Synergy in IR-Hybrid CT/C-arm in the setting of critical trauma.

Access to multi-detector computed tomography (MDCT) scanning for interventional procedures can prove to be logistically challenging as resources are often in different areas within the hospital. At some institutions, interventional radiology suites have moved to the operating room, separate from the diagnostic radiology department. At these institutions, complex interventional procedures requiring both fluoroscopy and MDCT may pose logistical challenges, especially as they pertain to timely patient transfers. Hybrid CT/fluoroscopy suite provides rapid, reliable MDCT assessment of trauma patients before and after emergent surgery, as well as access to the entire spectrum of emergent image-guided interventions in the same suite.

Hereditary Hemorrhagic Telangiectasia: The Convergence of Genotype, Phenotype, and Imaging in Modern Diagnosis and Management of a Multisystem Disease.

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disease that manifests as vascular malformations in the brain, lung, liver, gastrointestinal tract, nasal mucosa, and skin. Diagnosis and management of HHT is guided in large part by imaging studies, making it a condition with which the radiology community needs familiarity. Proper screening and care lead to improved morbidity and mortality in patients with HHT. International guidelines were recently updated and form the basis for a detailed discussion of the role of imaging and image-guided therapy in HHT. © RSNA, 2021 Online supplemental material is available for this article.

An international, multicenter study of intravenous bevacizumab for bleeding in hereditary hemorrhagic telangiectasia: the InHIBIT-Bleed study.

Hereditary hemorrhagic telangiectasia (HHT, Osler-Weber-Rendu disease) is a rare multisystem vascular disorder causing chronic gastrointestinal bleeding, epistaxis, and severe anemia. Bevacizumab, an anti-vascular endothelial growth factor antibody, may be effective to treat bleeding in HHT. This international, multicenter, retrospective study evaluated the use of systemic bevacizumab to treat HHT-associated bleeding and anemia at 12 HHT treatment centers. Hemoglobin, epistaxis severity score, red cell units transfused, and intravenous iron infusions before and after treatment were evaluated using paired means testing and mixed-effects linear models. 238 HHT patients received bevacizumab for a median of 12 (range, 1-96) months. Compared with pretreatment, bevacizumab increased mean hemoglobin by 3.2 g/dL (95% CI, 2.9-3.5 g/dL) [mean hemoglobin 8.6 (8.5, 8.8) g/dL versus 11.8 (11.5, 12.1) g/dL, p<0.0001)] and decreased the epistaxis severity score (ESS) by 3.4 (3.2-3.7) points [mean ESS 6.8 (6.6-7.1) versus 3.4 (3.2-3.7), P<0.0001] during the first year of treatment. Compared with 6 months pretreatment, RBC units transfused decreased by 82% [median of 6.0 (IQR 0.0-13.0) units versus 0 (IQR, 0.0-1.0) units, P<0.0001] and iron infusions decreased by 70% [median of 6.0 (1.0-18.0) infusions versus 1.0 (0.0-4.0) infusions, P<0.0001] during the first 6 months of bevacizumab treatment. Outcomes were similar regardless of underlying pathogenic mutation. Following initial induction infusions, continuous/scheduled bevacizumab maintenance achieved higher hemoglobin and lower ESS than intermittent/as needed maintenance but with more drug exposure. Bevacizumab was well tolerated: hypertension, fatigue, and proteinuria were the most common adverse events. Venous thromboembolism occurred in 2% of patients. In conclusion, systemic bevacizumab was safe and effective to manage chronic bleeding and anemia in HHT.

Second International Guidelines for the Diagnosis and Management of Hereditary Hemorrhagic Telangiectasia.

