CT analysis of aortic calcifications to predict abdominal aortic aneurysm rupture.

BACKGROUND: Abdominal aortic aneurysm (AAA) rupture prediction based on sex and diameter could be improved. The goal was to assess whether aortic calcification distribution could better predict AAA rupture through machine learning and LASSO regression. METHODOLOGY: In this retrospective study, 80 patients treated for a ruptured AAA between January 2001 and August 2018 were matched with 80 non-ruptured patients based on maximal AAA diameter, age, and sex. Calcification volume and dispersion, morphologic, and clinical variables were compared between both groups using a univariable analysis with p = 0.05 and multivariable analysis through machine learning and LASSO regression. We used AUC for machine learning and odds ratios for regression to measure performance. RESULTS: Mean age of patients was 74.0 ± 8.4 years and 89% were men. AAA diameters were equivalent in both groups (80.9 ± 17.5 vs 79.0 ± 17.3 mm, p = 0.505). Ruptured aneurysms contained a smaller number of calcification aggregates (18.0 ± 17.9 vs 25.6 ± 18.9, p = 0.010) and were less likely to have a proximal neck (45.0% vs 76.3%, p < 0.001). In the machine learning analysis, 5 variables were associated to AAA rupture: proximal neck, antiplatelet use, calcification number, Euclidian distance between calcifications, and standard deviation of the Euclidian distance. A follow-up LASSO regression was concomitant with the findings of the machine learning analysis regarding calcification dispersion but discordant on calcification number. CONCLUSION: There might be more to AAA calcifications that what is known in the present literature. We need larger prospective studies to investigate if indeed, calcification dispersion affects rupture risk. CLINICAL RELEVANCE STATEMENT: Ruptured aneurysms are possibly more likely to have their calcification volume concentrated in a smaller geographical area. KEY POINTS: • Abdominal aortic aneurysm (AAA) rupture prediction based on sex and diameter could be improved. • For a given calcification volume, AAAs with well-distributed calcification clusters could be less likely to rupture. • A machine learning model including AAA calcifications better predicts rupture compared to a model based solely on maximal diameter and sex alone, although it might be prone to overfitting.

Hepatic Hilar Nerve Block for Adjunctive Analgesia during Percutaneous Thermal Ablation of Hepatic Tumors: A Retrospective Analysis.

PURPOSE: To determine whether hepatic hilar nerve block techniques reduce analgesic and sedation requirements during percutaneous image-guided thermal ablation of hepatic tumors. MATERIALS AND METHODS: A single-center retrospective cohort analysis was performed of 177 patients (median age, 67 years; range, 33-86 years) who underwent percutaneous image-guided thermal ablation of liver tumors. All patients were treated utilizing local anesthetic and moderate sedation between November 2018 and November 2021 at a tertiary level hospital, with or without the administration of a hepatic hilar nerve block. Univariable and multivariable linear regression analyses were performed to determine the relationship between the administration of the hilar nerve block and fentanyl and midazolam dosages. RESULTS: A total of 114 (64%) patients received a hilar nerve block in addition to procedural sedation, and 63 (36%) patients received procedural sedation alone. There were no significant differences in the baseline demographic and tumor characteristics between the cohorts. The procedure duration was longer in the hilar block cohort than in the unblocked cohort (median, 95 vs 82 minutes; P = .0012). The technical success rate (98% in both the cohorts, P = .93) and adverse event rate (11% vs 3%, P = .14) were not significantly different between the cohorts. After adjusting for patient and tumor characteristics, ablation modality, and procedure and ablation durations, hilar nerve blocks were associated with lower fentanyl (-18.4%, P = .0045) and midazolam (-22.7%, P = .0007) dosages. CONCLUSIONS: Hepatic hilar nerve blocks significantly decrease the fentanyl and midazolam requirements during thermal ablation of hepatic tumors, without a significant change in the technical success or adverse event rates.

Hepatic Hilar Nerve Block for Hepatic Interventions: Anatomy, Technique, and Initial Clinical Experience in Thermal Ablation of Liver Tumors.

