Search

Diverticulosis remains the commonest cause for acute lower gastrointestinal tract bleeding (GIB). Conservative management is initially sufficient for most patients, followed by elective diagnostic tests. However, if acute lower GIB persists, it can be investigated with colonoscopy, CT angiography (CTA), or red blood cell (RBC) scan. Colonoscopy can identify the site and cause of bleeding and provide effective treatment. CTA is a noninvasive diagnostic tool that is better tolerated by patients, can identify actively bleeding site or a potential bleeding lesion in vast majority of patients. RBC scan can identify intermittent bleeding, and with single-photon emission computed tomography, can more accurately localize it to a small segment of bowel. If patients are hemodynamically unstable, CTA and transcatheter arteriography/embolization can be performed. Colonoscopy can also be considered in these patients if rapid bowel preparation is feasible. Transcatheter arteriography has a low rate of major complications; however, targeted transcatheter embolization is only feasible if extravasation is seen, which is more likely in hemodynamically unstable patients. If bleeding site has been previously localized but the intervention by colonoscopy and transcatheter embolization have failed to achieve hemostasis, surgery may be required. Among patients with obscure (nonlocalized) recurrent bleeding, capsule endoscopy and CT enterography can be considered to identify culprit mucosal lesion(s). The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Iliofemoral venous thrombosis carries a high risk for pulmonary embolism, recurrent deep vein thrombosis, and post-thrombotic syndrome complicating 30% to 71% of those affected. The clinical scenarios in which iliofemoral venous thrombosis is managed may be diverse, presenting a challenge to identify optimum therapy tailored to each situation. Goals for management include preventing morbidity from venous occlusive disease, and morbidity and mortality from pulmonary embolism. Anticoagulation remains the standard of care for iliofemoral venous thrombosis, although a role for more aggressive therapies with catheter-based interventions or surgery exists in select circumstances. Results from recent prospective trials have improved patient selection guidelines for more aggressive therapies, and have also demonstrated a lack of efficacy for certain conservative therapies. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Venous thromboembolism (VTE)—deep vein thrombosis and pulmonary embolism—is a common cause of morbidity and mortality. The mainstay of VTE prophylaxis and therapy is anticoagulation. In select patients with VTE, inferior vena cava (IVC) filters are used to prevent pulmonary embolism by trapping emboli as they pass from the lower extremity venous system through the IVC. These guidelines review the indications for placement of IVC filters in acute and chronic VTE, as well as the indications for retrieval of implanted IVC filters. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Social media is a ubiquitous part of society and used by many healthcare professionals, including radiologists. This article prepared by the 2019-2020 Radiology Research Alliance Social Media Task Force presents different uses and benefits of an online professional social media profile. Physician and healthcare-specific issues along with popular platforms such as LinkedIn, Facebook, Twitter, Instagram, and YouTube are used to explore topics including education, branding, research, mentorship, promotion, and leadership.

The oncological impact of surgical complications has been studied in visceral and pancreatic cancer.To investigate the impact of complications on tumour recurrence after resections for pancreatic neuroendocrine tumours.We have retrospectively analysed 105 consecutive resections performed at the Royal Free London Hospital from 1998 to 2014, and studied the long-term outcome of nil-minor (3) versus major (≥3) Clavien-Dindo complications (CD) on disease-free (DFS) and overall survival (OS).The series accounted for 41 (39%) pancreaticoduodenectomies, two (1.9%) central, 48 (45.7%) distal pancreatectomies, eight (7.6%) enucleations, four (3.8%) total pancreatectomies. Sixteen (15.2%) were extended to adjacent organs, 13 (12.3%) to minor liver resections. Postoperative complications presented in 43 (40.1%) patients; CD grade 1 or 2 in 23 (21.9%), grades ≥3 in 20 (19%). Among 25 (23.8%) pancreatic fistulas, 14 (13.3%) were grades B or C. Thirty-four (32.4%) patients developed exocrine, and 31 (29.5%) endocrine insufficiency. Seven patients died during a median 27 (0-175) months follow up. Thirty-day mortality was 0.9%. OS was 94.1% at 5 years. Thirty tumours recurred within 11.7 (0.8-141.5) months. DFS was 44% at 5 years. At univariate analysis, high-grade complications were not associated with shorter DFS (p = 0.744). At multivariate analysis, no parameter was independent predictor for DFS or OS. The comparison of nil-minor versus major complications showed no DFS difference (p = 0.253).From our series, major complications after P-NETs resection are not associated to different disease recurrence; hence do not require different follow up or adjuvant regimens.

