Bowel obstruction: comparison between multidetector-row CT axial and coronal planes

Bowel Obstruction

Small bowel obstruction and large bowel obstruction account for approximately 20% of cases of acute abdominal surgical conditions. The role of the radiologist is to answer several key questions: Is obstruction present? What is the level of the obstruction? What is the cause of the obstruction? What is the severity of the obstruction? Is the obstruction simple or closed loop? Is strangulation, ischemia, or perforation present? In this presentation, the radiologic approach to and imaging findings of patients with known or suspected bowel obstruction are presented.

Management of intestinal obstruction in advanced malignancy

Patients with incurable, advanced abdominal or pelvic malignancy often present to acute surgical departments with symptoms and signs of intestinal obstruction. It is rare for bowel strangulation to occur in these presentations, and spontaneous resolution often occurs, so the luxury of time should be afforded while decisions are made regarding surgery. Cross-sectional imaging is valuable in determining the underlying mechanism and pathology. The majority of these patients will not be suitable for an operation, and will be best managed in conjunction with a palliative medicine team. Surgeons require a good working knowledge of the mechanisms of action of anti-emetics, anti-secretories and analgesics to tailor early management to individual patients, while decisions regarding potential surgery are made. Deciding if and when to perform operative intervention in this group is complex, and fraught with both technical and emotional challenges. Surgery in this group is highly morbid, with no current evidence available concerning quality of life following surgery. The limited evidence concerning operative strategy suggests that resection and primary anastomosis results in improved survival, over bypass or stoma formation. Realistic prognostication and involvement of the patient, care-givers and the multidisciplinary team in treatment decisions is mandatory if optimum outcomes are to be achieved.

Visual search in abdominopelvic CT interpretation: accuracy and time efficiency between coronal MPR and axial images

RATIONALE AND OBJECTIVES

The objective of this study was to compare reader accuracy and time efficiency between coronal reformats of abdominopelvic computed tomography (CT) and axial images, by means of a visual search task.

MATERIALS AND METHODS

In this experimental crossover study, a novel visual search task, containing targets placed on actual CT images, was constructed to assess reader performance on both planes. Six trials were shown to participants in each plane, at a fixed time of 0.5 seconds per slice. The task was presented to 43 junior doctors. On each trial, participants were assessed for accuracy and confidence in finding the target on a five-point scale. Statistical analysis was performed using the Wilcoxon signed rank test, and Fleiss kappa.

RESULTS

Coronal images took 40% less time to view overall. No significant difference was found in reader accuracy or reader confidence between the two planes. Interrater agreement was observed as fair, across a very large number of raters (43).

CONCLUSIONS

Target identification in the coronal plane is extremely similar to the axial plane on abdominopelvic CT in this study and offers a substantial time benefit. A perceptual limit to visual processing of CT images may contribute to this similarity. Greater use of coronal reformats in day-to-day practice could substantially improve radiologist workflow.

The American Society for Gastrointestinal Endoscopy (ASGE) diagnostic algorithm for obscure gastrointestinal bleeding: eight burning questions from everyday clinical practice

The diagnosis and management of patients with obscure gastrointestinal bleeding are often long and challenging processes. Over the last 10 years the introduction in clinical practice of new diagnostic and therapeutic procedures (i.e. Capsule Endoscopy, Computed Tomographic Enterography, Magnetic Resonance Enterography, and Device Assisted Enteroscopy) has revolutionized the diagnostic/therapeutic work-up of these patients. Based on evidence published in the last 10 years, international scientific societies have proposed new practice guidelines for the management of obscure gastrointestinal bleeding, which include these techniques. However, although these algorithms (the most recent ones are endorsed by the American Society for Gastrointestinal Endoscopy - ASGE) allow the management of the large majority of patients, some issues still remain unsolved. The present paper reports the results of the discussion, based on the literature published up to September 2011, among a panel of experts and gastroenterologists, working with Capsule Endoscopy and with Device Assisted Enteroscopy, attending the 6th annual meeting of the Italian Club for Capsule Endoscopy and Enteroscopy. Eight unresolved issues were selected: each of them is presented as a "Burning question" and the "Answer" is the strategy proposed to manage it, according to both the available evidence and the discussion among participants.

Malignant bowel obstruction: a review of current treatment strategies

Malignant bowel obstruction is common in individuals with intra-abdominal and pelvic malignancies and results in considerable suffering. Treatments target both the resolution of obstruction and symptom management. Emerging procedures include stents placement in the bowel to return patency and newer surgical procedures that are evolving to be less invasive. The use of medical interventions like corticosteroids, alone or in concert with additional drugs, can be utilized to achieve resolution of obstruction. Throughout treatment, it is important to also aggressively treat obstructive symptoms like pain and nausea/vomiting. This can mostly be achieved with medications, but use of venting percutaneous endoscopic gastrostomy (PEG) can also relieve symptoms. Parenteral hydration and nutrition use remain controversial with this population. The factor most closely tied to prognosis is performance status.

Improving the management of acute adhesive small bowel obstruction with CT-scan and water-soluble contrast medium: a prospective study

PURPOSE

Adhesive small bowel obstruction is usually managed nonoperatively, but there is still debate over the optimal duration of nonoperative management and the factors that predict failure of medical treatment. The aim of this study was to evaluate an algorithm using CT-scans and Gastrografin in the management of small bowel obstruction.

METHODS

In a prospective study, each patient admitted for small bowel obstruction underwent a physical examination, a plain film, and a CT-scan evaluation. Patients underwent emergency surgical exploration when bowel ischemia was suspected. Other patients received oral Gastrografin, and a second plain abdominal radiograph was done after 12 hours. In patients with clinical improvement, the nasogastric tube was removed and an immediate liquid diet was resumed. Other patients were referred for surgery.

RESULTS

In total, 118 patients with 123 episodes of small bowel obstruction were included. Thirty-six (29%) required immediate surgery because they presented clinical characteristics of bowel ischemia (36/36; 100%) or a defect in vascularization of the small bowel on CT-scan (5/36; 14%). The 87 remaining patients were managed nonoperatively, of which 28 deteriorated and were referred for surgery. The 59 other patients showed clinical improvement.

CONCLUSION

This study demonstrated the diagnostic role of Gastrografin(R) in discriminating between partial and complete small bowel obstruction. CT-scans were disappointing in their ability to predict the necessity of emergent laparotomies. We therefore recommend the use of Gastrografin(R) in adhesive small bowel obstruction patients who do not have clinical evidence of bowel ischemia. CT-scans should not be routinely performed in the decision-making process except when clinical history, physical examination, and plain film are not conclusive for small bowel obstruction diagnosis.

[Multidetector computed tomography in abdominal emergencies]

Abdominal emergencies encompass traumatic events in the region of the abdomen as well as the clinical term acute abdomen. Multidetector CT (MDCT) represents one of the most important imaging modalities for detection and correct diagnosis in such abdominal emergencies. Based on the acquired data MDCT allows a stable imaging of the abdomen in an extremely short time even in critically ill patients. Multiplanar reconstructions can be created based on the high resolution data allowing an impressive visualization of the pathology. In this review article the most important abdominal pathologies of the abdomen diagnosed by MDCT are presented with special emphasis on the liver, bile ducts, spleen and kidneys as well as the gastro-intestinal tract. Additionally, MDCT imaging of the individual organ regions will be dealt with in detail.

3D CT imaging in clinical practice

Recent technological advances in multidetector computed tomography (MDCT) have enabled 3D diagnostic imaging with superb spatial and temporal resolution. This often provides useful information on precise detail and relationships.