Background Image-guided procedures for treatment of liver diseases can be painful and require heavy sedation of the patient. Local-regional nerve blocks improve pain control and reduce oversedation risks, but there are no documented liver-specific nerve blocks. Purpose To develop a safe and technically simple liver-specific nerve block. Materials and Methods Between March 2017 and October 2019, three cadavers were dissected to evaluate the hepatic hilar anatomy. The hepatic hilar nerves were targeted with transhepatic placement of a needle adjacent to the main portal vein, under US guidance, and evaluated with use of an injection of methylene blue. A hepatic nerve block, using similar technique and 0.25% bupivacaine, was offered to patients undergoing liver tumoral ablation. In a prospective pilot study, 12 patients who received the nerve block were compared with a control group regarding complications, safety, pain scores, and intraoperative opioid requirement. Student t tests were used to compare the groups' characteristics, and Mann-Whitney U tests were used for the measured outcomes. Results Cadaver results confirmed that the hepatic nerves coursing in the hepatic hilum can be targeted with US for injection of anesthetic agents, with adequate spread of injected methylene blue around the nerves in the hepatic hilar perivascular space. The 12 participants (mean age ± standard deviation, 66 years ± 13; eight men) who received a hepatic hilar block before liver thermal ablations demonstrated reduced pain compared with a control group of 12 participants (mean age, 63 years ± 15; eight men) who received only intravenous sedation. Participants who received the nerve block had a lower mean visual analog scale score for pain than the control group (3.9 ± 2.4 vs 7.0 ± 2.8, respectively; P = .01) and decreased need for intraprocedural fentanyl (mean dose, 152 µg ± 78.0 vs 235.4 µg ± 58.2, respectively; P = .01). No major complications occurred in the hepatic hilar nerve block group. Conclusion A dedicated hepatic hilar nerve block with 0.25% bupivacaine can be safely performed to provide anesthesia during liver tumoral ablation. © RSNA, 2021.

Transhepatic Approach for Retrograde D2 Duodenal Stent Placement: New Technique and Case Series.

Transhepatic duodenal stent placement may be a solution when endoscopy fails or when duodenal and biliary stents are needed simultaneously. This approach is usually not considered as an option when the duodenal stent must be deployed across the ampulla of Vater. The authors present a series of 10 patients who underwent a novel transhepatic technique to place a duodenal stent across the ampulla of Vater by establishing a wire scaffold from the liver toward the jejunum and then curving back on itself retrogradely through the duodenal tumor and out the mouth. Technical success was 90% with no associated mortality.

Creating Low-Cost Phantoms for Needle Manipulation Training in Interventional Radiology Procedures.

Image-guided procedures play a critical role in the clinical practice of radiologists. Training radiology residents in these procedures, with early teaching of basic but fundamental skills, is therefore crucial to develop competence before they become autonomous and start their practice. It has been proposed in the literature that low-fidelity phantoms are appropriate to teach novice trainees. The authors propose a series of phantoms to teach the core skills necessary to perform procedures early in resident training. The phantoms described can be used to train skills necessary for performing US-guided biopsy, US-guided vascular puncture, cone-beam CT drainage, and fluoroscopy-guided lumbar puncture, as well as using the parallax effect to determine relative position at fluoroscopy. Phantoms are a valuable training tool, although it is important to consider the teaching audience when choosing or creating a model. For novices, a range of inexpensive low-fidelity gelatin-based phantoms can be used to train core skills in image-guided procedures. The online slide presentation from the RSNA Annual Meeting is available for this article. ©RSNA, 2021.

Predictors of Mortality from Spontaneous Soft-Tissue Hematomas in a Large Multicenter Cohort Who Underwent Percutaneous Transarterial Embolization.

Purpose To evaluate the safety and efficacy of percutaneous transarterial embolization (PTAE) for the treatment of spontaneous soft-tissue hematomas (SSTHs) and identify variables predictive of short-term outcome. Materials and Methods Between 2011 and 2017, the outcome was retrospectively analyzed for 112 patients (mean age ± standard deviation, 72 years ± 14; range, 28-92 years), including 65 women (mean age, 73 years ± 12.7; range, 39-92 years) and 47 men (mean age, 70 years ± 14.9; range, 28-91 years), with SSTH treated with PTAE. Thirty-day mortality, technical and clinical success, simplified acute physiology score (SAPS) II, anticoagulation, embolic agent, hematoma volume and location, serum hemoglobin level, hemodynamic instability, and presence of active bleeding at CT and/or angiography were recorded. Clinical success was defined as cessation of bleeding as determined by hemodynamic stability and/or serum hemoglobin level stabilization after PTAE. Univariable and multivariable analyses were performed by using a Cox model to identify variables associated with time to death. Results Mortality rate was 26.8% (30 of 112 patients), angiographic success rate was 95.5% (107 of 112 patients), and clinical success rate was 83% (93 of 112 patients). For surviving patients, mean SAPS II was 19.6 ± 7.1 (range, 13-31) and mean hematoma volume was 862 cm3 ± 618 (range, 238-1887 cm3). For deceased patients, mean SAPS II was 42 ± 13.2 (range, 18-63) and mean hematoma volume was 1419 cm3 ± 788 (range, 251-3492 cm3). SAPS II (P < .001), hematoma volume (P = .01), and retroperitoneal location (P = .01) were independently associated with fatal outcome. Conclusion Percutaneous transarterial embolization is effective for the emergency treatment of spontaneous soft-tissue hematomas. Simplified acute physiology score II, hematoma volume, and retroperitoneal location are predictors of short-term outcome. © RSNA, 2019 Online supplemental material is available for this article.