DESCRIPTION: Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disease with an estimated prevalence of 1 in 5000 that is characterized by the presence of vascular malformations (VMs). These result in chronic bleeding, acute hemorrhage, and complications from shunting through VMs. The goal of the Second International HHT Guidelines process was to develop evidence-based consensus guidelines for the management and prevention of HHT-related symptoms and complications. METHODS: The guidelines were developed using the AGREE II (Appraisal of Guidelines for Research and Evaluation II) framework and GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology. The guidelines expert panel included expert physicians (clinical and genetic) in HHT from 15 countries, guidelines methodologists, health care workers, health care administrators, patient advocacy representatives, and persons with HHT. During the preconference process, the expert panel generated clinically relevant questions in 6 priority topic areas. A systematic literature search was done in June 2019, and articles meeting a priori criteria were included to generate evidence tables, which were used as the basis for recommendation development. The expert panel subsequently convened during a guidelines conference to conduct a structured consensus process, during which recommendations reaching at least 80% consensus were discussed and approved. RECOMMENDATIONS: The expert panel generated and approved 6 new recommendations for each of the following 6 priority topic areas: epistaxis, gastrointestinal bleeding, anemia and iron deficiency, liver VMs, pediatric care, and pregnancy and delivery (36 total). The recommendations highlight new evidence in existing topics from the first International HHT Guidelines and provide guidance in 3 new areas: anemia, pediatrics, and pregnancy and delivery. These recommendations should facilitate implementation of key components of HHT care into clinical practice.

Gallbladder Cryoablation for Chronic Cholecystitis in High-Risk Surgical Patients: 1-Year Clinical Experience with Imaging Follow-up.

PURPOSE: To assess the short-term safety and efficacy of gallbladder cryoablation in high-risk patients. MATERIALS AND METHODS: A single-center, retrospective review of clinical and imaging follow-up from patients who were referred for gallbladder cryoablation between August 2018 and July 2019 was performed. All patients had serious pre-procedural comorbidities and were unacceptable surgical candidates (mean age, 52.5 years; mean American Society of Anesthesiologists score, 3.67). Primary efficacy measures included technical success, absence of symptoms after cholecystostomy tube removal, and imaging evidence of cystic duct obstruction and gallbladder involution. The primary safety measure was the absence of Society of Interventional Radiology moderate or greater adverse events. RESULTS: Technical success was 86%, with 1 of 7 patients unable to undergo cryoablation because of adhesions preventing hydrodissection of the colon away from the gallbladder. Mean duration of clinical follow-up after discharge was 278 days (range, 59-498 days). Abdominal pain was absent in all patients after ablation. Cholecystostomy tubes were removed immediately after ablation (n = 5) or on post-procedure day 11 (n = 1). Computed tomography or magnetic resonance imaging was obtained at 1-3 months (n = 6), 4-6 months (n = 4), and 6-12 months (n = 5) after the procedure and demonstrated gallbladder involution in 5 of 6 patients. One patient had asymptomatic distention of the gallbladder on follow-up imaging. Hepatobiliary iminodiacetic acid scans were completed in 5 of 6 patients 1 month after ablation and demonstrated cystic duct occlusion in all 5 patients. One moderate adverse event (infection) and 1 life-threatening adverse event (hemorrhage) occurred. CONCLUSIONS: Gallbladder cryoablation might be a viable treatment option for high-risk patients with gallbladder disease and warrants further investigation.

First in-Human Gallbladder Cryoablation in a Patient with Acute Calculous Cholecystitis Initially Treated with a Cholecystostomy Tube.

A 71-year-old poor surgical candidate with acute calculous cholecystitis was initially managed with cholecystostomy tube drainage for 28 days. He subsequently underwent gallbladder cryoablation under moderate sedation with 3 cryoprobes and 2 separate 10-8-10 freeze-thaw cycles targeting the gallbladder neck/body and fundus followed by cholecystostomy tube removal. He was discharged 1 day after ablation. Magnetic resonance and hepatobiliary iminodiacetic acid scan 1 month postablation demonstrated a thick-walled, distended gallbladder and no filling of the cystic duct. Magnetic resonance 3 months postablation demonstrated retraction of the gallbladder wall with luminal collapse. The patient denied any pain after discharge and is asymptomatic 3 months after ablation.

Endovascular Biopsy and Endothelial Cell Gene Expression Analysis of Dialysis Arteriovenous Fistulas: A Feasibility Study.