Obtaining central venous access is one of the most commonly performed procedures in hospital settings. Multiple devices such as peripherally inserted central venous catheters, tunneled central venous catheters (eg, Hohn catheter, Hickman catheter, C. R. Bard, Inc, Salt Lake City UT), and implantable ports are available for this purpose. The device selected for central venous access depends on the clinical indication, duration of the treatment, and associated comorbidities. It is important for health care providers to familiarize themselves with the types of central venous catheters available, including information about their indications, contraindications, and potential complications, especially the management of catheters in the setting of catheter-related bloodstream infections. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Iliac artery occlusive disease can present as a sudden-onset acute thrombotic or thromboembolic event or as a chronic progressive atherosclerotic process that presents as claudication progressing to rest pain. Depending on the clinical presentation, the diagnosis is usually confirmed through Doppler vascular ultrasound, CT angiography, or MR angiography; the choice of imaging is usually based on modality availability and the presence of patient comorbidities such as chronic kidney disease. The Trans-Atlantic Inter-Society Consensus II classification system is commonly used to describe the extent of the peripheral vascular disease. Depending on the pathophysiology, clinical presentation, and radiologic extent of the disease process, therapeutic options for acute thrombotic cases can include supportive care, anticoagulation, thrombolytic therapy, surgical or catheter-directed mechanical thrombectomy, and surgical bypass. Therapeutic options for atherosclerotic disease include supportive measures such as behavior modification, a supervised exercise program, adjunctive treatment with anticoagulation and antiplatelet medications, angioplasty, stent placement, stent-graft placement, surgical or catheter-directed endarterectomy or plaque excision, and surgical bypass. This document describes the appropriateness of imaging in this patient population, treatment procedures for specific clinical scenarios, and the likely prognosis for these patients. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

This retrospective study presents three consecutive patients who underwent bilateral ureteral occlusion using the Amplatzer vascular plugs and N-butyl cyanoacrylate glue sandwich method. The patients were 63- and 65-year-old males and a 79-year-old female. Indications for the procedure included severe cystitis and complex vesicular fistulas unresponsive to urinary diversion. All three patients had immediate resolution of urinary leakage, resulting in symptom relief throughout the follow-up period. There were no procedure-related complications or side effects.

As the population of the United States grows increasingly diverse, health care disparities become vital to understand and mitigate. The ethical and financial implications of how groups of Americans gain access to health care have evolved into some of today's most challenging socioeconomic problems. Educators in radiology are just beginning to tackle the concepts of health care disparities, unconscious bias, and cultural competency. In July 2017, the Accreditation Council for Graduate Medical Education required that all trainees and teaching faculty of accredited training programs receive training and experience in new areas of quality improvement to include an understanding of health care disparities as part of the core competencies. To our knowledge, there is no centralized curriculum regarding health care disparities for radiology residents and fellows. Many programs, in fact, have yet to introduce the concept to their trainees, who may have difficulty recognizing that this is even a problem affecting radiology. This manuscript serves as a primer for radiology trainees on health care disparities, with the goal of defining major concepts and providing examples of how variable access to radiological care can have substantial impact on patient outcomes.