Superior Hypogastric Nerve Block as Post-Uterine Artery Embolization Analgesia: A Randomized and Double-Blind Clinical Trial.

Purpose To evaluate the effectiveness of superior hypogastric nerve block (SHNB) in reducing narcotic use after uterine artery embolization (UAE). Materials and Methods This study was a prospective, randomized, double-blind, parallel clinical trial in patients referred to a tertiary care university teaching hospital for UAE. Forty-four participants were enrolled (mean age, 46 years; range, 32-56 years). No consenting patient was excluded. All participants were randomized 1:1 to undergo either a sham procedure or SHNB. There were 22 participants in each group. One participant was lost to follow-up regarding home survey results. Use of narcotics and antiemetics was recorded in-hospital. Pain scores were recorded at home for 10 days with use of a visual analog scale (range, 1-10). Statistical analysis was performed by using the t test and χ2 test, with P < .05 considered indicative of a statistically significant difference. The full study protocol can be found at www.clinicaltrials.gov (NCT02270255). Results Participant demographic characteristics, fibroid volume, symptoms, and perceived sensitivity to pain were similar in both groups. Immediately after embolization, the pain score was lower in the SHNB group than in the sham group (mean, 1.0 ± 2.1 vs 2.6 ± 2.0, respectively; P = .01). The total need for fentanyl in the postanesthesia care unit was lower in the SHNB group than in the sham group (mean, 56 µg ± 67 vs 124 µg ± 91, respectively; P = .009). The morphine-equivalent dose needed was lower in the SHNB group than in the sham group (mean, 5.1 mg ± 5.8 vs 11.0 mg ± 9.0, respectively; P = .014). Of the 22 participants in the SHNB group, five (23%) needed antiemetics versus 12 of 22 participants (55%) in the sham group (P = .03). No difference in hospital admissions was observed between the two groups, and no major complications occurred from the SHNB. Conclusion Use of superior hypogastric nerve block reduces the amount of pain-related narcotics and antiemetics after uterine artery embolization. © RSNA, 2018.

Spontaneous Retroperitoneal Hematomas Following Uncomplicated Vaginal Deliveries: A Case Report and Literature Review.

INTRODUCTION: Retroperitoneal hematomas are rare in obstetrics. CASE PRESENTATION: A 36-year-old female presented two days following uncomplicated non-traumatic spontaneous vaginal delivery with an acute onset of severe left lower quadrant abdominal pain. The patient was hypotensive, tachycardic, and febrile. The hemoglobin dropped post delivery to 75 g/L. A non-contrast CT scan revealed a retroperitoneal hematoma. MANAGEMENT AND OUTCOME: Conservative management approaches resulted in spontaneous remission of the retroperitoneal hematoma.

Portal Vein Embolization in the Setting of Staged Hepatectomy with Preservation of Segment IV ± I Only for Bilobar Colorectal Liver Metastases: Safety, Efficacy, and Clinical Outcomes.

