Robert Torrance Andrews

• Doctor of Medicine
• University of California, Davis

Interventional radiology (IR) practices take many forms, but often are distinguished as following either an academic or private practice model. Both differences and similarities are seen when comparing these two general practice categories, and often the line between the two models is unclear. This article reviews some of the commonalities and diff...

This chapter outlines many practical considerations involved in a pediatric IR service: the interventional suite itself, the delivery of a pediatric IR service and program, and the operation of a pediatric IR clinic. The next chapter will outline various clinical aspects of care during the pre-, intra-, and post-procedure phases. Inevitably there w...

This chapter focuses on the clinical aspects of delivery of patient care, from periprocedural assessment to discharge. Practices will vary from institution to institution so several different approaches and options are presented in this chapter. Many examples from pediatric interventional radiology (PIR), drawn from the authors’ experience, are int...

To report the initial experience of a pediatric center's use of expanded polytetrafluoroethylene (ePTFE) endografts for the creation of transjugular intrahepatic portosystemic shunts (TIPSs) in children. Twelve consecutive patients had a TIPS created, all with ePTFE endografts. Nine were children younger than 18 years of age: one infant (age 18 mo)...

The committee came to the general consensus that the mechanisms for evaluating patients with MS for jugular and azygous venous compromise and the value of treating these lesions with angioplasty warrant careful, well designed additional study. The committee believed the specific parameters needed for a large-scale, pivotal multicenter trial were no...

The feasibility of video-assisted retroperitoneal debridement (VARD) for infected pancreatic walled-off necrosis is established. We provide prospective data on the safety and efficacy of VARD. Multicenter, prospective, single-arm phase 2 study. Six academic medical centers. We evaluated 40 patients with pancreatic necrosis who had infection determi...

This article outlines general concepts of, and strategies for, therapeutic embolization throughout the body, touching on all major arterial distributions. Clinical scenarios that allow or prevent safe embolization of vessels are presented. Specific agents are recommended where appropriate, as are alternate approaches when embolization is not an opt...

Leiomyomas (or fibroids) are exceedingly common lesions. The indications to initiate treatment are based on the symptoms that can arise from their presence. In general, medical therapy should be considered the first line of treatment. Currently, the treatment of fibroids is in evolution. Since uterine artery embolization (UAE) was first described b...

A patient underwent radiofrequency (RF) ablation of a pleural-based pulmonary metastasis from treated hepatocellular carcinoma. Ten months after the procedure, computed tomography and positron emission tomography findings raised the concern of tumor recurrence with invasion of the chest wall, for which the patient underwent thoracotomy with resecti...

The purpose of this study was to evaluate the technical feasibility of ultrasound-based elastography as a tool for assessing the size and shape of the coagulation necrosis caused by radio frequency ablation (RFA) probes using expandable electrodes ex vivo as well as in a patient with a liver metastasis. A commercially available expandable RFA probe...

Inferior vena cava (IVC) filtration is commonly performed to protect against pulmonary embolism in acutely injured patients with contraindications for anticoagulation therapy. Increasingly, optionally retrievable IVC filters are utilized, particularly in younger patients with longer life expectancies. There are well-described anatomical variants th...

A multidisciplinary VTE Research Consensus Panel was convened to develop a prioritized research agenda for the use of endovascular techniques to treat VTE. The Panel recommended the development of a prospective randomized trial to compare endovascular thrombus removal with anticoagulant therapy for the first-line treatment of acute proximal DVT. Ac...

The authors present their experience in treating congenital venous malformations with ultrasound (US)-guided endovenous diode laser. Six patients underwent treatment of eight venous malformations for complaints including pain, activity limitation, or cosmetic defect. At a mean follow-up interval of 14.5 months, all had either resolution of (five pa...

The present study evaluates the short- and midterm efficacy of a small intestinal submucosa (SIS) device for fallopian tube occlusion in rabbits. In a pilot study, several SIS device designs were tested for positional stability (absence of migration). The design selected for further testing consisted of a center of spongy SIS surrounded by an SIS s...

At one time, direct intravascular contrast angiography was the standard method for confirmatory diagnosis of venous or pulmonary arterial thromboembolism. Although sensitive and specific, conventional catheter-based contrast imaging is invasive and associated with a risk of phlebitis and thrombosis. These procedures require specialized training and...

The aim of this study was to create an animal model of endoleak after stent-graft placement for abdominal aortic aneurysm (AAA) in which a large aneurysmal sac would be preserved for the testing of techniques for its percutaneous occlusion. Infrarenal AAAs were created in nine dogs by anastomosis of an isolated segment of the inferior vena cava to...

To determine whether two commonly used embolic agents have differing rates of blood flow reduction during transcatheter embolization of the renal arteries in an animal model. The renal arteries of 10 pigs were embolized with either polyvinyl alcohol (300-500 or 500-700- micro m) or tris-acryl gelatin microspheres (300-500 or 700-900- micro m). Equi...

To evaluate the components of commonly used central venous catheter kits with respect to the potential for guidewire-mediated complications during catheter placement.Prospective, nonrandomized, observational study. Six academic hospitals across the United States. None. None. 30 commercially manufactured catheter kits (15 tunneled, 15 nontunneled) w...

We describe a simple but underutilized technique for improving visualization during transcatheter embolization using particulate agents. The technique is of distinct utility in uterine fibroid embolization, during which non-target embolization can be of particular clinical significance.