PURPOSE: To demonstrate feasibility of endothelial cell (EC) biopsy from dialysis arteriovenous fistulas (AVFs) with the use of guidewires and to characterize gene expression differences between ECs from stenotic and nonstenotic outflow vein segments. MATERIALS AND METHODS: Nine consecutive patients undergoing fistulography for AVF dysfunction from June to August 2016 were enrolled. ECs were biopsied with the use of guidewires from venous outflow stenoses and control outflow veins central to the stenoses. ECs were sorted with the use of flow cytometry, and the Fluidigm Biomark HD system was used for single-cell quantitative polymerase chain reaction (qPCR) analysis of gene expression. Forty-eight genes were assessed and were selected based on different cellular functions and previous literature. Linear mixed models (LMMs) were used to identify differential gene expression between the groups, and self-organizing maps (SOMs) were used to identify cell clusters based on gene coexpression profiles. RESULTS: A total of 219 and 213 ECs were sampled from venous outflow stenoses and control vein segments, respectively. There were no immediate biopsy-related complications. Forty-eight cells per patient were sorted for qPCR analysis. LMM identified 7 genes with different levels of expression at stenotic segments (P < .05), including AGTR-2, HMOX-2, MTHFR, SERPINC-1, SERPINE-1, SMAD-4, and VWF. SOM analysis identified 4 cell clusters with unique gene expression profiles, each containing stenotic and control ECs. CONCLUSIONS: EC biopsy from dialysis AVFs with the use of guidewires is feasible. Gene expression data suggest that genes involved in multiple cellular functions are dysregulated in stenotic areas. SOMs identified 4 unique clusters of cells, indicating EC phenotypic heterogeneity in outflow veins.

Operator Dose Reduction during Transjugular Liver Biopsy Using a Radiation-Attenuating Drape: A Prospective, Randomized Study.

PURPOSE: To assess the effectiveness of disposable radiation-absorbing surgical drapes on operator radiation dose during transjugular liver biopsy (TJLB). MATERIALS AND METHODS: This dual-arm prospective, randomized study was conducted between May 2017 and January 2018 at a single institution. TJLB procedures (N = 62; patient age range, 19-80 y) were assigned at a 1:1 ratio to the use of radiation-absorbing surgical drapes or standard surgical draping. The primary outcome was cumulative radiation equivalent dose incident on the operator, as determined by an electronic personal dosimeter worn at the chest during each procedure. Cumulative kerma-area product (KAP), total fluoroscopy time, and total number of exposures used during each liver biopsy procedure were also determined. RESULTS: Mean radiation dose incident on the operator decreased by 56% with the use of radiation-absorbing drapes (37 µSv ± 35; range, 4-183 µSv) compared with standard draping (84 µSv ± 58; range, 11-220 µSv). Radiation incident on the patient was similar between groups, with no significant differences in mean KAP, total fluoroscopy time, and number of exposures acquired during the procedures. CONCLUSIONS: Use of disposable radiation-absorbing drapes reduces scatter radiation to interventionalists performing TJLB.

Pilot Study of the Safety and Efficacy of Gallbladder Cryoablation in a Porcine Model: Midterm Results.

PURPOSE: To investigate the midterm safety and efficacy of computed tomography (CT)-guided percutaneous gallbladder cryoablation in swine. MATERIALS AND METHODS: Three swine underwent gallbladder cryoablation. Cryoprobes were positioned percutaneously at the gallbladder margins or within the gallbladder lumen under CT guidance. Two freeze/thaw cycles were performed. One animal was euthanized on postprocedure day 4 as a result of hematemesis unrelated to the ablation. The other 2 animals were euthanized at postprocedure days 30 and 48, respectively. The gallbladder and bile ducts were resected and examined microscopically. RESULTS: Gallbladder cryoablation was completed with freeze/thaw cycle durations of 7.5-10 minutes (mean, 9.4 min ± 1.3) and ablation margins of 5.8-11.5 mm (mean, 7.8 mm ± 1.9). No nontarget ablation was observed. Laboratory values at postprocedure day 4 and the time of euthanasia were within normal limits. Two of 3 animals thrived and exhibited appropriate activity and weight gain. Contrast-enhanced CT immediately before euthanasia demonstrated delayed linear enhancement of the gallbladder wall. Gross inspection at autopsy revealed fibrotic-appearing gallbladders. Cholecystography revealed no communication to the biliary tree. Histologic examination demonstrated complete gallbladder wall fibrosis. Autopsy of the animal euthanized on day 4 revealed a gastric mucosal ulcer distant from the ablation site with no gastric serosal injury. CONCLUSIONS: Gallbladder cryoablation is a promising alternative to surgical cholecystectomy, with complete transmural gallbladder wall fibrosis and cystic duct occlusion seen at 30 and 48 days in swine. Further studies are required to establish procedural safety and long-term efficacy.

