two groups (OR=1.52, 95%CI: 0.88-2.64, P=0.14). In the cases of endovascular embolization, the risk of treatment failure or recurrence was higher with Onyx glue than with n-butyl 2-cyanoacrylate (NBCA), and the difference was statistically significant (OR=4.70, 95%CI: 1.55-14.28, P < 0.05). CONCLUSION: Although the treatment of dural arteriovenous fistulas by intravascular embolization has been widely used, the clinical effect of microsurgery is still better than that of endovascular embolization. Large scale and high-quality randomized controlled trials are required to validate the efficacy and safety of endovascular treatment in SDAVF patients.

Portal vein embolization with N-butyl cyanoacrylate glue is superior to other materials: a systematic review and meta-analysis.

OBJECTIVES: It remains uncertain which embolization material is best for portal vein embolization (PVE). We investigated the various materials for effectiveness in inducing future liver remnant (FLR) hypertrophy, technical and growth success rates, and complication and resection rates. METHODS: A systematic review from 1998 to 2019 on embolization materials for PVE was performed on Pubmed, Embase, and Cochrane. FLR growth between the two most commonly used materials was compared in a random effects meta-analysis. In a separate analysis using local data (n = 52), n-butyl cyanoacrylate (NBCA) was compared with microparticles regarding costs, radiation dose, and procedure time. RESULTS: In total, 2896 patients, 61.0 ± 4.0 years of age and 65% male, from 51 papers were included in the analysis. In 61% of the patients, either NBCA or microparticles were used for embolization. The remaining were treated with ethanol, gelfoam, or sclerosing agents. The FLR growth with NBCA was 49.1% ± 29.7 compared to 42.2% ± 40 with microparticles (p = 0.037). The growth success rate with NBCA vs microparticles was 95.3% vs 90.7% respectively (p < 0.001). There were no differences in major complications between NBCA and microparticles. In the local analysis, NBCA (n = 41) entailed shorter procedure time and reduced fluoroscopy time (p < 0.001), lower radiation exposure (p < 0.01), and lower material costs (p < 0.0001) than microparticles (n = 11). CONCLUSION: PVE with NBCA seems to be the best choice when combining growth of the FLR, procedure time, radiation exposure, and costs. KEY POINTS: • The meta-analysis shows that n-butyl cyanoacrylate (NBCA) is superior to microparticles regarding hypertrophy of the future liver remnant, 49.1% ± 29.7 vs 42.2% ± 40.0 (p = 0.037). • There is no significant difference in major complication rates for portal vein embolization using NBCA, 4% (24/681), compared with microparticles, 5% (25/494) (p > 0.05). • Local data shows a shorter procedure time, 215 vs 348 mins from arrival to departure at the interventional radiology unit, and fluoroscopy time, 43 vs 96 mins (p < 0.001), lower radiation dosage, 573 vs 1287 Gycm2 (p < 0.01), and costs, €816 vs €4233 (p < 0.0001) for NBCA compared to microparticles.

Yttrium-90 radioembolization using MIRD dosimetry with resin microspheres.

OBJECTIVE: To review the technical feasibility of resin microsphere (SIR-Spheres®) yttrium-90 radioembolization prescribed using the medical internal radiation dose (MIRD) model. METHODS: All radioembolization procedures for hepatic malignancies using resin microspheres with MIRD model between November 2015 and February 2019 were included in this IRB-approved study (n = 60). Student's T test was used to compare prescribed activity based on MIRD and BSA models. Adverse events were assessed immediately, 30 days, and 6 months post-treatment. RESULTS: Sixty radioembolizations were performed in 54 patients (age 68 ± 9 years, 48-87 years, 35% female). Mean prescribed activity calculated by the MIRD model (target absorbed dose 120-200 Gy for primary and 80-200 Gy for metastatic liver cancers) was 1.7 GBq (0.3-6.4) compared with 0.6 GBq (0.12-2.1) if BSA had been used (p < 0.0001). The prescribed activity was successfully delivered in 93% (56/60) treatments. Prophylactic embolization and anti-reflux catheters were used in 20% (12/60) and 5% (3/60) treatments, respectively. No immediate post-procedural complications occurred. Abdominal pain was the most common clinical Grade 3 CTCAE in 30 days (10%) and 6 months (12%). Radiation pneumonitis occurred in 3 (5%) patients but no radiation-induced gastric ulcer or radiation-induced liver disease occurred. CONCLUSION: MIRD dosimetry results in higher prescribed activity compared with BSA dosimetry with resin microspheres. MIRD prescribed activity with target absorbed doses up to 200 Gy can be successfully administered without prophylactic embolization in selected patients. KEY POINTS: •MIRD dosimetry results in higher prescribed activity compared with BSA dosimetry for radioembolization. •MIRD dosimetry can be used for yttrium-90 resin microsphere radioembolization with acceptable safety profile.

