Advanced endografting techniques: snorkels, chimneys, periscopes, fenestrations, and branched endografts.

The anatomy of aortic aneurysms from the proximal neck to the access vessels may create technical challenges for endovascular repair. Upwards of 30% of patients with abdominal aortic aneurysms (AAA) have unsuitable proximal neck morphology for endovascular repair. Anatomies considered unsuitable for conventional infrarenal stent grafting include short or absent necks, angulated necks, conical necks, or large necks exceeding size availability for current stent grafts. A number of advanced endovascular techniques and devices have been developed to circumvent these challenges, each with unique advantages and disadvantages. These include snorkeling procedures such as chimneys, periscopes, and sandwich techniques; "homemade" or "back-table" fenestrated endografts as well as manufactured, customized fenestrated endografts; and more recently, physician modified branched devices. Furthermore, new devices in the pipeline under investigation, such as "off-the-shelf" fenestrated stent grafts, branched stent grafts, lower profile devices, and novel sealing designs, have the potential of solving many of the aforementioned problems. The treatment of aortic aneurysms continues to evolve, further expanding the population of patients that can be treated with an endovascular approach. As the technology grows so do the number of challenging aortic anatomies that endovascular specialists take on, further pushing the envelope in the arena of aortic repair.

ACR Appropriateness Criteria radiologic management of benign and malignant biliary obstruction.

The optimal treatment for patients with biliary obstruction varies depending on the underlying cause of the obstruction, the clinical condition of the patient, and anticipated long-term effects of the procedure performed. Endoscopic and image-guided procedures are usually the initial procedures performed for biliary obstructions. Various options are available for both the radiologist and endoscopist, and each should be considered for any individual patient with biliary obstruction. This article provides an overview of the current status of radiologic procedures performed in the setting of biliary obstruction and describes multiple clinical scenarios that may be treated by radiologic or other methods. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

ACR Appropriateness Criteria radiologic management of hepatic malignancy.

Management of hepatic malignancy is a challenging clinical problem involving several different medical and surgical disciplines. Because of the wide variety of potential therapies, treatment protocols for various malignancies continue to evolve. Consequently, development of appropriate therapeutic algorithms necessitates consideration of medical options, such as systemic chemotherapy; surgical options, such as resection or transplantation; and locoregional therapies, such as thermal ablation and transarterial embolization. The authors discuss treatment strategies for the 3 most common subtypes of hepatic malignancy treated with locoregional therapies: hepatocellular carcinoma, neuroendocrine metastases, and colorectal metastases. The ACR Appropriateness Criteria(®) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

ACR appropriateness criteria® radiologic management of thoracic nodules and masses.

Pulmonary and mediastinal masses represent a wide range of pathologic processes with very different treatment options. Although advances in imaging (such as PET and high-resolution CT) help in many cases with the differential diagnosis of thoracic pathology, tissue samples are frequently needed to determine the best management for patients presenting with thoracic masses. There are many options for obtaining tissue samples, each of which has its own set of benefits and drawbacks. The purposes of this report are to present the most current evidence regarding biopsies of thoracic nodules and masses and to present the most appropriate options for select common clinical scenarios. The ACR Appropriateness Criteria(®) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

ACR Appropriateness Criteria® on treatment of uterine leiomyomas.

Uterine leiomyomas (fibroids) are the most common tumors in women of reproductive age and a cause of significant morbidity in this patient population. Depending on the fibroid location, they can be the cause of a variety of symptoms, such as abnormal uterine bleeding, constipation, urinary frequency, and pain. Historically, hysterectomy has been the primary treatment option, and uterine fibroids remain the leading cause for hysterectomy in the United States. However, women who do not wish to undergo hysterectomy now have a variety of less invasive options available, including uterine artery embolization. This article discusses uterine artery embolization as well as some of the other treatment strategies for symptomatic uterine fibroids. In many situations, there may be no single best treatment option but several viable alternatives. Each option is discussed with consideration of outcomes, complications, and, when possible, cost-effectiveness. The recommendations in this article are the result of evidence-based consensus of the ACR Appropriateness Criteria® Expert Panel on Interventional Radiology.

ACR Appropriateness Criteria on percutaneous catheter drainage of infected fluid collections.

Abnormal fluid collections occur throughout the body and represent a wide range of pathologies, including abscesses, pseudocysts, cysts, lymphoceles, seromas, bilomas, hematomas, urinomas, and infected neoplasms. Appropriate management often depends on clinical presentation, location, type of collection, early response to treatment, and the presence of complicating factors such as fistulas, septations, and increased viscosity. Physicians should carefully review clinical and imaging findings and make evidence-based recommendations for the best treatment, which may include antibiotics, needle aspiration, percutaneous drainage, endoscopic drainage, or surgical drainage. This paper addresses percutaneous catheter drainage and alternative treatment options for the management of fluid collections and is the result of evidence-based consensus by the ACR Appropriateness Criteria Expert Panel on Interventional Radiology.

Management of early group A streptococcus fasciitis by imaging-guided percutaneous drainage.

Group A streptococcus (GAS) is associated with a spectrum of soft-tissue infections that include toxic shock syndrome, myositis, and necrotizing fasciitis (1, 2, 3). The mainstay of therapy for invasive GAS soft-tissue infections is surgical exploration and debridement, as penicillin treatment alone is associated with a high morbidity and mortality (4). We report a case that suggests that imaging-guided percutaneous drainage may have a role in the treatment of some cases of GAS fasciitis, and may preclude the need for surgical intervention.