Percutaneous embolization of post traumatic splenic pseudoaneurysm.

Management of splenic pseudoaneurysms in hemodynamically stable patients has shifted toward nonoperative management, including watchful waiting and endovascular embolization. Standard of treatment does not include percutaneous embolization for splenic pseudoaneurysm repair. In this case report, we document a successful percutaneous embolization of a post traumatic splenic pseudoaneurysm with thrombin. Percutaneous embolization of splenic pseudoaneurysms can be considered a viable technique in patients who fail endovascular embolization or have lesions inaccessible to endovascular repair.

Radiation Dose Reduction during Uterine Fibroid Embolization Using an Optimized Imaging Platform.

PURPOSE: To assess radiation dose reduction during uterine fibroid embolization (UFE) using an optimized angiographic processing and acquisition platform. MATERIALS AND METHODS: Radiation dose data for 70 women (mean age, 46 y; range, 34-67 y) who underwent UFE were retrospectively analyzed. Twenty-one patients underwent UFE using the baseline fluoroscopic and angiographic image acquisition platform, and 49 underwent UFE after implementing an optimized imaging platform in otherwise identical angiography suites. Cumulative kerma-area product (CKAP), cumulative air kerma (CAK), total fluoroscopy time, and image exposure number were collected for each procedure. Image quality was assessed by 3 interventional radiologists blinded to the platform used for image acquisition and processing. RESULTS: Patients undergoing UFE using the new x-ray fluoroscopy platform had significantly lower CKAP and CAK indicators than patients for whom baseline settings were used. Mean CKAP decreased by 60% from 438.5 Gy · cm2 (range, 180.3-1,081.1 Gy · cm2) to 175.2 Gy · cm2 (range, 47.1-757.0 Gy · cm2; P < .0001). Mean CAK decreased by 45% from 2,034.2 mGy (range, 699.3-5,056.0 mGy) to 1,109.8 mGy (range, 256.6-4,513.6 mGy; P = .001). No degradation of image quality was identified through qualitative evaluation. CONCLUSIONS: Significant reduction in patient radiation dose indicators can be achieved with use of an optimized image acquisition and processing platform.

CT-detected traumatic small artery extremity injuries: surgery, embolize, or watch? A 10-year experience.

Advances in computed tomography (CT) angiography have increased the sensitivity and specificity of detecting small branch arterial injuries in the extremities of trauma patients. However, it is unclear whether these patients should undergo surgery, angioembolization, or conservative watchful waiting. We hypothesized that uncomplicated small arterial branch injuries can be managed successfully with watchful waiting. A 10-year retrospective review of extremity CT angiograms with search findings of arterial "active extravasation" or "pseudoaneurysm" was performed at a level 1 county trauma center. Subgroup analysis was performed on those with isolated extremity injury and those with concurrent injuries. A total of 31 patients had CT-detected active extravasation (84 %) or pseudoaneurysm (16 %), 71 % of which were isolated vascular injuries. Of the patients evaluated, 71 % (n = 22) were managed with watchful waiting, 19 % (n = 6) with angioembolization, and 10 % (n = 3) with surgery. Watchful waiting complications included progression to alternative treatment (n = 1) and blood transfusions (n = 2). Complications of surgery included the inability to find active bleeding (n = 1) and postoperative psychosis (n = 1). Complications of angioembolization were limited to a postprocedure blood transfusion (n = 1). Patients with isolated vascular injuries had an average length of stay of 2.9 days, with management averages of the following: 2.7 days with watchful waiting (n = 16), 3.3 days with angioembolization (n = 3), and 3.7 days with surgery (n = 3). CT angiography has greatly increased the reported incidence of traumatic arterial injury in the extremity. We propose that small branch arterial injuries in the extremities can be managed successfully with watchful waiting and do not often require immediate embolization.

Bartonella quintana Aortitis in a Man with AIDS, Diagnosed by Needle Biopsy and 16S rRNA Gene Amplification.