The goal of this study was to evaluate the rabbit model for studies of particulate uterine artery embolization (UAE). Rabbits were chosen because it was believed that their year-round breeding time and short duration of pregnancy would be useful in studies of fertility and pregnancy after UAE. Bilateral UAE was performed in 12 adult female New Zeal...

Increasing clinical experience with uterine fibroid embolization (UFE) has improved the ability of interventionalist radiologists to discern who is and who is not an appropriate candidate for this procedure. Initial evaluation should be directed at obtaining answers to the following key questions: (1) Does the patient have uterine fibroids that acc...

Successful superselective catheterization of the uterine artery requires familiarity with female pelvic arterial anatomy, knowledge of effective catheter and guidewire combinations, and a few tricks. A learning curve can be expected for each of these elements, although it is assumed that the operator will already have experience in basic catheter t...

Conscious sedation and analgesia are integral components of successful uterine fibroid embolization (UFE), both in providing comfort to the anxious patient undergoing an elective procedure and for providing relief of the severe pelvic pain, cramps, and nausea that may result from acute uterine ischemia and the postembolization syndrome that may fol...

Fortunately, the number of complications reported after uterine fibroid embolization (UFE) is extremely low. Angiographic mishap or drug reaction are probably more common than purely UFE-related complications. However, the possibility of infection or necrosis of the uterus, with their significant attendant morbidity, is a sobering reminder that emb...

Building a uterine fibroid embolization (UFE) practice can be a complex process. Choices must be made regarding whether to align oneself with a gynecologist or to accept direct referrals. For the interventional radiologist, the responsibilities of evaluation and patient care pose unique and time-consuming administrative and clinical challenges. Phy...

Over the past decade, numerous technological advances have allowed computed tomography (CT) to assume an increasing role in vascular imaging. These innovations include volumetric (spiral) image acquisition and postprocessing techniques that present image data in various ways that facilitate clinical use. In addition, the speed of multidetector and...

To review the incidence of ovarian collateral supply to uterine fibroids as demonstrated by nonselective abdominal aortography before uterine artery embolization (UAE) and to evaluate the effect of such visualization on interventional management. The aortograms of 51 consecutive patients (mean age, 42.4 y; range, 30--53 y) undergoing UAE for sympto...

To evaluate the effects of catheter-directed thrombin in the peripheral arterial circulation of swine. Thrombin was injected into a single femoral artery in 20 domestic swine. Each of five animals from four dose groups received 50, 150, 250, or 1,000 U as a single dose. Bilateral femoral arterial flow was monitored for as long as 4 hours and evalua...

To investigate patient radiation exposures during uterine arterial embolization and the factors responsible for those exposures. Clinical and procedural factors were evaluated for 42 consecutive procedures performed in 39 patients by one operator. Seven patients were excluded because of early termination (n = 1) or unusual conditions that necessita...

This chapter provides a review of diagnostic angiography in the pelvis and lower extremities. Although intended primarily as a review of disease states and their angiographic manifestations, the chapter also briefly covers angiographic technique and both normal and common variant anatomy. Venous diseases are a minor topic in this chapter, but are d...

The introduction of excessive lengths of guidewire during placement of central venous catheters from the internal jugular vein (IJV) or the subclavian vein (SCV) can result in rare but significant complications. To identify a "safe" guidewire insertion length, the authors performed direct intravascular measurement of the distance from these venous...

To evaluate the potential benefits of placing a polytetrafluoroethylene (PTFE)-covered stent-graft during initial creation of a transjugular intrahepatic portosystemic shunt (TIPS) in clinical practice. De novo TIPS were created with a PTFE stent-graft in four male and four female patients with symptomatic portal hypertension awaiting liver transpl...

To investigate the effects of joint motion on the structural integrity of periarticular stents and on the development of neointimal hyperplasia within these devices. In four juvenile farm swine, Wall-stents were implanted in the common femoral arteries and contralateral common femoral veins, centered at the point of maximal conformational change du...

We present four patients in whom bedside placement of a central venous catheter was complicated by entrapment of a J-tip guidewire by a previously placed vena cava (VC) filter. Two Venatech filters were fragmented and displaced into the superior VC or brachiocephalic vein during attempted withdrawal of the entrapped wire. Two stainless-steel Greenf...

To determine the sensitivity, specificity, and charges associated with single-specimen bile cytologic study in patients with obstructive jaundice. Eighty consecutive patients with presumed malignant biliary strictures underwent percutaneous biliary drainage (PBD). Cytologic evaluation was performed on a single bile specimen from each patient collec...

Intravenous morphine sulfate increases hydrostatic pressure within the biliary tree, latrogenic increases in biliary pressure are commonly used to verify cystic duct obstruction during preoperative cholescintigraphy. Extravasation has occasionally been reported in cases of gallbladder necrosis or rupture. The present case demonstrates an additional...

To determine the influence of filter leg-interlocking on filtering efficiency of titanium Greenfield inferior vena cava filters in an in vitro model. Titanium Greenfield filters (TGF) were placed in an inferior vena cava (IVC) flow phantom with no interlocking legs, or with one or two pairs of legs interlocked. Clot emboli of varying sizes were int...

Thesis (M.D.)--University of California, San Diego, 1990. Includes bibliographical references. No. 1. Peripheral vision suppression of melatonin / Joshua S. Adler, Daniel F. Kripke, Sarah L. Berga -- no. 2. Measurement of conformational changes associated with active transport by the (Na, K)--ATPase with resonance energy transfer between site speci...