Ronald S. Winokur

Characterization of In Vivo Ablation Zones Following Percutaneous Microwave Ablation of the Liver with Two Commercially Available Devices: Are Manufacturer Published Reference Values Useful?

PURPOSE To analyze in vivo ablation properties of microwave ablation antennae in tumor-bearing human livers by performing retrospective analysis of ablation zones following treatment with two microwave ablation systems. MATERIALS AND METHODS Percutaneous microwave ablations performed in the liver between February 2011 and February 2013 with use of the AMICA and Certus PR ablation antennae were included. Immediate postablation computed tomography images were evaluated retrospectively for ablation length, diameter, and volume. Ablation length, diameter, and volume indices were calculated and compared between in vivo results and references provided from each device manufacturer. The two microwave antenna models were then also compared versus each other. RESULTS Twenty-five ablations were performed in 20 patients with the AMICA antenna, and 11 ablations were performed in eight patients with the Certus PR antenna. The AMICA and Certus PR antennae showed significant differences in ablation length (P = .013 and P = .009), diameter (P = .001 and P = .009), and volume (P = .003 and P = .009). The AMICA ablation indices were significantly higher than the Certus PR ablation indices in length (P = .026) and volume (P = .002), but there was no significant difference in ablation diameter indices (P = .110). CONCLUSIONS In vivo ablation indices of human tumors are significantly smaller than reference ex vivo ablation indices, and there are significant differences in ablation indices and sphericity between devices.

Recurrence patterns after endovenous laser treatment of saphenous vein reflux.

Introduction The patterns of recurrent varicose veins after endovascular ablation of the saphenous veins are not well described. Methods The current study describes the ultrasound defined recurrence patterns seen in 58 patients (79 limbs) who returned for evaluation of recurrent varicose veins from a cohort of 802 patients treated with endovenous laser ablation and subsequent sclerotherapy from March 2000 to March 2007 with clinical follow-up until May 2014. Findings The most common ultrasound defined recurrence patterns leading to the varicose veins were new reflux in the anterior accessory saphenous and small saphenous veins as well as recanalization of the treated saphenous segment. Neovascularization at the saphenofemoral junction and incompetent perforating veins as the source of the recurrent veins were not seen. Conclusions The patterns of recurrence following thermal ablation of saphenous veins are different to those seen after surgery. Specifically, new reflux in other saphenous veins is responsible for most recurrent varicose veins and neovascularity seems to be unusual following endovenous laser ablation.

Venous Access Site Closures Using the VASCADE Vascular Closure System

This single-center, retrospective study describes using the VASCADE Vascular Closure System (Cardiva Medical, Inc, Santa Clara, California) to close 32 venous access sites in 21 consecutive patients (11 females; 10 males; age 45 y ± 19) after catheter-directed interventions. Sheath sizes were 5-10 F (8.7 F ± 1.7). Hemostasis was achieved in 30 of 32 deployments (93.8%). Complications were observed after 6 of 32 procedures, including 5 minor events in 4 patients and 1 major event in 1 patient which was likely unrelated to device deployment. The VASCADE device efficaciously closes venotomies after deep venous procedures, but further studies comparing it with manual compression are required to define its optimal use.

Transjugular liver access cannula as a guiding instrument for the recanalization of chronic venous occlusions.

BACKGROUND Chronic venous occlusions can result in debilitating symptoms and can be refractory to standard methods of venous recanalization because of the formation of dense fibrous tissue. A transjugular liver access cannula can be incorporated into recanalization efforts to treat such refractory cases. This report describes our experience using the transjugular liver access cannula technique in nine patients. METHODS A review of patients requiring venous recanalization between May 2012 and October 2014 identified nine cases that required the use of a transjugular liver access cannula as a guiding instrument. Lesion characteristics, technical success, and clinical outcomes were evaluated. RESULTS The transjugular liver access cannula was used to traverse a total of nine chronic occlusions in both the upper and lower central venous systems in nine patients. The technical success rate was 100%. There were no clinically significant complications. One patient was lost to follow-up. Of the remaining eight patients, seven experienced symptomatic relief within 1 month of recanalization. CONCLUSIONS The transjugular liver access cannula may serve as a useful adjunctive tool during difficult venous recanalizations, especially when traditional guidewire and catheter techniques fail.

Standardized Reporting in IR: A Prospective Multi-Institutional Pilot Study

PURPOSE To assess adoption and survey-based satisfaction rates following deployment of standardized interventional radiology (IR) procedure reports across multiple institutions. MATERIALS AND METHODS Standardized reporting templates for 5 common interventional procedures (central venous access, inferior vena cava [IVC] filter insertion, IVC filter removal, uterine artery embolization, and vertebral augmentation) were distributed to 20 IR practices in a prospective quality-improvement study. Participating sites edited the reports according to institutional preferences and deployed them for a 1-year pilot study concluding in July 2015. Study compliance was measured by sampling 20 reports of each procedure type at each institution, and surveys of interventionalists and referring physicians were performed. Modifications to the standardized reporting templates at each site were analyzed. RESULTS Ten institutions deployed the standardized reports, with 8 achieving deployment of 3-12 months. The mean report usage rate was 57%. Each site modified the original reports, with 26% mean reduction in length, 18% mean reduction in wordiness, and 60% mean reduction in the number of forced fill-in fields requiring user input. Linear-regression analysis revealed that reduced number of forced fill-in fields correlated significantly with increased usage rate (R2 = 0.444; P = .05). Surveys revealed high satisfaction rates among referring physicians but lower satisfaction rates among interventional radiologists. CONCLUSIONS Standardized report adoption rates increased when reports were simplified by reducing the number of forced fill-in fields. Referring physicians preferred the standardized reports, whereas interventional radiologists preferred standard narrative reports.

