E1060. Ultrasound of the Acute Bowel with CT Correlation: Critical Diagnostic Pearls
University of Toronto
University of Toronto
The use of ultrasound (U/S) as a primary imaging tool for the assessment of the acute bowel has many advantages, such as being non-invasive, lack of exposure to ionizing radiation, inexpensive, widely available, ability to assess bowel motility in real time, and allowing direct correlation between U/S findings and area of maximum tenderness or a palpable mass. However, U/S remains under-utilized in most medical care centres due to operator dependency and technical challenges including, but not limited to, body habitus, patient cooperation, prolonged studies, and lack of familiarity with appropriate technique. The purpose of this exhibit is to describe proper U/S technique and diagnostic criteria of acute bowel cases, outside of inflammatory bowel disease. Computed Tomography (CT) correlates of findings are included to demonstrate the remarkable accuracy of this modality when used in an effective manner.
Educational Goals / Teaching Points
1. To provide an overview of proper U/S technique
2. To describe common acute bowel cases
3. To describe proper U/S technique and diagnostic criteria pertaining to specific common acute bowel cases
4. To provide CT correlation for each case
Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
The exhibit begins with a review of the correct technique and choice of transducers for the assessment of bowel and associated structures. This is followed by a presentation of normal and abnormal appearance of bowel on U/S imaging. A case-based review of the following pathology is included in this exhibit:
- Acute appendicitis (uncomplicated and perforated)
- Appendiceal mucocele
- Diverticulitis (left sided and right sided, with and without complications)
- Acute colitis (focal and diffuse)
- Acute epiploic appendagitis (right sided and left sided)
Each case is presented with a brief clinical history followed by multiple sonographic images demonstrating the pertinent findings. CT correlates are provided for each case to emphasize that using correct technique, findings on CT are well reproducible sonographically. The clinical outcomes of cases are also included. A brief discussion of important pearls in the sonographic assessment and diagnosis for each pathological presentation is then provided.
U/S is an effective tool to diagnose acute bowel pathologies. Familiarizing radiologists and U/S technologists with this skill has many advantages, including avoiding radiation exposure (particularly important for young patients), increased efficiency, and minimizing costs to the health care worker. In uncomplicated acute bowel processes, the need for further imaging by CT (with increased risk of radiation exposure) can be eliminated by accurate sonographic assessment and diagnosis. In equivocal cases, the study can be repeated in short intervals without risks of recurrent exposures. However, it is important to note that in cases where complications are suspected (bowel perforation, obstruction, abscess, etc.), initial or further imaging by CT is still required for assessment of the extent and further characterization of the abnormality.