Obtaining central venous access is one of the most commonly performed procedures in hospital settings. Multiple devices such as peripherally inserted central venous catheters, tunneled central venous catheters (eg, Hohn catheter, Hickman catheter, C. R. Bard, Inc, Salt Lake City UT), and implantable ports are available for this purpose. The device selected for central venous access depends on the clinical indication, duration of the treatment, and associated comorbidities. It is important for health care providers to familiarize themselves with the types of central venous catheters available, including information about their indications, contraindications, and potential complications, especially the management of catheters in the setting of catheter-related bloodstream infections. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Iliac artery occlusive disease can present as a sudden-onset acute thrombotic or thromboembolic event or as a chronic progressive atherosclerotic process that presents as claudication progressing to rest pain. Depending on the clinical presentation, the diagnosis is usually confirmed through Doppler vascular ultrasound, CT angiography, or MR angiography; the choice of imaging is usually based on modality availability and the presence of patient comorbidities such as chronic kidney disease. The Trans-Atlantic Inter-Society Consensus II classification system is commonly used to describe the extent of the peripheral vascular disease. Depending on the pathophysiology, clinical presentation, and radiologic extent of the disease process, therapeutic options for acute thrombotic cases can include supportive care, anticoagulation, thrombolytic therapy, surgical or catheter-directed mechanical thrombectomy, and surgical bypass. Therapeutic options for atherosclerotic disease include supportive measures such as behavior modification, a supervised exercise program, adjunctive treatment with anticoagulation and antiplatelet medications, angioplasty, stent placement, stent-graft placement, surgical or catheter-directed endarterectomy or plaque excision, and surgical bypass. This document describes the appropriateness of imaging in this patient population, treatment procedures for specific clinical scenarios, and the likely prognosis for these patients. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

a Department of Gastroenterology, Beaujon Hospital, Clichy , France; b Department of Digestive and Liver Disease, Ospedale S. Andrea, Rome , Italy; c Department of Hepatology and Gastroenterology, CHU Bichat – B. Claude Bernard University, Paris , France; d Department of Pathology, Kantonsspital Baden , Switzerland; e Department of Gastroenterology, Massachussetts General Hospital, Boston , Mass. , USA; f B. Kos-Kudla, Department of Endocrinology, Slaska University, Zabrze , Poland; g Department of Surgery, UFR Bichat-Beaujon-Louis Mourier Hospital, Colombes , France; h Department of Oncology, Royal Free University, London , UK; i Department of Gastroenterology, Philipps University, Marburg , Germany; j Department of Surgery, Gothenburg University, Gothenburg , Sweden; k Department of Nuclear Medicine, Catholique de Louvain University, Brussels , Belgium; l Department of Nuclear Medicine, Erasmus MC University, Rotterdam , The Netherlands; m Department of Pathology and Laboratory Medicine, Universita degli Studi, Parma , Italy

Introduction Non-invasive imaging studies can provide visualization of allograft perfusion in the postoperative evaluation of newly transplanted renal allografts. Aim The purpose of our study was to evaluate the significance of elevated renal artery velocities in the immediate postoperative period. Methods Peak systolic velocities (PSVs) were obtained in the transplanted renal artery of 128 patients immediately after transplantation. Repeat allograft Doppler ultrasonography was performed on patients with elevated values. Results Of the 128 patients, 57 (44.5%) had severely elevated Doppler velocities >400 cm/s on the initial studies. Three patients within this category had persistently elevated values of >400 cm/s, warranting angiographic visualization of the renal vessels. Stent placement within the transplanted renal artery was required in two of these patients. There was normalization of the PSV in the remaining patients. Conclusions Routine allograft Doppler ultrasonography in the immediate postoperative period allows for visualization of allograft perfusion. Elevated renal artery velocities in the immediate postoperative period do not necessarily represent stenosis requiring intervention. Failure of the PSV to normalize may require further intervention, and angiography continues to be the gold standard.