Using prostate contrast retention (PCR) as the procedural endpoint in prostatic artery embolization for benign prostatic hyperplasia.

OBJECTIVES: The failure rate following prostate artery embolization (PAE) is around 20%, which may in part result from inadequate embolization. Prostate contrast retention (PCR) adequacy on immediate post-embolization cone-beam CT may provide better assessment of embolization completeness than arterial contrast stasis seen on fluoroscopy alone. The aim of this study was to evaluate outcomes of PAE using PCR adequacy as the procedural endpoint. METHODS: A retrospective cohort study of all PAE cases using this technique at a single large volume center was conducted. Following initial embolization of the main prostatic arteries, if PCR was inadequate, additional embolization was performed. Technical success (adequate PCR) was defined as > 75% global prostate gland contrast staining. Clinical success was determined in accordance to CIRSE standards of practice. RESULTS: One hundred sixty-five patients (mean age 68 ± 8.4 years) underwent PAE from June 2017 to March 2019. Technical and clinical success rates were 98.8% and 96.4% respectively. Clinical success rate was significantly higher in patients with adequate PCR. International Prostate Symptom Scores (IPSS) and Quality of Life (QoL) scores significantly improved at 1-, 3-, 6-, and 12-month follow-up when compared to baseline. Prostate volume (PV) and post-voiding residual bladder volume were significantly reduced at 3, 6, and 12 months in comparison to baseline. Mild (Clavien-Dindo grade I/II) and moderate (grade III) complication rates were 12.1% and 3.6% respectively. CONCLUSIONS: By using PCR adequacy as a guide to determine the procedure endpoint for PAE, it may be possible to achieve more complete embolization and thus higher clinical success rates. KEY POINTS: • By using PCR adequacy as a guide to determine the procedure endpoint for PAE, it may be possible to achieve more complete embolization and thus higher clinical success rates.

Retrograde transvenous obliteration for the prevention of variceal rebleeding in patients with portal vein thrombosis: a multicenter study.

OBJECTIVES: To evaluate the effectiveness of retrograde transvenous obliteration (RTO) for the prevention of variceal rebleeding in cirrhotic patients with portal vein thrombosis (PVT). METHODS: Consecutive cirrhotic patients with PVT who underwent RTO for the prevention of variceal rebleeding between January 2002 and June 2019 were included in this multicenter retrospective study. The primary outcome measure was rebleeding. The secondary outcome measures were survival, other complications of portal hypertension, liver function, and PVT. RESULTS: Forty-five patients (mean age, 66.0 ± 10.6 years; mean Model for End-Stage Liver Disease (MELD) score, 13.9 ± 5.5) were included. The 1-year actuarial probability of remaining free of rebleeding was 92.8 ± 4.0%. The 6-week, 1-year, and 3-year actuarial probabilities of survival were 79.8 ± 6.0%, 48.8 ± 7.7%, and 46.1 ± 7.9%, respectively. MELD score (hazard ratio (HR), 1.09 (95% confidence interval (CI), 1.01-1.17); p = .013) and ascites (HR, 2.84 (95% CI, 1.24-6.55); p = .014) were identified as significant predictors of survival. The 1-year actuarial probabilities of remaining free of new or worsening ascites and esophageal varices were 81.2 ± 8.7% and 89.2 ± 6.0%, respectively. No patients had overt hepatic encephalopathy during follow-up. MELD score significantly increased by a mean of 3.8 (95% CI, 1.7-6.0) at 3 months (p = .001). PVT had improved in 32.0%, worsened in 12.0%, and remained unchanged in 56.0% of patients at 3 months. CONCLUSION: RTO may be effective for the prevention of variceal rebleeding in cirrhotic patients with PVT. KEY POINTS: • Retrograde transvenous obliteration may prevent variceal rebleeding in cirrhotic patients with portal vein thrombosis. • The risks of other complications of portal hypertension may not be high after retrograde transvenous obliteration in cirrhotic patients with portal vein thrombosis. • Portal vein thrombosis may improve in approximately one-third of cirrhotic patients within 3 months after retrograde transvenous obliteration.