A man with newly diagnosed AIDS presented with months of back pain and fever. Computed tomography (CT) results demonstrated aortitis with periaortic tissue thickening. DNA amplification of biopsy tissue revealed Bartonella quintana, and Bartonella serologies were subsequently noted to be positive. The patient improved with prolonged doxycycline and rifabutin treatment. This case illustrates how molecular techniques are increasingly important in diagnosing Bartonella infections.

Intraprocedural Safety and Technical Success of the MVP Micro Vascular Plug for Embolization of Pulmonary Arteriovenous Malformations.

This case series describes early experience, intraprocedural safety, and technical success of the MVP Micro Vascular Plug (MVP; Covidien, Irvine, California) for embolization of 20 pulmonary arteriovenous malformations (PAVMs) using 23 plugs in seven patients with hereditary hemorrhagic telangiectasia. There was no device migration, and all devices were successfully detached electrolytically. Immediate cessation of flow through the feeding artery was achieved in 21 of 23 (91%) deployments. There was one minor complication. This series demonstrates the MVP to be safe and technically successful in the treatment of PAVMs.

Periprocedural Patient Care.

Periprocedural care of patients who undergo image-guided interventions is a task of monumental importance. As physicians who perform procedures, radiologists rely on their noninterpretive skills to optimize patient care. At the center of periprocedural care is proper patient identification. It is imperative to perform the indicated procedure for the correct patient. It is also of great importance to discuss with the patient the nature of the procedure. This conversation should include the indications, risks, benefits, alternatives, and potential complications of the procedure. Once the patient agrees to the procedure and grants informed consent, it is imperative to stop and confirm that the correct procedure is being performed on the correct patient. This universal time-out policy helps decrease errors and improves patient care. To optimize our interpretative and procedural skills, it may be necessary to provide the patient with sedation or anesthesia. However, it is important to understand the continuum of sedation and be able to appropriately monitor the patient and manage the sedation in these patients. To minimize the risks of infection, periprocedural care of patients relies on aseptic or, at times, sterile techniques. Before the procedure, it is important to evaluate the patient's coagulation parameters and bleeding risks and correct the coagulopathy, if needed. During the procedure, the patient's blood pressure and at times the patient's glucose levels will also require monitoring and management. After the procedure, patients must be observed in a recovery unit and deemed safe for discharge. The fundamental components of periprocedural care necessary to enhance patient safety, satisfaction, and care are reviewed to familiarize the reader with the important noninterpretive skills necessary to optimize periprocedural care.

Arterial Spin-Labeling MR Imaging in the Detection of Intracranial Arteriovenous Malformations in Patients with Hereditary Hemorrhagic Telangiectasia.

BACKGROUND AND PURPOSE: Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disease that causes vascular malformations in a variety of organs and tissues, including brain AVMs. Because brain AVMs have the potential to cause disabling or fatal intracranial hemorrhage, detection of these lesions before rupture is the goal of screening MR imaging/MRA examinations in patients with HHT. Prior studies have demonstrated superior sensitivity for HHT-related brain AVMs by using postcontrast MR imaging sequences as compared with MRA alone. We now present data regarding the incremental benefit of including arterial spin-labeling (ASL) perfusion sequences as part of MR imaging/MRA screening in patients with this condition. MATERIALS AND METHODS: We retrospectively analyzed 831 patients at the UCSF Hereditary Hemorrhagic Telangiectasia Center of Excellence. Of these, 42 patients had complete MR imaging/MRA, ASL perfusion scans, and criterion-standard DSA data. Two neuroradiologists reviewed imaging studies and a third provided adjudication when needed. RESULTS: Eight patients had no brain AVMs detected on DSA. The remaining 34 patients had 57 brain AVMs on DSA. Of the 57 identified AVMs, 51 (89.5%) were detected on ASL and 43 (75.4%) were detected on conventional MR imaging/MRA sequences (P = .049), with 8 lesions detected on ASL perfusion but not on conventional MR imaging. CONCLUSIONS: ASL provides increased sensitivity for brain AVMs in patients with HHT. Inclusion of ASL should be considered as part of comprehensive MR imaging/MRA screening protocols for institutions taking care of patients with HHT.