Objectives To assess SAPE as an alternative treatment option in patients with refractory hematuria of prostatic origin. Methods A retrospective analysis of charts from 10 patients. Two patients were excluded from the analysis because of severe atherosclerotic disease that prevented selective angiography of the pelvic vasculature. Therefore, 8 patients, mean age of 78.3 ± 7.1 years with a history of refractory hematuria of prostatic origin were analyzed. All patients failed conventional therapy. The selective embolization procedures were performed between 2000 and 2006. Success was monitored with postembolization angiography and cessation of hematuria clinically. Results Of the 8 patients, 6 had a history of adenocarcinoma of the prostate (mean Gleason Grade 7, range 5 to 9); 4 were previously treated with external beam radiation. The remaining patient’s histories were consistent with benign prostatic hypertrophy. SAPE was technically successful in all 8 patients and resulted in immediate cessation of gross hematuria. Mean follow-up postembolization was 20.0 months (range 1.5 to 86.3 months). One patient had gross hematuria develop 14 months after embolization that was attributed to a bladder tumor recurrence. One patient with T4 prostate cancer had a rectovesical fistula develop 1 month after embolization. Conclusions SAPE results in cessation of refractory gross hematuria in patients with benign prostate hyperplasia and patients with prostate cancer previously treated with radiotherapy. SAPE may be considered an effective treatment for gross hematuria in patients with refractory hematuria regardless of the cause (radiation, cancer and/or hyperplasia).

Background: Cryoablation is an increasingly utilized treatment for renal-cell carcinoma. We describe the first reported case of colorenal fistula resulting from percutaneous renal cryoablation. Case Report: A 63-year-old man with hematuria was found to have an enhancing renal mass that was treated with percutaneous CT-guided cryoablation. Two months later, he presented with lower urinary-tract symptoms, and CT imaging revealed a colorenal fistula at the ablation site. Ureteral stent placement resulted in resolution of the fistula. Conclusions: Contrary to previously reported animal and clinical studies, our case report demonstrates that it is possible to incur serious harm to the renal collecting system as a result of percutaneous renal cryoablation. In stable patients, an attempt at conservative management of a fistula should precede extensive reconstructive efforts.

Background: The value of surgical resection in the management of pancreatic neuroendocrine tumors (PNET) with liver metastases (LM) is still debated. The aim of this study was to evaluate the outcomes of surgery of PNET with LM. Methods: Patients with PNET with synchronous LM between 2000 and 2011 from 4 high-volume institutions were included. The patients were divided into 3 groups: curative resection, palliative resection, and no resection. Results: Overall, 166 patients were included. Eighteen patients (11%) underwent curative resection, 73 patients (43%) underwent palliative resection, and 75 patients (46%) underwent conservative treatment. The median overall survival (OS) from the time of diagnosis was 73 months. Patients who underwent curative resection had a significantly better median OS from the initial diagnosis compared with those who underwent palliative resection and those who were conservatively treated (97 vs. 89 vs. 36 months, p = 0.0001). The median OS from the time of diagnosis in those patients who underwent radical or palliative resection was 97 months, with a 5-year survival rate of 76%. On multivariate analysis, factors associated with OS from the time of diagnosis were the presence of bilobar metastases, tumor grading, and curative resection in a first model. On a second model, curative or palliative surgery was an independent predictor of OS. Among 91 patients who underwent surgery, the presence of pancreatic neuroendocrine carcinoma G3 was the only factor independently associated with a poorer survival after surgery (median OS: 35 vs. 97 months, p < 0.0001). Conclusions: Patients with LM from PNET benefit from surgical resection, although surgery should be reserved to well- or moderately differentiated forms.

ENETS Consensus Guidelines for the management of patients with digestive neuroendocrine neoplasms : colorectal neuroendocrine neoplasms

The gain–bandwidth product of a practical junction circulator is fixed by the quality factor of its junction and the topology of its matching circuit. One difficulty with the design of a large mean power circulator or a millimetre one is that its quality factor may not be compatible with the use of 30° and 90° UEs. A method of overcoming these difficulties is to employ a 180° UE at each so-called characteristic plane of the junction. The purpose of the paper is to describe one arrangement in a WR75 waveguide. The device has a return loss of 20 dB and an insertion loss of 0.17 dB over a 16% frequency band. The quality factor of its complex gyrator circuit is 4.0.

