The precise localization of advanced colorectal lesions preoperatively directs the appropriate surgical management.
The use of internal landmarks at colonoscopy can be inaccurate, therefore other methods are necessary to localize the lesions precisely.
Magnetic endoscope imaging (MEI), a real-time, nonradiographic technique for imaging of the colonoscope, may assist in determining the location of lesions found at colonoscopy.
Researchers performed a prospective study to determine the accuracy of MEI for localizing the colonoscope tip anatomically; their findings are reported in the November issue of Endoscopy.
The team used the MEI system to identify 1 of 4 predetermined locations within the colon.
|The overall accuracy of magnetic endoscope imaging was 90%.|
Once identified, 2 endoscopic marking clips were attached to the colonic mucosa, and 400 to 500 ml of radiographic contrast medium was injected to produce an air-contrast "enema".
These clips were subsequently localized using plain abdominal radiography, assessed by a single experienced radiologist who was blinded to the colonoscopic findings.
A total of 29 consecutive patients were enrolled in the study.
The research team found that the overall accuracy of MEI, when compared to the air-contrast "enema" was 90%.
They identified 3 slight errors of localization: clips localized to the descending rather than the sigmoid-descending colon junction (1), or to either side of the mid-transverse (1) and hepatic flexure (1).
However, these were not considered to be of surgical or clinical importance.
Dr Shah's team concluded, "MEI is a reliable and accurate method for determining the anatomical position of the endoscope tip during colonoscopy".
"When it becomes commercially available, we believe the use of MEI will avoid the need for unnecessary barium enemas for localization of lesions prior to definitive surgery".