An International Symposium was held in Atlanta in 1992 to present the state of the art of diagnostic evaluation and management of acute pancreatitis and to agree on an acceptable series of clinical definitions for classifying the disease and its complications. The symposium was composed of 40 internationally recognized experts in pancreatic disease from 15 countries representing six disciplines (anatomy, gastroenterology, internal medicine, pathology, radiology, and surgery). The purpose of this article is to present the radiologically relevant aspects of the symposium; to define the state of the art of imaging and intervention in acute pancreatitis, particularly how and when to use computed tomography and how and when to perform percutaneous therapy versus surgery; and to encourage radiologists to use precise and proper nomenclature when describing the morphologic manifestations of acute pancreatitis as depicted by various imaging modalities.

Computed tomography (CT) was used to guide percutaneous fine-needle biopsy in 150 cases of difficult thoracic lesions; in 76 cases, nondiagnostic bronchoscopy (n = 62) and fluoroscopic biopsy (n = 14) had previously been performed. CT was indicated for guidance when the pulmonary or pleural lesions were small (0.3-2.5 cm); in a juxta-vascular location, either hilar or mediastinal; not seen or poorly visualized on conventional radiographs; or considered inaccessible. A diagnosis was made in 124 of 150 cases (82.7%) (107 of 124 malignant and 17 of 26 benign lesions), including 86 of 107 lung nodules (80.4%), 28 of 31 mediastinal lesions (90.3%), and ten of 12 pleural masses (83.3%). Complications included pneumothorax (n = 64), hemoptysis (n = 5), hemothorax (n = 2), and pericarditis (n = 1). The high rate of pneumothorax, its treatment, and advantages of its immediate radiologic management are discussed. Use of CT guidance considerably expands the scope of thoracic lesions amenable to percutaneous biopsy.

Pancreatic and peripancreatic necrosis may result in significant morbidity and mortality in patients with acute pancreatitis. Many recommendations have been made for management of necrotizing pancreatitis, but no published guidelines have incorporated the many recent developments in minimally invasive techniques for necrosectomy. Hence, a multidisciplinary conference was convened to develop a consensus on interventions for necrotizing pancreatitis. Participants included most international experts from multiple disciplines. The evidence for efficacy of interventions was reviewed, presentations were given by experts, and a consensus was reached on each topic. In summary, intervention is primarily indicated for infected necrosis, less often for symptomatic sterile necrosis, and should ideally be delayed as long as possible, preferably 4 weeks or longer after the onset of disease, for better demarcation and liquefaction of the necrosis. Both the step-up approach using percutaneous drainage followed by minimally invasive video-assisted retroperitoneal debridement and per-oral endoscopic necrosectomy have been shown to have superior outcomes to traditional open necrosectomy with respect to short-term and long-term morbidity and are emerging as treatments of choice. Applicability of these techniques depends on the availability of specialized expertise and a multidisciplinary team dedicated to the management of severe acute pancreatitis and its complications.

During the approximately 20 years that percutaneous abscess drainage (PAD) has been an extant procedure and as the millennium begins, PAD has become, by consensus, the treatment of choice for abscesses. Indications for PAD continue to expand, and currently almost all abscesses are considered amenable. On occasion, PAD is an adjunctive procedure that provides a beneficial temporizing effect for the surgeon who eventually must operate for a coexisting problem such as a bowel leak. Simple unilocular abscesses are cured almost uniformly by PAD; more complicated abscesses, such as those with enteric fistulas (e.g., diverticular abscess) or pancreatic abscesses, have cure rates ranging from 65% to 90%. Various catheters and insertion techniques have proven effective. Ultrasonography, computed tomography, and fluoroscopy are the staple modalities that guide PAD. PAD is the prototype interventional radiology procedure, providing detection of the abscess by imaging, needling for diagnosis, and catheterization for therapy.

Percutaneous drainage of 101 pancreatic pseudocysts (51 infected, 50 noninfected) in 77 patients is described. In this group of patients, 91 of 101 pseudocysts were cured by means of catheter drainage (90.1%) (noninfected, 43 of 50 [86%]; infected, 48 of 51 [94.1%]). Six patients underwent operation after percutaneous treatment due to persistent drainage. In patients with infected pseudocysts, the infection was eradicated by percutaneous drainage before operation. Four pseudocysts recurred and were redrained percutaneously. The mean duration of drainage was 19.6 days (infected pseudocysts, 16.7 days; noninfected, 21.2 days). Various access routes were used for catheter drainage: transperitoneal, retroperitoneal, transhepatic, transgastric, transduodenal, and transsplenic (inadvertent). Four major (superinfections) and six minor complications occurred. An unexpected finding in seven patients was spontaneous fistulization of the pseudocyst into the gastrointestinal tract. Percutaneous drainage is an effective front-line treatment for most pancreatic pseudocysts; cure is likely if fluid collections are drained adequately and if sufficient time is allowed for closure of fistulas from the pancreatic duct.

The modified CT severity index correlates more closely with patient outcome measures than the currently accepted CT severity index, with similar interobserver variability.

Percutaneous sclerotherapy with doxycycline is safe and appears effective for palliative treatment of unresectable lymphangiomas on the basis of our initial clinical experience.

MR imaging-guided percutaneous cryotherapy of liver tumors is feasible and safe. MR imaging can be used to estimate cryotherapy effects and guide therapy intraprocedurally.