To develop a new adverse event (AE) classification for the interventional radiology (IR) procedures and evaluate its clinical, research, and educational value compared with the existing Society of Interventional Radiology (SIR) classification via an SIR member survey.A new AE classification was developed by members of the Standards of Practice Committee of the SIR. Subsequently, a survey was created by a group of 18 members from the SIR Standards of Practice Committee and Service Lines. Twelve clinical AE case scenarios were generated that encompassed a broad spectrum of IR procedures and potential AEs. Survey questions were designed to evaluate the following domains: educational and research values, accountability for intraprocedural challenges, consistency of AE reporting, unambiguity, and potential for incorporation into existing quality-assurance framework. For each AE scenario, the survey participants were instructed to answer questions about the proposed and existing SIR classifications. SIR members were invited via online survey links, and 68 members participated among 140 surveyed. Answers on new and existing classifications were evaluated and compared statistically. Overall comparison between the two surveys was performed by generalized linear modeling.The proposed AE classification received superior evaluations in terms of consistency of reporting (P.05) and potential for incorporation into existing quality-assurance framework (P.05). Respondents gave a higher overall rating to the educational and research value of the new compared with the existing classification (P.05).This study proposed an AE classification system that outperformed the existing SIR classification in the studied domains.

John J. Crowley, MB, Mark J. Hogan, MD, Richard B. Towbin, MD, Wael E. Saad, MD,Kevin M. Baskin, MD, Anne Marie Cahill, MD, Drew M. Caplin, MD, Bairbre L. Connolly, MB,Sanjeeva P. Kalva, MD, Venkataramu Krishnamurthy, MD, Francis E. Marshalleck, MD,Derek J. Roebuck, MD, Nael E. Saad, MD, Gloria M. Salazar, MD, Leann S. Stokes, MD,Michael J. Temple, MD, T. Gregory Walker, MD, and Boris Nikolic, MD, MBA,for the Society of Interventional Radiology Standards of Practice Committee andthe Society for Pediatric Radiology Interventional Radiology Committee

PREAMBLE The membership of the Society of Interventional Radiology (SIR) Standards of Practice Committee represents experts in a broad spectrum of interventional procedures from the private and academic sectors of medicine. Generally, Standards of Practice Committee member dedicate the vast majority of their professional time to performing interventional procedures; as such, they represent a valid, broad expert constituency of the subject matter under consideration for standards production.

Prostatic artery embolization (PAE) is a promising new treatment for lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH). It has therefore garnered much interest in the interventional community. This article will review the scientific background for this therapy, describe the current devices available for treatment, and state the position of the Society of Interventional Radiology (SIR) with regard to the study and potential adoption of this therapy.

a Department of Gastroenterology, North Hampshire Hospital, Basingstoke , UK; b Stadtisches Klinikum Neuss, Lukaskrankenhaus, Chirurgische Klinik I, Neuss , Germany; c Istituto di Radiologia, Policlinco GB Rossi, Verona , Italy; d Institute for Pathology, Kantonsspital, Baden , Switzerland; e Departments of Internal Medicine and Endocrinological and Metabolic Sciences, University of Genoa, Genoa , Italy; f II. Internal Medical Department, University Hospital Martin, Martin , Slovakia; g G. Genimatas Hospital, Athens , Greece; h Erciyes University Medical School, Department of Endocrinology and Metabolism, Kayseri , Turkey; i H. Lee Moffitt Cancer Center/ University of South Florida, Tampa, Fla. , USA; j Anatomie Pathologique, Hopital Edouard Herriot, Lyon , France

