Biomedical subjects
Publications and source records attributed to John C Lappas.
OBJECTIVE: Our objective was to report the CT features of biliopancreatic limb (afferent loop) obstruction. CONCLUSION: Acute biliopancreatic limb obstruction has typical CT features. Given its high morbidity and rate of reoperation, it is useful to make this specific diagnosis instead of reporting the findings as postoperative small bowel obstruction.
OBJECTIVE: Surgery is increasingly undertaken for intractable chronic pancreatitis. We evaluated the postsurgical anatomy and complications of surgical options including Whipple, Puestow, Frey's, and Beger's procedures. CONCLUSIONS: Knowledge of postsurgical anatomy is important to avoid misdiagnosing expected anatomy as complications on CT examinations. It is important to carefully assess the upper abdominal arteries to detect subtle but potentially lethal complications.
OBJECTIVE: Gastrointestinal complications of major abdominal surgery often require radiologic assessment. The purpose of this article is to review the expected imaging findings and complications after commonly performed gastric and pancreatic surgery. CONCLUSION: It is important to understand the postsurgical anatomy to avoid misinterpreting an expected postoperative finding as a complication. Postoperative complications can be categorized as being related to adhesions, anastomosis, an enteric connection, and abnormal bowel position.
Obesity is rapidly becoming the most important public health issue in USA and Europe. Roux-en-Y gastric bypass is now established as the gold standard for treating intractable morbid or super obesity. We reviewed the imaging findings following this surgery in 234 patients. In this pictorial essay we present the CT and upper gastrointestinal contrast study appearances of the expected postoperative anatomy as well as a range of abdominal complications. The complications are classified into leaks, fistula and obstruction. Postoperative gastric outlet and small bowel obstruction can be caused by anastomotic stenosis, mesocolic tunnel stenosis, adhesions, stomal ulcer, obturation, intussusception and internal or external hernia. Small bowel obstruction may be of a simple, closed loop and/or strangulating type. The radiologist should be able to diagnose the type and possible cause of obstruction.
The diagnosis and treatment of small bowel obstruction continue to evolve. The imaging approach in the work-up of patients with known or suspected small bowel obstruction and the timing of surgical intervention in this disease have undergone considerable changes over the past two decades. This article examines the current concepts related to the use of imaging technology in the diagnosis and management of patients with small bowel obstruction. The meaning of frequently used but poorly defined terms in describing intestinal obstruction is clarified and illustrated.
Currently, CT-E is not recommended as the first-line examination in patients when mucosal detail is required. Double-contrast barium air enteroclysis has advantages in demonstrating small mucosal abnormalities. The authors find CT-E of value in the work-up of patients with symptoms of intermittent small bowel obstruction, particularly those with a history of prior abdominal surgery; in the further work-up of selected patients with high-grade obstruction in whom general surgeons prefer initial conservative management (immediate postoperative small bowel obstruction, patients with history of prior abdominal surgery for malignant tumor, history of radiation treatment, and possible internal extraintestinal fistulae); in looking for complications of small bowel Crohn's disease; and in the patient with unexplained anemia or gastrointestinal bleeding. In a series of patients who had both abdominal CT and barium enteroclysis done, each examination provided unique and complimentary diagnostic information. Because CT-E combines the advantages of both methods of examination, is it the optimum imaging work-up in the investigation of small bowel disease? Further research and clinical experience will define the precise role of CT-E in the investigation of small bowel disease. Experience with this method of examination is limited to a few institutions, performed by investigators with interest in small bowel diseases. The addition of cross-sectional display and multiplanar reformatting made possible by multidetector-row helical CT to enteral volume change and the use of multifunctional nasointestinal catheters make CT-E an important tool in the investigation of small bowel disease. Experience has shown the increased reliability of any method of examining the small bowel that challenges intestinal wall distensibility by fluid enteral volume infusion.
The small bowel is subject to a variety of surgical interventions for the treatment of a broad spectrum of disease processes. Most operative procedures applied to the small bowel are straightforward techniques encumbered by few complications, whereas other procedures are considerably more complex and can be associated with significant postoperative morbidity. Familiarity with the anatomic alterations related to the various operations is essential, both for evaluation of early postoperative complications and those abnormalities that manifest late in the postoperative course. The surgeon and radiologist should carefully coordinate clinical suspicion with the strengths of the various imaging modalities to optimize postsurgical assessment and provide timely and accurate diagnosis. Enteric anastomoses, the different forms of enterostomy, and the varied constructions of small bowel pouches and reservoirs are each associated with unique anatomy and therefore optimal techniques of assessment. Small bowel contrast studies such as enteroclysis--including its recent modification, CT enteroclysis--and CT imaging represent the primary modalities for imaging of the postoperative bowel and its related abnormalities. Small bowel transplantation continues to progress as a realistic treatment for intestinal failure, and the role of diagnostic imaging in these unique and challenging patients is evolving.
As the primary method of investigating the small bowel, enteroclysis remains a technique in evolution. Technical refinements have made the examination faster to perform, better tolerated by patients, and easier to interpret. More recently, its essential principle of volume challenge has been combined with the tremendous advantage of CT cross-sectional imaging with multiplanar reformatting to give rise to the exciting new techniques of CT enteroclysis and MR enteroclysis (see separate reviews in this issue). Through improvements in methodology and advancements in technology, the future of enteroclysis looks bright indeed.
Small bowel obstruction is a common clinical condition, often presenting with signs and symptoms similar to those seen in other acute abdominal disorders. The diagnosis and treatment of this dynamic process continues to evolve. The imaging approach in the work-up of patients with known or suspected small bowel obstruction and the timing of surgical intervention in this disease have undergone considerable changes over the past two decades. This article examines the changes related to the use of imaging technology in the diagnosis and management of patients with small bowel obstruction. The meaning of frequently used but poorly defined terms in describing intestinal obstruction is clarified and illustrated.