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.

Empiric cone-beam CT-guided embolization in acute lower gastrointestinal bleeding.

OBJECTIVES: To evaluate the clinical effect and safety of cone-beam CT (CBCT)-guided empirical embolization for acute lower gastrointestinal bleeding (LGIB) in patients with a positive CT angiography (CTA) but subsequent negative digital subtraction angiography (DSA). METHODS: A retrospective study of consecutive LGIB patients with a positive CTA who received a DSA within 24 h from January 2008 to July 2019. Patients with a positive DSA were treated with targeted embolization (TE group). Patients with a negative DSA underwent an empiric CBCT-guided embolization of the assumed ruptured vas rectum (EE group) or no embolization (NE group). Recurrent bleeding, major ischemic complications, and in-hospital mortality were compared by means of Fisher's exact test. Further subgroup analysis was performed on hemodynamic instability. RESULTS: Eighty-five patients (67.6 years ± 15.7, 52 men) were included (TE group, n = 47; EE group, n = 19; NE group, n = 19). If DSA was positive, technical success of targeted embolization was 100% (47/47). If DSA was negative and the intention to treat by empiric CBCT-guided embolization, technical success was 100% (19/19). Recurrent bleeding rates in the TE group, EE group, and NE group were 17.0% (8/47), 21.1% (4/19), and 52.6% (10/19) respectively. Empiric CBCT-guided embolization reduced rebleeding significantly in patients with a negative DSA and hemodynamic instability (EE group, 3/10 vs NE group, 10/12, p = .027). Major ischemic complications occurred in one patient (TE group). Overall, the in-hospital mortality rate was 7.1% (6/85). CONCLUSION: Empiric cone-beam CT-guided embolization proved to be a feasible, effective, and safe treatment strategy to reduce rebleeding and improve clinical success in hemodynamically unstable patients with acute LGIB, positive CTA but negative DSA. KEY POINTS: • A novel transarterial embolization technique guided by cone-beam CT could be developed extending the "empiric" embolization strategy to lower gastrointestinal bleeding. • By implementing the empiric treatment strategy, nearly all patients with an active lower gastrointestinal bleeding on CTA will be eligible for a superselective empiric embolization, even if subsequent catheter angiography is negative. • In patients with a negative catheter angiography, empiric embolization reduces the rebleeding rate and, particularly in hemodynamically unstable patients, improves clinical success compared with a conservative "wait-and-see" management.

Tortuosity of superior cerebral veins: Comparative magnetic resonance imaging morphometrics in normal subjects and arteriovenous malformation patients.

Blood vessel tortuosity results from increased diameter and length in response to higher hemodynamic loads. Tortuosity metrics have not been determined for abnormal superior cerebral veins (SCVs) draining cerebral arteriovenous malformations (AVMs). Draining vein (DV) tortuosity may influence safety and efficacy of retrograde microcatheter navigation during transvenous treatment of pial AVMs. Here, we quantify SCV tortuosity in normal subjects and AVM patients using two image segmentation methods. We used contrast-enhanced brain magnetic resonance (MR) images to define the axis of each SCV through a regularly spaced set of three-dimensional (3D) points defining its skeleton curve. We then calculated two metrics: the "sum of angles metric" (SOAM), which adds all angles of curvature along a vessel and normalizes by vessel length, and the "distance metric" (DM), a tortuosity measure providing a ratio of vessel length to linear distance between vessel endpoints. We analyzed 168 metrics in 43 veins of eight normal subjects and 41 veins of seven AVM patients. In normal subjects, the mean SOAM and DM for SCVs were 21.34 ± 7.49 °/mm and 1.42 ± 0.25, respectively. In AVM patients, DVs had a significantly higher mean SOAM of 30.43 ± 11.38 °/mm (p = .02) and DM of 2.79 ± 1.77 (p = .01) than normal subjects. In AVM patients, DVs were significantly more tortuous than matched contralateral uninvolved SCVs, which were similar in tortuosity to normal subject SCVs. We thus report normative tortuosity metrics of brain SCVs and show that AVM cortical DVs are significantly more tortuous than normal SCVs. Knowledge of these comparative tortuosities is valuable in planning endovenous AVM embolotherapies.