a Digestive Diseases Branch, NIH, Bethesda, Md. , USA; b Division of General Surgery, Department of Surgery, Medical University of Vienna, Vienna , Austria; c Department of Hepatology and Gastroenterology, CHV A Pare Hospital, Boulogne , France; d Department of Gastroenterology, North Hampshire Hospital, Hampshire , UK; e Department of Surgery, Vivantes Humboldt Hospital, Berlin , Germany; f Department of Radiology, Royal Marsden Hospital, Sutton , UK; g Department of Pathology, Verona University, Verona , Italy; h Department of Radiology, Uppsala University, Uppsala , Sweden; i Department of Pathology, Universitatsspital Zurich, Zurich , Switzerland; j Department of Endocrinology and Metabolism, Hadassah University, Jerusalem , Israel; k Department of Oncology, Alexander Fleming Institute, Buenos Aires , Argentina; l Laboratory of Molecular Imaging and Experimental Radiotherapy, Universite Catholique de Louvain, Brussels , Belgium; m Department of Pathology, University Hospital of Kiel, Kiel , Germany

We report our experience with an embolization technique that allows safe, controllable exclusion of pulmonary arteriovenous malformations using detachable coils, a single venous access site, coaxial catheter guidance, and 1 or 2 microcatheters. This technique is particularly useful when treating central lesions with a short feeding artery and when high flow increases the risk of coil migration and nontarget embolization. It affords precise placement and repositioning of coils prior to detachment. The technique facilitates safe and successful endovascular closure of these challenging lesions.

Objective To describe a technique for image-guided percutaneous insertion of peritoneal ports in patients without ascites who have undergone surgical debulking for stage III ovarian cancer. Materials and Methods Between 2006 and 2010, 29 intraperitoneal ports were placed percutaneously in 29 patients who presented after debulking surgery for stage III ovarian cancer. Ultrasound and fluoroscopy guidance were used to assist in the port placement. Results We demonstrated a technical success rate of 100% in 29 patients. The ports remained in place for an average of 186 days; and during that time, only 2 complications (6.9%) arose. One patient presented with kinking and looping of the catheter/port reservoir connection, and the redundant loop was removed. The other patient presented with a suspected wound infection over the port pocket, and the port was removed. Conclusions Placement of percutaneous intraperitoneal ports is feasible with an acceptably low complication rate of 6.9% in patients without abdominal ascites.

i PREAMBLE The membership of the Society of Interventional Radiology (SIR) Standards of Practice Committee represents experts in a broad spectrum of interventional procedures from both the private and academic sectors of medicine. Generally Standards of Practice Committee members dedicate the vast majority of their professional time to performing interventional procedures; as such they represent a valid broad expert constituency of the subject matter under consideration for standards production. Technical documents specifying the exact consensus and literature review methodologies as well as the institutional affiliations and professional credentials of the authors of this document are available upon request from SIR, 3975 Fair Ridge Dr., Suite 400 N., Fairfax, VA 22033.

The authors describe an embolization technique that allows safe, controllable exclusion of complex vascular pathologies using a single vascular access and 2 microcatheters. This technique is particularly useful in situations where high flow increases the risk of coil migration and nontarget embolization and in large aneurysms. It affords precise placement and repositioning of coils. This method was used to treat patients with pulmonary arteriovenous malformations, renal arteriovenous fistulae and aneurysms, visceral arterial aneurysms and pseudoaneurysms, an aortic pseudoaneurysm, and occlusion of native parent vessels. The technique facilitated safe and successful endovascular closure in all cases.

The operation of E- or H-plane circulators rest on the use of either a single or a pair of re-entrant turnstile resonators. The purpose of this work is to give the mode chart of an E-plane arrangement using a single-prism resonator in WR75. The susceptance slope parameter of the device is separately summarized. The paper therefore provides a complete statement of the first circulation condition of this type of circulator.

Primary ovarian carcinoid tumours of the ovary are rare and represent less than 0.1% of ovarian malignancy. The evidence to guide treatment and prognosis of these tumours is limited. We report a case of primary ovarian mucinous carcinoid tumour, of the atypical category, in a 34-year-old nulliparous woman. Only three such cases have previously been reported. At four years from presentation, she has no signs of metastatic disease, despite delayed primary surgery and then initial conservative management. At present surgical excision with close follow-up appears to be the management of choice. This case adds to the body of evidence and demonstrates a possible good prognosis with non-aggressive behaviour in the atypical mucinous carcinoid group.