Interventional Radiologic Techniques for Screening, Diagnosis and Treatment of Patients with Renal Artery Stenosis

Renal artery stenosis resulting in renovascular hypertension or renal ischemia is a potentially treatable condition that results in increased morbidity and mortality, especially among older individuals. Sophisticated imaging techniques are used for screening and identification of affected patients to guide therapy. Treatment guidelines recommend intervention in patients with significant renal artery stenosis, although recent evidence has questioned the benefit of intervention in certain populations. Current research focuses on improving the specificity of imaging techniques and determining which imaging modalities best identify patients who will benefit from intervention.

Radiology Research in Quality and Safety: Current Trends and Future Needs

Promoting quality and safety research is now essential for radiology as reimbursement is increasingly tied to measures of quality, patient safety, efficiency, and appropriateness of imaging. This article provides an overview of key features necessary to promote successful quality improvement efforts in radiology. Emphasis is given to current trends and future opportunities for directing research. Establishing and maintaining a culture of safety is paramount to organizations wishing to improve patient care. The correct culture must be in place to support quality initiatives and create accountability for patient care. Focused educational curricula are necessary to teach quality and safety-related skills and behaviors to trainees, staff members, and physicians. The increasingly complex healthcare landscape requires that organizations build effective data infrastructures to support quality and safety research. Incident reporting systems designed specifically for medical imaging will benefit quality improvement initiatives by identifying and learning from system errors, enhancing knowledge about safety, and creating safer systems through the implementation of standardized practices and standards. Finally, validated performance measures must be developed to accurately reflect the value of the care we provide for our patients and referring providers. Common metrics used in radiology are reviewed with focus on current and future opportunities for investigation.

Use of the VASCADE Arterial Closure Device to Achieve Hemostasis after a Deep Venous Procedure.

Editor: Although vascular closure devices are frequently used to seal arterial access sites after endovascular procedures, their use in deep venous procedures is less common. We describe the successful use of the VASCADE Vascular Closure System (VASCADE; Cardiva Medical, Inc, Sunnyvale, California) to seal 7-F and 10-F venous access sites in a patient undergoing deep venous stent placement. The VASCADE vascular closure device places a biodegradable collagen plug outside the vessel. It is indicated for closure of a femoral arterial access site after placement of a 5-F to 7-F sheath. The device is inserted through the vascular sheath. When the unformed radiopaque nitinol disc is beyond the tip of the sheath, it is deployed, and the apparatus along with the sheath is pulled back toward the access site. When the disc is secured against the inner wall of the vessel, the sheath is removed from the tissue tract over the device. The collagen plug is exposed in the tract and is kept extravascular by the intravascular disc. The collagen plug expands as it encounters fluid and blood, inducing hemostasis. Thereafter, the disc is collapsed and removed with the catheter leaving behind only the reabsorbable collagen plug. Compared with manual compression, use of the VASCADE device has demonstrated a significant reduction in time to hemostasis, time to ambulation, and time to discharge eligibility when used to seal arteries (1). Also, minor complications such as bleeding and thrombosis are less frequent. However, there are no reports of its successful use in the deep venous system. This report is exempt from institutional review board approval. A 59-year-old man with a history of multiple venous thromboembolic events presented with acute left lower extremity swelling in April 2015. In 2008, an inferior vena cava filter was placed after postoperative development of deep vein thrombosis. In 2013, he was treated for caval and bilateral iliac thrombosis with

Superficial Veins: Treatment Options and Techniques for Saphenous Veins, Perforators, and Tributary Veins

Superficial venous insufficiency is a common cause of lower-extremity symptoms of pain and swelling. A thorough understanding of the superficial venous anatomy, as well as gaining knowledge of treatment approaches, can direct ones approach to providing an appropriate treatment for desired and durable outcomes. This article reviews the details of anatomy and treatment of the saphenous veins, perforator veins, and tributary veins.

Patient Assessment: Clinical Presentation, Imaging Diagnosis, Risk Stratification, and the Role of Pulmonary Embolism Response Team

Pulmonary embolism (PE) is currently the third leading cause of death and moreover is likely underdiagnosed. PE remains the most common preventable cause of hospital deaths in the United States, which may be attributable to its diagnostic challenges. Although difficult to diagnose, patient mortality rates are time-dependent, and thus, the suspicion and diagnosis of PE in a timely manner is imperative. Diagnosis based on several criteria which may dictate imaging workup as well as laboratory tests and clinical parameters are discussed. The evolution of treatment guidelines via various clinical trials and recommendations is outlined, setting the stage for the use of fibrinolytics, whether systemic or catheter directed. Treatment, including fibrinolytics, is predicated on patient triage into three large categories-massive, submassive, or low-risk PE. Additionally, a relatively new concept of a multidisciplinary team composed of several subspecialty experts known as the PE response team (PERT) is discussed. PERTs timely and unified recommendations have been shown to optimize care and decrease mortality while tailoring treatment to each individual afflicted by PE.