Having patients lie on their left side while examining the right side of their colon during a colonoscopy can result in more polyps being found, thus increasing the effectiveness of the screening technique, according to a study in GIE: Gastrointestinal Endoscopy (2015; doi:10.1016/j.gie.2015.01.035), the scientific journal of the American Society for Gastrointestinal Endoscopy (ASGE).
Colorectal cancer (CRC) is one of the most common cancers in the United States and other western countries. Studies have shown that deaths from CRC are reduced significantly by the detection and removal of polyps through colonoscopy.
Numerous factors have been identified as important in the detection of polyps and adenomas (two types of lesions that have the potential to become cancerous if ignored), such as the length of time the colon is examined and how thoroughly the colon is prepared for the procedure. Patient position also has been identified as a factor; however, studies have been conflicting as to the effectiveness of this strategy.
This study, conducted at the Northern General Hospital of the Sheffield Teaching Hospitals in Sheffield, United Kingdom, looked at 130 patients ages 40 to 80 years who presented for a diagnostic colonoscopy at one hospital between March 2012 and February 2014.
For patients in the study, each segment of the colon was examined twice during colonoscope withdrawal. Endoscopists examined the patients in either the supine position followed by position change (to one side or another) or vice versa. The position change was to the patient’s left side for looking at the right side of the colon, or to the patient’s right side for looking at the left side of the colon.
The researchers concluded that examining the right side of the colon while the patient was on his or her left side increased polyp and adenoma detection compared with examination in the supine position.
This position change helped to bring certain segments of the colon into a place within the abdomen that allowed for optimal viewing. It also was associated with improved distension of the colon, allowing for better visualization. Polyp detection in the left side of the colon was similar whether the patient remained supine or changed position to lie on the right side.
Most of the additional polyps and adenomas detected after the position change were small and therefore not of immediate clinical significance; however, the authors pointed out that finding more lesions can change the recommendation for how soon the patient should return for his or her next colonoscopy, making the tool more effective for ongoing surveillance and prevention.