PURPOSE: To assess frequency of adverse events, efficacy, and clinical outcomes of percutaneous portal vein embolization (PVE) in patients with bilobar colorectal liver metastases undergoing staged hepatectomy with preservation of segment IV ± I only. MATERIALS AND METHODS: Retrospective analysis was performed of 40 consecutive patients who underwent right PVE after successful left lobectomy between 2005 and 2013. Rates of adverse events, future liver remnant (FLR) > 30% compared with baseline liver volume, clinical success (completion of staged hepatectomy with clearance of liver metastases), and overall survival were analyzed. RESULTS: PVE was performed using polyvinyl alcohol particles (n = 7; 17.5%), particles plus coils (n = 23; 57.5%), and N-butyl cyanoacrylate glue plus ethiodized oil (n = 10; 25%). Technical success was 100%. After PVE, 20% (n = 8) of patients exhibited portal venous thrombosis, ranging from isolated intrahepatic portal branch thrombosis to massive thrombosis of the main portal vein (n = 3) and responsible for periportal cavernoma and portal hypertension in 5 patients. Of patients, 23 (57.5%) had FLR ≥ 30%, and 21 (52.5%) had clinical success. Six patients had significant stenosis or occlusion of the left portal vein or biliary system after original left lobectomy, which was independently associated with FLR < 30% (R2 = 0.24). Clinical success was the only independent variable associated with survival (R2 = 0.25). CONCLUSIONS: PVE for staged hepatectomy with preservation of segment IV ± I only is technically feasible, leading to adequate hypertrophy and clinical success rates in these patients with poor oncologic prognosis. Portal venous thrombosis is greater after the procedure than in the setting of standard PVE.

Neoadjuvant chemotherapy does not impair liver regeneration following hepatectomy or portal vein embolization for colorectal cancer liver metastases.

BACKGROUND AND OBJECTIVES: Treatment strategies for colorectal cancer liver metastasis (CRCLM) such as major hepatectomy and portal vein embolization (PVE) rely on liver regeneration. We aim to investigate the effect of neoadjuvant chemotherapy on liver regeneration occurring after PVE and after major hepatectomy. METHODS: CRCLM patients undergoing PVE or major resection were identified retrospectively from our database. Liver regeneration data (expressed as future liver remnant [FLR] and percentage of liver regeneration [%LR]), total liver volume (TLV) and clinical characteristics were collected. RESULTS: Between 2003 and 2013, 226 patients were included (85 major resection, 141 PVE). The median chemotherapy cycles was six in both groups. The median time interval between the last chemotherapy and the intervention was 51 days in the PVE group and 79 days in the hepatectomy group. In the PVE group, chemotherapy was not associated with altered liver regeneration (number of cycles [P = 0.435], timing [P = 0.563], or chemotherapy agent [P = 0.116]). Similarly in the major hepatectomy group, preoperative chemotherapy (number of cycles [P = 0.114]; agent [P = 0.061], timing [P = 0.126]) were not significantly associated with differences in liver regeneration (P = 0.592). In both groups, the predicted FLR% was inversely correlated with the %LR (P < 0.001). CONCLUSION: Chemotherapy does not affect liver regeneration following PVE or major resection. J. Surg. Oncol. 2016;113:449-455. © 2016 Wiley Periodicals, Inc.

Involvement of Toso in activation of monocytes, macrophages, and granulocytes.

Rapid activation of immune responses is necessary for antibacterial defense, but excessive immune activation can result in life-threatening septic shock. Understanding how these processes are balanced may provide novel therapeutic potential in treating inflammatory disease. Fc receptors are crucial for innate immune activation. However, the role of the putative Fc receptor for IgM, known as Toso/Faim3, has to this point been unclear. In this study, we generated Toso-deficient mice and used them to uncover a critical regulatory function of Toso in innate immune activation. Development of innate immune cells was intact in the absence of Toso, but Toso-deficient neutrophils exhibited more reactive oxygen species production and reduced phagocytosis of pathogens compared with controls. Cytokine production was also decreased in Toso(-/-) mice compared with WT animals, rendering them resistant to septic shock induced by lipopolysaccharide. However, Toso(-/-) mice also displayed limited cytokine production after infection with the bacterium Listeria monocytogenes that was correlated with elevated presence of Listeria throughout the body. Accordingly, Toso(-/-) mice succumbed to infections of L. monocytogenes, whereas WT mice successfully eliminated the infection. Taken together, our data reveal Toso to be a unique regulator of innate immune responses during bacterial infection and septic shock.

Superior vena cava syndrome: role of the interventionalist.

Superior vena cava syndrome results from the obstruction of blood flow through the superior vena cava and is most often due to thoracic malignancy. However, benign etiologies are on the rise secondary to more frequent use of intravascular devices such as central venous catheters and pacemakers. Although rarely a medical emergency, the symptoms can be alarming, particularly to the patient. Traditionally, superior vena cava syndrome has been managed with radiotherapy and chemotherapy. But interventional endovascular techniques have made inroads that offer a safe, rapid, and durable response. In many cases, it may be the only reasonable treatment. Because of this, an approach to endovascular treatment of this condition must be in the armamentarium of the interventional radiologist. This review will provide the reader with an insight into the etiology, pathophysiology, and various management principles of superior vena cava syndrome. The focus will be on understanding the techniques used during various endovascular interventions, including angioplasty, stenting, and pharmacomechanical thrombolysis. Discussion will also be centred on possible complications and current evidence as well as controversies regarding these approaches.