BACKGROUND: Radiographic diagnosis of acute cholecystitis can be established using ultrasonography (US), cholecystoscintigraphy (HIDA), or both. Although both modalities have been effective in diagnosing acute cholecystitis (AC), physicians from the emergency department and admitting surgeons continue to request both tests in an attempt to increase the diagnostic accuracy of AC. This article reports the institutional experience of a large tertiary care health care facility, with respect to the sensitivity of US, HIDA, and combined US and HIDA. STUDY DESIGN: We conducted a retrospective review of 132 patients diagnosed with AC who underwent laparoscopic cholecystectomy during the same hospitalization. Patients were stratified into three groups: Group 1 (Gp1, n=50) included patients who underwent US alone, group 2 (Gp2, n=28) included patients who underwent HIDA scan alone, and group 3 (Gp3, n=54) included patients who underwent both US and HIDA. RESULTS: The three groups did not differ with respect to age, liver chemistry, time to operation, and hospital length of stay. The sensitivity of US, HIDA, and combined US/HIDA as diagnostic modalities for acute cholecystitis was referenced to histopathologic confirmation. Sensitivity was 24 of 50 (48%), 24 of 28 (86%), and 49 of 54 (90%) for US, HIDA, and the combination of US/HIDA, respectively. CONCLUSIONS: HIDA scan is a more sensitive test than US in diagnosing patients with AC. Based on the results of this study, we recommend that HIDA scan should be used as the first diagnostic modality in patients with suspected acute cholecystitis; US should be used to confirm the presence of gallbladder stones rather than to diagnose AC.

Important quantities in the description of any waveguide are the definition of its propagation constant and the voltage-current, power-voltage and power-current definitions of its characteristic impedance. One purpose of this chapter is to summarise some closed form descriptions of propagation, power flow and impedance in the ridge waveguide based on the transverse resonance method (TRM). Since the different notations introduced in its characterisation are on occasion difficult to follow readily, another purpose of this chapter is to reproduce the existing literature in a single nomenclature. Still another is to summarise graphically its voltage-current, power voltage and power-current definitions of impedance in a unified way.

Anti-serum raised against the human cholecystokinin B (CCKB)/gastrin receptor was used in Western blotting to differentiate the cellular locations of receptor isoforms expressed by human gastro-intestinal (GI) tumour cell lines. Using anti-serum directed against the amino-terminal extracellular tail of the CCKB/gastrin receptor, 8/9 cell lines were shown to express immunoreactive proteins of either m.w. 70 or 40 kDa, or both. Both isoforms were found to be associated with intracellular, non-nuclear membranes, whereas only the 70 kDa protein was expressed in the plasma membrane. Receptor expression was related to gastrin production and secretion. Both progastrin and glycine-extended gastrin-17 were produced and secreted by the tumour cell lines; however, carboxy amidated gastrin was not detected by radioimmunoassay. A CCKB/gastrin receptor transfectant NIH3T3 cell line did not produce detectable gastrin and showed exclusive expression of the 70 kDa receptor on the plasma membrane. One cell line had50 pg/ml cell-associated progastrin and no detectable receptor form. Cell lines expressing 50-150 pg/ml had both 40 and 70 kDa receptor forms. Those expressing150 pg/ml progastrin had only the 40 kDa isoform, which was shown to be exclusively expressed on intracellular, non-nuclear membranes, in one of the cell lines. Of the 4 cell lines exclusively expressing the lower m.w. receptor, 3 had gastrin present within the cell, which was not secreted. Thus, if cell-associated gastrin induces a proliferative effect, it may be by an intracrine pathway. Our study has identified the presence of CCKB/gastrin receptor isoforms in different cellular locations and may help toward understanding the complex autocrine and intracrine pathways mediated by gastrin peptides.