Prostatic artery embolization for intractable hematuria in patients with unregulated coagulation parameters: three case reports.

INTRODUCTION: Benign prostatic hyperplasia is a prevalent disease that could be responsible of severe intractable hematuria requiring invasive surgical management. CASE PRESENTATION: We report three high-risk cases presented with intractable hematuria of prostatic origin with high medical co-morbidities treated safely and effectively by prostatic artery embolization with favorable outcomes. CONCLUSIONS: In non-surgical, anticoagulated patients, prostatic artery embolization represents a safe and effective intervention for the treatment of intractable hematuria related to benign prostatic hyperplasia.

In situ trapping of activated initiator caspases reveals a role for caspase-2 in heat shock-induced apoptosis.

Activation of 'initiator' (or 'apical') caspases-2, -8 or -9 (refs 1-3) is crucial for induction of apoptosis. These caspases function to activate executioner caspapses that, in turn, orchestrate apoptotic cell death. Here, we show that a cell-permeable, biotinylated pan-caspase inhibitor (bVAD-fmk) both inhibited and 'trapped' the apical caspase activated when apoptosis was triggered. As expected, only caspase-8 was trapped in response to ligation of death receptors, whereas only caspase-9 was trapped in response to a variety of other apoptosis-inducing agents. Caspase-2 was exclusively activated in heat shock-induced apoptosis. This activation of caspase-2 was also observed in cells protected from heat-shock-induced apoptosis by Bcl-2 or Bcl-xL. Reduced sensitivity to heat-shock-induced death was observed in caspase-2(-/-) cells. Furthermore, cells lacking the adapter molecule RAIDD failed to activate caspase-2 after heat shock treatment and showed resistance to apoptosis in this setting. This approach unambiguously identifies the apical caspase activated in response to apoptotic stimuli, and establishes caspase-2 as a proximal mediator of heat shock-induced apoptosis.

Joint-sparing reconstruction for extensive periacetabular metastases: Literature review and a novel minimally invasive surgical technique.

Classically, patients with advanced lytic disease of the acetabulum secondary to metastatic bone disease are treated with complex arthroplasty reconstruction techniques. Advancements in percutaneous techniques have extended the indications for safer, minimally invasive procedures for patients with periacetabular metastasis without the need for complex hip replacement and the complications that follow it. The purpose of this report is to revisit the management of this group of patients and provide indications for an alternative minimally invasive joint-sparing technique. We describe a novel technique using a combination of percutaneous cryoablation, cementoplasty and two-screw fixation. With careful consideration of indications, excellent functional and oncologic outcomes one year after surgery is possible without the need for additional procedures.

Embolization of pulmonary arteriovenous malformations with amplatzer vascular plugs: safety and midterm effectiveness.

PURPOSE: To evaluate the safety and effectiveness of Amplatzer vascular plugs (AVPs) for percutaneous closure of arteries feeding pulmonary arteriovenous malformations (PAVMs). MATERIALS AND METHODS: Over a 45-month period, 24 consecutive patients with at least one PAVM treated with an AVP were selected from a database on patients with a PAVM who received embolotherapy. Immediate technical success was defined as the complete absence of flow through the PAVM after embolization without the need for additional embolization material. Success on follow-up imaging was defined as a reduction in size of at least 70% of the aneurysm or draining vein on follow-up computed tomography or the absence of flow through the PAVM on a subsequent pulmonary angiogram. RESULTS: Thirty-seven AVPs were used to close 36 feeding arteries in 35 PAVMs in seven male and 17 female patients aged 11-86 years (mean age, 50 y). Technical success was achieved in 35 feeding arteries (97%). One feeding artery required two AVPs for closure. There were no immediate procedure-related complications. At a mean clinical follow-up of 322 days (range, 1-1,126 d), all patients were alive without new PAVM-related complications. Imaging follow-up was available for 29 embolized vessels (81%) with a mean follow-up of 418 days (range, 40-937 d), and recanalization occurred in two treated vessels (7%). CONCLUSIONS: AVPs are safe and effective for closure of PAVMs feeding vessels that can be reached with a guiding catheter, with an acceptable rate of recanalization.